1997 Vol. 14, No. 1
The results of study on the various indices of 7 provenances showed that the root s ageing of some seedling from Jinyun and Daiyunshan affected the surival rate. The 7 provenances were divided into 5 groups: Lin an-Jinyun, Huang shan-Kaihua, Jinzhai, Daiyunshan and Tiantai. The seedling growth in stem mainly started in the earlier stage, while its growth in conifenous and root in the middle and later stege. The closing degrees of gross increment of provenance and the variation were inconsistent. The regulation rhythm of cell membrane and the cluster result of 7 provenances were consistent in the middle period. The variable rhythm of membrane permeability directly was influenced by the closing degree of variation, when the outside permeation of the elect rolytes of 7 provenances at 30℃ increased. Kaihua provenance had a stronger power of controlling the permeation. The range of quantative change of nucleic acid was greater than that of RNA. According to the comparison of DNA a nd RNA, Kaihua was in the maxmum position, and Lin an in the minimum posi tion. Major factor for the grouth of seedling root was the generaring quantity of RNA. The ulilization power in CO2 of Jinyun and Tiantai was much stronger than that of Kaihua, Huangshan, Jinzhai, Daiyunshan and Lin an, which could be considered as a basis for the initial separation of seedling stage of pine provenance.
Eight plantation trees (20 to 26 years old) and 2 natural forest trees (54 and 55 years old) of Masson pine were collected in Forest Farm of Jingshan County, Hubei Province. Tracheid lengths in radial direction first gradually increased and then levels off from pith to bark. It decreased along the stem height. So did the variation in tracheid lengthwide ratio. Basic density at the pith was bigger than that at the bark, and it firstly descended from pith to bark, then gradually asended and finally leveled off. It longitudinally descended from base to top. Cellulose content increased from pith (38. 57%) to near bark (46. 98%) in 22 years old trees. Lignin, pentosan and benzen-alchol extractives contents decreased from pith (28. 35%, 14. 32% and 6. 60%) to bark (24. 70%, 10. 24% and 1. 22%). The juvenile period of the wood was about 14 to 18 years old. Before the period, the tracheid length, length-wide ratio and extracted basic density in trees of natural forests were greater than those in those of plantations. After the period, the results were right converse. Based on variations in the whole tracheid morphological features, basic density , wood chemical composition and the tree growth properties, the range of mature ages for pulpwood were from 15 to 30 years old.
The tolerance to NaCl of tissues culture calli of Populus clones (NL-80105, NL-80106, and NL-80117) and Pinus elliottii was studied. The results were as follow s: (1) MS medium with 2.0 mg kg- 1 of 2, 4-D and 0.5 mg kg- 1 KT was suitable for tree calli in tissuecul tures; (2) the salt tolerances of calli from roots, stems and petioles were different on MS containing NaCl. The calli with the highest salt to lerance was from stems; (3) the salt tolerance of subculture calli of Populus clones was higher than that of Pinus elliottii, which was in keeping with the salt tolerance of Populus and Pinus elliottii trees.
In the present paper, the dominant groups, microenvironment distribution, perpendicular distribution, community diversity and resembling of the insect fauna in Baishanzu Nature Reserve are analyzed and discussed, according to the resulting of the expedition carried by the Insect Scientific Expedition to Baishanzu in 1993～1995.
A plantation of Masson pine (Pinus massoniana) provenances and other pine species was planted in 1984 in the suburbs of Nanjing. Of the plantation 135 trees of 39 Masson pine prov enances and 6 other pine species were inoculated with Bursaphelenchus xylophilus collected from the dead trees of Masson pine in July of 1995, inoculating about 5 000 per tree. The resistance and process of susceptibility in different Masson pine provenances and other pine specics to the nematode had a great variance. Five Masson pine provenances from Gaozhou, Yingde and Xinyi of Guangdong, Xincheng of Guangxi, and Yuanan of Hubei had more resistance than other provenances, Pinus thunbargii and P. serotina, but less than P. elliottii, P. taeda, P. echinata and P. rigida. Masson pine resistance to the nematode was weakened along with provenance latitude from south to north.
The Chinese fir cones were mainly harmed by three diseases, i. e. Botrytis cinerea, Pesealotiopsis apiculatus and Giomerella cingulata, and three pests, i. e. galls in Chinese fir cones, Dichomeris sp. and Sinorsillus piliferus. There were obvious variances between the resistances of the cones in different clones. Two clones, Longquan 20 and Kaihua 0, could resist the damage of diseases and pests, and Linan 131 was sensitive to diseases and pests. Mortality rate of cones at the north of crowns was obviously higher than that at the other directions.
The distribution of actinomycetes in soils supporting 5 forest communities and its relationship with soil properties were ana lysed. The results showed that: 1. Sig nificant differences in distribution of groups of streptomycetes existed between 5 communities. The number and the groups of streptomycetes were most abundant in the soil under the forest community of Phoebe zhennan. 2. Each groupof streptomycetes in soil had its spectrum in different forest communities. The groupscomposition and the dominant groups of streptomycetes varied with different forest communities. 3. The distribution of actinomycetes was positively correlated with properties of soil fertility, and was affected by soil fertility.
