This article emphatically reviews the difference of soil biological activities, biochemical activities and soil chemical propeties between the rhizosphere and non-rhizosphere soil of first rotation of Chinese fir(Cunninghamia lanceolata(Lamb)Hook)plantation.It also reviews their dynamic patterns during Chinese fir plantation development.The results show that the contents of organic and inorganic nutrients in the rhizosphere soil of young, halfmature and near-mature Chinese fir of first-rotation are more than those in non-rhizosphere soil, except for total K in young Chinese fir plantation.Various patterns of soil nutrients in different stages of Chinese fir plantation development are as follows:Available N shows the trend of declination in both rhizosphere soil and non-rhizosphere soil; the content of available P also declines, only increases a little from half-mature stage to near-mature stage, but total P decreases from beginning to end.The content of available K increases from young stage to half-mature stage, but decline from half-mature stage to near-mature stage both available K and total K.The contents of Cu, Zn, Mn, decrease greatly from young stage to half-mature stage, and rehabilitate a little from half-mature stage to near-mature stage in non-rhizosphere soil.As for the variation of the soil enzyme activity, both hydrolytic enzyme and oxidizing enzyme are less active in rhizosphere soil than in non-rhizosphere soil at young stage.However, when Chinese fir become into mature, the activities of soil enzymes are higher in rhizosphere soil than those in non-rhizosphere soil.The results of soil micro-flora show that the quantity of bacteria, actinomyces, fungi in rhizosphere soil is more than that in nonrhizosphere soil in the young Chinese fir plantation.The quantity of bacteria and fungi decreases in rhizosphere and nonrhizosphere soil, but the quantity of actinomyces increases along with the Chinese fir becoming into half-mature. From half-mature Chinese fir plantation to near-mature stage, the quantities of bacteria, actinomycetes and fungi increases.The variation of the three types of microorganism in genus, species and amount in rhizosphere soil and nonrhizosphere soil during stages of Chinese fir plantation development indicates the dynamic process of soil degradation.The clear scientific evidences are provided for revealing mechanism of soil degradation of Chinese fir plantation and finding technigue way of prevention and cure by researching soil properties of rhizosphere and non-rhizosphere.

Experiments involved optimal N, P, K and B ratio of fertilization in young trees of Eucalyptus urophylla were carried out by"416-A"optimum-mixed design.A polynonial regression equation was established which expresses the mean tree height as function, and the applied amount of N, P, K and B as variables respectively.Using the regression equation, two optimum fertilizer recipes can be obtained by computer processing.The first fertilizer recipe is N₈₀P₄₀K₄₀B_2.5(kg/hm²), and the target tree height is 4.53m.The second fertilizer recipe is N_34.9P_17.45K_17.45B_1.1 (kg/hm²), and the target tree height is 2.45m.Being fertilizing too much or too small N, P, K and B fertilizers, it will cause the bad growth.The order of N, P, K fertilizers which are needed by young trees of E.urophylla is K>P>N.Fertilizing reasonably can extend the fast growing period of tree height.The nutrition status of young trees of E.urophylla was diagnosed by using diagnosis of critical value.

Based on the sampling analysis, concentration and variation of five elements which are N, P, K, Ca and Mg in different organs for three growth stages of Castanea henryi plantation have been studied.The results show retention of each elements gradually become higher from the first stage to the third stage.The accumulation for N and Ca made up large percentage, then was K, Mg, the least was P.During the first growth stage, the return were 1.763 kg·hm ^-2a^-1for N, 1.695 kg·hm^-2a^-1for Ca, 1.252 kg·hm^-2a^-1 for K, 0.632 kg·hm^-2a^-1 for Mg and 0.156 kg· hm^-2a^-1 for P respectively.The second stage, the return increased by 6.6901 kg·hm^-2a^-1 for Ca, 6.0027 kg·hm^-2a^-1 for N, 3.6796 kg·hm^-2a^-1 for K, 2.0822 kg·hm^-2a^-1 for Mg and 0.5945 kg·hm^-2a^-1 for P respectively.But in the third stage, K become the most element of return and the least of return was still P.Circulation rate of each element from the first to the third stages increased and turnover periods shortened.The reasons of variation have also been analyzed.

