From 1982 to 1989, we have studied the surface runoff amount and dynamics of various vegetation types in Guangxi by location comparative method.The results indicated that 1. There are great differences of surface runoffs among vegetative types. The surface runoff of grasshill was greater than that of coniferous forest, which was greater than that of broad-leaved forest or the mixed forest of coniferous forest and broad-leaved forest. The surface runoff coefficients in various vegetation in Guangxi, which have great differences, were Small, averaging 0.78%. The maximum could be 57 times greater than the minimum. 2. Seasonal dynamics of surface runoff was mainly restricted by seasonal distribution of rainfall, and the surface runoff of various vegetations was mainly dependent on the comprehensive effects of crown or plant community, litter layer and soil layer. THe study also showed a pattern of the comprehensive effects that mixed broad-leaved forest or the mixed forest of coniferous forest and broad-leaved forest > grasshill. In this paper, a regression model of surface runoff of yarious vegetation types to precipitation outside of the forest was estabished.

Several basic characteristics of photosynthesis of three oak species in the nursery stock period have been studied by gas exchange method in this paper. The results show 1. For Quercus mongolica, the light compensation point, light saturation point, and light-saturated rate of photosynthesis are relatively high, while its quantum efficiency is relatively low, indicating that it can use solar radiation with high intensity efficiently, but the efficiency of using weak light is low. Such photosynthetic characteristics are opposite in Q. acutissima. Both the light saturation point and light-saturated rate of photosynthesis are relatively hight, at the same time the quantum efficiency is also hight in Q. liaotungensis, but light compenation point is low. Therefore, it can use both high and low light energy efficiently. 2. It is provd that the exponential equation P_n=P_(max)·(1-e^-aI/P_(max)))-R is the most rational for sinmulating photosynthetic response to light intensity in three oak species. 3. The differences of photosynthetic characteristics between Q. acutissima and Q. liaotugensis at various periods of growing season, and the influence of temperature on photosynthetic characteristics in three oak species have been also investigated.

8 sample trees were selected from an 100-year-old beech wood at seriously polluted Exelberg in Vienna Woods. From the entering area of stemflow and the area between stems contrary to slop direction soil samples were taken. Their pH, contents of vegetable absorbent K, Ca, Mg and Mn, total nitrogen and total carbon as well as contents of Pb and Al were measured. In order to study the effect of soil acidification on beech mycorrhizae at 20 different beech sites of the Vienna Woods humus samples were also taken from the area between stems. According to the following characteristics, colour of the hyPhal mantel, branching form and hyPhae, which grow out from the hyPhal mantel into the soil, the sampled mycorrhizae were divided into 17 individual types. Based upon their anatomical characteristics they were placed into one of two groups: 'healthy' or 'damaged' mycorrhizae. The results from the Vienna Woods show that there is not a strong corelationship between the soil mineral nutrients and the beech mycorrhiza. Effects of Pb and Al which is deposited or dissolved through the stemflow on mycorrhiza are very little. The soil pH is favourable for maintaining mycorrhizae in a vigorous condition (Nr. 1) as long as it is above 4.0.

On the basis of the linear relationship between mean crowding m and vatiance(v), a new model to be used for examining insect population spatial pattern and sampling technique is presented by auther in this paper, i·e m-v model (m=φ+ψv). In general, the linear related degtee of m and v is better than m and m. As the (m=φ+ψv) is linear, the estimated values of φand ψ can offer different informatin concerning the spatial pattern of insect population. (1)φ=0, ψ=1, random distribution. (2)φ>0, ψ<1, aggregation distribution. (3)when the m<1 and v>m/(1-m), φ>0, ψ>1, aggregation distribution. uniform distribution. according to the m-v model and the Lloyd's mean crowding formula (m=v/m+m-1), the auther derived a set of new math formula for sampling insect population. they are: (1) the boundary equation of sequential sampling, (2) a formula of determining maximum sampling number, (3) a formula for selecting the opitimum sample unit size of a sample.

The tanget system to be evaluated is a complex system, which is closely related to the forestry socialeconomic system. It is almost impossible to describe and evaluate the behavior and results of this system with a single index. The strength evaluation system, which contains the second class indexes of Input, activity and Output, has been established according to the results obtained and inquiry among nearly 100 specilists who are engaged in the acadmic, educational, productive and adminstrative departments. The third class indexes such as personnel, funds, research projects, outcomes of scientific research, instrument and equipment, information, number of pressed research paper, forestry education, international cooperation and exchange have been analysed in this paper. We conclude from the index analysis that the chinese forestry science and technology possesses fairly good basis in research conditions, but is weak in strength. The paper points out that, if some effective measures are taken to enhance the forest scientific and technological strength, it may undertake the task in some scope to realize the forest economic target of the year 2000 bythe progress of science and technology on certain degree.

