Dynamics of litter production, nutrient return and decomposition of four Eucalyptus grandis plantations investigated in Hongya County, Sichuan Province. The results indicated:1)The litter production of the E. grandis plantations increased with the increase of the standing density. The monthly variations of litter production were similar in four Eucalyptus grandis plantations, and peak occurred in May and the lowest values occurred in January;2) The ranked order of the nutrient returns was N > K > Ca > Mg > P, The annual macro_element returns of the four eucalyptus forests were 95.32, 86.90, 67.72 and 66.37 kg·hm^-2, respectively;3) The leaf was the main components of the nutrient return, larger nutrient returns occurred in spring and summer;4)The average loss rate of branch and leaf were 18.2% and 36.1% respectively;5)The annual decomposition rate estimated by the exponential decay model were 0.176～0.214 and 0.383～0.445,the half declining were 3～4 years and 1～2 years respectively,95% declining were 14～17 years and 6～8 years respectively. The order of releasing speeds of litter was Mg>Ca>K>N>P,P immobilization was observed, N showed increased in 182 d and thereafter decreased over rest of the trial, K、Ca and Mg loss most in quantity.

Using Geographic Information System(GIS), the change of landscape pattern in Zhangjiajie National Forest Park during 1990—2000 was studied. The result indicated: Landscape pattern is almost no change shown in the indexes of landscape pattern especially division, patch richness and patch richness density. The patch number was increased by 34, increased patch much more is economic forest.

Acacia mangium is a typical and important exotic tree species for short_rotation industrial plantation in south China. It was found that the species could naturally regenerate from seed at appropriate site conditions. The seed of A. mangium in plantations could germinate only in open areas in stand edge. The longest dispersal distance of a single-tree at age of 16 years was 17.5 m and the largest number of regenerated trees was 26 in a 45° sector area around the tree. The distance of single-tree dispersal was not closely related to the number of regenerated trees. The longest distance of dispersal from stand edge of A. mangium was 10.0 m, which were planted with roots buried in hole in 1987, and the largest number of regenerated trees was 3. The longest distance of dispersal from stand edge of A. mangium was 3.0 m for the other stand planted in 1997, and the largest number of regenerated trees was 14. The effects on natural regeneration of native trees, shrubs and herbaceous plants under the A. mangium plantation were surveyed by setting sub-plots within the sample plots. 12 native tree species, 3 shrub species and 8 herbaceous plants species were found. They all have strong viability under the A. mangium canopy. Results indicated that A. mangium can naturally regenerate from seeds and establish itself in open areas in the stands. No significant impact on native tree species and other vegetation was found, indicating that the risk of bioinvasion of A. mangium is low.

By means of sap flow measurement technique with thermal diffusion probe and micro-meteorological station, daily meteorological factors and sap flow of Platycladus orientalis both at different trunk height, in different trunk direction and different diametric singletrees were measured in the Western Mountain of Beijing. Relations between sap flow velocity (SFV) and environmental factors, such as solar radiation intensity, air temperature, air humidity, wind speed and soil temperature, were also analyzed. Result showed that, SFV in upper trunk sapwood was much higher, with an early start_up and a fast ascendant, but descended steeply after got the peak in the late morning and 2 times higher than that in lower trunk sapwood. SFV both in eastern, northern and western orientation in trunk sapwood was similar and much higher than that in southern direction, and there was no certain relation between SFV and its corresponding sapwood width and crown dimension. Singletree sap flow verified according to trunk diameters that large trees sap flow was higher than that of small ones. Daily environmental factors under canopy verified regularly and had a correlation with sap flow significantly. SFV of all the diametric sample trees had a minus correlation with air humidity. And SFV of large trees had a positive relation with solar radiation intensity and air temperature, but small trees were inverse, significantly. Wind speed had an important effect on sap flow conductance. 20～40 cm layer soil temperature had a significant impact on trees water consumption that SFV of large trees was minus related to soil temperature but SFV of small trees was positive. Taking solar radiation intensity, air temperature, air humidity, wind speed, and soil temperature in 5～60 cm as independent variable and SFV as dependent, by stepwise regressing, multiple linear equation was established with a significant regression test.

