2008 Vol. 25, No. 1
Water miscible hydroxyethyl cellulose(HEC) was modified to increase its fat-solubility by reacting with hexamethyldisilazan. Its synthetic product is trimethylsilyl hydroxyethyl cellulose(TMSHEC). The structure and the surface feature of TMSHEC were characterized by infrared spectra(IR) and scanning election microscope(SEM), the properties were investigated by thermogravimetic analysis(TGA), differential scanning calorimetry(DSC) and mould degradation. The results of TGA and DSC show that the thermal stability and fat-solubility of trimethylsilyl modification cellulose gives rise to a clear improvement. And the mould degradation preliminary experiment proves that the TMSHEC can be biodegraded.
In order to save wood resources, we also use disease-infected pinewoods after killing the nematode and the insect vector in wood. But is the disease will affect pinewood characteristics? This study compared the physical and mechanical properties of healthy wood from Pinus massoniana gathered in 2004 and dead woods that had suffered pine wilt disease and died in 2003 and 2004. Results indicated that healthy wood was significantly greater than dead wood for modulus of rupture(MOR)(PPPPP<0.01) and nail-holding performance(dead wood 65.9%-91.7% less), while there were no significant differences for density. Except of density, dead wood can not compare with the health wood, so we should make a difference between the two woods.
Bamboo-wood composites have been studied widely and deeply, especially in the effects of technological conditions on the mechanical properties. The bamboo-wood sandwich beams are often damaged by bending. With the application of the stress evolution regularity on the perfect elasto-plastic material extension, the plastic areas across the cross section are divided into four steps. And a calculation model of predicting the bending behaviors is presented based on the plane hypothesize. The relations of the theoretic moment and the instantaneous maximum stress across the cross section are analyzed though a case. The theoretical deflections in four stages based on the obtained solution agree well with the available results from experiments, the maximum difference less than 6%. It indicates that the calculation model is effective to predict the ultimate strength and bending deformation, and important to optimize design for structure.
Alnus nepalensis is the oldest species of Betulaceae, mainly distributed in Yunnan Province, which can fix nitrogen. The objective is to study its genetic diversity and assess its resources. In Yunnan Province 58 naturally occurring samples of A.nepalensis were collected from Laifeng, Gaoligong, Jizu, Cang, and Wuliang Mountains. The genomic DNA of A.nepalensis was as extracted by the cetyltrimethylammonium bromide(CTAB) method,and their DNA polymorphism was analyzed by random amplification of polymorphic DNA(RAPD)-polymerase chain reaction(PCR) with 3 optimum primers. A total of 85 DNA bands were amplified, and a DNA molecular UPGMA(unweighted pair group method using arithmetic averages) dendrogram was established. Also, for the samples,Nei's gene diversity and Shannon's information index were computed by POPGENE software Numerical Taxonomy SYStem(NTSYS) software. Results indicated that 64 of the 85 DNA bands(75.3%) were polymorphic, and with the dendrogram A.nepalensis samples were placed into 6 groups with a standard similarity coefficient of 0.68. A.nepalensis possessed abundant genetic diversity with the highest diversity found in the Jizu Mountains. In the Wuliang Mountains genetic diversity of A.nepalensis was richer along the southern slope than the northern. Also, a close relationship between the genetic structure of A.nepalensis and the environment was shown with genetic diversity.
To determine the genetic variation among and within the populations of Ginkgo biloba, 150 individuals from 5 populations that were located in the Tianmu Mountain area(Zhejiang Province), Wuchuan(Guizhou Province),the Dahong Mountain area(Hubei Province), the Jingfu Mountain area(Chongqing City),and the Wuyi Mountain area(Fujian Province) were analyzed using random amplified polymorphic DNA(RAPD) markers with 12 random primers. Data were analyzed with the PopGen32 software and analysis of molecular variance(AMOVA), and compared using the Nei, Shannon, among-population genetic diversity(Gst) indices. RAPD detected 194 loci of which 130 exhibited polymorphism with an average percentage of polymorphic loci(PPB) of 66.7%. Also,the average for Nei's genetic diversity was 0.431 7, for Shannon's genetic diversity information index was 0.621 1, and Gst was 0.288 2. In addition,Shannon's genetic diversity information index revealed a differentiation among populations of 0.190 3, whereas the AMOVA showing differentiation among populations was 36.7%. Overall, RAPD results indicated that the five populations of G. biloba had high genetic diversity with the populations of Tianmu Mountain area, Wuchuan, and Dahong Mountain area possibly being survival habitats stemming from the glacial period.