In this paper, a new quantitative model of natural selection pressure was derived. Then, 14 natural populations of Populus cathayana and 6 provenances of Pinus sylvestris var mongolica were sampled, and their α, β- esterase isoenzymes were & analysed. In the meantime, by which some data from three experiment published in silvae, genetica were analysed and compared it with other methods. It shows that this theory can solve some problems which cannot been solved by other methods. Besides these, it has other advantages below: 1. very convenient statistical analysis, 2. wide application, 3. easy cooperation with other subjects, 4. great potentialities to be used in many primary biological studies, especially in population genetics.

The workload of forestry production with four typical kinds of work in Great Xinan Mountain Areas of China was investigated by means of the principle of working physiology with a new technique of heart rate measurement. According to the Naticnal Standand GB 935-89, the working strength with four kinds of work, i. e. site preperation in Autumn, manual prepile, transmission light tlinnuing, and afforestation, was graded, The reasonable suggestions concerning arrangement of working time, work quotas,and increase production have been made.

According to the inhibition extent of oxygon released from leaves which are in artificial solution wite a series of low water potentials, the paper proposed a method for measuring the relative drought hardiness of plants. It has been found out that there is a common law for the changes in drought hardiness of evergreen trees in process of hibernation, which is a tendency with "M", i. e. drought hardiness using at the stage of acclimation to cold in the primary period of hibernation, falling drown at severe cold stage, rising again at the stage of air temperature going up, and falling down again at the beginning of spring. With the method incroduced in this paper, the changes in drought hardiness of various tree species or one tree in the process of growth can be compared vertically and horizontally, which provides the bases for the study on environmental physiology and the disposition of various tree species in planlation. Some corresponding water running principles are proposed from the law summarized in this paper.

Transpiration rate (Tr), stomatal resistence (Dr), leaf water patential (Lp) and its corresponding environmental factors of seven tree species have been measured with LI-1600 steady state prometer and pressure chamber. When the soil water potential in 2m depth is-0.04—-0.20MPa, the light intensity is the main factor to influence Tr, which is mainly influened by Dr. The relationship between Li and Dr can be expressed by following formula: Dr=ae^b/Li, thus light intensity according to its influence on Tr can be divided into three regions: Weak light region, Tr=K/Dr, Transition region, Tr=K·ψ_(L-A)/Dr; light saturation region, Tr=a·ψ_(L-A)+b where a, b and K are coefficients, ψ_(L-A) is the difference of leaf-air water potential.

Wind protection effects of forest beer with different widths and ventialtion coefficients have been analvsed bv data obtained from wind tunnel experiments. The results indicate that there is a significant difference between ventilation coefficients. The wind protection effects will decrease with increasing of forest beer width when the line numbers of forest beer are in same. Within the region influenced by wind velocity, distribution of wind velocity in front of forest beer (x>-dH) is in acoord with parabola pattern. And that of wind velocity in back of forest beer (|xI≤22H) is in accord with the systhesis of parabola and logarithm curre.

The rejuvenation character of root-sprouts of Eucommia ulmoides was studied. The result shows that the juvenility of root-sprouts is similar to that of one-year-old seedlings of this tree species. This character could be kept up to the age of two years and then weaken evidently. Therefore it would be suggested that the effective range of ages for collecting soft cuttings of Eucommia ulmiodes should be either 1-year-old root sprouts or 1-year-old trees.

Eighty-eight specimens of poplars infected with Marssonina, collected from nine provinces or autonomous regions in China, were examined. M. populi and M. castagnei were only found in specimens from Xinjiang. M. brunnea were found in the other provinces. The species pathogenic to poplars in Nanjing area should be M. brunnea, other than M. populi as reported previously. Host range tests of three Marssonina species and the relative susceptibility of various poplars to these fungi were conducted with artificial inoculation.

North of Zhejiang Province is a main bamboo-producing district. The bamboo forest is not only in large areas, but also has a concentrated distribution. In recent years, as many bamboo suffer damage by Algedonia coclesalis, Circobotys aurealis, Eumorphobotys obscuralis, Demobotys pervulgalis, Crocidophora evenoralis, Hippota dorsalis, Eutomostethus nigritus, Aiolomophus rhopaliodes, Otidognathus davidis etc. A large part of bamboo stands have withered and become chloratic, some bamboos even died. This cause farmer's enormous economic losses. After testing for many years, it is clear that injecting Tamaron into bamboo carity to control the vatious bamboo insect pests reached a mortality of over 95%. The residue of Tamaron in the bamboo shoots of current year contains some residual Tamaron with the highest amount on the tenth day after injection and gradually decreasing day by day. The residue of Tamaron could not been found in the bamboo shoots coming out next year. Even the highest amount of the residue of Tamaron on the tenth day after injection is only 23.8—47.5%, which is lower than the standard for edible vegetable.

With comparing balance output for profits and losses between hand labour and a loader at the Timber Yard of Weiguo Forestry Bureau, Yunnan Province, their mathematical models for maximum annual output were established, and sloved by a computer. Finally, with comparing production cost between hand lahour and the loader, the critical output completed by the loader is 26610m³, safe operation rate 95.9%. Meanwhile, the critical output for various amount of loaders is also defined.