The biomass,soil characteristics and root distribution of 26-year-old pure poplar(Populus simonii)stand and poplar-seabuckthorn(Hippophae rhamnoides)mixed stand were measured in Ansai,Shaanxi,Loess Plateau.The results showed that mean height,DBH and stand biomass were 44.8%,32.7% and 139.76% higher in the mixed stand than in the pure stand respectively.Biomass allocation patterns of two forest stands were different remarkably.Total biomass,as well as each of the parts in the mixed stand,was higher than that in the pure stand.Compared with the pure stand,soil bulk density and porosity of each layers in the mixed stand were respectively reduced and increased;soil water content in the mixed stand is higher except in August;and the soil total N content and rapidly P were 5%～69.0% and 22.4%～233.3% higher in the mixed stand,with total P content almost unchanged.Poplars root system in the pure stand(diameter<3.5mm and 3.5～10mm)were mainly distributed over soil 0～30cm,yet those in the mixed stand were distributed deeper and evener.On the contrary,the distribution of the poplar root system(diameter>10mm)in the pure stand was deeper and evener than in the mixed one.Horizontal distribution extent of the poplar root(diameter<3.5mm and 3.5～10mm) in the mixed stand was close to this in the pure one,yet the other one(diameter>10mm)in the former was narrower than the latter.

Forest ecological benefits were indirect useful value.Forest ecological benefits effective area coefficients were put forward to evaluate generalized forest ecological benefits.Forest ecological benefits physics and monetary quantum model were entirely different.The physics quantum is a kind of general linear model——apparently non-correlative model.Considering of the externality of market failure,the Green Pareto Optimum was pointed out.Replaced market method should be adopted to evaluate forest ecological benefits monetary quantum,which was necessary condition to realize scientific evaluate forest ecological benefits.To scientifically and internalized estimate forest ecological benefits monetary quantum,the approaching market theory was built.According to the similarity and replaceable of forest ecological benefits with its replaced merchandise,basic principle of the approaching market coefficient and mathematics model were built by means of digital approaching.They were characteristic of future environmental market.Two kinds of monetary construct model built the foundation of internalize forests ecological benefits.

According to the latest national investigation in 1999, the area of desertification in China is 267.4×10 4km 2, accounting for 27.3%of the whole territory. In China, the interlock area of farming and pasturing in Semi-arid region is the main region which is affected by desertification seriously. In this paper, in order to analysis the intensity of natural and human activity in desertification process, the Yijinhuoluo County which was located in the interlock area of farming and pasturing was selected as a case study area. On the basis of abundant data from 1959 to 1999, the population quantity, population density, population natural growth rate, agriculture and non-husbandry population, non-agriculture and non-husbandry population, livestock quantity, cultivated land, irrigated land, grain planting land, forest land, afforestation land, total production value of agriculture and husbandry, annual precipitation, annual mean temperature, annual relative humidity, the day of gale, the days of velocity above 5m·s^-1, the days of sandstorm and annual mean wind speed were choosen and the principal component analysis method was used to measure the intensity of nature and human activity factors quantificationally. The results showed that in the process of the desertification process, 53.8% was caused by anthropogenic activity, 10.0% was caused by nature factors, and 23.4% was caused by anthropogenic activity combined with nature factors in Yijinhuoluo County. In the study area, the main anthropogenic factors included population(number, increasing rate), forest land and planting land area, the nature factors were annual preicipitation, annual mean temperature, the day of gale and the days of velocity above 5m·s^-1. Comparing the anthropogenic factors and land sandy desertification, it was found that the anthropogenic factors had two effects in the process of desertification, in which it can accelerate the desertification process in some times, but in another period it can restrain the desertification process. By reducing the population natural growth rate, enlarging the area of irrigated land and forestry land, and increasing the meliorated and artificial grassland, the desertification can be controlled easily.