The heat pulse technique was applied to study the variation of the stem sap flow of individual plant of Populus euphratica in different direction and depth of trunk in the Ejina oasis in the lower reaches of Heihe River. The results showed that the sap flow velocity increased with increment of depth and arrived at the maximum in 15 mm, and subsequently decreased gradually. The closer the point was to cambium, the earlier the sap flow moved. In four direction, the sap flow velocity in the south and west was more than that in the north and east; The sap flow in the south moved earlier and dropped more quickly than that in the west; The sap flow velocity was similar in the north and east. Based on it, the water transportation of near-mature P. euphratica stand was calculated using stem area as a scalar. There was a high correlation between the stem area of P.euphratica forest and diameter by power function. So the stem area of forest could be calculated by the distribution of diameter measured in the field. The water consumption of near-mature P. euphratica forest in the lower reaches of Heihe River in the growth season from May to October was 3 172 m³·hm^-2 by measuring the sap flow flux of individual plant with heat pulse technique.

betA is a gene encoding choline dehydrogenase. In the previous work, 13 betA transgenic Populus simonii×P.nigra plants were obtained. In this experiment, 9 transgenic plants were chosen for salt tolerance test. Transgenic and untransformed control plants were treated with 0, 100, 140, 170, and 200 mmol·L^-1 NaCl for different period of time. After these plants were treated for 2, 7, 12, 17 and 22 days, the betaine content of transgenic plants and untransformed control plants were determined, respectively. After the transgenic and untransformed control plants were treated with salt for 60 days, plant height and index of salt damage were determined. The results of ANOVA and multiple comparisons showed that the betaine content between transgenic and untransformed control plants was statistically different. The betaine content in transgenic plants was 27.1% higher than that in untransformed control plants. The index of salt damage in transgenic plants was 15.8% lower than that in untransformed control plants. And the plant height of transgenic plants was 44.1% higher than that of untransformed control plants. Based on the growth rate and the salt tolerance, T1, T4, T5 and T6 transgenic lines were identified as plants with high salt tolerance and fast growth.

The intermediate cutting intensity experiment was conducted in the Cunninghamia lanceolata stands at the age of ten on Zaoxia Forest Farm of Fengxin County, Jiangxi Province in June, 1976 and was finished in October, 1996. It lasted twenty years. The position research and randomized block design with three replicates were adopted. The studies indicated that the volume of the stands with different intermediate cutting intensities was in the normal distribution according to the distributive law of diameter classes and there was peak value close to the small-diameter class position. The volume of the stand large timber and its proportion increased evidently with the increase of the intermediate cutting intensity, but the small wood situation was contrary. The middle wood volume is not obviously different among the intermediate cutting intensities. The standing timber outturn accounts for 90%～95% of the total stand outturn and 5%～10% for the intermediate cutting trees and the withered and damaged trees. The intermediate cutting can't effectively enhance the total stand outturn and the periodic increment during the twenty years after the cutting. The strong intermediate cutting extremely and evidently increased the large timber outturn as compared with the control, but the small wood was on the contrary. The large timber outturn of the moderate and weak intermediate cutting also increased evidently as compared with that of the control, but the middle wood outturn is not significantly different among the intermediate cutting intensities. The total output value and standing timber output value of 30-year-old stands and their periodic increment during the twenty years from different intermediate cutting intensities were those from the strong>those from the moderate>those from the weak>those from the control. Those from the strong were extremely and evidently larger than those from the control, and those from the moderate and weak were evidently larger than those from the control. That the standing timber output value (and its periodic increment) of the intermediate cutting stands was evidently larger than that of the control was the result of the large timber output value increase. The twenty years after the cutting were divided into four periods according to the change of the annual mean output value and its periodic annual mean value of the stands, I.e.the ascendant period, the peak period, the peak continuation period and the descendant period. The studies proposed that the higher economic benefit can be obtained by determining the final cutting time of C.lanceolata forests according to the timber product market value and its corresponding economic benefit. The final cutting time for the stands with the different intermediate cutting intensities: 24 years for the control, 30 years for the weak or moderate intermediate cutting and 30～35 years for the strong intermediate cutting.