The researches on gap in temperate zone coniferous forests within mountainous region are little. Through a field survey of 63 gaps in a secondary coniferous natural forest,namely Pinus tabulaeformis forests(19 gaps),Larix principis-rupprechtii forests(26 gaps), and Picea wilsonii or Picea meyeri forests(18 gaps), within the Pangquangou Nature Reserve of Guandi Mountain, Shanxi Province, gap characteristics were analyzed. The canopy gaps(CG) varied from 5.78 to 234.48 m2 and averaged about 60.07 m2. The expanded gaps(EG) varied from 18.49 to 349.68 m2 and averaged about 114.92 m2. Gaps were caused from one or more of these sources:logging, breakage at the trunk, uprooting from blow-down, and standing dead. Most of the gaps were made by 1-4 trees(gap maker). The probability of gap development was greatest when trees forming the canopy were 20-40 cm DBH and 20-30 m tall with most gaps being formed within the last 5-20 years. Also, gap sizes differed greatly in different forest types. Most gap areas in Picea spp. forests were small, but gap areas distributed in Pinus tabulaeformis forests are various.
The inter-specific association modulus of 10 dominant tree species, 10 dominant shrub species,Phoebe bournei and shrub were studied by the correlation analysis of grey systems. The result showed that all the inter-specific correlation modulus of tree were more than 0.5, the inter-specific association modulus between Phoebe bournei and Camellia chekiangoleosa,Styrax suberifolia, Tricalysia dubia, Ilex pubescens, Machilus velutina, Vaccinium carlesii were more than 0.6. The result was in accord with the facts of the real community. It indicated that the study of the inter-specific correlation modulus by grey systems was feasible.
In order to provide basis for soil and water conservation measures, precipitation, throughfall, stem flow, water holding capacity of the litter, and the soil water physical characteristics in a Phyllostachys pubescens stand were measured in Liuxihe Forest Park of Guangzhou City, Guangdong Province from April to August in 2006. Results showed that when throughfall was 267.4 mm:a) canopy interception was 67.6 mm with an interception rate of 25.3%, b) stem flow was 18.1 mm with a stem flow rate of 6.8%, and c) net precipitation under the canopy accounted for 68.0% of the total. The maximum water holding capacity of the litter was 1.406 mm, and the maximum water retention rate was 212.6%. There was a logarithmic regression between water holding capacity of the litter and time of exposure with the relationship between the rate of water absorption for the litter and time of exposure being an exponential regression. Additionally, saturated water held by the soil layer from 0-20 cm was 122.1 mm. There was also an exponential regression for soil infiltration.
The objective of this study was to determine the physiological response from three different provenances(Xinyi of Guangdong Province, Chun'an of Zhejiang Province and Duyun of Guizhou Province) of masson pine (Pinus massoniana) to water stress. Water stress on masson pine seedlings from three provenances was applied using concentrations of 0(control), 100, 200, and 300 g·L-1 polyethylene glycol(PEG6000) for determining the concentrations of soluble sugar, peroxidase activity(POD) and nitrate reductase(NR) activity; and 0(control), 150, 250, 350 g·L-1 PEG 6000 for determining chlorophyll content and membrane permeability. As water stress increased from 0 to 250 g·L-1 PEG, chlorophyll content from each provenance decreased(Xinyi-17.51%,Chun'an-17.69%, and Duyun-14.98%). When treated with 350 g·L-1 PEG, the decrease compared to the control was:Chun'an, 27.27%; Xinyi, 25.70%; and Duyun, 18.21%. As PEG concentration went from 250 to 350 g·L-1, membrane permeability increased obviously. POD increased first and then decreased with the increasing of PEG concentration. When treated with 300 g·L-1 PEG, POD decreased compared to the control with Xinyi decreasing 43.90%, Chun'an 23.99%, and Duyun 27.06%. Compared to no water stress, with 200 g·L-1 PEG, soluble sugar increased for Chun'an(42.78%) and Xinyi(19.49%), while at 300 g·L-1 PEG Chun'an increased 49.01% and Xinyi 37.15%. Also, NR activity decreased with small changes for the Duyuan source but relatively large changes for the Xinyi source. This study showed that drought tolerance in Duyun and Chun'an was stronger than the Xinyi provenance.
