To find out the effect of the availability of soil moisture on the survival percentage and tree growth in young plantations,a study was carried out in three typical sites on the mid-slopes with different aspects,southerly, westerly and northwesterly, in northern Taihang Mountains.It was found that soil moisture available was ranged -0.3--20 bar,trees grew normally under the status of soil moisture ranged-0.3--3 bar.However,trees would be,slightly or moderately,suffering from water stress as the moisture available reduced to-3--10 bar and-10--20 bar. The results also indicated that the moisture capacity and range of moisture available is the least on the site southwards,on contrast,the largest westwards. The content and availability of soil moisture varied seasonally. Species choice should be considered to use those more resistant to drought for planting programmes, and the soil water conditions could be very much improved by site preparation.

During 1985-1990 a continuous investigation was carried out in the bamboo (Phyllostachys pubescens) forests at the Dagangshan Experimental Centre, CAF, located in Jiangxi Province,to monitor the structural dynamics of stands. The research results showed that the correlations between DBH(D)and the culm length(H), clear length(HL), crown length(L) and total weight (W) could be expressed in power function,D^b = H (H_L,L,W),where the parameter, a, varies with stem stocking (N)^a of bamboo stands. As the stem stocking rises, the stand productivity will go up, thus the age class distribution within the stand will tend to even out. The differentiation of diameter class generally followed weibull distribution in the stands, however, it would become a normal distribution in some stands with higher productivity.

The anatomical characteristics of rattan stems of the genera Calamus,Daemonorops and Plectocomia growing in China are described. According to the characteristics and quality of the stem and the traditional trade of the commercial rattans five groups are classified for commercial rattans of China,viz.Daemonorops group(one species), Plectocomia group (two species), and the genus Calamus can be divided into three groups, small diameterxgroup (seven species), medium diameterl group(four species) and large diameter group(six species). In addition, the structural differentiation at generic level is discussed.

A laboratorv analysis of isozyme phenotype for five natural populations of Pinus massoniana showed that there was an irregular variation in the frequency express of Aap-1^d gene in Aap-1 loci among trees with different levels of growth vigour,in comparison with the standard trees in the sampled plots,the dominant trees had lower average frequencies. Through canonical discriminant analysis,all the sampled individual trees could be distinguished as two groups by frequency express of gene Aap-1d in Aap-1 loci,one group comprised the individuals with Aap-1^d gene, the other with no Aap-1d. The analyses of variance was made for tree height and DBH based on the two groups and the results indicated that significant differences existed in the height growth but DBH. A conclusion could be drawn that height growth of this species was correlated with Aap-1^d genes interlocking other genes which affected negatively the height growth of trees.

Following the quantification theory I,a new non-linear regression model is established as follows:where Y for tree height;t,tree age and x, site factor. In the model parameters could be calculated with the improved Gauss-Newton iteration method. This statistical model could not only be utilized to evaluate site quality but also precisely to predict height growth and site productivity for the different aged stands. The statistica; accuracy could be obviously increased using this model in multiple correlation ratios were 0.9298 and 0.7904, residuals 1.0955 and 1.9636, respectively.

The researches of sex pheromones produced by Celypha pseudolexicola Liu were carried out. The highest percentage of females' calling appears during their 4 h scotophase under a 14:10 light-dark photoperiod, it reaches as high as 85%. The existence of five components in the sex pheromone gland of C. pseudolexicola were confirmed by polar and apolar GC separation. By comparison of extracts from female sex pheromone glands with standard samples and analyzed by Gas Chromatography and Gas Chromatography-Mass Spectrometry, the five components were identified as, 12:OH, Z10-12:OH,12:Ac, Z9-12: Ac, and Z10-12: Ac in the ratio of 6.8:5.4: 24.56: 1:22.29. 15FE extracts, and synthetic components can induce males to start flighting, orienting,and landing at the pheromone sources in wind tunnel,respectively. Field trap studies were also reported in the paper.