10 morphologic characteristic indexes of seeds and legumes in Gleditsia sinensis were investigated in 7 locations in China. The result showed: There were significant differences among morphologic characteristics of individual tree from the same population, and an extremely significant difference existed among those from different populations except width of legume, length of seed, and length to width ratio of legume. The mass, length, width and length to width ratio of legume showed a south-north variation at a same longitude; Width to thickness ratio of legume, and length to width ratio of seed were proved a west-east variation at a same latitude; Southwest_northeast variation existed at the thickness of legume, length of seed and length to width ratio of seed; There was no significant trend of geographic variation in 1 000 seeds' mass, which were mainly related to the altitude of distribution locations, water, solar radiation, the length of frost-free period and the burning hot.

Alkaloids distilled from the weed Sophora alopecuroids was bioassayed with Plagiodera versicolora for their antifeedant effects. The feeding of the insect was strongly inhibited by the total alkaloids and their monomers, with the higher concentrations having stronger antifeedant effects. In choice bioassays, the food intakes of the insect decreased rapidly with the higher concentrations of the total alkaloids. There were no differences among the food intake of non_treated leaves. However, the total food intake decreased significantly with increasing of the alkaloid concentrations. Among the six alkaloids tested, aloperine and sophoramine had stronger antifeedant effects on Plagiodera versicolora. In the non-choice experiments, 99.4% antifeedant rate was observed when the leaves were treated with 5 mg·mL ^-1 aloperine, while in choice bioassays, sophoramine antifeedant showed stronger antifeedant effects with the antifeedant rate 91.7%.

There was significant difference in damage between four varieties of plum through the methods of outside investigation and variance analysis. The enzyme assay of carboxylesterase and glutathione-S-aromatic transferase of Hoplocompa fulviconis larva feeding on four plum varieties were conducted. Results showed that there was notable difference between enzyme activity. Electrophoresis of carboxylest and peroxidase also showed the difference. Relationship was existed between enzyme activity and pest-resistance.

Hylobitelus xiaoi is a new kind of trunk pest that was found in Hunan and mainly damaged some pine species, such as Pinus elliottii、P.taeda、P. massoniana、P. taiwanensis and P.armandi. The insect had one generation within two years. The fastigium of imago was between middle ten-day of April and middle ten-day of May, the fastigium of pupa was in the last ten-day of September. The best period of catching insect by manpower was between the first ten-day of September and the last ten-day of November. The method of daubbing shank with pesticide decreased 30% insect inbreaking and the control effect of injection with pesticide was 95%.

Species and quantities of birds at 20 separating green belts of Beijing urban area were investigated between July 2003 and July 2004. Totally 90 bird species in 34 families and 16 orders were recorded, in which Accipiter nisus, Falco tinnunculus, Aix galericulata and Athene noctua were protection animals at the national level Ⅱ. The results showed that differences between structure characteristics of bird communities at different green belts, such as the biodiversity, the evenness and the similarity, were prominent, and plant species, plantation structures and bird biodiversities were closely related. The results implicated that returning environments to their natural states, improving space differences and reducing interferences from human beings would increase biodiversities and densities of the bird communities. Based on the results, suggestions on selecting and arranging of trees in greenbelts and daily management of the greenbelts were brought forward.