By line transect method, we investigated fern resources in a remnant monsoon forest from a valley of the Hongshui River in Guizhou Province, and did cluster analysis to compare this flora with other 12 areas. There were 178 species(including varieties and forms) of fern, which belong to 67 genera in 30 families. The dominant families were Polypodiaceae, Thelypteridaceae, Selaginellaceae, Pteridaceae, Athyriaceae, Aspleniaceae, Aspidiaceae, Dryopteridaceae, and Adiantaceae and genera were Selaginella, Pteris, Cyclosorus, Adiantum, Allantodia, Asplenium, and Colysis. In this area, flora of the fern genera consisted of plants found throughout the world as well as those from the tropical, tropical to subtropical, subtropical, temperate, and East-Asian zones. For those genera that were not spread throughout the world, the 26 dominant genera from the tropical to subtropical zone accounted for 44.83% of the total. The flora of the fern species included those found throughout the world, in addition to those from tropical, tropical to subtropical, temperate, and East-Asian zones along with those endemic to China. Excluding genera that were spread throughout the world, the dominant species were from the tropical to subtropical zone(103 species) and accounted for 59.54% of the total. Additionally, for pteridophyte flora composition, cluster analysis results indicated that this area most closely resembled Nanshan District in Shenzhen, Guangdong Province.
Plantation density is one of the key indices in the management of short-rotation industry material plantation. In order to meet the requirements of investigation on plantation stands, we employed the method of computer-aided simulation, and studied the effects of different centers of circle on the error in the circular investigation of plantation density. Results show that:1) the number of individual trees differs in sample circles with the same spacing and different coordinates, with an evident variation. For the plantation with the same density, the number of trees in the sample circle with the same center also changes under different spacing. 2) in the situation with the same spacing, the mean value of plantation density, using 24 random points as centers of circle, could present the fact. 3) for the sample circle with a designed spacing of 1.50 m×4.00 m and 2.00 m×3.75 m, the optimum coordinate of the center of circle is(0, 0) m. 4) for the spacing of 2.00 m×3.00 m, the optimum coordinate of the center of circle is(1.5, 0) m. 5) for the planting spacing of 1.20 m×5.00 m, the optimum coordinate of the center of circle is(0, 1.0) m. 6) for the planting spacing of 2.00 m×4.00 m, the optimum center of circle is located in the middle of two neighboring rows with a coordinate of(0, 2.0) m.
Taxus chinensis var. mairei is a unique Chinese species designated as a national level key protected plant. In this research, for the first time, ex-situ conservation and cultivation techniques in a series of trials with direct seeding, cuttings, transplants, and colonization were conducted in December, 1999 with T. chinensis var. mairei on Zhoushan Archipelago. Results showed that seedling growth had an annual average height of 18.9 cm and base diameter 0.32 cm, while with certain technical measures maximum height was 35.0 cm and base diameter was 0.50 cm. With intermittent spray in a canopy covered with shading nets, five-year-old seedlings from cuttings and direct seeding achieved a rooting rate of 90%; however, using ABT 1 rooting powder (a high efficiency plant growth regulator), it was possible to attain 100% rooting. Propagation of transplanted container seedlings in a greenhouse also achieved favorable results. In steady-wind-speed region with a thick soil layer, six-year-old saplings reached an average height of 2.30 m and base diameter of 5.42 cm with an average diameter at breast height of 2.37 cm; the average crown width from east to west reached 2.42 m and from south to north 2.15 m.
With the fixed spot test method, the growth and economic evaluation of Eucalyptus urophylla×E. grandis clones DH32-28 and DH32-29, E. grandis×E. urophylla clone GL-9 in Guangxi Province were compared with that of E. urophylla clone U-6 which was introduced from Guangdong Province. The results showed that DH32-28,GL-9 and DH32-29 had obvious growth advantages on per unit area yield of stock, the wood income and profit. These three clones would be the best choice for Eucalyptus plantation.
To determine combustibility of Schima superba, the Fire Proceeding Index of S. superba fresh leaves (squares with 0.5, 1.0, 1.5, and 2.0 cm sides as well as the whole leaf) under different intensities of radiation(40, 45, 50, 60, and 70 kW·m-2) and processing modes was tested using a cone calorimeter and outer ignition probe into the testing methods. Data Processing System was used to test discrepancies in the fire proceeding index. Results showed discrepancies with two different treatments that were obtained from S. superba leaves. Comparing the different radiation intensities and the different leaf sizes, we found that the Fire Proceeding Index was significantly greater with a radiation intensity of 40 kW·m-2 and leaf sizes of both 0.5 cm and the whole leaf.
