The oil content, the composition of fatty acid, the iodine number and the coarse protein content of 58 Camellia spp. from 21 districts were zanalyzed.It shows that there is a significant positive correlation between the unsaturated fatty acid content and the latitude (r=0.6934) and a trend of negatire correlation between the protein content and the rainfall in August and September in C. oleifera Abel selected from 14 districts by means of multiple linear progressive regression analysis. In addition, the result of quality correlation analysis indicates that there is a negative correlation between the unsaturated fatty acid content and the protein content. It was also found that the bigger the fruit is, the less it contains unsaturated fatty acid among different species.

According to geographical and floristic components of forest,the floristie composition,properties and origin of the moist evergreen broad leaf forest at Xujiaba have been discussed emphatically in this paper. It was shown that this forest floristics was mainly consisted of Sino-Hima-layan, characterised by the endemic species in southeast of China,and comprised together with the north border component of tropical south eastern Asia (Indo-Malasia) in the shape of shuttle shown in its diagram of vertical structure,and also had a character of ancient origin. In addition,it had a closer relation with the south of Sino-Himalayan mountain forest and north of tropical southeast Asia,which had 5 layers and eight kind of synusia. Therefore,Xujiaba forest was the typical evergreen broadleaf forest at the top of the subtropical mountain vertical belt despite of the difference in ecological environment from other same mid mountain moist evergreen broadleaf forest.

The results obtained from this study indicate that a kind of very fertilized soil named limestone soil, can be evolved from the parent rock of limestone under the interactions of northern tropical climate and vegetation condition, which is abundant in organic matter, nitrogen and other nutrients, such as calcium, magnesium, potassium, iron, manganese, zinc etc, and also has a high waterholding capacity. Therefore it is called"Tropical chernozem". The entire environment is very poor because of little soil with large quantity of stone in this area, but certain limited is exellent so that lush grasses and shrubs of which most have important economic value can grow on the rock caves and cracks covered with only 5% soil. Meanwhile other precious or valuable tree species which are calcipete, fertile and suitable in site can be planted easily.

This research work carried out for 6 years (1984—1989) with Chinese fir in provenance forest, seed orchards located at Laoshan and Changle in Zhejiang province, and ordinary forest. Based on investigation and determination at fixed locations in these forests, the anatomic basis and dispersal rhythm of male cone pollen, changes in adaptability of female and male cones to wind pollination, as well as sedimentation and spatial distribution of pollens have been studied in this paper. It was suggested from this study as follows: The Chinese fir seed orchard should be set up near water sources, isolation distance more that 1500m. Female and male clones should be used to decrease up to eliminate aucogamy, which in the proportion of 11:4, and male trees are 1.5-2 times taller than female, tree spacing taken as 3×2.5m, 3×3m and 3×4m.

A new method for studying the epidemic dynamics of forest tree disease by means of Fuzzy theory.was mentioned in this paper,Connecting the interrelations between the disease intensity and dynamics of space and time as an integrated research object, the authors studied the epidemic dynamics of grey spot of Populus simonii×nigra. (Cory……) The average disease index(X), the index of the patchiness (M/M) and the percentage of the infected leaves were caused as the characteristic measures of community dynamics. Dividing the epidemic system of the disease into sereral subsystems to make it simpler.At the same time the prediction of the disease has been studied and the short and mid-period model equations were established as following:The short-period one is Y = 2. 9777 + 1. 0730X₁ + 0. 0073X₈ -0. 3843X₄ The mid-period one is Y = 5. 3457 +0.7483X₁ +0.0029X₈+ 1.1523X₄ The above two prediction equations were available through examining the disease indices in practical survey.

By investigating the utilization of machines in log production line of log yard in Yichun forest region, the authores make researches on the production levels of the log production lines and the machine utilization coefficents in every working procedure.Taking the least loss of machine utilization in working procedure as a goal, the authors have studied the 7 kinds of machine combination types and 17 combination plans. The authores have also analized the log production line (Lmi Si-Y) combined with door type crane and conveyer, and have selected the best combination plan.

In this paper, characteristics of wood temperature change and the relation between wood temperature and the moisture content were studied in the processes of higher and lower temperatures kiln drying. Movement of the evaporation front of free water and the changing effects of water condition to the temperature were analysed. According to the results obtained, the drying process could be controled by means of temperature changes, and the principle of applying this method should be further investigated.

