We assessed the natural recovery after commercial logging with different manners, including repeatedly logging, selective logging, and managed selective logging in montane rain forests of Bawangling on Hainan Island. Our result showed that commercial logging enhanced species abundance of recovery communities in the tropical montane rainforest, due mainly to the increase of species richness of small stems (<10 cm DBH). The stems in logged forests were significantly more than old-growth forests, but the basal area of logged forests was apparently less than old-growth forests. Rates of species accumulation of saplings and young trees in forests after logging were less than those in old growth forests. After approximate 20-25 years of succession, the community structure of forests after managed selective logging was similar to the old-growth forest. The long-lived pioneer species richness, stems density, and basal area increased significantly in the forests after logged, especially after repeatedly logging. However, there was little variation in species richness proportion of late succession and shade-tolerant species among different forest communities. Those logged forests with selective logging and managed selective logging had higher recovery potential and rate, but it took time to recover to pre-logged forests level.

Characteristics of CO₂ flux were investigated by using the data collected from an open path eddy covariance system and an automatic weather gradient system in a 13-year-old Chinese fir plantation ecosystem in Huitong County, Hunan Province, in 2008. The results showed that there were pronounced diurnal and annual variations in CO₂ flux in the Chinese fir plantation. In clear days, mean duration of negative CO₂ fluxes decreased from summer, spring, autumn to winter, and the biggest mean daily carbon dioxide flux range and the earliest time of the average minimum carbon dioxide appeared in summer, followed by autumn, spring and winter. The Chinese fir plantation ecosystem had a negative monthly CO₂ flux that acted as a carbon sink except for January and February. The minimum accumulated monthly net carbon ecosystem exchange (maximum carbon sink) was -53.0 g C·m^-2 occurred in June. The annual net carbon ecosystem exchange amounted to -255.3 g C·m^-2. The CO₂ flux was closely related to several meteorological factors including photosynthetic active radiation, air temperature and soil temperature. The Michaelis-Menten model could be used to express the relationship between CO₂ flux and photosynthetic active radiation in daytime, however the model parameters varied apparently with different temperatures (P<0.05). The CO₂ flux at night showed an exponential relationship with soil temperature at 5 cm depth(P<0.05).

Based on questionnaires to 30 experts, single factor analysis was conducted respectively on the areal types of genera, the species status, prior protection species, relict genera of glacial epoch and harmful species by using the Delphi method. Furthermore, the wetland spermatophyta diversity in Hangzhou was assessed with the fuzzy comprehensive evaluation method. The assessment results were as follows: the single factor areal types of genera was rated as ‘very good’, the species status as ‘good’, prior protection species as ‘neutral’, relict genera of glacial epoch as ‘good’, and harmful species as ‘neutral’; The results in the integrated assessment that the wetland spermatophyta diversity in Hangzhou City was ‘good’, which indicated that the wetland spermatophyta had played a very important role for ecosystem functioning and services in Hangzhou City.

Fallen woods of Pinus tabulaeformis and Toxicodendron vernicifluum were used to study the decomposition process. According to an international classification, nutrient contents of 6 elements (C,N,P,K,Ca,Mg) in five decomposition classes were measured in Huoditang forest region in the Qinling Mountains, and the elements in the soil were also analyzed. The results showed that there were no significant differences among C contents in the decay classes of P. tabulaeformis, but the C content of T. vernicifluum decreased significantly with decaying. N obviously accumulated in the Ⅴ decay class in P. tabulaeformis and T. vernicifluum. There was no significant difference in Mg among the decay classes in P. tabulaeformis, while Mg significantly increased at the late stage of decomposition in T. vernicifluum. No differences were found in P, K and Ca among the decay classes of P. tabulaeformis and T. vernicifluum, however with the decomposition of P. tabulaeformis and T. vernicifluum, the contents of P and Ca linearly increased, the content of K linearly decreased. With the increase of soil depth, the content of soil C under fallen wood decreased significantly, however no difference was observed in K, Ca and Mg. The content of soil C increased significantly from decay Ⅰ to Ⅴ, while the N, P, Ca and Mg were similar. This research reveals the change pattern of various nutrients during the decomposition process of fallen wood, which would be helpful for measurement-making of promoting the nutrient cycling and forest regeneration of forest ecosystems in the Qinling Mountains.

Groundwater is one of the most important factors in desert ecosystem. The objective of this paper was to study impact of groundwater depth on height growth and the coverage of Nitraria tangutorum under the conditions with different atmospheric humidity. The transit dry area from the desert to oasis and the humid area along the yellow river bank between the oasis and the yellow river on the northeast of Ulanbuh desert were selected as site area. After collecting the data by using the contiguous quadrats, the groundwater depth was divided different layers based on 100 mm. The results showed that both the groundwater depth and the atmospheric humidity had effects on the height growth and coverage of N. tangutorum. In the dry area, the coverage and height of N. tangutorum showed an exponential growth with the increase of groundwater depth. Both the best groundwater depth range for N. tangutorum growing in cover and height were 2 500-9 000 mm according to the curve fitting. In the humid area, both the cover and height of N. tangutorum showed a Gaussian graph with the increase of groundwater depth. Moreover, the height growth adapted wider groundwater depth range than the cover. The best groundwater depth range was 1 000-9 000 mm for height growth and 2 000-7 500 mm for cover according to the curve fitting.