In order to find out the rule of turbulence and to quantificationally analyze the vertical transport of energy and material over forest, the sensible heat flux and latent heat flux over broadleafed Korean Pine forest on Changbai Mountain are calculated, using the data measured by the Routine Meteorological Measurement System and Open-Path Eddy Covariance Measurement System, based on the eddy covariance and aerodynamic methods. Then the results mentioned above are compared.The results measured by these methods are very close in quantity and the change with time, and their linear correlations are significant.

Tetraena mongolica belonging to Zygophyllaceae is the ancient relic plant of Tethys seatropical floristic region. It only distributes from Bayan Gele, west of Inner Mongolia Autonomous Region to Shizui Mountain, east of Ninxia Hui Autonomous Region. T. mongolica, which plays the important role in the windbreak sand-fixation and soil and water conservation, is on the verge of endanger in recent years, so it is listed as the second-class national key plant for protection. In order to probe the mechanism of endanger of T. mongolica, this paper dealt with the initial fruiting age, the distribution, quantity, and weight of fruits, transformation rate from flowering to fruiting, and the relationship between fruiting rate and age of T. mongolica, and analyzed the cause of low fruiting rate. Total 70 plots with the size of 10m×10m each were set up in two sample strips with the size of 10m×3 800m each, and the community composition, base diameter, crown width, and the number of the individual trees of T. mongolica, soil moisture and pH of plots were investigated. The age of the trees was identified by the ring method. 5 individual trees of each age class at intervals of 3a were sampled, and the transformation rate from flower to seed and seed bearing rate were surveyed. The method of nylon net with hole size 1mm×1mm was used in 8 sample trees to calculate seed bearing rate and to analyze the cause of low rate of seed bearing. The results showed: 4 years old T. mongolica was in the initial fruiting age, the spatial sequence of fruiting distribution in the individual tree was upper, middle, and lower part of the crown,and seed production with the change of individual age was in the one-peak type curve. With the age increase of individual, the number of fruit bearing increased from 4 to 18 years old, and declined after 18 years old. 15～27 years old was peak period for fruit bearing. The change of fruit weight with age showed the similar curve to the former, and the rate of seed bearing varied from 1.26% to 2.80%. The change of seed bearing rate showed 2-peak type curve over age.

In vitro rhizogenesis of Juglans regia cotyledons from mature or near mature fruit was investigated. The top, middle and basal sections of the cotyledon showed different rooting capacity. On 1/4 DKW basal medium supplemented no plant growth regulators, the rooting ratio of the top section was 100%, while the middle and basal had no rhizogeneesis. The endogenous indoleacetic acid (IAA) level in the rooting top sections presented as increasing at the culture beginning, then maintaining at a level during the differentiation of root primordia, and increasing again to form a peak when the primordia started to grow (4 days after culture). However, the IAA in the middle and basal sections without rhizogenesis showed decreasing dramatically at the culture beginning, then maintaining at a certain level. SDS-PAGE demonstrated that 62.8 and 38.4 kDa were the rooting related protein bands in walnut cotyledon. Former up_expressed and later down-expressed in the rhizogenesis. Application of exogenous indolebutyric acid (IBA)(0.5～10 mg·L^-1)in the medium had effects to induce the middle and basal sections to root and to regulate their endogenous IAA changes similar to that happened in the rooting of the top section. Meanwhile it up-regulated the expression of the 62.8 kDa proteins and down-regulated 38.4 kDa protein bands. Exogenous 6-benzylaminopurine (BAP) inhibited the rooting of cotyledon top section and restrained the rooting-related changes on IAA and proteins. The system that IBA induced J.regia cotyledon rooting by regulating rooting-related IAA and proteins could be taken as a good research model for the further investigations on molecular rhizogenesis mechanism of woody plants.