An ecological study was carried out on secondary metabolites(bioactive constituents)in the leaves of Eucommia ulmoides through determining the contents of the metabolites and ecological factors in the leaves collected from different regions.The results were as follows :The contents of metabolites in the leaves collected from different regions showed significant differences.The leaves collected from Zunyi contained the highest contents of geniposide, chlorogenic acid, aucubin, and flavonoids. Geniposidic acid reached the highest content in the leaves from Cili.The leaves from Luoyang showed the lowest content of geniposide.The contents of chlorogenic acid, aucubin, geniposidic acid and flavonoids were the lowest in the leaves from Yichang, but hightest gutta-percha.These showed that ecological factor was also an improtant one in regulating secondary metabolism.Stepwise regression analysis and path analysis indicated that the major factor influencing the synthesis and accumulation of metabolites was the contents of trace elements, meteorological factor however, showed little influence. The relationship between the contents of available trace elements in the soil and in the leaves was not in completely direct correlation.Different results were obtained in stepwise regression analysis and path analyses when the contents of trace elements in the soil and in the leaves were used as the main factors respectively.Through systematic cluster and fuzzy complex discrimination, it was concluded that the contents of secondary metabolites were high in the leaves from Zunyi(Guizhou Province), Cili(Hunan Province), Lueyang(Shaanxi Province), Tongjiang(Sichuan Province).

The basal growth prediction is a kernel factor and foundation in the model system of stand growth and yield prediction.Richards Growth Model including stand density index, age and site quality index was taken as basal area growth model.The functional relationship was developed between Crown Competition Factor (CCF)proposed by Krajicek et al.and stand density index by Reineke and number of trees per hectare by using the characteristic of CCF reflecting tree competition in stand to certain degree.Acco rding to the function, the conclusions for L.olgensis and C.lanceolata are as follows; 1)CCF < 200, showing stand growth with constant tree number; 2)200 ≤CCF ≤300, transition of growth from constant tree number to the self-thinning, in other words, the change of SDI(stand density index)can be described as linear combination of the growth with constant tree number and the self-thinning; (3)CCF > 300, stand growth in the self-thinning.

Dynamics of evergreen broad-leaved forests dominated by Cyclobalanopsis glauca in Zhejiang, China was studied.Species composition of the forests indicated that it was dominated by evergreen species with fairly proportion of deciduous species in all four stages.LAI of the forest tree layers was bigger in 7 years forest than that of 20 years forest, and it increased gradually after 20 years.Diversity of the individuals and amount of species of trees, subtrees, liana and herbs were highest in 7 years.Shannon - Wiener index of tree, subtree, and herb layer in four stages was respectively 3.32 ~ 4.88、3.59 ~ 4.14、1.14 ~ 2.36, and its dynamic characteristics was similar to that of the community structure and species numbers.C.glauca can germinate fast in the cutover land, it is dominant in the 7 years young forest.Because of this, the community demonstrates condensed succession to go to the phase of evergreen broad-leaved forest quickly.C.glauca population was short of seedlings and saplings and its size class structure shows as spindle shape in 40 years, the reasons for this were:the population age was young, the seed pool was destroyed by animals and microbes, sprouting of seeds and growing of seedlings needed certain conditions such as light, temperature, and humidity' etc..To fill up the vacancy of seedlings and saplings, mother ramets can grow a lot of daughter ramets and sprouted branches.In the later stages, it may be propagated by sexual and/or asexual ways according to the habitat to consolidate its dominant position. Biomass, growth-yield of tree and subtrees layers increased with the development of community.

Having studies 58 trial materials and consulted Thompson' s evaluat ion system of European hazelnut, the author established preliminarily a system of character description and evaluation of Corylus L.germplasm resources in order to distinguish the species feature in northeastern China.Meanw hile, the standard leaf sampling position, the theoritical sample volumes of numerical value character and classifing standard w ere determined.The approaches provided the basis for studing sy stematically Corylus L. germpleasm resources in future.