Two categories of spread models used for forest fire simulation, namely contiguous cellular model and wave propagation model, were strongly complemented each other in their advantages and limitations, which was utilized in the paper to design a spread model based on computer graphic techniques. In the new model, states of fire spread are expressed as a predefined gray level image. A series of fire shapes stored in metagraphic set are written to the gray level image according to given rules of raster operation while simulating the wave propagation of fire spread. Scan-line flood-fill algorithm is used to deal with the spread near some geographical elements with complex topological relations. Projection of fire shapes is translated into the combined transformation of graphic rotation and shear. The advantages and deficiencies of the model are discussed, including its effect on local distortion and aberration. By primary theoretical analysis and a calculation case, it is deduced that the new model can accomplish the simulation for forest fire faster than the previous models by more than one order of magnitude, while other performances of simulation are highly improved as well. Therefore, it can provide forest fire fighting with precise and overall predicted diagram of fire development in real time, not restricted by complexities of fire behaviors or geographical elements.

Response of ring width and ring density to climate variance was studied by theories and techniques of dendrochronology including response functions analysis and multiple regression analysis for Platycladus orientalis in Beijing, China. The results showed that ring width series and ring density series of P. orientalis was sensitive to climate variance. The climate response models were established with mean monthly temperature and total monthly precipitation from the preceding November to the current October. The models explained 58.45% and 77.81% of the ring width total variance and ring density total variance, respectively. It was found that ring width has a significant positive response to precipitation and a significant negative response to temperature from June to August during the current growing season. The reverse was true to the ring density, it had a negative response to temperature and a significant positive response to precipitation. Response of ring width and ring density to climate variance was evident especially July. The results indicated both the ring width and the ring density of P. orientalis are very useful variables for the study of dendroclimatology.

The zero-span tension technique, used widely in papermaking industry, was introduced to wood science research in China, and used to estimate rapidly the longitudinal tensile strength of tracheids of Chinese Fir plantation wood. It was found optimum thickness of samples and clamping pressure for zero-span tension was 80 μm and 70 psi respectively. Statistical analyses indicated stable increase of tracheids tensile strength from bark to pith, while no significant variation was observed along tree height from 1.3 m to 7.3 m. Therefore, it was inferred that zero-span tension could be used as a novel and reliable method for assessing the axial tensile strength of softwood tracheids.

Dynamic mechanical analysis (DMA) could be used to evaluate the effect of softening treatment with heat and water.The results of DMA showed that storage modulus (E′) of softening treatment bamboo at 120 ℃ for 30 min was apparently decreased compared with that of no softening treatment bamboo. The storage modulus (E′) of bamboo at 40 ℃ after softening treatment at 120 ℃ for 30 min reduced 60.4% compared with that of no softening treatment bamboo. That is to say that the effect of softening treatment at high temperature was obvious. Glass transition temperature (T_g) of no softening treatment bamboo was 119.8 ℃, while glass transition temperature (T_g) of softening treatment bamboo at 120 ℃ for 30 min was 88.4 ℃, T_g of softening treatment bamboo at 120 ℃ for 30 min decreased 26.2% compared with that of no softening treatment bamboo.

The chemical compositions and pulping properties of Larix kaempferi in different tree ages were investigated. In results, with the growing of L.kaempferi, the total carbohydrate decreases, water extractives including cold water extractives and hot water extractives increase, and 1%NaOH extractives also increase; glucosan and xylan decrease, however, galactosan increases. After investigating the influence of alkali charge, sulfidity and time at max. temperature on L.kaempferi kraft pulping, we found the optimal technical conditions of pulping are that alkali charge(to Na₂O) is 21%, sulfidity is 25%, the max. temperature is 170 ℃ and time at max. temperature is 2.5 h. Furthermore, with the growing of L.kaempferi, the trees become harder to cooking, alkali consumption and kappa number of pulp increase; the physical property of the pulp of 12 years old L.kaempferi woods are better than those of the two other aged trees. So through a analysis the result of chemical compositions and pulping properities of L.kaempferi by synthesis, we can conclude that 12 years has an advantage over those aged more than 20 years in papermaking for L. kaempferi.

The concepts and several models of niche breadth and niche overlap of a species or population were given. Reviewing and analyzing the models for measuring the niche breadth and niche overlap, which were put forward by different authors. Although so far in China, most of the studies on the niche parameter limited in the single ecological resource axis, along the development of the methods for multidimensional niche measurement, the research on the multidimensional niche breadth and niche overlap would be paid more attentions and would become the main stream.