The characteristics of seed dormancy and germination of Pinus bungeana were studied with naked embryos (seed capsule and endosperm were excised off) and embryos with whole or partial endosperm of the seeds either non-pretreated or low temperature stratified. Naked embryos were cultured separately on agar-solidified media containing different concentrations of sucrose or on filter-paper bridge. Embryos with whole or partial endosperm were cultured on filter-paper bridge. For naked embryos of the seeds without pretreatment, radicles could emerge on culture system of neither filter-paper bridge nor agar media supplemented with low concentrations of sucrose; 20% of the radicles could germinated on media containing 3.0% of sucrose, the germination rate tended to rise when sucrose concentration in range of 3%～5.5%, the highest germination proportion (Gp) could reach 40% and the germination index (Gi) were 6.5%·d^-1. The remainder 60% of embryos could not germinate even when sucrose concentration of the media was higher than 6%. For the non-pretreatment seeds cultured on filter-paper bridge, 92% or 74.7% Gp was obtained as embryos with whole or two-third to half of endosperm. No growth of radicle except hypocotyl elongation was found of embryos with 1/3 part of endosperm, and naked embryos still in dormancy except the rapid hypocotyl elongation, which could culture on either one matrix experimented. For embryos pretreated by cold stratification for 36 days or GA₃ immersion, naked embryos could germinate on agar media containing lower concentrations of sucrose (0.2% or 0.4% respectively),and 90% of Gp was obtained on media supplemented with 3.0% of sucrose after stratification, 60% of Gp was got on media with 4.0%～5.0% sugar after GA₃ treatment, and Gi was 26.3%·d^-1 or 7.5%·d^-1 respectively. 70% of naked embryos germinated at the third day, but embryos with intact endosperm germinated at 40%, 10%, 10%, 10%, 0% and 30% separately from the fourth to ninth day. From these results we inferred that the embryo was of property of dormancy, but its hypocotyls were not. The testa permeability was not the main factor to inhibit embryo germination, embryo germination did need enough sucrose supply and was regulated by its endosperm.

The application of theoretical growth equations to the field of stand diameter structure has important significance in both theory and practice.In order to look for the inside and outside mechanism,and be elective and distinguished to use theoretical growth equations,this paper,in the view of stands and equations,studies and discusses this problems.The results showed:that there was not obvious influence of age,site index,density and thinning weight on modelling precision of six growth equations,such as Richards,Logistic and Korf so on,but there was a distinctly difference in modelling precision significant among equations.The inflection points of curve of stands cumulative diameter distribution mainly ranged,from 0.4 to 0.6. There was a close correlation between the value distribution of inflection points of growth equations and the modelling precision of equations,the wider the effective inflection point range of the best fit curve of equations was,or the higher the precision of inflection points was.The bigger the validity of inflection points was, then the modelling precision of equations would be higher.

A provenance-by-phosphorus-interaction trial of Pinus massoniana at age 5 was conducted to study genetic response of different provenances to phosphorus supply and their nutrient characteristics of rhizosphere soil under phosphorus stress.Significant phosphorus effect was found for both provenances of Cenxi GX and Gaozhou GD regarded as sensitive provenances to phosphorus supply,while Xinyi GD provenance and Wuping FJ provenance had higher tolerability to phosphorus stress or less sensitivity to phosphorus supply.For Chongyi JX provenance,the response to phosphorus was found to be marked only at age 2 or 3.There existed great differences in chemical characteristics of rhizosphere soil among 5 provenances. Percentages of organic matter,total N,hydrolytic N,and available P in rhizosphere soil were usually much higher than those in non-rhizosphere soil.Result indicated that P.massoniana roots of different provenances had an effect of soil phosphorus activation and available phosphorus enrichment,especially both provenances of Xinyi GD and Wuping FJ,which could preliminarily explain their genetic mechanism of adaptation to phosphorus stress.Marked acidification was not observed in their rhizosphere soil for provenances tested.