Chinese fir is the most important fast-growing and high-yield tree species in southern China, it occupies a very significant position in Chinese plantation management. However, the rate of sterile seeds of Chinese fir is high, for example in Fujian Province, which seriously affects the production and development of Chinese fir. So it is an urgent problem to study the prediction and prevention of sterile seeds in the production of Chinese fir seeds. For the sake of revealing the epidemic law of sterile seeds, this paper studied the relationships between Chinese fir sterile seeds and geographic epidemic by a new method-artificial neural network.Artificial neural network is a good method in handling the overall nonlinear mapping problems between input variables and output ones, which has a wide application in many research fields such as system simulating, automation controlling, paralled data processing and so on. In this paper, the authors selected BP artificial neural network to deal with the relationships between Chinese fir sterile seeds and geographic epidemic, where the input variables are longitude and latitude, the output variable is rate of sterile seeds of Chinese fir, the number of neurons of hidelevel (M) is M=2L+1 according to document (L is the number of factors of input-level), and the network activity function is Sigmiod function as follows: F (x) =1/ (1+e^-x). Using the built BP network, the samples were trained until =min, where O_nj and Y_nj are output values of network and real values of rate of Chinese fir sterile seeds respectively, N is the number of trained samples, and E_j is sum of square deviation of BP network. If E_j didn't converge, the weights and thresholds of BP network were adjusted as follows: The results showed that the accuracy of BP model in simulating the epidemic rate of Chinese fir sterile seeds in different countries is high, which is 88.40%. Thereforce, this paper not only provided a basis for establishing Chinese fir seeds orchard rationally, but also opened up a new train of thought in the application of artificial neural network to forestry research.

Symbiotic fungi of Dendroctonus armandi such as Ophiostoma sp.and Leptographium sp.were the precursors to overcome the resistance system of host trees and the main factors to cause the host t rees to die.Symbiotic fungi destroyed the bleeding cells and developed in resin ducts, blocking up resin ducts of host trees.At the same time, following the development of symbiotic fungi in inner xylem of host trees, fungi hyphae solved epithelial cells of host trees, which resulted in the disorder of the nutrient and water metabolic of the host and the quick death of host trees.

An inducer, up to the highest yield at seventh day of ferment incubation of Fusarium solani, was tested for its tolerance to higher temperature.An induced Zanthoxylum bungeanum resistance against footrot was appreciated by 4 methods of induction injection with hot-treat ferment liquid of Fusarium solani.The root injection and root-stock injection methods gave good effect when the challenge inoculation with Fusarium solani was conducted after 5 days of induction.T he induced resistance of the plant expressed at 10 days, reached peak at 20 days and lasted 36 days with root-stock injection method.The plants were induced repeatedly at 10 days and 20 days, respectively, which resulted in increasing induced resistance f rom 38.1 %~ 81 % up to 60 %~ 95 % by 4 times of induction and in lasting expression of induced resistance from 35 days to more than 55 days by 4 times of induction. There w as linear relationships between induced resistant effect and injections ferment liquid quantity in some dosage range.

This study, on one hand, researched into the relation between occurrence of armand pine bark-weevil and envromental factors and on the other hand, it also carried out an exploration to grading of damaged trees, spatial distribution pattern of pupa and smapling technique.The results demonstrate that the trees damaged by the armand pine bark-weevil can be graded into 4 levels :normal, primarily infectious, nearly withered, and withered.All the spatial dist ribution patterns of pupa are aggressive dist ribution, the best sampling position is the foot of tree, and under 99% reliability, the environmental factor which has major influence on the number of armand pine bark-weevil population is growing potential of trees.

