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Articles in press have been peer-reviewed and accepted, which are not yet assigned to volumes /issues, but are citable by Digital Object Identifier (DOI).
Isolation and identification of pathogenic fungi of stem rot in Crocus sativus
WU Jiening, GUI Siqi, CAO Jiajia, DU Xue, LI Junbo, LI Xiujuan, KAI Guoyin, ZHOU Wei
doi: 10.11833/j.issn.2095-0756.20210768
[Abstract](0) [HTML](0) [PDF](0)
  Objective  This study, with an investigation into the identification and isolation of the rot disease pathogen of Crocus sativus, the main disease of which is fungal disease, is intended to provide scientific basis for the prevention and control of saffron stem rot and the development of special fungicides.   Method  First, the pathogenic fungi were isolated from infected corms by tissue separation method using ‘Saffron No. 1’ as the test material. Then an analysis was made of the sequences of conserved internal transcribed spacer (ITS) and RNA polymerase Ⅱ subfamily (RPB2) by PCR amplification, sequencing and phylogenetic tree construction. At last, pathogenic bacteria were isolated from infected corms and grafted back to plants to verify the pathogenic characteristics of fungi under the planting mode of saffron.   Result  The morphological characteristics of the corm-pathogenic fungi isolated were highly similar to those of Aspergillus niger. The conserved sequences of ITS and RPB2 of the candidate pathogenic fungi had 99.6% homology to the same DNA sequence of A. niger from other plants with the same evolutionary branch. In the soil planting mode, inoculation with A. niger solution significantly increased the incidence of corm (P<0.01).   Conclusion  A. niger is one of the fungal diseases that cause the rot of saffron bulbs. [Ch, 7 fig. 32 ref.]
Research progress on soil microorganisms in eucalypt forests
WEI Juxian, WANG Cong, HE Bin, YOU Yeming, HUANG Xueman
doi: 10.11833/j.issn.2095-0756.20210701
[Abstract](5) [HTML](3) [PDF](0)
As one of the three major fast-growing tree species in the world, eucalypt is featured with great variety, strong resistance to stress and wide adaptability. It is significant to research the diversity and functions of soil microorganisms which affect the growth of trees by participating in the processes of nutrient element cycling and energy flow and play an important role in improving soil fertility and productivity. However, with limitations in knowledge of soil microbial communities and functions due to the complexity of the eucalypt forest ecosystem and research techniques of soil microbiology, researches on the characteristics of soil microbial communities in eucalypt forests so far are still in the primary stage. This study is aimed to conduct a systematic review of the research progress on soil microbial characters in eucalypt forests with different management patterns, stand types and stand ages. Compared with natural forests of eucalypt, there was generally a lower soil microbial abundance in eucalypt plantations whereas there was an increase in the abundance, diversity, and activity of soil microorganisms in eucalypt mixed forests compared with eucalypt plantation pure forests and the abundance of soil microorganisms in eucalypt forests generally increased with the age of the forest, while the diversity of ectomycorrhizal and endomycorrhizal fungi decreased with the age of the forest. In addition, with an analysis of the mechanism of soil microorganisms involved in nutrient element cycling and remediation of heavy metal pollution in eucalypt forests and prospects of future research and analyzing methods of soil microbiome and application of microorganisms, this study will provide scientific guidance for the maintenance of forest soil health and the promotion of green and sustainable forestry development. [Ch, 1 tab. 94 ref.]
Cloning and functional analysis of SvAPETALA1 in Senecio vulgaris
HAO Yanmin, CHEN Keli, FENG Lijun, LI Feifei, CUI Minlong, PIAO Chunlan
doi: 10.11833/j.issn.2095-0756.20210651
[Abstract](8) [HTML](3) [PDF](0)
  Objective  Floral organ development is an important factor affecting the ornamental value of flowers, and APETALA1(AP1) genes regulate the formation of floral organs. This study aims to explore the important role of SvAP1 gene of Senecio vulgaris (Asteraceae) in floral organ formation, so as to reveal the regulatory mechanism of the complex inflorescence structure in Asteraceae.   Method  SvAP1 gene was cloned from S. vulgaris. The function of SvAP1 gene was predicted and analyzed by multiple sequence alignment, phylogenetic tree construction, qRT-PCR, overexpression vector construction, and histological staining observation.  Result  The open reading frame (ORF) of SvAP1 gene was 705 bp in length, and encoded 234 amino acids. Multiple sequence alignment and phylogenetic analysis showed that SvAP1 gene belonged to AP1 subfamily of MADS-box gene, and the C-terminus had a conserved motif of paleoAP1. Tissue specific expression analysis of S. vulgaris showed that SvAP1 gene was expressed in both vegetative organs and inflorescences. Morphological observation and paraffin section analysis of transgenic Solanum nigrum showed that compared with wild S. nigrum, the pistil development of transgenic S. nigrum was abnormal, which was characterized by enlarged ovary and increased pistil-like tissue.  Conclusion  The overexpression of SvAP1 gene in S. nigrum affects the pistil development, which is different from the effect of over expression of class A gene in ABC model on floral organ development, that is, the stamens of transgenic S. nigrum have no obvious changes and the pistils aren’t transformed into sepal or leaf-like organs, which may be related to the complexity of the floral organ regulation mechanism and the inflorescence structure of S. vulgaris. In conclusion, SvAP1 gene may play an important role in floral organ formation as a characteristic gene of floral organ. [Ch, 6 fig. 1 tab. 35 ref.]
Temporal and spatial relationship between spiders and Ricanidae in tea gardens
XU Yue, WU Xiaomeng, CHEN Shiyan, CHENG Honghao, ZHANG Lin, ZHOU Xiazhi, ZOU Yunding, BI Shoudong
doi: 10.11833/j.issn.2095-0756.20210734
[Abstract](8) [HTML](4) [PDF](0)
  Objective  The objective of this study is to exlore the temporal and spatial relationship between natural enemies of spiders and Ricanidae, so as to provide scientific basis for the use and protection of natural enemies.  Method  Geostatistics, grey system analysis and niche analysis were used to analyze the population dynamics of Ricanidae and 11 spiders during their blooming period in 6 kinds of tea gardens, including ‘Anjibaicha’, ‘Huangshandayezhong’, ‘Longjing 43’, ‘Nongkangzao’, ‘Pingyangtezao’ and ‘Wuniuzao’. The close degree of temporal and spatial relationship between 11 species of spiders and Ricanidaein was studied.  Result  According to the sum of spatial closeness indices of the 6 tea plantations, the top 5 spiders closely related to the space of Ricanidae were Xysticus ephippiafus (5.7415), Oxyopes sertatus (5.6942), Erigonidium graminicolum (5.6986), Theridion octomaculatum (5.6502) and Clubiona japonicola (5.5373) in descending order. According to the sum of time relationship index, the top 5 spiders closely related to the time of Ricanidae were E. graminicolum (5.6026), Misumenops tricuspidatus (5.4279), Theridion octomaculatum (5.3519), Tetragnatha squamata (5.0791) and Tetragnatha maxillosa (5.0686).   Conclusion  According to the comprehensive analysis, the top 3 spiders closely related to the time and space of Ricanidae from large to small are E. graminicolum (11.2912), Theridion octomaculatum (11.0021) and M. tricuspidatus (10.9935). [Ch, 10 tab. 27 ref.]
Properties of bio-pretreated straw fiber and its composite materials
DU Keke, YONG Cheng, SUN Enhui, HUANG Hongying, QU Ping, XU Yueding, CHEN Ling, SUN Qian, GUAN Mingjie
doi: 10.11833/j.issn.2095-0756.20210647
[Abstract](4) [HTML](2) [PDF](0)
  Objective  This study aims to explore the influence of biological pretreatment on the properties of straw fiber and its composites prepared with urea formaldehyde resin, so as to provide theoretical basis for the preparation and development of straw based composites.   Method  Rice (Oryza sativa) straw was treated with microbial agent for aerobic fermentation. The changes of hemicellulose, cellulose and lignin in rice straw under different treatment time were measured. The crystallinity and microscopic morphology of straw fiber without biological pretreatment (S0), straw fiber bio-pretreated for 5 days (S5) and 10 days (S10) were tested and compared. Straw fiber/urea formaldehyde resin composites (F0, F5, F10) were prepared. Then the surface properties and mechanical properties of straw based composites under different biological pretreatment time were compared.   Result  Substances such as silicon and wax on the surface of straw fiber were removed after biological pretreatment, but the longer biological pretreatment time (10 d) could destroy the structure of straw fiber itself. Compared with S0 and S10, S5 had the highest relative content of cellulose (37.99%) and best crystallinity (47.8%). In contrast, F5 had the best hydrophobicity, lowest surface energy, and highest impact toughness (7 665.64 J·m−2). F10 had the best flexural performance. The static flexural strength and flexural modulus were 27.73 and 20 354 MPa, respectively, which were 59.00% and 50.17% higher than the composites prepared by S0, respectively.   Conclusion  Biological pretreatment can improve the surface properties of straw fiber and the properties of straw fiber/urea formaldehyde resin composites. The straw fiber bio-pretreated for 5 days is better, and the properties of the composites are superior. [Ch, 4 fig. 1 tab. 28 ref.]
Individual tree detection in high canopy density Larix principis-rupprechtii plantation based on airborne LiDAR
CHEN Siyu, LIU Xianzhao, WANG Yixiang, LIANG Dan
doi: 10.11833/j.issn.2095-0756.20210399
[Abstract](14) [HTML](2) [PDF](0)
  Objective  With low identification accuracy of individual trees in Larix principis-rupprechtii forest with high canopy density employing high resolution images, this paper is aimed to confirm the strengths of airborne Laser Detection and Ranging (LiDAR) 3D point cloud data as an alternative with a workable method proposed.   Method  Based on the preprocessing of point cloud data, an improved Mean Shift with Gaussian kernel function (MSP) position recognition method on the basis of the spatial characteristics of airborne LiDAR point cloud was proposed. The comparison is made with other three commonly used methods: regional growing segmentation algorithm based on point cloud (RGP), local maximum method based on canopy height model (LMC) and multi-scale segmentation method based on CHM (MSC).   Result  Identification accuracy of the four methods is: MSP (89.30%)>LMC (85.60%)>RGP (77.50%)>MSC (70.00%) and MSC, the proposed method, displayed high average individual tree crown extraction accuracy (90.18%) and relatively low omission error and commission error rate: 8.7% and 8.0% respectively.   Conclusion  The proposed MSP has good applicability in high crown density L. principis-rupprechtii forest and provides a new way of extracting L. principis-rupprechtii forest structure parameters accurately on the basis of airborne LiDAR point clouds. [Ch, 3 fig. 3 tab. 28 ref.]
Spatial distribution of endangered orchids in the Yangtze River Watershed
ZHANG Yilin, LI Gongquan, LIU Ying
doi: 10.11833/j.issn.2095-0756.20210551
[Abstract](8) [HTML](1) [PDF](0)
  Objective  This study, with an investigation of the scientific and standard identification of the migration of Orchidaceae, a protected and flagship group, in the Yangtze River Watershed, is aimed at an exploration of the spatial distribution of endangered orchids and the determination of key protected species and hot spots so as to serve the better research and protection of rare and endangered orchids.   Method  Taking the representative Orchidaceae plants in the Yangtze River Watershed from 1981 to 2019 as the research object, 130 species distribution points of 10 species including Neottianthe and Pleione were selected based on the field investigation and Global Biodiversity Information Facility (GBIF) database. Then, with the guidance of the theory of phytogeography and the conduct of a GIS spatial analysis, the spacial distribution of endangered orchids was investigated employing kernel density, Moran index and hot spot distribution.   Result  (1) The period between 1998 and 2019 witnessed the disappearance of Orchidaceae plants in Guangxi and Guizhou, a decrease in high-density areas of them in the Yangtze River Watershed, changes in the median density areas as well as their migration from central Sichuan to north Sichuan. (2) There was a significant positive correlation between the level of endangerment of Orchidaceae plants and their spatial location and the correlation between 1998 and 2019 was stronger than that of 1981−1997. (3) There was a shift of high risk areas: from 1981 to 1997, the high risk areas of Orchidaceae were mainly distributed in Guizhou and Hubei whereas from 1998 to 2019, they were mainly distributed in Hubei Province.   Conclusion  There have been changes in the distribution of Orchidaceae plants and a reduction in quantity which mainly attribute to global warming, infrastructure construction, illegal harvesting and excessive deforestation and in the future Hubei would become the focus of attention. [Ch, 1 fig. 5 tab. 31 ref.]
Development of a highly sensitive qualitative and quantitative immunochromatographic method for the detection of aflatoxin B1
ZHANG Xian, WANG Jixuan, CHENG Gaochuan, LI Ke, ZHANG Xiaofeng, SUN Mengjiao, CHENG Changyong, SONG Houhui
doi: 10.11833/j.issn.2095-0756.20210772
[Abstract](13) [HTML](5) [PDF](1)
  Objective  Fungal metabolites, commonly known as mycotoxins, can pollute agricultural products and food of animal origin, among which aflatoxin B1 (AFB1) is the most common, toxic and detrimental. Establishing a rapid, highly sensitive and convenient detection method of AFB1 is of great significance for the protection of human and animal health. The objective of this study is to optimize the immunochromatographic detection method based on the principle of lateral-flow chromatography and competitive mode, so as to realize the rapid qualitative detection and quantitative analysis of AFB1.   Method  A highly sensitive qualitative and quantitative immunochromatographic detection method for AFB1 was established by comparing and analyzing the labeling effects of gold particles of varying sizes, optimizing the material types of each component of immunochromatography, as well as relevant buffer solution and the optimal mass concentration.   Result  The qualitative and quantitative detection limits of the optimized AFB1 immunochromatographic method in samples were 2.5 and 0.5 μg·kg−1, respectively, with high sensitivity and specificity and no cross reaction with other common mycotoxins. Standard addition recovery experiment showed that the method was accurate and stable, and the quantitative detection results of AFB1 natural contamination samples were in good agreement with commercial kit and LC-MS/MS.   Conclusion  The immunochromatographic detection method prepared in this study can be used for rapid qualitative detection and quantitative analysis of AFB1 contamination in samples. It is suitable for grass-roots inspection and quarantine institutions and agricultural product processing enterprises that lack experimental conditions to quickly screen a large number of samples. If the sample test result is suspected to be positive, the instrument method can be used for confirmation, which can reduce the test cost, improve the test efficiency and provide reference for the establishment of immunochromatographic detection methods for other pathogenic microorganisms. [Ch, 9 fig. 2 tab. 26 ref.]