Pinus tabulaeformis forest mixed with deciduous oak species such as Quercus mongolica and Q.liaotungensis is the zonal native vegetation in Western Liaoning Province. However, the present artificial vegetation dominated in Western Liaoning Province is monocultures of P.tabulaeformis. It is of great significance to introduce oak species into the pure P.tabulaeformis plantations to promote the restoration of P.tabulaeformis forest mixed with oak species and the sustainable management of the pure P.tabulaeformis plantations. The objective of this study was to investigate the afforestation techniques for Q.mongolica, Q.liaotungensis and Q.acutissima under the semiarid conditions in Western Liaoning Province. In view of the natural conditions in Western Liaoning Province, a series of direct seeding and planting experiments for oak species under different shading conditions such as in the cutting strip of P.tabulaeformis stand, under the canopy of P.tabulaeformis stand and in the open stand of P.tabulaeformis were carried out. The results showed that oak growth was characterized by growth of root system during the first 3～4 years after seeding or planting. However, it was dominated by the elongation of the taproot while the absorptive root was too less to maintain balance of water contents between the above and below ground parts of the oak seedlings and saplings. This was the main reason for the failure of oak afforestation in wild land in Western Liaoning Province. Under shading conditions, transpiration rate of oak seedlings decreased greatly because of the drastic reduction of light intensity, which reduced the waste of water in summer, while in winter and at the end of winter and at the beginning of spring, seedling death rate resulted from top_drying or withered stem after physiological drought was greatly reduced. Both situations contributed to the high survival rate and satisfactory growth of oak seedlings and saplings. The survival rate could be as high as 100% in the first few years when afforestation was done under closed canopy of P.tabulaeformis stand, but the growth increment of height and diameter was less. This phenomenon became more obvious with increase of age of the seedlings. The survival rate of oak saplings at the age of 6 years was more than 90%; the average basal diameter of trees ranged from 0.45 to 0.95 cm; the average tree height from 19.5 to 32.3 cm; the root system reached a depth of 70.5 cm, the width in diameter was 1.728 cm, and the width in diameter where the root was broken was 0.344 cm. With the increase in number of lateral and fibrous roots and the enhancement of their adsorptive capability, the oak saplings was at a stage of stable growth from 6～7 years onwards. Based on this study, it was concluded that the following set of techniques should be followed to guarantee the success of artificial oak afforestation in Western Liaoning Province:(1)Afforestation under shelter such as in the cutting strip of P.tabulaeformis stand, under the canopy of P.tabulaeformis stand and in the open stand of P.tabulaeformis, but afforestation under closed canopy of P.tabulaeformis stand should be avoided; (2) Direct seeding in autumn with careful site preparation, seed screening and classification before seeding, and a favorable mulching soil layer depth of 5～8 cm, but places where were heavily damaged by mouse or hare should be avoided; (3)Selection of site with a thick soil layer depth; and (4) Careful tending, particularly stumping of saplings.

According to the probability and mathematical statistics theory,19 quantitative characters and their distributions of 124 Chinese jujube(Ziziphus jujuba Mill.)varieties were studied.The results showed that acid can be titrated in fresh fruit,growth period,soluble sugar of dry fruit,length of second branch,internode length of growing branch,length of bearing branchlet,flower number of bearing branchlet,weight of fruit kern conformed to the normal distribution;but those of per fruit weight,Vc of fresh fruit,soluble sugar of fresh fruit,edible percent of fruit,acid can be titrated in dry fruit,fruit number per bearing branchlet,internode number of secondary branch conformed to χ² distribution.The values of normally distributed characters could be divided,in a unified way,into 5 grades by 4 dividing points:(X-1.281 8S),(X-0.524 6S),(X+0.524 6S) and (X+1.281 8S),or into 3 grades by (X-0.524 6S) and (X+0.524 6S).In the former case,the occurence probability of 1～5 grade was 10%,20%,40%,20% and 10% respectively.Through comparison,characters conforming χ² distribution may be simply treated as those conforming normal distribution for convenience.Index system of probability grading for 19 quantitative characters was built.