Tunnelling bacteria (TB) decay of the untreated and preservative treated hardwood (Betula pendula) and softwood (Pinus silvestris, Picea abies were was examined with TEM. The mechanism of bacterial entrance into the wood cell wall was studied. TB attack on the cell wall begins from the lumen side. The degradation of cell wall is caused by bacteria moving and dividing within the S₁, S₂ layers of the cell wall. The morphology and ultrastructure of TB and their tunnels was observed. The present work shows that the membrances of the bordered pits and simple pits appear having the capability to resist bacterial action, but bordere and the other part of cell wall are not. As TB can attack the wood treated by 0.5% Tanalith NCA, TB has a cabability of detoxic.

The durability of LVL bonds made from Pinus massoniana and Populus euramericana under radio-frequency curing was discussed in this paper. The loss in wet bond shear strength of emulsified PF resin and acid-catalyzed PF resin was compared after BDB28 and A1080 accelerated aging test. The conclusions are as follows: 1)The bond shear strength of Pinus massoniana LVL bonded by emulsified PF declined gradually to a constant value,about 70% of the previous strength. 2) The performance of emulsified PF is much better than that of acid-catalyzed PF when LVL is under accelerated aging test. 3)For Pinus massoniana LVL bonded by emulsified PF and Populus euramericana LVL bonded by acid-catalyzed PF,the loss of bond shear strength of LVL can be measured with BDB28 method instead of A1080 accelerated aging test.

G-bands in prometaphase and metaphase chromosomes of Cunninghamia lanceolata collected from Huitong county in Hunan province, Rongshui county in Guangxi Zhuang Autonomous Region, and Shaowu county in Fujian province, were induced successfully by appling a improved ASG method. The stripes of bands were clear and in a large number,distributed along the whole length of chromosomes. Band stripes in homologous chromosomes were comparatively similar in numbers, distribution, and size. But the character of band patterns were different among non-homologous ones. There were articulate phenomena in distribution of band stripes. Each articulation separated by light stain area was mostly consisted of two band stripes which were adjacent closely. At the phase of karyokinesis, band stripe numbers and distribution in homologous provenances were roughly similar.

Based on the measurements in 14-year-old Pinus tabulaeformis Carr. Stands which located at Heilihe tree farm in Ningcheng county, Inner Mongolia, consisted of 7 plus trees open-pollinated families and 23 origins, the correlations between early and late height growth among different origins, families and individuals were analysed by means of rank correlation, genetic correlation and phenotype correlation. It was shown that early predicting height growth was valid, and there was a significant correlation between seed weight (1000 grains) and height growth of 1 or 2 years old. Nursery stocks.

With the frass samplied from the Masson pine plantation in South China, a preliminary study on the use of frass in the identification of certain forest insects was reported. The materials covered 3 orders 10 families including 11 species of insects that feed on Masson pine and 5 species on other plants. A key based on the morphological characteristics of the frass was constructed. In order to improve the accuracy of identification, some enviromental fators were also considered. Both the practical significance and the limit of the method were discussed.

Gas chromatography (GC) and High-pressure liquid chromatography (HPLC) were used to detect the phytohormones produced by Boletus sp. and Suillus grevillei. Both fungi could produce ethylene and zeitin but had differences in metabolic activities, and B. sp. could secrete zeitin out of hyphal cell but S. grevillei could not do so.In the bioassay of antibiotic activity using 4 ectomycorrhizal fungi, Boletus griseus and Laccaria amethystea demonstrated their ability to produce intracellular antibiotics against Rhizoctonia solani.

Family of Pearson type was selected as the function of diameter distribution in this paper, and the moment of first order 4 about the orgin was used as a link with distribution function. By means of analytical technology of time series, it recommended a series of dynamic models to express and predict future diameter distribution of existing stand. The practical data from the man made Populus even-aged stand were used to examine the effects of these models and the result was satisfactory.

The from reference point is fixed on the position that diameter of the upper stem is equal to 0.5^1/2 times the diameter at breast height. According to this, the following conclusions are derived: the comprehensive form-exponent of the stem above breast height.It has been proved in practice that the average system error is -0.44% and standard error is 5.24% by comparing the volume obtained from form reference point method, namely ,with that from theseetional measurement.

This paper deals with some factors affecting the power of a table band saw machine. Experimental results revealed that:1. Rpm is a primary factor affecting the empty power.2. The magnitude of the stresses of the saw blade is directly proportional to the empty power.3. The relationship between the saw clip slot and the empty power is in a hyperbolical manner.4. Both the height and the width of a sawtooth are directly proportional to the empty power; the front angle of sawtooth and sawteeth pitch under normal using condition has a little influence on empty power.