Effects of arbuscular mycorrhizal fungi symbiosis on growth and photosynthetic characteristics of Fraxinus malacophylla in rocky desertification habitats
YANG Bo, WANG Shaojun, ZHAO Shuang, ZHANG Lulu, ZHANG Kunfeng, FAN Yuxiang, XIE Lingling, WANG Zhengjun, GUO Zhipeng, XIAO Bo
doi: 10.11833/j.issn.2095-0756.20210740
[Abstract](10) [HTML](5) [PDF](0)
  Objective  This study aims to explore the effects of arbuscular mycorrhizal (AM) fungal symbiosis on growth and photosynthetic characteristics of Fraxinus malacophylla in rocky desertification habitats, so as to provide data reference for selecting dominant AM fungal species for vegetation restoration.   Method  An experiment was designed with four treatments: Funneliformis mosseae+agroforestry biofertilizer (MN), Claroideoglomus etunicatum+agroforestry biofertilizer (YN), Rhizophagus intraradices+agroforestry biofertilizer (GN) and agroforestry biofertilizer (ck). The changes in F. malacophylla growth (tree height, diameter at breast height, leaf and root biomass, leaf area, leaf pigment and chlorophyll) and photosynthetic characteristics (net photosynthetic rate, stomatal conductance, intercellular CO2 concentration, transpiration rate, and leaf water use efficiency, etc.) were measured under different treatments.   Result  (1) Inoculation with AM fungi significantly promoted the growth of F. malacophylla and biomass accumulation of leaf and root(P<0.05). (2) Inoculation with MN and GN significantly increased the relative contents of chlorophyll a, chlorophyll b and lutein in plant leaves (P<0.05), and the increase rate was 6%−67%. (3) Inoculation with AM fungi significantly increased the net photosynthetic rate, stomatal conductance, transpiration rate, and water use efficiency of F. malacophylla (P<0.05), but significantly decreased the intercellular CO2 concentration (P<0.05). (4) Principal component analysis indicated that the stomatal conductance, tree height, and lutein were the key factors to increase the net photosynthetic rate, with an average contribution rate of 45.81%, followed by chlorophyll b, biomass and total chlorophyll.   Conclusion  AM fungal symbiosis can significantly improve the net photosynthetic rate of F. malacophylla by promoting plant growth and photosynthetic pigment content. The optimal strain is F. mosseae. [Ch, 5 fig. 2 tab. 33 ref.]
Response of leaf functional traits of Fraxinus malacophylla seedlings to calcium
ZHANG Mei, DONG Qiong, DUAN Huachao, YE Lan, LI Yanyan, JIN Youfan
doi: 10.11833/j.issn.2095-0756.20210597
[Abstract](11) [HTML](2) [PDF](1)
  Objective  This study, with an investigation of the effects of different calcium concentrations on leaf morphological indexes, chlorophyll content and enzyme activity of Fraxinus malacophylla seedlings, is aimed to better understand the growth and development of F. malacophylla seedlings under different calcium concentrations so as to further explore the environmental adaptability of F. malacophylla seedlings when treated with different calcium concentrations.   Method  With 1-year-old F. malacophylla seedlings selected as the materials, a research was conducted of the effects of 0 (ck), 25, 50, 75 mmol·L−1 calcium treatments on their leaf morphological indexes, chlorophyll content and enzyme activity.   Result  Different calcium concentrations had different effects on leaf morphological indexes, chlorophyll content and enzyme activity of F. malacophylla seedlings. When treated with different calcium concentrations, with the increase of calcium concentration, all indexes of leaf morphology and structure of F. malacophylla seedlings increased first and then decreased, except for specific leaf length and specific leaf area which increased, whereas leaf number, leaf biomass, specific leaf length, specific leaf area, chlorophyll content, catalase activity and peroxidase activity were significantly different from those in control (P<0.05). When the calcium concentration was more than 50 mmol·L−1, the treatment had no inhibitory effect on F. malacophylla seedlings, indicating that F. malacophylla seedlings responded favorably to medium-low calcium concentration. When the concentration of calcium was 75 mmol·L−1, it inhibited the growth and development of F. malacophylla seedlings, implying that too high a calcium concentration can inhibit the growth of F. malacophylla seedlings. When the calcium concentration was 50 mmol·L−1, the leaf morphological indexes, leaf related indexes, chlorophyll content and enzyme activity of F. malacophylla seedlings reached the maximum, and the growth and development of F. malacophylla seedlings were the best.   Conclusion  The optimal calcium concentration for the growth of F. malacophylla seedlings is 50 mmol·L−1 since too high a calcium concentration inhibits the growth, leaf chlorophyll mass fraction and leaf enzyme activity of F. malacophylla seedlings. [Ch, 1 fig. 2 tab. 28 ref.]
Analysis and evaluation of growth and wood fiber characters of seven poplar clones in southern China
YANG Yan, TANG Jie, LI Yongjin, TANG Yuxi, LI Lei
doi: 10.11833/j.issn.2095-0756.20210481
[Abstract](6) [HTML](6) [PDF](0)
  Objective  With an investigation of differences among wood fiber related traits and their correlation with growth traits among tested poplar (Populus) clones, this paper provides basic information and guidance for the targeted cultivation and selection as well as the utilization of high-quality poplar clones.   Method  Seven poplar clones, including XL-80, XL-86, XL-83, XL-58, XL-75, ZH-17 and I-69 (ck) with straight trunk and large growth were chosen before the principal component comprehensive score method was employed to evaluate the fiber traits of each clone with indexes including fiber length, fiber width, fiber length-width ratio, cellulose mass fraction and cellulose content per plant.   Result  The wood fiber length range of the seven poplar clones was 0.95−1.12 mm, all meeting the standard of intermediate fiber length 0.91−1.60 mm stipulated by the International Society of Wood Anatomy. The length to width ratio of fiber varied from 49.09 to 54.62, which is 63.67%−82.00% of the length to width ratio (30) required for paper making. The cellulose mass fraction varied from 53.06% to 59.66%, exceeding the basic requirement (40%) of paper making cellulose content. Fiber width was positively correlated with height, diameter at breast height (DBH) and biomass but not significantly (P>0.05). Fiber length, fiber length-width ratio and cellulose mass fraction were negatively correlated with DBH, tree height and growth, respectively, but not significantly (P>0.05). Five clones with good traits were selected by principal component comprehensive score method, namely XL-80, XL-58, XL-86, ZH-17, and XL-83.   Conclusion  The five selected fiber clones have integrated the excellent characteristics of each character, which could maximize the utilization of poplar clones and provide more abundant genetic resources for poplar multi-objective breeding. [Ch, 6 tab. 24 ref.]
Effects of light intensity and nitrogen treatments on photosynthetic characteristics of Stewartia sinensis seedlings
ZHANG Tingyu, ZHANG Mingru, LI Qingxiang, ZHAO Nannan, WAN Qi, CAI Yihang
doi: 10.11833/j.issn.2095-0756.20210771
[Abstract](11) [HTML](6) [PDF](0)
  Objective  This study, with an investigation of the differences in the hotosynthetic hysiological and ecological adaptation of Stewartia sinensis seedlings to different light intensity and soil nitrogen content, is aimed to select combinations of light intensity and nitrogen treatment that are conducive to the cultivation of S. sinensis seedlings.   Method  With S. sinensis seedlings used as test materials, efforts were made to set four light intensity gradients, namely full light (L0), light light (44.79±0.51)% (L1), moderate light (19.60±0.23)% (L2), high light (7.25±0.10)% (L3), and three nitrogen application rates, i.e, low nitrogen 0.2 g·kg−1 (N1), high nitrogen 0.6 g·kg−1 (N2) and no nitrogen application (N0) before the light response process, photosynthetic pigment mass fraction and chlorophyll fluorescence parameters were recorded and measured upon 90d treatment.   Result   Light intensity, nitrogen and their interaction displayed significant effects on photosynthetic pigment and chlorophyll fluorescence of S. sinensis seedlings (P<0.05). Chl a/Chl b values of S. sinensis seedlings varied from 2.0 to 2.5, the LSP of S. sinensis seedlings varied from 571.3 to 931.4 μmol·m−2·s−1 whereas LCP varied from 4.8 to 26.0 μmol·m−2·s−1. With the increase of shading degree, the Chl, Car, Fo, Fm, AQY of S. sinensis seedlings tended to increase, the Chl a/Chl b and Car/Chl tended to decrease while the Pmax, Fv/Fo, Fv/Fm and PIABS increased first and then decreased. With the increase of nitrogen application rate, the PIABS of S. sinensis seedlings tended to increase, the Chl a/Chl b, Fo and Fm tended to decrease and the Chl, Car, Pmax and AQY increased first and then decreased; With L1 and L2 light intensity, Pn, Gs and Tr of S. sinensis seedlings were higher and Ci was lower and the application of low nitrogen significantly promoted Pn, Gs and Tr. The Pmax of L1N1 increased by 45.21% compared with L1N0 with the Pn and Pmax of L2N1 being the highest.   Conclusion  S. sinensis seedlings had the best photosynthetic capacity when grown with moderate shading and low nitrogen treatment whereas photosynthetic inhibition occurred with full light or high nitrogen treatment. [Ch, 1 fig. 6 tab. 34 ref.]
Allelopathic effect of water extract of Brassica oleracea var. capitata leaves on seedling growth of Zea mays and Cucurbita pepo
ZHAO Cong, ZHAO Min, HUANG Xuefang, HUANG Mingjing, WANG Juanling
doi: 10.11833/j.issn.2095-0756.20210683
[Abstract](14) [HTML](3) [PDF](0)
  Objective  The objective is to probe the relationship between toxicity of Brassica oleracea var. capitata and stubble obstacles, so as to provide a theoretical basis for establishing a reasonable crop rotation system.   Method  Taking the air-dried leaves of B. oleracea var. capitata as test materials, two crops species (Zea mays and Cucurbita pepo) with relatively high economic benefits and suitable for cultivation in cold and arid area of Shanxi were used as receptor. The effects of water extract from B. oleracea var. capitata leaves with four mass concentrations 0, 0.06, 0.08 and 0.10 kg·L−1 on the nutritional growth of the above two receptor crops were compared by indoor bioassay method, and the corresponding allelopathic effect index and comprehensive effect index were calculated.  Result  When the water extract concentration of B. oleracea var. capitata leaves was ≥0.06 kg·L−1, the growth of roots and shoots of potted Z. mays seedling could be significantly inhibited (P<0.05). The seedling height and root length of C. pepo were significantly reduced (P<0.05) only when the mass concentration of water extract of B. oleracea var. capitata leaves was 0.10 kg·L−1. At the same concentration, the allelopathic inhibition on root length of Z. mays was always greater than that on seedling height. For C. pepo, the allelopathic inhibition on root length was greater than that on seedling height when the water extract concentration of B. oleracea var. capitata leaves was ≥0.08 kg·L−1. When the mass concentration decreased to 0.06 kg·L−1, the allelopathic inhibition on root length was less than that on seedling height. According to the results of allelopathic comprehensive effect index, the allelopathic comprehensive inhibition on C. pepo was less than that on Z. mays.   Conclusion  C. pepo can be used in the rotation system of B. oleracea var. capitata to alleviate the obstacles caused by other toxicity. [Ch, 2 fig. 3 tab. 28 ref.]
Spatial distribution characteristics and influencing factors of forest villages in Zhejiang Province
HUANG Xiaofen, BAI Ou
doi: 10.11833/j.issn.2095-0756.20210558
[Abstract](15) [HTML](11) [PDF](0)
  Objective  This study is to explore the spatial distribution characteristics and influencing factors of forest villages, so as to optimize the spatial layout and understand the forming factors, so as to comprehensively promote the construction of ecological civilization and rural revitalization.   Method  The spatial distribution characteristics of 447 forest villages in Zhejiang Province were analyzed using spatial Gini coefficient, nuclear density analysis and spatial autocorrelation, and the natural and human factors affecting their spatial distribution were explored by Pearson correlation analysis and geographic detectors.   Result  (1) The overall spatial distribution of forest villages was in an agglomerated distribution state, with the characteristics of multi-center clusters of “small-scale aggregation and large-scale dispersion”. (2) The regional spatial distribution was uneven at the level of five major districts and cities, displaying a distribution pattern of “more in the west and less in the east”. (3) In terms of overall spatial density, a dual-core agglomeration area and a dual-core continuous area were formed. (4) In terms of spatial distribution correlation, it showed the spatial correlation characteristics of hot in the southwest and cold in the northeast. The change of sub-cold spot area was small, and the hot spot area changed from strip distribution to strip and sporadic distribution. (5) The spatial distribution of forest villages in Zhejiang Province was affected by topography, climate conditions, river systems, forest resources, cultural resources, socio-economic foundation and traffic accessibility.   Conclusion  Due to the comprehensive influence of nature and humanity, the spatial distribution of forest villages in Zhejiang Province is significantly different. Topography, climate and rivers nurture their ecological environment, while transportation, cultural resources and socio-economic foundations are related to basic conditions, resource advantages and economic support of their development. We should, according to resource advantages, basic conditions and local development policies, adhere to scientific planning, local conditions, coordinated layout and other measures so as to achieve global development, providing high-quality Zhejiang models for the construction of ecological civilization.[Ch, 4 fig. 2 tab. 32 ref.]