The technique that digging holes and covering film in big fish-scale pits and drip irrigation under film can solve the problems about the low survival percentage, the slow growth and the late development of the cash trees on the arid slope-land planted on the hilly and gully area of loess planteau. The results showed that the apricot's percentage of survival increased to 96%, and the jujube's percentage of survival increased to 92%. The fish-scale pit collected runoff so as to increase the utilization ratio of rainfall, about to 42.5%, moreover, drip irrigation under film with saving water bag refrain the soil from compactness, and decreased the evaporation of soil, which increased the yield of apricot and jujube respectively 10.32% and 19.61% comparing with control.

A new species in the genus Aprostocetus is described in present paper:Aprostocetus magniventer Yang (Hymenopetra, Eulophidae:Tetrastichinae). It is an endo-parasitoid in the pupa of Fall Webworm, Hyphantria cunea (Drury) (Lepidoptera:Arctiidae), a serious invasive defoliator species to China. From one host, 45～62 adult wasps were reared out with proportion of female and male 2.6∶1, and parasitic ratio 3.5%. The species has good promising as a biological control agent for suppression of the pest. This unique species is quite different from all other species in the genus Aprostocetus by its great and sub-rounded gaster which is 1.5 times as wide as thorax. The type specimens of the new species are deposited in the Insect Museum of Chinese Academy of Forestry.

It has been showed that females of the pine caterpillar moth, Dendrolimus punctatus mainly use olfactory cues to locate the needle of Pinus massoniana as their oviposition site in an previous study. Oviposition behaviour in this species were further studied by oviposition choice experiments. The removal of pentane extracts from needles of P. massoniana resulted in a significant reduction of oviposition preference to extracted needles than normal ones. Considering our previous study, that pentane extracts of the needles contained volatiles eliciting female electroantennogram respones, present data implied that the volatiles were necessary for female to locate their oviposition site. Comparing with oviposition preferences to pentene-dipping needles, females did not significantly change the preference to the needles dipped with α-pinene, myrcene, limonene, camphor or linalool-pentane solution, respectively. However, females laid significantly less eggs on the needles dipped in 10% β-pinene -pentane solution than those dipped in pentane only. This fact suggested that the needles containing higher amounts of β-pinene could reduce female oviposition perference.

As one type of natural fires, lightning fire was very complex and difficult to control. Lightning fire connected with lights very closely. When lightning happened, especially dry-lightning, which brought little precipitation, surface temperature growing and fuel drying, these led to fires easily. The more forest fires occurred, the more lightning fires did. Lightning fires had Characters of geography, time and topography. Since lightning is random, it was very difficult to prevent and put out forest fire. It was necessary to improve methods of lightning fires forecasting, monitoring and extinguishing.

The upper of Yangtze river was ever one of the most abundant biodiversity area in China. The Three Gorges project, now under construction, would cause some effects on terrestrial Vertebrate. For the Three Gorges Reservoir Area, there were 523 terrestrial vertebrate species, of which 64 species are national protection species, belonging to 19 families, 10 orders; and 47 species are endemic species of China, belonging to 18 families,9 orders, as well as 8 species of those are both national protection and endemic species of China. Based on the characteristics of terrestrial vertebrate, that was complex zoological region and composition diversity,ingredient peculiar and uneven, this paper reviewed the species endangering cause and status of conservation on rare and threatened terrestrial vertebrate, some proposal for conserving the rare and threatened terrestrial vertebrate were presented.

Pheasants were fed the same diet supplemented with 0.5% cellulose enzyme+0.5% starch enzyme, 0.5% cellulose enzyme+0.5% neutral protein enzyme, 0.3% cellulose enzyme+0.3% starch enzyme+0.4% neutral protein enzyme respectively. Results showed that the number of laying eggs, total egg weights and the rate of laying eggs were obviously increased, the rates of fertility and hatchability of hatching eggs were also increased; in the meantime, the ratio of feed to egg and the number of pecked eggs and broken eggs were obviously decreased. The average weight and quality of eggs did not vary significantly (P>0.05),the crude protein and nitrogen-free extraction contents in eggs were increased. In general, the results of adding 0.5% cellulose enzyme+0.5% neutral protein enzyme were best.