The natural psammophytes on the islands in Zhejiang can be divided into 5 vegetation types (namely broad-leaved deciduous forests, bamboo groves, broad-leaved deciduous brushes, broad-leaved evergreen brushes and meadow), 11 formation groups, 21 formations and 5 annual communities. In this paper, the ecological environment, distribution, physiognomy, structure and composition of main formations are described for the first time. Finally, some views about protection, exploitation and application of the vegetations are advanced.
This paper describes the characteristics of micrometeorological parameters in the plastic green house tea plantation and their effect on plucking date, yield and output value of high quality Longjing tea. The results indicated that compared with those in the control tea plantation, in the plastic green house tea plantation, mean air temperature, maximum air tempera ture, minimum air temperature, mean air relative humidity and minimum relative humidity were increased in the plastic green house tea plantation. The relationship between mean air temperature, relative humidity in the plastic green house tea plantation and mean air temperature, relative humidity in the control tea plantation were calculated by a set of regression equations. Compared with that of control tea plantation, the plucking date of plastic green house tea plantation was advanced 10～15 days. The yield and output value of high quality Longjing tea in the plastic green house tea plantation increased 17%～35% and 103% ～160% respectively compared with the control.
By setting two major wood producing counties of Suichang and Lin an as their researth centres, the authors analyze the reasons why it is difficult to fulfil the wood purchasing policy. The key reasons are that: the unreasonable distribution of forestry profits, the lack of necessory management measures in forestry improvement, the bad management of the wood company. It is advanced that the current wood purchasing system should be improved, the forestry taxes should be adjusted, the management of forest administ ration should be strengthened and the management system of wood company should be changed so as to fufil the wood purchasing policy successfully and quickly.
The status quo of forestry in China is the following: inadequate forest resources, decline in forestry quality; worsened ecological environment , frequent natural calamity; lower level in utilization of forestry resources; lack of reasonable compensation mechanism in forestry; backward development of forestry market. After analysing the status quo, combining the utilized history of forestry resources, the inevitablity of sustainable forestry and its main objectives are pointed.
In recent years, the nursery stocks and trees of Japanese sweet kaki persimmon hav e been seriously damaged by a nthracnose at Quxian Forest Farm of Quxian County, Zhejiang Province. The disease leads to stocks and twig swithered, blossom and fruit drop added, quantity and quality of stocks and fruit cut down. The disease starts to occur during late April to early May, lasting for mature period of fruits. Its incidence rate is related to air temperature, humidity, precipitation and rainy days. Heavy rainfall and long rainy days causes serious infection. On the contrary, high air temperature and low humidity do not. During periods of infection, control could be made by spraying tree crowns and stocks with 100-fold solution of bordeaux mixture, 1 000-fold chlorthalonil 75 wp and 600-fold mancozeb 50wp, resulting in efficiency of 89. 3%, 83. 4% and 85. 7% respectively.
Definite divisions were made about the developing stagesof Chinese fir seeds and about the periods in which hollow, kernel and woody seeds formed in embryo abortion. The causes resul ting in hollow, kernel and woody seeds were analysed in heredity, self-infertility, bad climatic factors, and biochemical components in comparison between woody seeds and good seeds. High ratio of woody seeds, a complex problem of cone embryonic development, was related to heredity, pollination and environment.
Based on the comprehinsive investigations on natural resources of Jiulong shan s mountain areas, the authors propose an exploitation and utilization programme for all aspects of the rich natural resources with the prerequisite of natural conservation in order to prosper the mountain economy. The measures aims at exertion of superiority of forest resource. The processing industry of forest products, cultivation, wildli femanagment, tourism and the third business should be developed immediately. The exploitation objectives, sequences and measures are also discussed in the article.
Cultivation technology for large leaved Lycium chinense was summarzed on the basis of studies on its cutting and growth habits with 8 cm hard cuttings performing best. Fertilizers and water had a considerable influence on the growth so that sufficient basal dressing before cutting was done, postharvest application of quick-acting fertilizers and foliar spray of 0. 3% urea solution at an interval of 7～10 days were recommended, so was putting up a shed over the cutting bed to avoid damage caused by high temperature. Young shoots and leaves could be harvested when the plant was 30～40 cm tall with the 1. 0～2. 0 cm of basal stem above the ground left behind in the bed for further sprouting. The barvest season was from early May to late October, during which 7 times of harvesting were there. In late November the cut plant was kept in the same bed or covered with earth for overwintering .
By means of suitable processing technologies for young ferns collected from forest lands, several fern vegetables, such as canned fern, sweet and sour fern, vinegar-pepper fern, spiced fern and quick-frezen fern, etc. , could be producted. The test showed purple-brown ferns were good for these vegetables.