Impact of microorganisms of Odontotermes formosanus fungus-combs on the growth of Termitomyces heimii
ZHU Yaning, YANG Guiying, ZHOU Qihuan, XIE Xiaojun, QI Mengwen, SHEN Yi, MO Jianchu
doi: 10.11833/j.issn.2095-0756.20210478
[Abstract](34) [HTML](15) [PDF](2)
  Objective  This study, with an investigation into how Odontotermes formosanus fungus-combs microorganisms influence the growth of Termitomyces heimii, is aimed to provide an experimental reference for further research on the micro-ecology of the termite combs, and make contribution to the artificial cultivation of Termitomyces.   Method  First, oligotrophic medium was employed to separate microorganisms in the fungus-combs. As for bacterium, with an exploration conducted of how bacterial fermentation broth influences the growth of T. heimii, high performance liquid chromatography (HPLC) was used to determine the newly formed soluble carbohydrates in the fermentation broths to clarify the relationship between bacterium and T. heimii. In terms of fungi, co-culture was used to detect the interaction between T. heimii and other fungi in the combs.   Result  Eight kinds of bacteria and 12 kinds of fungi were isolated from the fungus-combs where a large number of spores of T. heimii were distributed. Firmicute separated promoted the growth of T. heimii, under the influence of which, knots were formed in the hyphae and the growth rate of the hyphae partly increased by 0.033 cm·d−1 (P<0.01). By contrast, Proteobacteria inhibited the growth of T. heimii, with a significant inhibitory effect displayed by Burkholderia sp. (undetermined) under the influence of which, T. heimii could hardly grow. As was shown in the HPLC analysis, a large amount of soluble carbohydrates were newly produced in the bacterial fermentation broths, indicating that the bacterium in the fungus-combs had the ability to degrade lignocellulose and convert it into oligosaccharides. Other fungi in the fungus-combs inhibited the growth of T. heimii and once the fungus-combs died out, fungi such as mold quickly occupied the combs.  Conclusion  78.9% of the bacterium isolated from termite combs benefits T. heimii, while all the fungi isolated inhibit its growth, implying that the microorganisms of O. formosanus fungus-combs have a significant effect on T. heimii. [Ch, 5 fig. 2 tab. 18 ref.]
Effects of biochar-based fertilizer and organic fertilizer substituting chemical fertilizer partially on soil microbial abundances and enzyme activities
REN Yi, JIANG Peikun, LU Changgen, SHAO Jianjun, ZHOU Xue’e, CHEN Junhui
doi: 10.11833/j.issn.2095-0756.20210619
[Abstract](27) [HTML](10) [PDF](3)
  Objective  The objective is to provide a scientific basis for improving rice paddy soil quality and for the application of new fertilizer, by investigating the effects of biochar-based fertilizer and organic fertilizer substituting chemical fertilizer partially on soil nutrients contents, microbial abundances and enzyme activities, and investigated the driving factors for soil enzyme activities.   Method  A field experiment was conducted in a typical rice paddy located in Hangjiahu Plain, which soil is Qingzini paddy soil. Four treatments, namely no fertilizer control (ck), conventional fertilizer (CF), biochar-based fertilizer (BF) and organic fertilizer substitution of 50% chemical fertilizer (OF), were laid out with the three fertilization treatments had consistent input of N, P and K amount. The field trail was initiated on June 2019 and soil sampling were collectted on November, 2019. Topsoils (0−20 cm) were sampled to investigate changes in soil carbon and nitrogen fractions, bacterial, fungal and archaeal abundances and enzyme activities involved in C, N and P cycling.   Result  Compared with CF, BF and OF treatments had no effects on soil pH, total C and N, available P and K and nitrate contents, but OF significantly increased soil ammonia and dissolved organic C contents. Compared with ck, OF treatment increased the content of soil microbial biomass carbon (MBC) by 164%, bacterial 16S rRNA gene abundance by 35% and fungal 18S rRNA gene abundances by 98% and fungi/bacteria ratio by 50%, while BF and CF had no effects on them. The three fertilization treatments had no effects on the activities of β-glucosidase, β-xylosidase and Leucine aminopeptidase, whereas BF and OF treatments significantly increased the activities of α-glucosidase (AG) by 111%和136%, β-cellobiosidase (BG) by 77%和100%, β-N-acetylglucosaminidase (NAG) by 109%和177% and acid phosphatase (PHOS) by 97%和199%, respectively. Redundant analysis indicated that changes in soil enzyme activities were strongly dependent on the contents of soil ammonia, dissolved organic C and N, and fungal abundances.   Conclusion  The application of organic fertilizer and biochar-based fertilizer significantly increased soil enzyme activities involved in C, N and P cycling, with the OF treatment further increased soil microbial abundance, which was beneficial for soil nutrient cycling. [Ch, 2 fig. 3 tab. 33 ref.]
Research progress on functional components and biological activities of wild edible vegetables
LI Yaochen, FAN Zipei, YANG Jing, LIU Tingfu, ZHU Biao, ZHU Zhujun, CHEN Xiaoyang
doi: 10.11833/j.issn.2095-0756.20210550
[Abstract](19) [HTML](9) [PDF](0)
There is a long history of use of wild edible vegetables in China. They have abundant functional components, including mineral elements, amino acids, vitamins, polysaccharides, flavonoids and so on. It has important scientific significance and application value to study the basic components of wild edible vegetables for a comprehensive understanding of the nutrients and biological activities. We listed the main nutritional and functional components, summarized the current main research results in the biological activity, including: (1) the content of basic nutrients in wild edible vegetables; (2) the profiles of functional compounds in wild edible vegetables; (3) analysis of active components and efficacy of wild edible vegetables; (4) common methods and technologies to component analysis of wild edible vegetables. Wild edible vegetables are rich in basic nutrients and bioactive substances, including vitamins, phenols and terpenes, which have good activities in antibacterial, antioxidant, antitumor and anti-inflammatory. Future research should focus on functional components and biological activities, and serves as a reference for subsequent development and application. [Ch, 2 tab. 74 ref.]
Effects of light intensity and nitrogen application on photosynthetic physiological parameters of Styrax obassia seedlings
ZHAO Nannan, WAN Qi, ZHANG Mingru, LI Qingxiang, ZHANG Tingyu, CAI Yihang
doi: 10.11833/j.issn.2095-0756.20210605
[Abstract](24) [HTML](9) [PDF](1)
  Objective   This study aims to screen the combination treatment of light intensity and nitrogen application that is more conducive to the expression of photosynthetic physiological parameters, so as to reveal the relationship between the changes of light intensity and nitrogen and the growth of Styrax obassia seedlings.  Method   Potted seedling cultivation method was adopted to construct the two-factor control test of light and nitrogen. Four shading treatments were prepared: all-light control with 100.00% transmittance, light shading with 47.30% transmittance (L1), moderate shading with 20.00% (L2) and high shading 7.75% (L3). Three nitrogen application treatments were included: N2 (0.63 g pure nitrogen), N1 (0.21 g pure nitrogen) and N0 (no nitrogen application). The light response process and the variation characteristics of photosynthetic pigment content were determined and analyzed.   Result   (1)With the increase of shading degree and nitrogen application rate, net photosynthetic rate (Pn), apparent quantum efficiency (AQY) and total chlorophyll (Chl) content of S. obassia seedlings increased, while dark respiration rate (Rd) decreased, and light saturation point (LSP) ranged from 140.00 to 481.33 μmol·m−2·s−1. Light compensation point (LCP) varied from 6.00 to 34.67 μmol·m−2·s−1, and the ratio of Chl a to Chl b was less than 2. (2) Under all light and L1 shading+N2 treatment, the plants died. (3) Under L1 shading, the change of Pn ranging from large to small was N1, N0, and N2. Under L3 shading, when photosynthetic effective radiation (PAR)was greater than 400 μmol·m−2·s−1, the Pn of N2 was significantly higher than that of N0 and N1 (P<0.05). (4) Both light intensity and nitrogen application had significant effects on photosynthetic pigment content (P<0.01), and the influence trend in descending order was light, nitrogen, and light+nitrogen.   Conclusion  The seedlings of S. obassia have strong shade tolerance, and the optimal combination treatment of light and nitrogen is L3+N2. [Ch, 1 fig. 3 tab. 26 ref.]
Rural landscape construction model based on the recognition and evaluation of landscape features
HUANG Yingying, TAN Shizhu, CHEN Qianting, WU Qianqian, SI Nasha, SHEN Yamei, YAN Shaojun
doi: 10.11833/j.issn.2095-0756.20210644
[Abstract](34) [HTML](7) [PDF](1)
  Objective  With an investigation of the characteristics of the the rural landscape, the study is aimed to research its construction model and propose a planning method for optimization.   Method  First, taking Pingyao Town of Hangzhou as an example, with the conduct of rural landscape character identification and comprehensive landscape evaluation and the collection of spatial data and survey information, spatial pictorial representation was carried out of the landscape features whereas the areas were divided using ArcGIS. Then a landscape function evaluation model related to landscape character was constructed to assess the rural landscape featured areas.   Result  (1) Pingyao Town enjoys four rural landscape featured areas, namely, the northern mountain forest ecological and cultural area, the central plain agricultural and cultural area, the eastern plain cultural area and the southern plain wetland ecological and cultural area; (2) Of the four rural landscape featured areas, the northern mountain forest ecological and cultural area (ecological landscape>living landscape>productive landscape) scored the highest, followed by the central plain agricultural and cultural area (productive landscape>living landscape>ecological landscape), the eastern plain area of historical sites (living landscape>productive landscape>ecological landscape) and the southern plain wetland ecological and cultural area (ecological landscape>productive landscape>living landscape).   Conclusion  In accordance with the regional and historical features of Pingyao Town in Hangzhou, four landscape construction models have been proposed: the mountain settlement landscape model, the plain agricultural landscape model, the historical site landscape model and the plain wetland landscape model, which provides a scientific basis for other and further rural landscape construction. [Ch, 4 fig. 3 tab. 25 ref.]
Uncertainty analysis of estimating aboveground biomass of Pinus densata by remote sensing
HUANG Yijie, ZHANG Jialong, HU Yaopeng, CHENG Tao
doi: 10.11833/j.issn.2095-0756.20210473
[Abstract](41) [HTML](8) [PDF](1)
  Objective  To improve the estimation accuracy of forest aboveground biomass, this study is aimed to conduct an uncertainty analysis, trying to figure out the percentage error of estimating forest aboveground biomass by remote sensing and the causes behind.   Method  With factors extracted from remote sensing images and combined with the data of Pinus densata from field surveys, three types of aboveground biomass estimation model were established, namely Multiple Linear Regression (MLR), Gradient Boost Regression Tree (GBRT), and Random Forest (RF), before the uncertainty of sample plot scale and three models was measured and analyzed.   Result  (1) The uncertainty of tree biomass model for P. densata is 16.43%, and the uncertainty of the scale up to the sample plot is 7.07%; (2) The residual uncertainty of the MLR model is 34.86%, the parameter uncertainty is 21.30% whereas the total uncertainty combined with the sample plot uncertainty is 41.45%. (3) In the non-parametric model of the GBRT modeling estimates, the total uncertainty of the aboveground biomass is 23.12%, and the RF is 19.42%.   Conclusion  Among the three remote sensing models, the uncertainty of the non-parametric model is obviously lower than that of the parametric model. Compared with the uncertainty of the sample plot scale, the remote sensing estimation model has a great effect on the accuracy of the aboveground biomass estimation. [Ch, 3 fig. 3 tab. 26 ref.]
Ratio of dominant dust retaining plants in waste dump of desert open-pit coal mine based on CATS model
LIU Qin, YANG Jianying, HOU Jian, TAN Jin, ZHANG Minghao
doi: 10.11833/j.issn.2095-0756.20210604
[Abstract](44) [HTML](6) [PDF](1)
  Objective  The dump of open-pit mine in arid desert regionis easy to produces and (powder) dust and cause air pollution. The purpose of this study is to obtain the ratio of dominant dust retaining plants and species in the restoration community based on the simulation of Community Assembly by Trait Selection (CATS) model, and put forward the vegetation restoration strategy.  Method  A quadrat survey was conducted around the waste dump of Wuhai Xinxing Coal Mine in Inner Mongolia Autonomous Regionin August 2020 to determine the trait values at species and community levels, calculate the target values of functional traits, and substitute the dust retention function and root volume of plants into the model as two factors.  Result  The root volume of plant species was inversely proportional to the dust retention per unit leaf area. The root volume and soil water content was U-shaped. The simulation results showed that the highest relative abundance of each species was Salsola collina and Peganum harmala, with amedian of 0.41 and 0.32, respectively.   Conclusion  To plant S. collina and P. harmala in the dumping site with the relative abundance ratio of 6 to 4 is beneficial to dust detention, which can also explain some mechanical problems in vegetation restoration and provide reference for other studies.[Ch, 2 fig. 1 tab. 40 ref.]