China is rich in Spiraea resources about 70 species distribute and whose distribution is widely. The plant resources of Spiraea not only have excellent ornamental value, but also some of them also have cultivation advantages for example, adaptation to cold climate in the North, they are one of the hard-won flower shrubs in northern landscaping, but their resources and application have not been paid much attention. This paper summarized the distribution of Spiraea species and its varieties in China, some familiar species,cultivars, their characters and application in landscaping were introduced, and some fine species were recommended, the prospect of landscaping application was also presented finally. Compared the introduction and application of Spiraea plants with England, America and Germany etc., the intensive study and extensive utilization of Spiraea plant resources should be strengthened urgently in China.

This article attempts to make an introduction to the actual research of Paphiopedilum, paying more attention to its wild resources, cultivation and propagation. Some existing problems on Paphiopedilum, especially its hybridization, breeding and sustainable exploitation, are also discussed. Finally, a series of suggestions on Paphiopedilum resources utilization are put forward.

This paper presents an overall introduction of the recent developments on wood preservatives, treatment methods, modification technologies, environmental characteristics of wood preservation, and so on. On the basis of these, the major directions of wood preservation research are put forward. Water-borne preservatives are dominant now and will be in the near future, but the future wood preservatives are predicted to be some non-metal organic preservatives with superior properties. The development of wood preservation treatment methods is focused on increasing the treatability of preservatives in wood, accelerating the fixation reaction between preservatives and wood, and developing new treating processes in response to new preservative systems. The application of heat treatment and chemical modification to improve the durability of wood was also discussed. As to the environmental characteristics, the LCA (life cycle analysis) method was introduced and the methods of recycling of CCA treated waste were introduced briefly. This paper also gave a brief introduction on the associations and organizations of wood preservation as well as the wood preservations standards. The objective of this paper is to update the knowledge of wood preservation for the researchers and industries in China. It can help to set up the strategy of developing the wood preservation technologies in the needs of Chinese wood species and market, and then utilize the domestic wood resources more scientifically and efficiently.

Plant utilization of phosphorus in black calcareous soil was studied in Bidens pilosa, Mahonia fortunei and Cupressus funebris. Soil pH value, available phosphorus content, the distribution and transformation of inorganic phosphorus in rhizosphere and non-rhizosphere soils of these three plants were measured. Phosphorus content of plant was also measured and was 3 475, 2 609 and 3 466 mg·kg^-1 in B. pilosa, M. fortunei and C. funebris, respectively. The pH value in rhizosphere soil was significantly lower (P<0.05) than that of non-rhizosphere in B. pilosa (7.35 compared with 7.47), M. fortunei (7.47 compared with 7.67) and C. funebris (7.42 compared with 7.49). Available phosphorus of B. pilosa was accumulated in rhizosphere soil, but those of the other two species in rhizosphere soil were decreased. Compared with the content in non-rhizosphere soil, the contents of Ca₂-P and (Ca₈-P+Fe-P+Al-P) of B. pilosa in rhizosphere soil were increased by 0.89% and 2.13%, respectively, while the content of (Ca₁₀-P+O-P) was decreased by 3.03%, the total content of inorganic phosphorus of B. pilosa in rhizosphere soil was lower than that in non-rhizosphere soil. The content of (Ca₈-P+Fe-P+Al-P) of C. funebris in rhizosphere soil was increased by 0.92%, while the contents of Ca₂-P and (Ca₁₀-P+O-P) were decreased by 0.09% and 0.83%, respectively. The total content of inorganic phosphorus of C. funebris in rhizosphere soil was lower than that in non-rhizosphere soil. The content of Ca₂-P of M. fortunei in rhizosphere soil was unchanged, the content of (Ca₈-P+Fe-P+Al-P) was decreased by 1.29%, and the content of (Ca₁₀-P+O-P) was increased by 1.29%. The total content of inorganic phosphorus of M. fortunei in rhizosphere soil was higher than that in non-rhizosphere soil. The results showed that B. pilosa could decrease the pH value of the rhizosphere soil and activate (Ca₁₀-P+O-P), elevate the level of available phosphorus, effectively absorb and accumulate phosphorus from the soil. Utilization of phosphorus in B. pilosa was therefore stronger than that in the other two plants.