Forest fire is a great threat to forest resources of China, so we should strengthen preventing and fighting fire,and we also should do assessment algorithm after forest fire. The technique of forest fire assessment was studied from the geographical information technology. The paper analyzed the graph element segmentation, graph element intersecting, and graph element proportion calculation to find out the amount and proportion of the fire disaster. The paper had a quantitative analysis of the fire area and fire loss to establish a GIS-based forest fire assessment technique.
Stand visualization is difficult, because the structure of forest is very complex and various. The existing software include SmartForest, stand visualization system(SVS), EnVision and Visual Forest, but they are not perfect. We want realize stand visualization based on ArcView, which is geographic information system(GIS) software, in order to provide technical support for nature reserve protection, restoration and reconstruction. A typical plot of 100 m×100 m in conifer broadleaved mixed forest of Tianmu Mountain National Nature Reserve, was investigated with adjacent grid, research instrument including total station, steel tape and increment borer were used to get spatial data and attribute data of each tree. First, coordinate transform of spatial data were taken in ArcView. Then, the digital elevation model(DEM) was established. Practice proved that the terrain which created through inverse distance weighted interpolation(IDW) and triangulated irregular network(TIN) model was good. The real tree photos were dealt with Photoshop to draw the tree symbols and realize the tree visualization by loading trees symbol into ArcView. Finally, stand visualization was realized.
The aim is to simplify calculations of measurement adjustment and create points' files in computer assisted search service(CASS) automatically. In this study, visual basic for applications (VBA) and component object model(COM) codes were embedded into Microsoft Excel. Calculations of adjusted measurements were simplified and point files in CASS were automatically created. With this method, first COM modules with angle converts and CASS points using an active template library(ATL) template from VC were developed. Then, COM modules were used with VBA code in Excel so that measurement adjustments were calculated and point files were automatically created. This method was used for topographic measurements from 1:500 large-scale maps in the digital botanical garden of Zhejiang Forestry College with 25 points being rapidly calculated by adjustment of a closed traverse. Results revealed nearly 12 000 point files that were created automatically and accurately. With this method, complex calculating procedures were not necessary, unlike before when manually performed, and when creating the point files, mistakes were rarely made. This study showed that adjusted calculations of a closed traverse and automatic creation of point files, was relatively easy.
With the deepening contradiction between woods supply and demand, the forest reserves become scarcer. It's very significant to study how to cultivate sustainable development of homeland forest reserves enterprise. Three listed forest companies were their typical representatives. The paper analyzed the financial indexes of Jilin Forest Industry Co. Ltd, and compared the results with the other two listed forest companies,hence finding the solutions and conclusions on the sustainable development of the forest reserve enterprises. The problems were as follows:current ratio and profitability index were coming down; asset-debt ratio was too low; and the selling cost and management cost were increasing. The deep reasons were as follows:fierce competition led to competition deficiency in product marketplace; the project to protect the natural forests led to the decreasing income of selling wood; the state-held share led to owners' vacant place; there were problems in the company governance. The proposals and conclusion were as follows, the stock amounts of forest reserves was the key factor affecting the future development of the enterprise; the enterprise should improve the marketplace competition by various innovations, readjust the product structure in time based on the marketplace and policy, and optimize company governance structure by reforming stock right and incentive mechanism.
Taking Qili township of Kecheng district, Quzhou City, as an example,the functions of rural tourism via questionnaire survey were analyzed, thorough field survey and review of related data. Results indicated that rural tourism has various functions, including economical,environmental and social-culture functions. But rural tourism also had many problems and challenges such as the limited contribution to the tourist industry chain, pressure on the environment during the tourism seasons, the "urbanization" of rural scenic spots, the disappearance of rurality and the fierce competition of the tourism market. The author suggested the functions of rural tourism should be analyzed dialectically and the negative functions should be tackled.
Chinese classical garden is a space art which is mostly perceived through vision. Acoustic beauty is the highlight of the Chinese classical garden. Acoustical factors are essential to achieve the tranquility of the Chinese classical gardens. In the art of Chinese classical garden, hearing and vision are usually interwoven. Various factors include artificial factors can achieve acoustic beauty. Acoustic beauty is also very important to the modern gardens.
Almost all crops have been studied on QTL(quantitative trait loci) mapping with many QTL mapping methods, such as IM(interval mapping), CIM(composite interval mapping), MCIM(mixed-model based composite interval mapping) and Bayesian QTL mapping having been developed. However, these methods have had shortcomings, namey, the genomic region of the QTL detected, within which there were probably hundreds of candidate genes was still too large. In this paper, a better understanding of the molecular functions of QTLs was obtained by first briefly reviewing methods of analyzing the candidate gene within QTL intervals based on bioinformatics. Then, in order to provide a new analytical method for better use of QTLs in the future, the genetics, genome organization, gene expression and function of candidate genes located on QTL region were analyzed.