Biocontrol effect of Penicillium oxalicum and Trichoderma asperellum on Ralstonia solanacearum
FANG Qihang, YAN Guzhe, FANG Wei, GAO Jing, ZHAO Kai, JIANG Renqiang, ZHAO Mengli, XU Qiufang
doi: 10.11833/j.issn.2095-0756.20210525
[Abstract](69) [HTML](15) [PDF](3)
  Objective  This study aims to investigate the effect of two biocontrol strains Trichoderma asperellum QZ2 and Penicillium oxalicum QZ8 on Ralstonia solanacearum (bacterial blight for short) With the help of T. asperellum QZ2 and P. oxalicum QZ8 screened by our laboratory, the effect of two biocontrol strains on R. solanacearum was investigated. Hereinafter referred to as the biocontrol effect of bacterial blight.  Method  Using bacterial blight as the target, The the inhibition effect of biocontrol bacteria and their fermentation broth on the growth of bacterial bacterial blight was determined by plate culture method and growth curve method. Soil culture test and dilution coating method were used to determine the inhibitory effect of biocontrol bacteria on bacterial blight in soil.   Result  In plate confrontation culture experiment, test showed that QZ2 and QZ8 had significant inhibitory effects on bacterial blight (P<0.05), with inhibition rates of 80.9% and 45.9%, respectively. The plate culture with high temperature sterilized fermentation broth of QZ2 and QZ8 two biocontrol strains also showed significant inhibition effect on bacterial blight in plate culture (P<0.05), and the inhibition rates of QZ2 and QZ8 on bacterial blight reached were 33.3% and 34.8%, respectively. The fermentation broth on the growth of bacterial blight results showed that the D(600) value of the treatment was significantly lower than that of the control (P<0.05), and the inhibition effect of QZ2 was better than that of QZ8. Soil culture test results showed that the number of viable bacteria of R solanacearum in soil treated by with two biocontrol strains was significantly lower than that of ck (P<0.05).  Conclusion  In this experiment, the biocontrol strains of QZ2 and QZ8, which were extracted independently, had have significant inhibitory effects on bacterial blight wilt, and could can be positioned identified as potential biocontrol bacteria of tomato bacterial wilt. [Ch, 5 fig. 2 tab. 32 ref.]
Distribution range of Tragopan caboti in Wuyanling National Nature Reserve of Zhejiang
WENG Guohang, JIANG Wu, BAO Qimin, LEI Zupei, ZHENG Fangdong, LIU Xi, LIN Lisi, PAN Xiangdong
doi: 10.11833/j.issn.2095-0756.20210456
[Abstract](54) [HTML](21) [PDF](3)
  Objective  This study aims to clarify the latest distribution range of Tragopan caboti population in Wuyanling National Nature Reserve of Zhejiang, so as to provide help for the evaluation of previous conservation work and development of future conservation plan.   Method  Transect survey and infrared camera survey were used to investigate the field distribution in all protection stations in the reserve from 2019 to 2020. Through field investigation and ArcGIS image interpretation, the distribution range of T. caboti was determined by comprehensively analyzing the forest vegetation type, altitude, topography and other related factors around the distribution point.   Result  A total of 69 distribution points of T. caboti were found in Shuangkengkou, Beipai, Huangqiao and Yangxi protection stations, with a distribution area of 24.9, 15.2, 10.7, and 4.5 km2 respectively. The distribution points of T. caboti were mainly in coniferous and broad-leaved mixed forests and broad-leaved forests, and less in other vegetation types. The altitude range was 670−1 550 m, which was wider than the altitude range of 800−1 400 m previously reported. Compared with the core region, the distribution of T. caboti was relatively large in the edge area of broad-leaved forest, and its population distribution showed edge effects. T. caboti-dependent plant Daphniphyllum macropodum was not found in the low altitude and Yangxi areas, indicating that there was no complete correlation between current population distribution and D. macropodum. Among the four distribution areas, Shuangkengkou, Beipai and Huangqiao were geographically connected, and the population of T. caboti might be the result of reproduction and diffusion of the original population in Wuyanling, while the distribution area of Yangxi was distant from Wuyanling, and its population could be identified as an independent population.   Conclusion  After long-term protection, the habitat environment of T. caboti in Wuyanling National Nature Reserve has been restored on a large spatial scale, the habitat fragmentation has been significantly altered, and the population distribution of T. caboti has been greatly expanded, which shows that the conservation measures taken in the reserve for a long time have achieved positive results. Further follow-up research should be carried out on phenomena such as edge effect and scientific countermeasures should be taken in future work. [Ch, 2 tab. 23 ref.]
Plant diversity in various sections of Jinsha River dry-hot valley under different site environments
DU Soukang, TANG Guoyong, LIU Yungen, LEI Chenyu, XU Yingjie, RUAN Changming, SUN Yongyu, ZHANG Chunhua, WANG Yan
doi: 10.11833/j.issn.2095-0756.20210572
[Abstract](81) [HTML](16) [PDF](1)
  Objective  This study is aimed at an investigation of the structural features and differences of the plant diversity in various sections of the dry-hot valley under different site environments so as to efficiently protect and restore the biological environment of Jinsha River dry-hot valley.   Method  With the employment of standard sample plot survey method, a survey was conducted of the plant species richness and diversity of 47 plots in the upper, middle and lower sections of the Jinsha River dry-hot valley.   Result  The plant species richness, diversity and uniformity of the Jinsha River dry-hot valley increased from the upper section to the lower one with the order of species richness being natural forest (20.56)>plantation (12.16)>sparse trees and shrubs (8.00) and no significant difference in diversity or uniformity between natural forest and plantation. The plant diversity tends to increase as the altitude increases with the plant diversity of shade slopes being significantly higher than that of sunny slopes (P<0.05). No significant differences have been found in diversity among the upper, middle and lower sections in the range of 800−1 400 m, while in the range of 1 400−2 000 m, the diversity in the middle section was lower than that in the lower section, but higher than the upper section. The plant diversity in the lower section was always higher than that in the middle section and the upper section of the same slope, and the Shannon-Wiener diversity index and Simpson diversity index in the lower section were significantly different from those of the upper section (P<0.05).   Conclusion  There are significant differences in plant diversity in various sections of the Jinsha River dry-hot valley, with altitude and slope as main environmental influencing factors, and local plantation may increase the plant diversity. [Ch, 1 fig. 4 tab. 27 ref.]
Effects of biochar from different raw materials on microbial activity in heavy metal contaminated soil
SHAO Jia, ZHOU Wenjing, SONG Yao, PAN Yang, QIN Hua, CHEN Junhui
doi: 10.11833/j.issn.2095-0756.20210438
[Abstract](39) [HTML](22) [PDF](4)
  Objective  This study aims to investigate whether biochar prepared from different raw materials can alleviate the stress effect of long-term heavy metal pollution on soil microbial activity, so as to provide scientific basis for biochar remediation of contaminated soil.   Method  Three kinds of biochar prepared from bamboo leftover (BB), Carya cathayensis peels (PB) and Zea mays straw (CB) were added to the long-term lead (Pb) and cadmium (Cd) contaminated soil at a ratio of 3% (biochar soil mass ratio) respectively. The changes of soil nutrients, available mass fraction of heavy metals, soil microbial activity under short-term application of biochar were analyzed.   Result  The addition of three kinds of biochar did not affect the total amount of heavy metals in soil, but significantly (P<0.05) reduced the mass fraction of extractable Pb and Cd in soil calcium chloride (CaCl2). Compared with ck, BB, PB and CB significantly (P<0.05) decreased CaCl2-extractable Pb concentration by 69%, 84% and 72%, and CaCl2-extractable Cd by 26%, 63% and 36%, respectively. PB treatment was significantly (P<0.05) lower than BB and CB treatments. PB and CB significantly increased soil pH (0.79 and 0.51 pH units), soil organic carbon (37% and 74%) and total nitrogen (12% and 41%), respectively, but BB addition had no significant effect. BB, PB and CB significantly (P<0.05) increased the total amount of phospholipid fatty acids (PLFAs) in soil by 33%−56%, gram-positive bacteria by 30%−41%, gram-negative bacteria by 40%−66%, actinobacteria by 34%−52% and fungi by 33%−79%, respectively, but there was no significant difference among the three treatments (except that the total amount of phospholipid fatty acids in PB and CB treatment was significantly higher than that in BB treatment). The three biochar treatments significantly increased the activity of dehydrogenase (2−6 times), but did not affect the soil basal respiration, while PB treatment significantly (P<0.05) decreased the bacterial stress index (13.9%) and increased the substrate induced respiration rate.  Conclusion  PB and CB can be used as a better modifier to decrease heavy metal availability and restore the number and activity of soil microorganisms. [Ch, 4 fig. 3 tab. 29 ref.]
Effects of different rainfall patterns on slope runoff characteristics in the upper reaches of Miyun Reservoir
BI Biao, YANG Jianying, QIAN Yunkai, SHI Changqing, AI Xianfeng
doi: 10.11833/j.issn.2095-0756.20210429
[Abstract](50) [HTML](11) [PDF](4)
  Objective  The objective is to explore the effects of different natural rainfall patterns on runoff process.  Method  According to the quantitative characteristics of rainfall and the concentration period of rainfall peaks, the natural rainfall in the upper reaches of Miyun Reservoir was classified into two levels, and the runoff characteristics under different rain patterns and process rain patterns were investigated.   Result  (1)According to P (precipitation ), t (rainfall duration) and I30 (maximum 30 min rainfall intensity), the rainfall in the study area could be divided into three patterns: P2t3I2 rain (medium rainfall, long duration and medium rainfall intensity), P1t2I1 rain (light rainfall, medium duration and light rainfall intensity) and P3t1I3 rain (heavy rainfall, short duration and heavy rain intensity). P1t2I1 rain pattern had the highest frequency in the study area. The occurrence frequency of the four process rain patterns ranging from large to small was uniform, pre-peak, post-peak, and mid-peak. (2)The runoff characteristics under different rainfall patterns were significantly different. In terms of single rainfall, P3t1I3 had the largest single runoff production capacity, while P2t3I2 had the largest contribution rate to runoff. (3)Rainfall patterns of different processes had significant effects on runoff characteristics, and the rainfall concentrated in the early rainfall period was most likely to produce runoff. (4)Rainfall had the greatest impact on runoff depth. I30 had a great impact on runoff depth, runoff coefficient and runoff depth peak, and the impact on runoff depth peak was greater than that on runoff depth.  Conclusion  The characteristics of slope runoff are highly sensitive to rainfall patterns and process rainfall patterns. Using reasonable rainfall pattern division method to study the relationship between rainfall patterns and runoff can improve the accuracy of hydraulic erosion research. [Ch, 4 fig. 5 tab. 27 ref.]
Ananalysis of the population quantitative characteristics of Carpinus tientaiensis and its associations with other tree species
XU Yuanke, ZHAO Changgao, LIAO Yujun, LIN Jian, WU Chuanbo, WU Chuping, WANG Zhigao
doi: 10.11833/j.issn.2095-0756.20210307
[Abstract](38) [HTML](10) [PDF](0)
  Objective  With an analysis of the population and community characteristics of Carpinus tientaiensis, an extremely small population as well as its interactions with other trees species, this study is aimed to explore its endangerment mechanisms so as to propose workable protection strategies.   Method  Sampling method was first used to investigate the community characteristics in Shangshantou, Jingning She Nationality Autonomous County of Zhejiang Province, and indicators including the importance value, species abundance, distribution of the diameters at breast height (DBH) and inter-specific associations were analyzed.   Result  C. tientaiensis is one of the main dominant species in the community with the largest DBH 74.6 cm, ranking the third in importance value and accounting for 10.6% of the total tree species number, while 17.79% of the total basal area. Individuals with DBH of 1−4 cm and above 30 cm accounted for 90.00% and 66.11% of the total trees in the community respectively, while those with DBH of 4−20 cm only took up 7.91%. Strong inter-specific associations between C. tientaiensis and other species were found by means of association coefficient and percentage of co-occurrence whereas χ2 test indicated that C. tientaiensis was in intense competition against 5 other tree species.   Conclusion  Although C. tientaiensis, is one of the dominant species in the community, it has displayed population regeneration limitation with individuals with DBH at 4−20 cm found, thus faced with strong competition from other species. It was suggested that intermediate felling measures should be taken to reduce the competitive pressure of C. tientaiensis and necessary light environment should be provided for seedling settlement and tree growth. [Ch, 4 fig. 1 tab. 24 ref.]
Restoration characteristics of Phyllostachys edulis community after clear-cutting in Mount Tianmu
CHEN Xu, LIU Zongyue, XU Junjie, QI Xiangbin, YU Shuquan
doi: 10.11833/j.issn.2095-0756.20210595
[Abstract](51) [HTML](13) [PDF](0)
  Objective  The continuous expansion of Phyllostachys edulisin recent years has severely threatened the species diversity and ecosystem stability of the forest. Therefore, the research on the renewal and management of Ph. edulis forest has attracted extensive attention. The purpose of this study is to analyze the dynamic changes of species composition, tree species characteristics and species diversity in the natural restoration process of the community through clear cutting of Ph. edulis forest in Mount Tianmu, so as to promote the protection and restoration of species diversity.  Method  Based on the location monitoring data from 2018 to 2020 in the natural restoration process of Ph. edulis community after clear cutting in Mount Tianmu, the restoration characteristics of plant community, such as composition of family, genus and species, changes of dominant species, the functional characteristic composition of tree species and species diversity were studied.  Result  (1) The species composition was rich and varied sharply: 45 families, 86 genera, and 131 species were found in the arbor layer, 65 families, 137 genera, and 224 species in the shrub layer, and 45 families, 99 genera, and 135 species in the herb layer. Compared with 2018, there was little change in the arbor layer in 2020, but the number of species in the shrub layer and herb layer decreased rapidly, by 54.1% and 65.5%, respectively. (2) The dominant species in tree layer were deciduous species, and the absolute value of the annual average population size change rate of most dominant species exceeded 10%. The dominant species in shrub layer were Theaceae and Rosaceae. The dominant species in the herb layer were Cyperaceae and Gramineae. (3) After clear cutting, community was dominated by deciduous tree species, and the proportion of species and plants in the community was about 80% and 90% respectively. The proportion of species of different growth types and light-tolerant species had little change, but the number of plants of neutral and negative species increased significantly, withgrowth rates of 88.1% and 56.2% respectively. (4) The species diversity of tree layer had no significant difference with time and showed a slight upward trend. Shannon index and Margalef richness of shrub layer decreased significantly, and Pielou evenness increased significantly (P<0.05). Shannon diversity, Simpson Index and Margalef richness of herb layer decreased significantly, but Pielou evenness had no significant difference (P<0.05).  Conclusion  In the natural restoration process of Ph. edulis community after clear cutting, the species composition is rich and the restoration effect of species diversity is obvious. Therefore, clear cutting of Ph. edulis forest is a feasible method to restore and protect biodiversity in National Nature Reserveof Mount Tianmu, and can also be used to improve the ecosystem stability of the spreading area of subtropical Ph. edulis forest. [Ch, 10 tab. 35 ref.]