The spatial distribution of fine root biomass, specific root length(SRL), root length density(RLD), the root surface area index of the 10-year-old Robinia pseudoacacia plantation were investigated in hilly Loess Plateau region, and relationships between these root parameters and the soil environment factors(e.g. soil moisture content, soil temperature and soil bulk density) were analyzed. The results showed that, 1) the amount of fine roots decreased with depth of soil from 0 to 180 cm (the soil was divided into five layers; a, b, c, d and e layer). The change of the fine root biomass, RLD and the root area index with the depth could be described by a negative exponential function. The roots distributed mainly in the 0-60 cm soil layers and the peaks of the three parameters all appeared in the 0-20 cm, accounted for 42.72%, 44.44% and 47.14% of those amounts from 0-60 cm soil layers, respectively. SRL did not decrease much with soil depth, and even appeared reverse in the 80-140 cm soil layers. The relationship between the SRL and the soil depth could be described by a cubic polynomial. 2) With increasing horizontal distance from the tree trunk, the fine root biomass, RLD and the root area index decreased gradually. The SRL increased in the range of 40-80 cm and 120-160 cm respectively. 3) The environmental factors strongly influenced the root distribution, and the influence degree was in an order: Soil temperature>soil moisture content>soil bulk density. A multivariate linear regression model was established between root parameters and environmental factors and the model achieved 95% significant level.

In order to achieve precociously flowering of poplar and shorten the genetic and breeding period, we studied factors affecting genetic transformation of FT 1 gene controlled by Heat Shock Promoter in hybrid aspen clone (Populus tremula×P. tremuloides) and optimized the Agrobacterium-mediated transformation conditions. FT 1 gene was transformed into hybrid aspen through optimized transformation protocol and the 2-3 months transgenic plants were successfully induced to precociously flower by heat shock. The results showed that regeneration frequency of kanamycin resistant plants of hybrid aspen were significantly affected by pre-culture of leaf disc, Agrobacterium concentration, incubation duration,and co-culture duration. Optimized transformation protocol was as follows: leaf discs were pre-cultured for 6 days on the callus-induction medium, incubated for 60 minutes in Agrobacterium solution to reach to the OD₆₀₀ value of 0.5, and then co-cultured for 2 days. According to this protocol, regeneration frequency of kanamycin resistant plants can reach to 29.84%. Expression of FT 1 and precociously flowering of transgenic plants were induced by heat shock treatment of 37 ℃, 1 hour per day for 3 weeks. The size of transgenic plants was a limiting factor that affected the precociously flowering induced by heat shock, and plants with height less than 20 cm didn't show precociously flowering when induced by heat shock. Heat shock can induce more normal flowers, but extensive aberrance was still presented.

Expansins are a kind of cell wall binding proteins, and can induce cell wall extension without any activating protein at a certain pH condition. On the basis of ESTs isolated from a xylogenesis-specific cDNA library of Chinese Fir(Cunninghamia lanceolata), we successfully cloned 3 full-length expansin genes using RLM-RACE. Sequence analysis showed that ClEXPA 1 cDNA was 1 033 bp in length capable of encoding 247 amino acids, ClEXPA 2 cDNA was 1 374 bp in length capable of encoding 268 amino acids, and ClEXLA 1 cDNA was 1 023 bp in length capable of encoding 272 amino acids. Phylogenetic reconstruction indicated that ClEXPA 1 and ClEXPA 2 belonged to α-expansin (EXPA); whereas ClEXLA 1 belonged to γ-expansin (EXLA). Expression patterns of ClEXPA 1 and ClEXPA 2 were similar, with high transcript levels detected in cambium region, and intermediate levels observed in needle and shoot tip; very low levels in mature xylem, and almost no transcript in root and pollen. In Contrast ClEXLA 1 had different expression pattern: high transcript levels were observed in cambium region and needle; intermediate levels were detected in shoot tip and xylem; low expression levels in pollen and barely detectable in root. These isolated genes would provide an important pool in systematically studying the expression, function and regulation mechanism of expansins during wood formation.

SSR markers were used to characterize the genetic variance and relationships among 264 elite genotypes of Japanese Larch (Larix kaempferi), selected from the first-generation trials, which will be used as materials for second-generation breeding. A total 1 620 expressed sequence tags (ESTs) from larch were collected to develop simple sequence repeats (SSRs) by data mining. Totally 58 contigs with 67 SSRs were identified from all these contigs, and accounted for 3.58% of the total number of ESTs. Seven polymorphic simple sequence repeat (SSR) markers were developed and characterized; five of the loci had the advantage of high cross-species transferability to other larch species that naturally occur in China. These polymorphic and cross-taxon markers should be valuable for genetic studies on Larix. Six of these EST-SSR markers and four gSSR markers were used to detect genetic diversity of the elite population selected from the northern subtropical region. The average number of alleles and effective alleles per locus was 4.6 and 3.1, respectively. The means of expected and observed heterozygosities were 0.590 2 and 0.570 2, respectively. The genetic similarity coefficients between all elite tree individuals ranged from 0.172 5 to 0.966 7; Nei's gene diversity and Shannon's information index for this population were 0.569 1 and 1.096 6, respectively. The research suggests that these elite trees have good potential to establish second-generation breeding population with high genetic diversity.