In order to promote the development of wildlife domestication and propagation in Zhejiang Province,we made an investigation on the actuality of the wildlife institutions in the whole province from April 2006 to March 2007. There are 276 institutions for the wildlife domestication and propagation, which breed 360 species and 3 210 853 animals. Among them,18 institutions are for ornamental animals, sweeping all the species,and 257 institutions are for edible animals, in which the species are no more than 1/3 of all. Hangzhou, Ningbo and Jinhua City have a 54.34% proportion in the whole province's breeding unit gross. There are 15 species which have more than 10 thousand livestock individually,including Chinemys reevesii, Rana tigrina rugulosa, Rana spinosa, Cervus nippon and so on. The investigation shows that there is great development potential in the wild animals' domestication and propagation industry,so we should increase the species which we already have a mature domestication and propagation technology, enhance the management for the institutions, and spread the technologies in the developing areas..
According to the results of the fieldwork in Wenling City, there are 374 species (including varieties) of ornamental pants which belong to 307 genera of 122 families, accounting for 21.1% of the total species of vascular plants in Wenling city, 35.2% of the total genera and 62.6% of the total families. They could be classified into 11 groups by their usages, namely, garden trees, courtyard trees, street trees, hedge plants, vertical landscaping plants, potted plants, parterre plants, cut flowers, aquatic plants, law plants and groundcover plants. The ornamental plant resources in Wenling City are characterized by richness and having special and rare plant species.
The soundness of Nanjing linden(Tilia miqueliana) seeds was low and the species had an obvious periodicity of seed bearing. Upgrading by artificial method was benefit for seed and seedling production. Soundness of the Nanjing linden seeds was measured with soft X-ray photography utilizing a voltage of 25 kV, an electric current of 3 mA, an exposure time of 10 s, and a photographic flange-focal distance of 25 cm, to produce a radiographic image that accurately distinguished the full seeds, incompletely developed seeds, and the empty seeds on No.2 plastic coated photographic paper. The results of water separation for Nanjing linden seeds were checked using X-ray technology. It showed that the sound seed rate selected by soaking seeds in water for 14 h was 87.8%,and the sound seed rate selected by soaking seeds in water for 26 h was 85.0%. The sound seed rate of sunk seeds after soaking them in water for 76 h was still higher than average sound seed rate. This study confirmed that the method with integrated soft X-ray photography and water separation could be used for upgrading Nanjing linden seeds. The efficiency of selection was high and the sound seed rate of selected seeds using above method exceeded 85%.
The clump structure affected the growing environment of bamboo directly. The relationships of initial culm number per clump, spatial distribution of culm and culm number per clump with the culm morphological variation of Bambusa ventricosa were studied. The results showed that abnormal rate of new culm decreased with increasing initial culm number per clump and time. The suitable culm number per clump was 2-3. The number of new bamboo outer and inner clump was correlated negatively and positively respectively with culm number per clump after shooting. Abnormal rate of new culm was negatively correlated with culm number per clump after shooting. Abnormal number of new culm decreased with increasing of culm number per clump before shooting; abnormal number of new culm was negatively correlated with culm number per clump before shooting. The suitable number per clump should be 4-6 in operation.
The rhizome of Atractylodes macrocephala is famous medicinal material. ‘Zheshu No.1’ and ‘Zheshu No.2’ are new cultivars chosen by the Zhejiang Forestry College and the Traditional Chinese Medicine Institute of Pan'an County. A regional experiment in southern, northern, and central Zhejiang Province on ‘Zheshu No.1’ and ‘Zheshu No.2’ cultivars of Atractylodes macrocephala was carried out in both new and old rhizome producing areas of Wenchen,Xinchang, and Anji Counties as well as Shengzhou and Lin'an Cities. Every field area of 12.5 m2 were planted 200 plants in March with three replication for one cultivar in one county or city. The local cultivars were as the control. Analysis of variance with main plots as cultivars and sub plots as sites was used to analyze three important features:survival rate, rhizome production, and rate of superior formed rhizome. Interaction between cultivars as well as between cultivars and sites were all significant(P<0.01). ‘Zheshu No.1’ could be introduced to these cities and counties for popularization experiments, whereas the properties of ‘Zheshu No.2’ were poor.