Floral syndrome and breeding system of Stewartia rostrata
LI Qingxiang, ZHANG Mingru, GU Cuihua, LI Tongpan, WAN Qi, GAO Lei, ZHANG Tingyu, ZHAO Nannan, CAI Yihang
doi: 10.11833/j.issn.2095-0756.20210563
[Abstract](56) [HTML](23) [PDF](2)
  Objective  The objective is to study the floral syndrome and breeding system of Stewartia rostrata, so as to provide a scientific basis for its population renewal, artificial reproduction and garden popularization and application.   Method  Taking 3-year-old S. rostrata as material, the characteristics of pollination biology and breeding system were observed and analyzed by observing the floral syndrome and insect visiting characteristics, measuring the pollen viability and stigma acceptability, and calculating the hybridization index (OCI) and pollen-ovule ratio (P/O).   Result  (1) The flowering period of the population was about 17 days from early May to mid and late May, and the single flowering period was about 2 days. (2) The pollen vitality reached the highest on the day of opening, and the single flower bloomed for 24−32 h , the corolla and stamens were easy to fall off, and the pollen was easy to lose vitality after falling off. (3) The stigma was receptive before flowering, lasting for 7 days. The strong pollen vitality and stigma receptivity had a meeting period of 1−2 days. (4) Stigma was higher than anther in bud stage, and anther was higher than stigma after flowering. Both before and after flowering, stamens and pistils had a certain spatial separation. (5) The OCl of S. rostrata was 4 and P/O was 2 108.0−195 525.0. The breeding system was mainly outcrossing and some self compatibility was required for pollination. (6) Bombus sp. was the main pollinator.   Conclusion  S. rostrata has short pollen life, single pollinating insect, and pollination is easily affected by cloudy and rainy weather, so the reproductive process is greatly limited. The floral syndromes such as centralized flowering mode, large amount of pollen, 5-lobed stigma and long receptive period are the basic manifestations of reproductive success. [Ch, 5 fig. 1 tab. 31 ref.]
Ecotourism consumption behaviors of visitors to Zhejiang Tianmu Mountain National Nature Reserve in the post-pandemic era
MENG Minghao, GU Xiaoyan, CUI Guofa
doi: 10.11833/j.issn.2095-0756.20210356
[Abstract](121) [HTML](34) [PDF](3)
  Objective  This paper, with an investigation of the impact of COVID-19 on the ecotourism consumption behaviors of visitors to Zhejiang Tianmu Mountain National Nature Reserve and an analysis of their ecotourism product preference in the post-pandemic era, is aimed to provide reference for the development of tourism in nature reserves.   Method  SPSS 23.0 statistical software was employed to analyze the significant differences in visitors’ ecotourism behavior and their demand characteristics in the nature reserves before and after the epidemic, the significant differences in their stated preference and revealed preference of ecotourism products after the epidemic as well as the effect of visitors’ stated preference of eco-tourism products on their revealed preference.   Result  (1) There was extremely significant difference in visitors’ tourism frequency and travel time after the COVID-19 outbreak, the impact of which on their channels of information, transportation means and tourist expenses was extremely significant, yet there was no significant impact on visitors’ other ecotourism needs and consumption behaviors. (2) After the COVID-19 outbreak, demographic characteristics of visitors such as gender, age, educational level, occupation and income exerted a significant impact on their stated preferences of some ecotourism products while age, educational level and occupation exerted significant impact on their revealed preference of some ecotourism products of Tianmu Mountain Reserve. (3) Visitors’ revealed preferences are significantly positively correlated with their stated preferences for ecotourism products of the reserve with the stated preferences of biological landscape and natural education exerting more significant impact than those of geological landscape and water landscape.   Conclusion  A series of development countermeasures were put forward to promote the quality of ecotourism products: innovative products were created to drive new tourist needs while intelligent ecotourism products and services were put forward to enhance visitors’ post-tourism experience, especially in sharing. [Ch, 6 tab. 24 ref.]
2022, 39(2): 0-0.  
[Abstract](112) [PDF](35)
2022, 39(2): 1-2.  
[Abstract](122) [HTML](19) [PDF](26)
Relationships among water transport, mechanical strength and anatomical structure in branch and root xylem of Taxodiaceae species
CHEN Sen, LU Shitong, LI Yan, XIE Jiangbo, YE Linfeng, WANG Zhongyuan
2022, 39(2): 233-243.   doi: 10.11833/j.issn.2095-0756.20210248
[Abstract](343) [HTML](84) [PDF](59)
  Objective  This study, with Sequoia sempervirens, Taxodium distichum and T. distichum var. imbricatum in humid regions selected as subjects, is aimed at an analysis of the quantitative relationships among the water transport, anatomical structure, and mechanical strength of the xylem of the branches and roots of the Taxodiaceae species and a discussion of the trade-off between the anatomy and function of the xylem at the organ and cross-species levels.  Method  Targeting the S. sempervirens, T. distichum and T. distichum var. imbricatum grown in Mount Tianmu, Zhejiang Province, with air injection method employed, efforts were made to measure the specific sapwood conductivity (Ks) and cavitation resistance (P50) before the indexes regarding the water transport such as tracheid wall thickness (Tt), pit membrane area (Apm), pit aperture area (Apa), pit membrane diameter (Pd), pit aperture diameter (Ad), hydraulic diameter (Dh)、tracheid density (Nt), aperture opening ratio (Rap) and pit density (Npm) were measured and calculated. Then, the wood density (Dw) and thickness-to-span ratio (Ttob) related to mechanical strength were calculated. Finally, an analysis was conducted of the correlation between water transport and anatomical structure.  Result  The roots demonstrated higher hydraulic conductivity yet weaker cavitation resistance than the branches and Ks in branches of S. sempervirens and T. distichum, and roots of S. sempervirens, T. distichum and T. distichum var. imbricatum was positively correlated with P50, while Ks in branches of T. distichum was slightly negatively correlated with P50 (R2=0.03, P=0.35), showing no efficient-safety trade-off at the organ level. There was a trade-off between Ks and P50 across species, following a negative power function of −2.23 (R2=0.91, P<0.001). There was significant negative correlation between Ks and Dw (R2=0.37, P<0.01), Ks and Ttob (R2=0.20, P<0.01), P50 and Ttob (R2=0.20, P<0.01) in branches of S.sempervirens.   Conclusion  The safety and efficiency of the xylem of the branches and roots of the three plants were all low, and given the different structural requirements for high safety and high efficiency of the three plants, there was no efficiency-safety trade-off at the organ level. [Ch, 7 fig. 1 tab. 48 ref.]
Relationship between xylem structure and function of diffuse-porous and ring-porous wood species in Jigongshan Nature Reserve
HUANG Kaixiang, YU Chongyang, QIAN Hairong, SHANGGUAN Fangjing, TANG Luyao, ZHANG Bona, XIE Jiangbo
2022, 39(2): 244-251.   doi: 10.11833/j.issn.2095-0756.20210628
[Abstract](187) [HTML](41) [PDF](20)
  Objective  The anatomical structure of xylem is the basis of plant hydraulic function and water use strategy. There are significant differences in vessel distribution and morphology between diffuse-porous and ring-porous wood species. The purpose of this study is to compare anatomical structure and hydraulic function of xylem of the two wood species, as well as the quantitative relationship between structure and function, so as to understand the water adaptation mechanism of different wood species.   Method  Three diffuse-porous species (Liquidambar formosana, Salix matsudana, Michelia maudiae) and three ring-porous species (Quercus dentata, Melia azedarach, Juglans cathayensis) in Jigongshan Nature Reserve, Henan Province, were selected to study the branch hydraulic function (specific conductivity, Ks and embolism resistance, P50) and anatomical structure, and the relationship between hydraulic function and anatomical structure was quantitatively analyzed.   Result  Ks of the three ring-porous species was higher and P50 of the three diffuse-porous species was stronger. At the species level, Ks of M. maudiae was negatively correlated with P50 (P<0.05), and there was a tradeoff between hydraulic efficiency and safety. Compared with the three ring-porous wood species, the three diffuse-porous species had higher vessel density, vessel thickness span ratio, smaller vessel diameter and vessel wall thickness.   Conclusion  The ring-porous species tend to significantly improve their water delivery efficiency by increasing vessel diameter to avoid water potential decline and reduce the risk of embolism. The ratio of vessel wall thickness and vessel thickness span in the xylem structure of the diffuse-porous species has important effects on plant water transfer function. [Ch, 5 fig. 1 tab. 32 ref.]
Relationship between hydraulic properties and xylem anatomical structure of subtropical plants
SHANGGUAN Fangjing, ZHAO Mingshui, ZHANG Bona, TANG Luyao, QIAN Hairong, XIE Jiangbo, WANG Zhongyuan
2022, 39(2): 252-261.   doi: 10.11833/j.issn.2095-0756.20210813
[Abstract](136) [HTML](37) [PDF](20)
  Objective  Plant hydraulic system needs to adapt to the changing water environment. This study aims to quantify the relationship between plant hydraulic properties and xylem anatomical structure in different habitats, so as to understand the adaptation strategies of plants to water changes.   Method  Taking 7 species of gymnosperms and 7 species of angiosperms in subtropical zone as research materials, the differences of embolic resistance (water potential with 50% loss of plant hydraulic conductivity, P50), water transport efficiency (Ks) and anatomical structure of plants in different habitats (natural habitat and artificial habitat) were compared and analyzed, and the relationship between plant hydraulic properties and xylem anatomical structure was explored.   Result  (1) In different habitats, Ks of plants in natural habitat was larger, and P50 was smaller. The plant anatomical structure traits had a certain indication of plant hydraulic traits in different habitats. (2) Correlation analysis showed that the conduit hydraulic diameter and conduit density of angiosperms were significantly correlated with Ks and P50 (P<0.05), but the correlations showed the opposite trends in different habitats. The correlation of tracheid hydraulic diameter and tracheid density of gymnosperms with Ks and P50 showed the same trend in both habitats.   Conclusion  It may be common for plants to adapt to relatively arid environment by increasing water transport efficiency in humid areas. The differences in xylem structure and function may be the reason for the differences in plant water strategies in the same habitat. [Ch, 6 fig. 2 tab. 43 ref.]
Construction of diversity index of tree species composition
ZHU Jindi, WEI Xinliang, TANG Mengping, YANG Jingjing, ZHANG Jiyan
2022, 39(2): 262-271.   doi: 10.11833/j.issn.2095-0756.20210171
[Abstract](188) [HTML](24) [PDF](27)
  Objective  This study aims to construct quantitative indicators to quantitatively express the composition characteristics of tree species, which is the technical basis for accurate forest management.   Method  Based on the theory of biodiversity and the characteristics of tree species composition and management requirements, the diversity index of tree species composition (ISCD) was constructed. The variation pattern and basic characteristics of index under different tree species were analyzed by “ten method”. 322 coniferous and broad-leaved mixed forest plots in the inventory of national forest resources of Zhejiang Province were selected as the application objects. ISCD and existing major α-diversity indices were compared.   Result  ISCD covered information on the number of tree species, the relative abundance of tree species and the proportion of tree species in the stand, which not only highlighted the number of tree species, but also fully expressed the uniformity and mixing degree of tree species composition. ISCD could express the changing characteristics of tree species composition completely, independently and effectively. Compared with the major α-diversity indices, ISCD improved the differentiation and sensitivity of tree species, closely evaluated the uniformity and mixing degree of tree species structure, and reasonably and effectively reflected the tree species diversity.   Conclusion  Compared with the majorα-diversity indices, the construction of quantitative index can quantitatively characterize the diversity of tree species composition in a more detailed, comprehensive and targeted manner, and solve the problem that it is difficult to effectively distinguish the composition types of tree species in different stands, such as low richness and high uniformity, high richness and low uniformity. [Ch, 7 fig. 7 tab. 28 ref.]
Construction of compatible individual tree biomass model of Myrica rubra plantation
PENG Jianjian, WANG Zeng, ZHANG Yong, LIU Haiying, GU Guangtong, PENG Xinyi, WU Jiasen, YE Zihao, ZHANG Shen, SHANG Shiyu
2022, 39(2): 272-279.   doi: 10.11833/j.issn.2095-0756.20210272
[Abstract](147) [HTML](36) [PDF](24)
  Objective  The purpose is to construct an individual tree biomass model of Myrica rubra, so as to provide a theoretical basis for sustainable management and accurate biomass estimation of M. rubra plantation.   Method  Based on the data of 48 M. rubra samples and the independent individual tree biomass model established with ground diameter, tree height and crown breadth as independent variables, the compatible individual tree biomass model of M. rubra plantation in Xianju County of Zhejiang Province was studied by using the nonlinear error variable model.   Result  The power function model with ground diameter (x1) as independent variable had the maximal R2, and the models of leaf biomass (y1), branch biomass (y2), root biomass (y3) and total biomass (y0) were y1=0.004x12.795, y2=0.003x13.048, y3=0.002x13.141 and y0=0.010x12.995 respectively. The model with ground diameter as independent variable had the maximal R2 and accuracy, and the relevant parameters of c0, b0, r1, r2, r3 and r4 were 0.084 0, 2.162 7, 0.780 0, 0.779 9, 0.224 3 and 0.204 5 respectively. The distribution law of leaf, branch and root biomass was basically similar with the increase of ground diameter, tree height and crown width. The proportion of branch and root biomass in the total biomass was increasing, while the leaf biomass was gradually decreasing. With the increase of stand ages, the biomass of each component evolved rapidly to branches, roots, and leaves in descending order.   Conclusion  When using the individual tree biomass model of M. rubra with unitary compatibility for estimation, the power function model with ground diameter as independent variable has the largest determination coefficient and estimation accuracy. Ground diameter is the most suitable variable for estimating M. rubra biomass. [Ch, 1 fig. 4 tab. ref. 31]
Influence of environmental factors on distribution of undergrowth species of Pinus tabuliformis plantation in Zhongtiao Mountain
PEI Shunxiang, FA Lei, DU Manyi, XIN Xuebing
2022, 39(2): 280-288.   doi: 10.11833/j.issn.2095-0756.20210323
[Abstract](97) [PDF](10)
  Objective  This study is aimed to quantify the impact of environmental factors on the distribution of species under the Pinus tabuliformis plantation in Zhongtiao Mountain, Shanxi Province so as to provide a theoretical basis for further revealing the maintenance mechanism of species diversity under the P. tabuliformis plantation in Zhongtiao Mountain.   Method  With survey data collected of the plant and soil of different types of P. tabuliformis plantation in Zhongtiao Mountain, an analysis was conducted of the influence of environmental factors on the distribution of species under the planted P. tabuliformis plantation.   Result  The interpretation rates (adjusted explanation rates) of environmental factors on the distribution of shrubs, herbs, and liana species were 45.7% (34.5%), 37.0% (20.4%), and 43.4% (30.6%), respectively. The distribution of species under the P. tabuliformis plantation is mainly affected by abiotic environment. Altitude and soil aeration are the key environmental factors that affect the distribution of species in this area. The distribution of shrubs and lianas under the P. tabuliformis plantation are mainly affected by altitude whereas the distribution of herbs was mainly affected by soil aeration, and the species diversity of the P. tabuliformis plantation declined with the increase of altitude and soil aeration.   Conclusion  The environmental filtering formed by the key shaping effects of topography (altitude) and soil (soil aeration) factors on the regional community habitat are the key factors that affect the distribution of understory species of P. tabuliformis plantation in Zhongtiao Mountain. [Ch, 1 fig. 5 tab. 39 ref.]