A comprehensive determination and deep analysis on the variation mode of fiber and vessel morphological parameters along tree (Populus×canadensis cv. “I-214") height, including length and width, fiber wall thickness, tissue ratio, fiber wall ratio, basic density, width of growth rings, and on the relationship among them were conducted. The present results indicated an initially rapid and then gentle increase of fiber length and width, fiber wall thickness, vessel length and tangential diameter and vessel ratio from pith to outward, while vessel numbers, tissue ratio of fibers and rays, fiber wall ratios gradually decreased and then tended to stable. The variation of all the anatomical parameters but cell wall ratio showed no significance along tree height. The radial variation mode of basic density was characterized with initially slight decrease followed immediately by a rapid and then much more gentle increase from pith to outward. The delimitation age between juvenile and mature wood was 10～12 years. Compared with mature wood, juvenile wood owned lower basic density, shorter and narrower fibers and vessels, thinner cell wall, higher fiber and ray ratio, more vessels, lower vessel ratio and narrower width of growth rings, and there was significant difference in basic density, fiber and vessel length and tangential diameter, tissue ratio of vessels and rays between juvenile and mature wood. Growth rate imposed no significant impact on anatomical properties, but showed significant negative correlation with the basic density of wood, which was in turn closely related to anatomical parameters. There existed highly significant correlation between the age of growth rings and basic density as well as all the anatomical parameters, so the predictive models could be established.

According to the investigation data in parts of Daxing'an Mountain, Xiaoxing'an Mountain and Changbaishan forest areas, the impacts of cutting intensity on volume increment and regeneration effects were analyzed. Meanwhile, the relations between different cutting intensities and annual mean increment of stand storage and the annual average number of regeneration individuals in different forests were presented by using statistic principles. Results showed that the relation equations was parabola equation between cutting intensities and annual average increment and annual average number of regeneration individuals of stands.

Chitosan,an natural and renewable polymer without toxic and pollution to human beings and environment and the deacetylated derivative of chitin that mainly contain in the crusts of crabs and shrimps, has many good characteristics and used into many fields such as agriculture, medicine, chemistry, etc.. In order to study the mechanism of modification of wood dyeing as dyestuff carrier for fixation, the main wood constituent of Populus tomentosa sapwood pretreated with chitosan and then dyed by acid orange Ⅱ. Degree of dyeing(DD) of main wood constituent and type of chemical linkage between wood and chitosan were determined. The results showed that the degree of dyeing of wood meal, wood meal extracted by benzene-ethanol solution, holecellulose, cellulose, hemicellulose and lignin of P. tomentosa which were dyed by acid dyestuff were significantly increased after pretreated with chitosan. And amino of chitosan bonded with wood components formed ionic bond with sulfonic group under acid condition, which produced sulphonate. So chitosan fixes the dyestuff and improve the dyeing effects as a kind of dyestuff carrier for wood dyeing.

In wood industry engineering systems, the observation vector is often not available in its entirety to the controller, but a quantized version of it transmitted over a communication channel with accompanying transmission delays and distortion, subject to bit rate constraints. This problem has attracted some attention and progress is little in recent years. Feedback control problems for a linear continuous-time system with communication constraints are considered in this paper. The concept of set-controllability is introduced and testified for such a system. Moreover, sufficient and necessary conditions are provided for the systems' controllability, then the system can be reaching.

The impregnation and distribution of phenol resin in Chinese Fir and its improvement methods by extracted and vacuum treated were studied. ERL(effectiveness of resin loading)of phenol resin aqueous solution was 10% under soaking condition at atmosphere, but it increased to 90% under the vacuum condition whether or not the specimens were extracted. The weight of impregnated resin in the wood with vacuum treatment was remarkably higher than that at atmosphere soaking. The distribution of resin at longitudinal direction of the wood was analyzed by soft X-ray densitometry. The results showed that the resin was mainly distributed on the end of the specimens that were treated at atmosphere soaking whether or not the specimens were extracted. The resin by vacuum impregnation can be impregnated more deeply than by atmosphere soaking for the specimens without extracting, and even reach the center of the specimens if the specimens were extracted. The variation of the resin distribution in the wood was small by test for homogeneity of variance and welch test after the specimens were extracted. It means that the impregnation and distribution of resin in the wood were improved by the vacuum and extraction treatment. Meanwhile, in the longitudinal direction and radial direction of the specimens, the resin distribution were analyzed by the microscope to observe the resin loading condition in lumen. In the longitudinal direction, the loading rate decreased from end to the center of the specimens. But the loading rates of extracted specimens were higher than that of un-extracted specimens at the same location in the longitudinal direction.