Aponychus corpuzae runs bisexual reproduction or arrhenotoky; Female adult oviposits 1~2 eggs every day and the total is 9.8 eggs averagely in life cycle, The sex ratio is 2.35:1 in nature.Female adults and eggs in diapause from November to March the following year.In certain temperature range, the mites growth become quicker with the rising of the temperature, and their grow th accumulated temperature from egg to lying egg is 280.76 d.℃.Besides Phyllostachys heterocycla, the mites can aslo feed on the le aves of Dendrocalamus basihirsuta, Pleioblastus incannatus, Indocalamus longiuritus and Bambusa pachinensis, and complete their life cycle, but can' t feed on D.latiflorus and Phyllostachys nigras.shortterm raining cause the larvae, nymphs and adults to die intensely, 69.35 %mortality are found from the egg soaked in w ater over 24 hours.Analysis result by the gray sequence theory indicates:the g ray sequence of factors to the amount of the larvae, nymphs and adults is humidity >rainfall>natural enemy >air temperature, and of factors to the eggs or the population is all humidity>naturalenemy >rainfall>air temperature.

The results of bioassay and field efficacy tests of the nuclear polyhedrosis virus of Chihuo zao Yang were reported in this paper.Early third-instar larvae were fed on jujube tree leaves immersed with polyhedral inclusion bodies(PIB)suspension of virus.Mortality of larvae increased with the increasing of concentration of polyhedral inclusion bodies suspension.The LC₅₀ and 95% confidence limits were 3.65 × 10⁵ and 4.04 ×10⁴ ~ 3.13 ×10⁶PIBs/mL, respectively.The LT₅₀ values for the virus concentration of 2.5 ×10⁷, 1.25 ×10⁷, 2.5 ×10⁶, 1.25 ×10⁶ and 2.5 ×10⁵ PIBs/mL were 7.49, 7.94, 9.08, 9.57 and 10.01 days, respectively.A study on larval susceptibility to a concentration of 2.5 ×10⁶ PIBs/mL virus suspension indicated that the LT₅₀ values increased with the increasing of instar(from 5.97 days for early second instar larvae to 12.57 days for early fourth instar larvae).Mortality decreased with the increasing of instar (96.7 % for early second instar larvae, 73.3 %for early third instar larvae and 30.0% for early fourth instar larvae).Mortality of larvae decreased and the LT₅₀ values increased at a low temperature(16 ℃±1 ℃) and at a high temperature(35 ℃±1℃)in contrast to a middle temperature(21 ℃±1 ℃or 26 ℃±1 ℃). The field-release testing were conducted on 8th of May, 1998, when 85% of the larval population consisted of the second and third instar larvae and on 17th of May, 1998, when 85% of the larval population consisted of the third and fourth instar larvae, with virus suspension 2.5 ×10⁶, 5 ×10⁶, 2.5 ×10⁷ and 5 ×10⁷. The adjusted mortility were 90.33%, 90.35 %, 91.80 %, 92.29 % for the first spraying and 66.03 %, 67.31 %, 65.69 %, 69.38 % for the second spraying, respectively, which were analyzed statistically of ANOVA and Duncan' s new multiple-range test.The results from field-release testing indicated that the best time for control Chihuo zao Yang was the first ten-days of May in Taigu, Shanxi and the concentration suitable for control was 2.5 ×10⁷ PIBs/mL, with which the adjusted mortility was higher and the cost was lower.

The radial variation patterns of wood density in 19 Chinese fir provenances were studied by means of Xray wood densitometry.There existed a certain degree of variation in the radial variation patterns of average ring density among provenances and among individual trees within provenances.However the variations were shown mainly among individual trees.After third year, the correlation between juvenile and mature of average ring density reached the significance of 0.001 levels.The analysisy of the correlations between the characters from wood densitometry showed that (1)in the case of the correlations with the variation resulting from the change in ages, the effect of the change in ring width on latewood percentage was significant, and therefore the average ring density was highly significantly correlated to latewood percentage, and the negative correlation between ring width and average ring density also was highly significant; (2)in the case of the correlations with the variation resulting from the change in provenances, the effect mentioned above was less significant, and the average ring density was highly singificantly correlated to the earlywood density, and the negative correlation between ring width and average ring density was much less significant.