Floristic characteristics of seed plants in Qinghai area of Qilian Mountain National Park
JIN Wanzhou, BU Jing, LUO Huiwen, LI Qingshun
2022, 39(2): 289-296.   doi: 10.11833/j.issn.2095-0756.20210343
[Abstract](90) [PDF](9)
  Objective  This study aims to identify the floristic characteristics of seed plants in Qinghai area of Qilian Mountain National Park, so as to provide scientific basis for the protection and utilization of plant resources in this area.  Method  Using the method of route survey and sample survey, the seed plant information was collected, and the floristic composition, dominant groups, characteristic groups, and geographical components were analyzed.  Result  (1) There were 1 058 species (including infraspecific taxa) of wild seed plants belonging to 340 genera and 71 families, which accounted for 75.53%, 61.04%, 42.37% of the total families, genera and species of seed plants in Qinghai Province respectively. Asteraceae and Poaceae were the only big families with more than 100 species, but no big genera with more than 30 species were found. The families and genera were diverse in composition. (2) The dominant phenomenon was obvious, and the characteristic taxa were prominent. There were 10 dominant families, 23 dominant genera, and 8 characteristic families, and 20 characteristic genera, among which 3 families were both dominant families and characteristic families, and 9 genera were both dominant genera and characteristic genera. (3) There were 6 areal types of seed plant families, including 23 families of temperate components, accounting for 67.64% of the total families. There were 13 areal types of genera, and 246 genera with temperate components, accounting for 86.32% of the total genera. (4) Endemic families and genera were poor. There were no endemic families and 10 genera in China. (5) A variety of flora elements intersected, infiltrated and specialized, and were young.   Conclusion  Qinghai area of Qilian Mountain National Park is rich in seed plant species. The geographical composition is diverse and the temperate nature is remarkable. [Ch, 8 tab, 24 ref.]
Effects of stand density and spacing configuration on the non-structural carbohydrate in different organs of poplar
CAO Penghe, XU Xuan, SUN Jiejie, WANG Yuchao, HAN Menghua, GUO Jiahuan, FENG Huili, WANG Weifeng
2022, 39(2): 297-306.   doi: 10.11833/j.issn.2095-0756.20210223
[Abstract](203) [HTML](27) [PDF](24)
  Objective  With an exploration of the effects of stand density and spacing configurations on the non-structural carbohydrate (NSC) of poplar throughout the growing season, this study is aimed to investigate the NSC concentration in various organs of poplar under different stand conditions.   Method  Employing the nested design with density set as the first factor and plant spacing set as the second factor, foliage, branches, stems, and roots of Populus × euramericana ‘Nanlin 95’ were sampled from the experimental stands, in July, their poplar growing season before the soluble sugar and starch in each of them were measured.   Result  The soluble sugar content in the four organs of poplar followed the order of foliage>root>branch>stem during the growing season whereas the starch concentration followed the order of stem>root>branch>foliage. There was a significant difference in the content of soluble sugar among poplar leaves with different densities and plant spacings (P<0.01). The contents of soluble sugar and starch in roots were significantly affected by the spacing configurations (P<0.01), while the influence of stand density and spacing configuration on NSC in branch and stem was not significant and the total NSC content of stand was not significantly affected by stand densities (a comparison between 278 and 400 plants·hm−2), but significantly affected by spacing configurations (P<0.05).   Conclusion  For poplars in northern Jiangsu Province during the growing season, the carbon resources are generally distributed to the parts above the ground with the stems as the primary storage organ. Within a certain density range (278−400 plants·hm−2), the sugar content in poplar leaves would increase with an increase in density. With the same stand densities, the square configuration would be conducive to the accumulation of NSC in poplar organs, which could in turn promote plant growth and stand development, increasing the carbon sequestration potential of the stand. [Ch, 6 fig. 2 tab. 35 ref.]
Selection and validation of reference genes for anthocyanin biosynthesis in Liriope spicata fruits
GAN Sichen, SHI Yue, LIANG Lijun
2022, 39(2): 307-317.   doi: 10.11833/j.issn.2095-0756.20210332
[Abstract](119) [HTML](39) [PDF](18)
  Objective  The objective is to screen the best reference genes (RGs) for the study of anthocyanin biosynthesis in Liriope spicata fruits.   Method  Based on the transcriptome sequence data (unpublished), 15 candidate RGs were selected according to the coefficient of variation and fold change value of gene expression. The expression levels of candidate RGs were determined by RT-qPCR in L. spicata young and mature fruits. The expression stability of these genes was evaluated using software packages and algorithms including ΔCt, geNorm, NormFinder and Bestkeeper. Finally, 10 target genes (C4H, CHS-1, CHS-2, MT, UFGT-1, UFGT-2, MYB-1, MYB-2, MYB-3, bHLH) from 6 gene families (C4H, CHS, MT, UFGT, MYB, and bHLH) were screened to verify the selected reference gene combinations.   Result  There was difference in the ranking of candidate RGs obtained by the 4 methods, so the geometric mean of the 4 methods was used as the comprehensive ranking. Based on geNorm, there were 4 recommended optimal internal parameters, namely CNNM, GPR107, EF1-α and G6PD-2, which were the most stable, while PDP was the most unstable. The standardization verification of the expression levels of 10 target genes showed that there was no significant difference between CNNM and GPR107 as RGs combination and 4 genes as RGs combination, and the correlation coefficient reached 0.999 9. It was more feasible to select the dual RGs combination than 4 RGs combination, while unsuitable RGs (PDP) would cause serious deviation to RT-qPCR results.   Conclusion  The combination of CNNM and GPR107 is the best reference gene for anthocyanin biosynthesis in L. spicata fruit. [Ch, 6 fig. 5 tab. 39 ref.]
Identification and bioinformatics analysis of AQP gene family in Cucumis sativus
LAI Mengxia, DU Changxia, FAN Huaifu
2022, 39(2): 318-328.   doi: 10.11833/j.issn.2095-0756.20210361
[Abstract](223) [HTML](57) [PDF](37)
  Objective  This study aims to explore the functions of aquaporin (AQP) gene family (CsAQP) in Cucumis sativus.   Method  The family members were identified by whole genome analysis, and their protein physical and chemical properties, phylogenetic relationships, selection pressure, gene structure, conserved motifs, cis-acting elements and protein interactions were analyzed.   Result  There were 33 AQP genes in C. sativus genome, which contained 2−5 exons and were unevenly distributed on chromosomes. According to the evolutionary relationship, the AQP gene family was divided into 5 subfamilies. Genome repeat analysis showed that there were 2−3 pairs of gene tandem repeats on chromosome 5 and 6 respectively. The ratios of synonymous substitution (Ks) and nonsynonymous substitution (Ka) of these genes were calculated. The results showed that they were less than 1, indicating that their evolution was affected by purification selection. The analysis of cis-acting regulatory elements showed that most of the elements in the gene promoter region were closely related to hormone regulation, light response, and stress resistance.   Conclusion  Through the whole genome scanning, 33 AQP family members are obtained from C. sativus genome, which belong to 5 subfamilies and map on 7 chromosomes. The upstream promoter region contains stress-related elements, and some genes participate in tandem replication and undergo purification selection. [Ch, 6 fig. 4 tab. 26 ref.]
SSR analysis of genetic diversity of male Torreya grandis
ZHENG Liuhui, ZHAN Liyun, HOU Yu, YU Weiwu, ZENG Yanru, DAI Wensheng
2022, 39(2): 329-337.   doi: 10.11833/j.issn.2095-0756.20210279
[Abstract](227) [HTML](63) [PDF](27)
  Objective  This study aims to analyze the genetic diversity and population genetic structure of 121 individual plants from 5 wild populations of male Torreya grandis using SSR fluorescent markers, in order to provide reference for genetic background, germplasm resource evaluation and elite germplasm screening of male T. grandis.  Method  The genomic DNA of T. grandis was extracted by CTAB method, and the primers were designed. The polymorphic sites of the male T. grandis were detected by capillary electrophoresis using fluorescent primer PCR amplification.  Result  A total of 85 alleles were detected by 24 pairs of primers, ranging from 2−7, with an average of 3.542 per marker, among which the average effective alleles were 1.915. The average Nei’s genetic diversity index and Shannon’s information index in 5 populations were 0.365 and 0.608 respectively. Among the 5 populations, the percentage of polymorphic sites ranged from 75.00% to 95.83%, with an average of 82.50%. The order of genetic diversity of the 5 populations from large to small was Shengzhou, Lin’an, Fuyang, Huangshan and Chun’an. The gene flow among the populations was 4.172, the coefficient of gene differentiation was 0.096, and the degree of genetic differentiation was very low. The results of clustering analysis showed that the genetic similarity coefficient (GS) of the 5 populations varied from 0.865 to 0.978, with an average of 0.932.  Conclusion  The genetic diversity of male T. grandis populations is relatively rich. The genetic variation of the male T. grandis mostly exists within the population, but the gene exchange is also present between the populations. The 5 populations can be divided into 3 groups, which is similar to the results of phenotypic genetic diversity analysis. [Ch, 4 fig. 6 tab. 32 ref.]
Effects of thinning and fertilization on growth and timber structure of mature Chinese fir forest
ZHAO Mingzhen, WANG Liyan, LIU Jing, ZOU Xianhua, ZHENG Hong, FAN Fujin, MA Xiangqing, LIN Kaimin, LI Ming
2022, 39(2): 338-346.   doi: 10.11833/j.issn.2095-0756.20210226
[Abstract](164) [HTML](38) [PDF](11)
  Objective  This study aims to investigate the effects of different thinning retention density and different proportion of N and P fertilizer application on the growth and timber structure of mature Chinese fir forest.  Method  The 27 year-old Chinese fir plantation with a site index greater than 22 was selected, and 9 standard plots were set up by orthogonal experimental design. The thinning retention densities were 300, 600 and 825 plants·hm−2. The application rates of N fertilizer were 0, 100 and 200 g·plant−1, and the application rates of P fertilizer were 0, 250 and 500 g·plant−1.   Result  Excessive thinning retention density limited the diameter at breast height (DBH) increase of mature Chinese fir. Too small thinning retention density reduced the stand stock. Thinning and fertilization could effectively promote the growth of individual tree volume. Higher N application rate could promote the growth of DBH, tree height and average individual tree volume of Chinese fir, and the mixed application of N and P could increase the accumulation of stand volume more effectively. The thinning retention density, the application rate of N and P fertilizer all significantly affected the yield of large-diameter timber of mature Chinese fir forest (P<0.05). The thinning retention density and the application rate of P fertilizer had a significant impact on the yield of large-diameter timber of mature Chinese fir forest (P<0.05), while the application rate of N fertilizer had little impact. Under the site index of 22, the combination that produced the maximum yield and outturn rate of large-diameter timber of mature Chinese fir forest was thinning retention density of 825 plants·hm−2, N fertilizer application rate of 200 g·plant−1 and P fertilizer application rate of 250 g·plant−1.   Conclusion  Under the condition of high site index, the outturn and yield of large-diameter timber of Chinese fir could be effectively promoted by keeping appropriate thinning density and increasing N and P fertilizer application in the cultivation process of mature Chinese fir forest. [Ch, 6 fig. 4 tab. 27 ref.]