The sawfly, Gilpinia massonianais a newly discovered destructive insect to Pinus massoniana Lamb in Chu Xian county Anhui Province. It has two generations per year and overwinter under litter layer as prepupae in cocoons;until next April it emerges into adult. The larvl stage is about 31-54 days,pupal stage 8 -11 days and adult's lift-span about 8-12 days. The eggs are laid individually in pine needle and hatch after 10-13 days, The sex ratio of the adults is 0.52-0. 48. Spetial pattern of larvae is aggregation distribution, and the total amount of pine needle eaten by the larvae is 2. 3g. The sampling method of cocoons is N = B(1.4221x-0.3518), N is total number of cocoons under each tree crown, B is number of cocoons within lm of tree crown from the base of the tree to the periphery of perpendicuar projection of tree crown, xmean size of tree crown. Because the body surface of the 4th instar larvae are covered with a thin large of white wax, it is effective to control 2-3 instar larvae with a smoke generating formulation of diesel oil +2.5% diecise or 20% Shamiejuzhi in mid-May and October.

The paper deals with the translocation,accumulation and attenuation of azodrin inside plane tree following stem brush and their mathematical expression.It is shown that azodrin is used to research on control of pests in plane tree.The following conclusions are drawn:(a)azodrin is transfered in the conductive tissue near the cambium up and down after stem brush;(b)azodrin content in the application site decreases exponentially,and that in the canopy reaches the maximum about two weekes after its application,and then decreases down to zero;(c)more azodrin is contained in the tender branches and leaves than that in the old ones;(d)azodrin has a long life to control pests after stem brush; (e)stem brush of azodrin or its aqueous solution can kill about 95%of slug caterpillar and inhibit the generation of borers in plane tree,and reduce the foliage losses by 60-80%. The conclusion will provide tEe basis for the further study.

Through the formula, N=aD^-b, two mathematical models were established with inventory factors based on 30 plots sampled in the natural stands of Larix qmelinii Rupr.(1),G=aSDI^b(H-1.3)^c and(2),Y=aSDI^bX^c where S for stand; D,density;I,indexl H,tree height and X,the number of stems.These models could be used to generate the standard tables for tree height, dbh, stand density and density control map.

According to the structural features of bamboo, a compressive technique aimed at changing the circular cross section of natural bamboo into a plate form for convenient use is presented in this paper. The new manufacturing method includes three major processes: softening, compression and fixture.The major mechanical properties of compressed bamboo were tested and compared with those of normal bamboo and bamboo mat,the results showed obvious increments in almost all major properties. Some attempts are made in order to extend the application of bamboo by means of composition, fusing compressed bamboo to reinforce aluminum alloy plates.

Developing the utilization of finger-jointed lumber of small size log from thinning by converting the short and crooked wood into long and straight one is of great importance. The effects of the technical parameters,such as wood moisture content, end pressure, press time, curing time after being.jointed, glue spread and finger profile on the bending strength of fingerjointed lumber were studied and the accelerated ageing properties of the fingerjointed lumber with PRF resin were also determined.

Acetylation of wood has been one of the most active research subjects inthe field of wood chemical modification.This article briefly reviews theprinciple, the history and the current situation of wood acetylation. Fourmethods of acetylation and properties of acetylated wood-based products areintroduced. The problem of using this technology is also mentioned.

A new concept,forest-population carrying capacity, is defined in this paper. Based on the concept, a research methodology was developed to analyze the correlations between the forest resources and population, and to estimate the capacity of forest to carry population for the different living standards in the different periods of social-economic development using the data available and economic index, representing the four kinds of basical living materials,which included the average timber consumption per capita, fuelwood, fruits and nuts, and environmental index for necessary forested land per capita. The results showed that fruits and nuts would be over produced, family-used wood in shortage to some extent and the environmental quality would be somewhat improved. However,the supply of fuelwood for the rural community would still remain a serious problem. Changes of the forestpopulation carrying capacity will depend on the consumption structure of forest resources.

This study,by means of the most advanced noise measuring technique and equipment in this world, based on the Comprehensive measurements and analyses on the environmental noise in thirteen Sawmills located in Jilin and HeilongJiang provinces, reveals the status of environmental noise in Sawmills of our Country,puts forward the bases and methods for appraising the environmental noise and provides some scientific bases for tackling the sawmill noise in a comprehensive way.