The paper presented a new testing method and a special testing device for measuring cutting-rate of saw-chains. The cutting-rates of German STIHL saw-chain, American OREGON saw-chain and domestic JL10 saw-chain were measured through operating the device. The force in the vertical forward movement orientation was kept equal when a chain saw was operated in the device. It kept a good coherency between the cutting area determining and the cutting time measuring. So it can improve the measuring precision of cutting-rate of saw-chains. The special testing device was noted for compact structure and small friction resistance to vertical forward movement with a high measuring precision, a good repetitiveness and a wide applicable range. So a good contrast could be obtained in measuring the cutting-rate of saw-chains through the special testing device.

The processes of the lignin subunits biosynthesis pathway especially on the composition of lignin, the reaction steps, the enzymes involved in the lignin subunits biosynthesis pathway, and the rewriting of lignin roadmap were reviewed in this paper. The current researches in China were also discussed. In order to meet the different needs for industry wood and forage, some suggestions were proposed that the lignin biosynthesis research in China should be focused on the improvement of wood quality and forage digestibility, and the changes on total lignin content or subunits composition through the express regulation on the key lignin biosynthesis enzymes.

This paper reviewed the status of complex and interspecies diversity of Bark Beetles chemical communication, discussed the behavior regulation mechanism of kairomones, allomones and pheromones in the host selection, attack, colonization and reproduction of Bark Beetles. And it stated that the semiochemicals biogenesis and release of Bark Beetles effect on the population density, spatial niche and attacking time, and effect on the entomophagous insect species, population density and their control role to Bark Beetles.

According to the principle of bio-diversity conservation,the change pattern of the species diversity in gaps of different sizes and developmental stages in Castanopsis kawakamii forest was measured and analyzed by means of Margalef index,Shannon-Wiener index,Pielou index,Simpson index and Evenness dominance diversity index.The results showed that the general trends of species richness index were correspondent with those of species diversity index,evenness dominance diversity index and species evenness index,which were in opposite to those of ecological dominance index.The species diversity influence in shrub layer by gaps of different sizes and developmental stages was the strongest, the one in arbor layer was stronger,and the one in herb layer was the weakest.The species diversity index (Shannon-Wiener index) in ardor layer reached the highest in the gaps with a size of 80～160m²,and occurred a higher peak in those with a size of 240～320m² again,and became lower in the gaps of above 400m².Diversity index in shrub layer reached the lowest in the gaps with a size of 80m²,the highest in those with a size of >200m²,and occurred a higher peak in those with a size of 80～160m².Diversity index in herb layer reached the lowest in the gaps with a size of 80～160m²,the highest in those with a size of >400m².Diversity index in arbor layer showed the high change trend in the middle period and the low one in two periods following the ages of gaps,which the index were the highest in the gaps about 40～50 years,and the lowest in the first 10 years after gap formation.The change trend of diversity index in shrub layer was the most evident,which formed a peak value in the gap ages of about 10～20 years and reached the lowest in 40～50 years of gap formation.The change trend of diversity index in herb layer increased following the ages of gaps formation,and diversity index in herb layer reached the highest after 50 years of gap formation and the lowest in the first 10 years after gap formation.Gap formation can increase species diversity and is one of the most important mechanisms for the maintenance of species diversity in C. kawakamii forest.The study will provide a reference for the protection of biodiversity and the natural regeneration in C. kawakamii forest.