Root formation and anatomical structure of Ilex × altaclerensis ‘Belgica Aurea’ stem cuttings
ZHU Xiaoyu, TONG Wanwan, ZHAO Chu, TIAN Ru’nan
2022, 39(2): 347-355.   doi: 10.11833/j.issn.2095-0756.20210283
[Abstract](178) [HTML](53) [PDF](14)
  Objective  This study, with an investigation of the effects of type and concentration of plant growth regulators, soaking time and substrate type on the rootability and adventitious root development of Ilex × altaclerensis ‘Belgica Aurea’ cuttings, is aimed to provide a theoretical and practical basis for the softwood propagation, introduction and domestication of Ilex.   Method  With the semi-lignified stems of I. × altaclerensis ‘Belgica Aurea’, selected as the propagation materials, an orthogonal experimental design of three factors (type and concentration of plant growth regulators, soaking time, and type of substrate) of three levels was applied to research the plant softwood cutting propagation with an investigation of the survival rate, rooting rate, length of longest primary adventitious root and root effect index of the cuttings with various treatments after 80 days since cutting. In addition, NAA was used to promote the root formation of the cutting, with observations made of the external morphological changes of the cuttings. Besides, observations were made of the anatomical structure of the cuttings via the paraffin sections regularly produced with the base of the cuttings. Then, morphological and cytological observations were made of the callus with the scanning electron microscope and transmission electron microscope.   Result  (1) The cuttings soaked in 1 000 mg·L−1 IBA solution for 10 s had a best rootability with significant difference in related index from the other treatments (P<0.01) with an increase of 12.74%−48.83% in the rooting rate. (2) There was no latent root primordia in the cuttings and anatomical observations showed that the plant was considered as bark inductive root formation type with the adventitious root primordia originating from the intersection of pith ray and vascular cambium. (3) The low rooting rate attributed to the 1 or 2 layers of annular sclerenchyma between the cortex and phloem. (4) No root primordia was observed in the callus, whose formation was independent of the adventitious root development, and rooting was not the final result of callus development. (5) There were two types callus types in the rooting process of the cuttings: embryonic callus and non-embryogenic callus. The former were white and closely arranged with the surface cells clustered and distributed in a smaller size, the nuclei being large and the organelles being abundant. The latter were dark yellow with obvious vacuolation and most of the surface cells were not plump or even dead without any organelles observed.   Conclusion  This study has initially screened out the best factor combination for I. × altaclerensis ‘Belgica Aurea’ cuttings, revealed its cutting rooting mechanism. [Ch, 4 fig. 3 tab. 34 ref.]
Construction of endophytic strain bank of seabuckthorn nodule and an analysis of microbial diversity
WEI Jihua, LI Jiayi, LIU Hong, ZHANG Jianguo, LUO Hongmei, HE Caiyun
2022, 39(2): 356-363.   doi: 10.11833/j.issn.2095-0756.20210246
[Abstract](135) [HTML](29) [PDF](18)
  Objective  This study is aimed to conduct an investigation of the microbial diversity endophytic bacteria in rhizobia of Hippophae rhamnoides which play an important role in nitrogen fixation and plant growth and research the construction of rhizobia endophytes.   Method  With the employment of 16S rRNA high-throughput sequencing technology, an exploration was conducted of the relative abundance and diversity of endophytes in Ulange wood rhizobia of Mongolian H. rhamnoides in Dengkou County before the endophytes were isolated and purely cultured to complete the construction of endophytic strains library.   Result  (1) A total of 96 pure culture strains were obtained by traditional isolation, with 4 phyla, 8 classes, 8 orders, 13 families, and 19 genera and Proteobacteria and Firmicutes are of relatively higher relative abundances in terms of phyla classification. (2) With an analysis of 6 groups of samples (M1−M6) consisting of 14 phyla, 34 classes, 89 orders, 148 families, and 314 genera by high-throughput sequencing, Actinomycota and Proteobacteria have higher relative abundance, and the sum of the relative abundance of the two is between 87.50%−97.10% in terms of phylum classification. As for the taxonomic level of the genus, the genus Frankia occupies an absolute advantage with the relative abundance being between 20.12% and 74.81%, and the average relative abundance being 51.49%. With M5 having the largest Shannon and Simpson indexes and M4 having the lowest species diversity, both M5 and M6 have higher levels of species abundance whereas M4 species has the lowest abundance. (3) The results of high-throughput sequencing and pure culture methods are significantly different, especially in the taxa of families and genera.   Conclusion  Both methods reflected the diversity of endophytes in sea buckthorn rhizobia, but the pure culture method could only isolate some endophytes, and it was difficult to evaluate the species composition and relative abundance. Also, high-throughput sequencing analysis could reflect the diversity better and lay the foundation for optimizing pure culture conditions for the isolation of specific species. [Ch, 3 fig. 3 tab. 41 ref.]
Preparation of two strains of lignin-degrading bacteria solid inoculum
LI Yalin, LI Suyan, SUN Xiangyang, HAO Dan, CAI Linlin, CHANG Xiaotong
2022, 39(2): 364-371.   doi: 10.11833/j.issn.2095-0756.20210311
[Abstract](163) [HTML](55) [PDF](11)
  Objective  With two different lignin-degrading bacteria, strain A (Aspergillus nidulans) and strain Q (Trametes sp.) used as materials, this study is aimed to research the production of high-efficiency solid fermentation inoculants for degradation or composting of garden greening wastes.  Method  First, a single factor experiment was employed to determine the types of carbon and nitrogen sources and additional nutrient components of the solid fermentation medium. Then, the orthogonal experiment design was adopted to optimize the amount of carbon and nitrogen sources to be added, based on which, efforts were made to figure out the inoculation amount of additional nutrient components and the best solid medium fermentation conditions of the two lignin-degrading bacteria using a uniform experiment combined with the artificial neural network algorithm.  Result  The optimized solid inoculum medium matrix (mass ratio) of strain Q was with 30.000 g bran as the base, 3.000 g soybean meal powder and 0.188 g corn flour added, with extra nutrients (based on the mass ratio of the matrix) being MgSO4 1.434%, KH2PO4 0.115%, FeSO4·7H2O 1.497% whereas the inoculation conditions being 6.000% of inoculation, with the ratio of material to water as 1.000∶0.992, and the protective agent as 1.000%. The optimized solid inoculum medium matrix (mass ratio) of strain A was with 30.000 g bran as the base, 1.500 g soybean meal powder and 1.500 g sodium lignosulfonate were added, with extra nutrients (based on the mass ratio of the matrix) being MgSO4 0.123%, KH2PO4 0.213%, FeSO4·7H2O 1.280% whereas the inoculation conditions being 21.000% inoculation amount with the ratio of material to water as 1∶1 and the protective agent as 19.000%. Strain Q and strain A were fermented on the optimized medium for 7−9 days to get the largest fermentation biomass with the D(260) value of strain Q being 0.596 and the D(260) value of strain A being 0.478.   Conclusion  The solid inoculum prepared by two lignin-degrading bacteria under optimized fermentation conditions were featured with high biomass and certain potential for degrading the lignin of landscaping wastes. [Ch, 6 fig. 5 tab. 22 ref.]
Resistance of four endophytic fungi to Fusarium sp. of Picea mongolica
JIANG Haiyan, DI Jialin, CONG Lin, YAN Wei, BAI Nana, ZHANG Xu, BAI Hui
2022, 39(2): 372-379.   doi: 10.11833/j.issn.2095-0756.20210287
[Abstract](320) [HTML](77) [PDF](17)
  Objective  This aim is to investigate the antagonistic effect of endophytic fungi of Picea mongolica on Fusarium sp., in order to provide the basis for the development and utilization of biocontrol fungi.   Method  Four strains of endophytic fungi of P. mongolia with strong antagonistic effect were selected as experimental materials, including Alternaria alternata (SDYS36), Fusarium tricinctum (SDYS63), Penicillium chrysogenum (SDYS95), and Aspergillus sydowii (SDYS180), with Fusarium sp. as the target. Using in vitro confrontation and pot experiment, the antagonistm of endophytic fungi against pathogens in vitro and the changes of morphology and related physiological indexes of susceptible seedlings were determined in five groups. The dominant antagonistic strains were screened by significance analysis.  Result  The four endophytic antagonists showed antagonistic activity against Fusarium sp. The antagonistic activity of SDYS180 fermentation broth was the highest, reaching 78.67%. The antagonistic activity of SDYS95 strain was the highest, up to 69.64%, and the antagonistic activity of volatile metabolites of SDYS63 was the highest, up to 16.94%. The four endophytic antagonists showed different degree of antagonistic activity against Fusarium sp. in potted P. mongolica. The plant height, ground diameter and root length of infected seedlings increased by 17.12%, 32.64% and 16.56% respectively by inoculating SDYS180. In the infected seedlings inoculated with SDYS95, MDA content decreased by 5.27%, SP content, POD activity, SOD activity, and CAT activity increased by13.41%, 224.46%, 37.05% and 9.02%, respectively.  Conclusion  Strains SDYS180 and SDYS95 are selected as the dominant antagonistic strains to control seedling blight of P. mongolica. [Ch, 8 fig. 1 tab. 23 ref.]
Driving factors of forest fire and fire risk zoning in Kunming City
ZHU Zheng, ZHAO Fan, WANG Qiuhua, GAO Zhongliang, DENG Xiaofan, HUANG Penggui
2022, 39(2): 380-387.   doi: 10.11833/j.issn.2095-0756.20210339
[Abstract](165) [HTML](31) [PDF](9)
  Objective  With an analysis of the data of fire spots in Kunming City from 2000 to 2015, this study is aimed to determine the main driving factors of forest fires, establish the forest fire prediction model in Kunming City, map the forest fire-risk zones so as to provide reference for the prevention and management of forest fires in Kunming City.  Method  First, with 17 forest fire driving factors selected, a Logistic regression forest fire probability model was constructed on the basis of the satellite forest fire data, including meteorology, terrain, vegetation, artificial, and so on. Then five intermediate models were employed to select the significant variable factors for whole samples before the model was tested using ROC curve. Based on the modeling results of the whole samples, an analysis was conducted of the main forest fire driving factors in Kunming City with the best threshold for probability of forest fire calculated. At last, five fire-risk zones were determined based on the results obtained via the Logistic model.  Result  Among the nine driving factors were altitude, distance from residential areas, distance from railways, NDVI value, monthly average surface temperature, monthly average air pressure, monthly average relative humidity, monthly average wind speed and per capita GDP. The prediction accuracy of Logistic model was as high as 81.7%. The area AUC under ROC curve is 0.905. The best threshold of division was 0.342, the area percent of the five-level fire danger zones were 48.82%, 35.17%, 11.26%, 2.55% and 2.2% respectively.  Conclusion  The main driving factor for forest fire in Kunming City is the meteorological factor with the high fire risk areas in Kunming City concentrated in the southwest region including Wuhua District, Panlong District, Guandu District, Chenggong District, Xishan District and Anning City. [Ch, 4 fig. 3 tab. 22 ref.]
Soil environmental quality investigation and ecological risk assessment of a reclamation land in Jinyun County
ZHOU Yang, ZHOU Wenbin, MA Jiawei, RUAN Zhongqiang, YE Zhengqian, LIU Dan
2022, 39(2): 388-395.   doi: 10.11833/j.issn.2095-0756.20210289
[Abstract](96) [HTML](29) [PDF](7)
  Objective  This study aims to explore the soil environmental quality of a reclaimed land in Jinyun County, Zhejiang Province.  Method  A soil environmental quality survey was carried out in the reclaimed land in Jinyun County in 2020. A total of 17 groups of soil-rice grain composite samples were collected to determine the contents of cadmium (Cd), lead (Pb), chromium (Cr), mercury (Hg), and arsenic (As) in soil and grain. The degree of soil heavy metal pollution was evaluated by single-factor pollution index evaluation method, Nemerow comprehensive index method, potential ecological risk evaluation method and ecological risk early warning index (IER).   Result  The contents of Cd, Cr, Pb, Hg, and As in 0−20 cm soil layer of the reclaimed plot in Jinyun County were 0.33 , 107.74, 53.40, 0.03, and 18.42 mg·kg−1, respectively. Among them, arsenic in 35.29% of the points exceeded the standard, and the other four heavy metals did not exceed the screening value of soil pollution risk of agricultural land. The average contents of Cd and As were higher than the soil background value of Zhejiang Province. Cr and Pb contents in rice at some points of the plot exceeded the national standard. The average value of Nemeiro Comprehensive Pollution Index in the study area was 0.69, and 58.82% of the points in the study area were in the alert range. The geo-accumulation index ranging from large to small was Cd (0.08), Pb (0.01), As (−0.32), Cr (−0.35), and Hg(−3.02). The average value of potential ecological risk index (IR) was 74.10, indicating a slight ecological risk. IER reached the moderate early warning level.   Conclusion  Cr and Pb contents exceed the national standard in rice at some points of the reclaimed land. No heavy metals exceeding the standard are observed in soil at any point, but there exists a certain ecological risk. Cd, Cr and Pb are the main ecological risk factors in the study area, which should be paid more attention to in the future. [Ch, 7 tab. 24 ref.]