The 32 mm furniture manufacturing sy stem is the key to the automation, the current of parts and material in the field of furniture industry.It is very common in the w orld.What CAD is used in developing desig n of 32 mm system furniture is new technology to drive it develop.This thesis probes into the softw are and hardware environment, the development aim, principles and methods of programme design, and the function demand.Resulted show that this kind specialized CAD softw are can raise the w orking efficiency in developing and designing the 32 mm system furniture g reatly, and it can shorten the construction cy cle.

The advances in utilization of entomogenous nematodes for control of forest pest insects are reviewed in this article.Entomogenous nematodes are an important biological control agent in depressing of the population of their host insects.Specially the nematodes of Mermithidae, Neotylenchidae, Steinernematidae and Heterorhabditidae are used on large scale, successfully controlling woodwasps, weevils, carpenter moths.The mass production techniques were introduced from Australia in 1985.It has been promoting the progress in control of insect pests with entomopathogenic nematodes in China.Various insect pests are tested in field trials in Beijing, Tianjin, Fujian, Hubei, Liaoning, Jilin and so on.The tested insects include Carposina niponensis, Atrijuglans hetauhei, Hoplocampa spp., Arbela bailbarana, Zeuzera multistrigata, Holcocerus insularis, Apriona germar, Aromia bungii, Pristiphora beijingensis, scarabs and so on.In the field trials the results indicate that entomopathogenic nematodes are the effective bio-control agents in the cryptic insect pests.

Forest ecosy stem is the biggest land ecosy stem in the w orld.Public w elfare forests in building forest ecosystem are possessed of nonexclusive characteristic of public goods, which leads to economic ex ternality.It is an im portant facto r of market failures and causes law-efficient allocation of ecological resources for a long time.Only if effectively to solve the problems of market failures, can we make the balance between ecology and economy so that we can keep good quality and hig h efficiency in building forest ecosy stem in China.By way of analy zing the market failures, the paper raises several countermeasures such as combining property rights, Coase theorem and g rade price of ecological quality in o rder to amend a part of market failures.The article concerns that the price fluctuation of tim ber exerts an influence on supply of ecology, therefo re w e should timely adjust the grade price of ecology as price fluctuation of timber in order to assure effective supply of ecoloy.

The pattern of economic forest of double-terraced field with slope interval was studied systematically, including the measures of increasing soil moisture, fertilization and fruit yield.The results showed that soil moisture of double-terraced field with slope interval(main terrace) in growing season was 2.1 % higher than that of ternace without slope interval.The yield of dry grass in auxiliary terrace was 1kg/m², which can be used in burying fresh grass into soil of main terrace or covering the surface of the main terrace soil, so as to increase the soil nutrient contents of the main terrace.The kernel yield of 5 -year-old individual apricot tree with sweet kernel increased 69.4 % compared with terrace without slope interval.And there was significant difference in tree growth between terrace with and without slope interval.

Based on the results of more than ten year' s scientific research and practice, some key techniques for cultivating poplar veneer glued wood were summarized systematically.The results were as follows :(1) Selecting appropriate poplar clones for various cultivation zones according to their growth rate and wood quality.(2) Choosing good sites being suitable for poplar clone growing (at least SI ≥18 m).(3) Adopting reasonable planting density which can produce more timbers to meet the need of plywood(the tree spacing should be more than 5 m ×5 m).(4) Using correct planting methods for different soil conditions, however, large seedling with 2-year-old root and 1-year-old stem (seedling height >4 m) were advocated.(5) Taking effective measures to tend the stand, the most effective measure was interplanting with crops.(6) Pruning was neccessary to produce non-node timber, but pruning method, pruning intensity and pruning season should be controlled properly.If the 6 measures mentioned above were carried out, the poplar forests with a high yield and high quality could be ensured.In order to provied some theoretical basis for cultivating poplar veneer glued wood, 4 optimum cultivation patterns were also established using the method of two dimensions system.