The article tested the phenolic substances by HPLC and tartaric acid-Fe spectrophotometry, analyzed the activities of SOD, POD and PPO in female and male tree leaves of Fraxinus mandshurica. Comparation of the components and contents of the phenolic substances and the tendency of the activities of oxydases between sexes were made. The results suggested that the total amount of water soluble and methanol soluble phenolic substances in male leaves was remarkably higher than that in female during the growth season, furthermore there was significant difference in phenolic composition between different sexed leaves. The activities of SOD and POD in male and female were significant different especially in May, and the significance also exists among seasons. Determination of these differences laid both theoretical and practical foundation for further research on sapling sex identification of this tree species.

Lidar (light detection and ranging) remote sensing is a breakthrough of active remote sensing technology in recent years. It has shown enormous potential for forest parameters retrieval. Lidar remote sensing has the unique advantage of providing horizontal and vertical information at high accuracies. Especially it can be used to measure forest height directly with unprecedented accuracy. Large footprint lidar has demonstrated its great potential for accurate estimation of many forest parameters. The geoscience laser altimeter system (GLAS) instrument aboard the ice, cloud and land elevation satellite (ICEsat) has acquired a large amount of data including topography and vegetation height information. Although GLAS' primary mission is the topographic mapping of the ice sheets of greenland and antarctica, it has potential use over land, especially for vegetation height extraction. These data provide an unprecedented vegetation height data set over large area. After a general discussion of GLAS waveform pre-processing, the waveform length extraction method has been developed. Then the waveform length from GLAS Laser 2a data in the northeast China was calculated. The waveform length map was analyzed together with land cover map from Landsat ETM+. The waveform length shows good accordant with land cover types from Landsat ETM+ data. As for forest area, the waveform length map contains much more information about forest height information, which can be used to inverse other forest parameters quantitatively together with other remote sensing data.

With fixed periods forest resources inventories and wide application of remote sensing,GPS technologies in forestry, large amount of spatial forest data have been collected in various forest resources bureaus. It is an urgent task to fully use these valuable spatial data to serve the national economic development and ecological construction. The expensive commercial geospatial software constrained small and middle-size companies to publish their spatial forest data. Fast development of open source software in the last decades provides an alternative solution to the commercial software. In the paper we developed a WebGIS based spatial forest information sharing system on county level with open source software FireFox, Apache Http Server, UMN MapServer and PostGIS/PostgreSQL. The system adopted four-tier architecture: client, Web server, application server and database server. The users can render the overlay information of spatial forest data layers, execute zooming in, zooming out, panning, and information querying functions. The system can provide most functions that commercial WebGIS has. It is suitable for small and middle-size companies which have limited budgets for developing WebGIS based spatial information sharing system to publish and share spatial information.

Effects of the extracts from selected bamboos on the growth and the activities of the digestive enzyme and arbaxylesterase of Helicoverpa armigera larvae were reported in this paper. The results showed that the extracts from Pleioblastus juxianensis, Bambusa multiplex, Brachystachyum albostriatum show strong growth disrupting effects on tested pest. The activities of the digestive enzyme in the larvae of Helicoverpa armigera fed with extract of Pleioblastus juxianensis, Bambusa multiplex, Brachystachyum albostriatum were higher than the control treatment, Thereinto, the activity of protease changed largest, that of amylase larger, and the activity of lipase changed a little. The activity of arbaxylesterase in the larvae fed with extract of Pleioblastus juxianensis, Bambusa multiplex, Brachystachyum albostriatum was inhibited, the relative enzyme activities after 3 days of which were 0.626、0.637、0.602 folds compared to CK, respectively. The effect on the enzymes in Helicoverpa armigera larvae was reduced with the treatment time.