Preparation of functional dendritic composite adsorbents and their adsorption properties for Cr(Ⅵ)
SHI Hang, LI Bing, GUO Jianzhong
2022, 39(2): 396-404.   doi: 10.11833/j.issn.2095-0756.20200119
[Abstract](55) [HTML](19) [PDF](5)
  Objective  The objective is to study the adsorption property of dendritic composite adsorbent synthesized by chemical modification of mesoporous molecular sieve for the treatment of heavy metal wastewater.   Method  The composite adsorbent SBA-15-G3 of dendritic compounds was synthesized by chemical modification with mesoporous material SBA-15 as silicon source, and the functional adsorbent SBA-15-G3-SH was successfully synthesized by grafting sulfhydryl onto SBA-15-G3 with thioglycolic acid as coupling agent. The structure and physicochemical properties of the materials were characterized by field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), Zeta potential analysis, and nitrogen adsorption-desorption isotherms (BET). The effects of pH, time, initial Cr(Ⅵ) concentration, and temperature on the adsorption properties were studied through the adsorption of Cr(Ⅵ) in aqueous solution by SBA-15-G3-SH. The adsorption isotherms, kinetics and thermodynamic characteristics of SBA-15-G3-SH adsorbent were analyzed. Langmuir and Freundlich adsorption isotherm models were used to analyze the experimental data.   Result  The Langmuir adsorption isotherm model fitted the adsorption process well, and the adsorption kinetic model accorded with the pseudo second-order kinetic equation.   Conclusion  The adsorption mainly results in the formation of stable compounds through the surface complexation of —SH group on the surface of SBA-15-G3-SH and the electrostatic attraction of heavy metal ions. The thermodynamic results show that Cr(Ⅵ) adsorption onto SBA-15-G3-SH is a spontaneous exothermic process. The high adsorption performance indicates that the SBA-15-G3-SH is an efficient adsorbent to eliminate Cr(Ⅵ) from wastewater. [Ch, 10 fig. 3 tab. 21 ref. ]
Preparation of thermo-sensitive molecularly imprinted hydrogels and their adsorption properties for organophosphorus flame retardants
FANG Tao, LI Jinyun, GUO Ming, WANG Rui, SUN Liping
2022, 39(2): 405-414.   doi: 10.11833/j.issn.2095-0756.20210254
[Abstract](69) [HTML](12) [PDF](1)
  Objective  The objective is to prepare thermo-sensitive molecularly imprinted hydrogels (T-MIHs).   Method  Tris (2-chloropropyl) phosphate (TCPP) was used as template molecule, acrylic acid as functional monomer, N-isopropylacrylamide as thermo-sensitive monomer, N,N′-methylene-bis-acrylamide as crosslinking agent and ammonium persulfate as initiator. The thermo-sensitive T-MIHs was prepared by free radical polymerization. The structure of the raw materials was characterized by infrared spectroscopy, nuclear magnetic resonance spectroscopy, scanning electron microscopy, and differential scanning calorimeter. The specific recognition performance of the hydrogel on template molecules was also investigated.   Result  T-MIHs was successfully prepared and its lowest critical dissolution temperature was 39 ℃. The adsorption isotherm conformed to the Langmuir adsorption theoretical model, and the adsorption kinetics conformed to the pseudo-first-order kinetic model. The molecularly imprinted hydrogel showed a good selective recognition for TCPP, and its adsorption capacity for the template molecule was 119.32 mg·g−1, the imprinting factor α=3.75, the selection factor β=2.75, and the identification of TCPP was temperature responsive.   Conclusion  T-MIHs has excellent adsorption effect on TCPP in aqueous solution, which is of great significance for building thermo-sensitive imprinted hydrogels with high selectivity for organophosphorus flame retardants. [Ch, 9 fig. 4 tab. 30 ref.]
Effect of water on the mechanical performance of OSB in compression tests
CHEN Chaoyi, LI Wanzhao, MEI Changtong, HUANG Helang
2022, 39(2): 415-422.   doi: 10.11833/j.issn.2095-0756.20210291
[Abstract](170) [HTML](31) [PDF](10)
  Objective  Oriented strand board (OSB) is an environmental- and eco-friendly material produced with renewable, mainly fresh wood from logs with either small or large diameter logs. Composed of cross-oriented layers consisting of thin and rectangular wooden flakes or strands that are compressed and bonded together with synthetic resins, it is an important engineered wood product widely applied in load bearing situations and its mechanical performance is largely dependent on the moisture content (MC) and water sorption/desorption. Therefore, with an investigation of the compressive strength (CS) of samples at different MC and water sorption/desorption cycles, this study is aimed to research the effect of water on mechanical performances of OSB.   Method  With samples selected from two types of OSB panels with different thicknesses, conditioned to three different MCs and treated with multiple water sorption/desorption cycles, supervision was conducted of the dimensional changes, CS and strain distribution of samples were monitored. Then the CS was measured using an Instron universal testing machine with the strain distribution recorded using digital image correlation (DIC) simultaneously.   Result  (1) An increase in both MC and water sorption/desorption cycle could lead to an increase in thickness and compressive deformation; (2) The CS of the samples was significantly decreased when they were conditioned with a relative humidity of 95% and a MC of approximately 20%; (3) High MC could reduce the final thickness of OSB after compressing whereas water sorption/desorption cycles could slightly decrease the final thickness of OSB after compressing; (4) High MC and multiple water sorption/desorption cycles were able to change the relationship between CS and displacement from two domains linear to almost linear which attributed to the disappearance of the samples’ plastic deformation domain; (5) High MC can soften wood strands and enlarge internal voids, which could lead to strain increase and the change of strain distribution profile while water sorption/desorption cycles degraded the internal structure of samples and (6) Water sorption/desorption cycles might cause compression strain accumulation in surface layers.   Conclusion  Water affects the CS of OSB in various aspects including the softening of wood strands, enlargement of voids among wood strands, diminishing of trapped stress from hot-pressing with different MCs. Such findings will help with the generation of effective manufacturing strategies that aim at good mechanical performance of OSB at different water conditions as well as optimizing the application methods and extending the application fields of OSB. [Ch, 7 fig. 1 tab. 23 ref.]
Preparation and properties of containing paraffin water based organic wood protective agent
ZHANG Bin, MA Xingxia, ZHANG Jingpeng, JIANG Mingliang
2022, 39(2): 423-429.   doi: 10.11833/j.issn.2095-0756.20210264
[Abstract](121) [HTML](33) [PDF](14)
  Objective  To prevent and control different kinds of wood biohazards, from mold, corrosion, pests to dampness, this study is aimed to develop an organic compound wood preservative containing water based paraffin which is usually classified as emulsifiable concentrates.   Method  First, fungicides complementary in antibacterial spectrum were screened employing the indoor inhibition zone method before they were compound to figure out the optimal compounding ratio. Then with lambda-cyhalothrin (CLT) used as insecticide and liquid paraffin used as the water repellent, the four of them were compounded before the compound preservative was tested for its strength in the control and prevention of mold, corrosion, dampness and pests by means of indoor tests.   Result  A wood protection composition preparation with a mass fraction of 0.20% difenoconazole (DCZ), 0.20% iodopropynyl butylcarbamate (IPBC), 0.02% CLT and 40.00% liquid paraffin was prepared by screening of active ingredients. The preparation was diluted 250 times with water and left to stand for 1 hour without stratification, oil separation and sedimentation. While wood treated with the preparation at 5 times dilution, the content of liquid paraffin in the wood was 49.1 kg·m−3, the waterproof efficiency reached 77.8%. While wood treated with the preparation at 20 times dilution, the content of DCZ and IPBC were 71.2 g·m−3, and the mass loss rate by decay fungi were less than 1.0% and the decay resistance grade reached the strong scored as grade I. While wood treated with the preparation at 5 times dilution, the mass concentrations of DCZ and IPBC in the wood was 0.165 g·m−2, the mold infection value was 0 and resulted excellent anti-mold efficacy. While wood treated with the preparation at 10 times dilution, the content of CLT in the wood was 14.7 g·m−3, the intact value by termite decay was 9.2 with a mass loss rate of 2.6%, showed excellent termite resistance.   Conclusion  The wood preservative developed, when applied after it’s diluted 5−20 times, has displayed a favorable performances in the prevention and control of wood biohazards such as mold, corrosion, pests and dampness. [Ch, 7 tab. 21 ref.]
City-county synchronized assessing and accuracy control of forest ecosystem services
ZHU Chenghao, WANG Jianwu, XIE Binglou, WU Xiaonan, LUO Yibo
2022, 39(2): 430-437.   doi: 10.11833/j.issn.2095-0756.20210328
[Abstract](145) [HTML](62) [PDF](15)
  Objective  This study is designed to explore the application method of accuracy control of volume of forest ecosystem services (FES) by means of city-county synchronized assessing system.   Method  Huzhou City of Zhejiang Province was selected as the research site. By setting up 1 city-level module (CLM) and 5 county-level sub-modules (CLSM), 2 systems of plot data assessing (PDA) and sub-compartment data assessing (SDA) were established based on the continuous forest inventory and forest management inventory to form a city-county synchronized assessing mechanism composed of synchronous accessing mechanism, compatibility mechanism and correction mechanism, so as to complete the volume calculation and assessing accuracy control of multiple FES indicators (water conservation, soil conservation, carbon sequestration, nutrient retention and negative ions provision).  Result  Under the significance level a=0.05, the accuracy of PDA results of each FES indicators at the city level exceeded 90%. Except for negative ions provision, SDA results of other indicators fell into PDA confidence interval. In county-level sub-modules (a=0.05), except for the negative ions provision in Changxing County and Anji County, SDA results of all other indicators fell into PDA confidence interval. Using the correction mechanism, the results of negative ions provision were corrected, and finally the volume and assessing accuracy of 5 FES in Huzhou City in 2018 were obtained.  Conclusion  The city-county synchronized assessing system can control the accuracy of the quality accounting results of FES at all levels, and the final results of regional FES quality can be determined according to whether SDA results fall into PDA confidence interval. [Ch, 1 fig.5 tab. 28 ref.]
Research on vitality characteristics of riverside landscape belt of Shangtang River in Hangzhou based on tourist behavior
WU Jingting, WU Xiaohua, WANG Tianyu, XU Bin
2022, 39(2): 438-445.   doi: 10.11833/j.issn.2095-0756.20210352
[Abstract](174) [HTML](44) [PDF](12)
  Objective  With a history of thousands of years, the Shangtang River in Hangzhou is facing the challenge of insufficient vitality. The purpose of this study is to explore the vitality characteristics of the riverside landscape belt of the Shangtang River, so as to provide research support for activating the spatial vitality of the riverside landscape belt of the canal city.  Method  The landscape space of 8 sample plots [Chengbei Sports Park (A1), Dongxinmen Square (A2), Yongfeng Park (A3), Wangchen Park (A4), Shuiluyuan Site (A5), Qiantaoyuan (A6), Tiandu Park (A7), and Xiyangqiao Park (A8)] in the first-level buffer zone of the Shangtang River were taken as the research objects, and the vitality characteristics of the riverside landscape belt were investigated by behavioral annotation method. The cluster analysis and kernel density estimation (KDE) were used to analyze the survey results.  Result  (1) From the population dimension, the order of population diversity indicators from large to small were A3 A6, A1, A7, A5, A2, A8, and A4, and the behavior diversity from large to small was A6, A7, A5, A2, A1, A8, A3, and A4. The main reason lied in that the waterfront space of A3 and A6 was more diverse and complex, and historical and cultural sites and landscape facilities attracted people to carry out spontaneous activities. (2) From time dimension, the fluctuation coefficients of crowd activities from large to small were A6, A7, A2, A5, A3, A1, A8, and A4. The number of people with activity duration longer than 30 minutes was A6, A1, A8, A2, A3, A7, A5, and A4 in descending order. The main reason was that there were riverside night scenes, cultural activities and perfect supporting facilities in A6 and A1, which attracted people to extend their stay. (3) From spatial dimension, the activity intensity was A6, A1, A3, A7, A2, A5, A8, and A4 in descending order, and the crowd density per unit time period from high to low was A1, A2, A6, A3, A5, A7, A8, and A4. The main reason was that the spatial distribution of the population would be affected by internal and external factors such as spatial boundary, spatial activity area, sense of spatial enclosure, nature of surrounding land, and surrounding population density.   Conclusion  Constructing composite riverside landscape, promoting the integration of multiple spatial functions, tapping the source of landscape and cultural scenery, adding landscape installation sketches, improving infrastructure, creating a vibrant waterfront nightscape, and holding cultural interactive activities are effective measures to enhance the vitality of the riverside landscape belt of the Shangtang River. [Ch, 6 fig. 2 tab. 18 ref.]
Research progress of high-water-holding molding organic cultivation substrate
WANG Yifan, ZOU Rongsong, SUN Xiangyang, LI Suyan, ZHANG Huaxin
2022, 39(2): 446-455.   doi: 10.11833/j.issn.2095-0756.20210313
[Abstract](103) [HTML](36) [PDF](348)
As a main way of soilless culture, substrate culture is widely used in seedling cultivation and production and recent years have witnessed an increasing interest in the research on the production of organic cultivation substrates using agro-forestry wastes. Therefore, the development of high-water-holding molding organic substrates by adding auxiliary materials such as binders and super absorbent polymers is of great significance to the better utilization of agro-forestry wastes as substrate and soil improvement agent. This study, with an analysis of the the development trend of organic substrate and problems existing in its practical application, is aimed to investigate the current situation of water modulation, high-water-holding molding organic substrates and the soil improvement as well as the existing problems and future development trends in order to provide insight for the development of cultivation matrix in the future. [Ch, 72 ref.]
Overview of the methods for sap flow measurement of standing tree based on thermal technology
SONG Bohua, GAO Ge, GAO Shan, SUN Linlin, LI Bingxue
2022, 39(2): 456-464.   doi: 10.11833/j.issn.2095-0756.20210286
[Abstract](166) [PDF](10)
With the comparion of the five thermal methods commonly used for trunk sap flow measurement with the focus on their respective advantages and disadvantages under different research objectives and experimental circumstance, this study is aimed to provide reference for practices in liquid flow measurements of standing trees. Of the five thermal methods commonly employed, Heat Pluse Velocity Method (HPVM) has mainly been used to calculate the flow rate by measuring the time required for the heat pulse to reach the thermocouple. Heat Balance Method (HBM) is used to calculate the sap flow by means of the energy balance between the heat input via the heating element, the heat conduction and the heat carried by the sap flow. Whereas Thermal Dissipation Method (TDM), Heat Field Deformation (HFD), and External Heat-Ratio (EHR) all use the temperature difference to characterize the thermal field changes caused by the sap flow before the sap flow rate and density are determined. In recent years, with the employment of relevant thermal technology, researches aimed to improve the existing thermal technology methods have been rewarded with higner sap flow measurement accuracy of HBM, HFD and EHR. Neither HBM nor EHR has been widely employed due to the complex measurement process and uncertainly in the configuration of the micro external gauge respectively. TDM and HPVM still suffer from low accuracy of determination despite the relatively mature commercial products of them. In conclusion, improperly selected determination methods will lead to great deviation in research rusults, therefore, is it proposed that suitable methods should be chosen in accordance with different experimental conditions so as to better promote the measurement accuracy of tree sap flow. [Ch, 1 fig. 1 tab. 58 ref.]

Bimonthly, Start in 1984

Supervisor:Department of Education of Zhejiang Province

Sponsor:Zhejiang A&F University

Editor-in-Chief:SHEN Xi

Editor:Editorial Department of Journal of Zhejiang A&F University


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