Sixteen Chinese chestnut (Castanea mollissima) varieties collected from different areas of China were used to study the effects of starch-surface-lipid on pasting property of chestnut starch. RVA-pasting viscosity of chestnut starch with de-fatting treatment gradually increased, and reached a peak during the whole warming period at 50 ℃ for 1 min. However, the RVA-pasting viscosity declined to the lowest when starch was warmed at 95 ℃. A following cooling at 12 ℃ brought, the RVA-pasting viscosity to slowly increased again until the whole process ended. Moreover, curves of the RVA-pasting viscosity in chestnut starch, expressed four types in terms of their shapes. The de-fatting treatment did not change shape of curve, but modified the characteristic values of the RVA-pasting viscosity quite largely. The three characteristic values ‘PEAK’, ‘THROUGH’ and ‘FINAL’ increased while the characteristic value ‘PASTING TEMPERATURE’ decreased after the chestnut starch lost its fat. De-fatting of chestnut starch did not affect the ‘PEAK TIME’ of the RVA-pasting viscosity, but interfered the ‘BREAKDOWN’ and ‘SETBACK’ of the RVA-pasting viscosity, depending on chestnut cultivars. When the starch-surface-lipid content was in a range 0.96% to 4.50% the pasting property of chestnut starch was obviously affected regarding to ‘PEAK’, ‘THROUGH’, ‘FINAL’ and ‘BREAKDOWN’ in the characteristic values of the RVA-pasting viscosity.

One-year-old seedlings of ten provenances (KM, SY, LY, LQ, CX, NJ, GY, NC, GL and HS) of Camptotheca acuminata were used to study their responses to NaCl stress. The growth and physiological and biochemical parameters were measured under treatments 3 saline concentrations including 0%, 0.2% and 0.6% NaCl ((NaCl/dried soil weight)×100%). The results indicated that 1) seedling height, base diameter and biomass tended to decrease and a ratio of roots to crown tended to increase with the development of salt stress, and the decrease in growth of LQ and CX provenances were the most; 2) under the NaCl stress, SOD activity, contents of MDA, soluble sugar, soluble protein and Na⁺ and Na⁺/K⁺ value increased but RWC declined,and contents of K⁺ and POD activity increased initially, and then decreased; 3) based on the total biomass of the provenances under the stress of 0.6% NaCl concentratior, the salt-tolerating capacity of the ten provenances was in the following order: LY>NC>GL>HS>SY>GY>KM>NJ>LQ>CX; and 4) stepwise regression analysis showed that contents of soluble sugar and MDA and ratio of Na⁺/K⁺ in leaves had a most significant influence on the total biomass, which could be used as a reference parameter for evaluating of saline tolerance of Camptotheca acuminata.

A cycling collection device was used to collect root exudates of poplar I-107 (Populus×euramericana ‘Neva’) seedlings grown under N or P deficiency conditions. The ultrahigh performance liquid chromatography (UPLC) was used to assay the amount of phenolic acids in the root exudates, to study the secretion dynamics of several phenolic acids. The results showed that some phenolic acids, ie. p-hydrobenzoic, vanillin, benzoic acid and cinnamic acid, were able to be secreted from roots of the seedlings grown under normal and nutrient deficiency conditions. However, nutrient deficiency could significantly promote the secretion of phenolic acids from the roots. Under nitrogen-deficient conditions, the amount of p-hydrobenzoic acid was 125%-263%, vanillin 201%-316%, benzoic acid 230%-332%, cinnamic acid 138%-188% of that in normal conditions, respectively. The secretion amount of phenolic acids increased with the stress duration. But, there was no significant difference among three culturing periods (0-5 d, 6-10 d, 11-15 d). Under phosphorus-deficient conditions, the secretion amount of p-hydrobenzoic acid increased by 96%-124%, vanillin 58%-156%, benzoic acid 222%-734%, cinnamic acid 99%-328% in comparison with the normal conditions. Furthermore, the amount of benzoic acid and vanillin all increased with treatment duration under phosphorus deficiency conditions, while the amount of benzoic acid and cinnamic acid appeared increasing initially and then decreasing with treating time. Additionally, the average secretion rate of phenolic acids was significantly different between nitrogen and phosphorus deficiency conditions. The secretion rate of p-hydrobenzoic acid and vanillin under nitrogen-deficient conditions was faster than phosphorus-deficient conditions, while the secretion rate of benzoic acid and cinnamic acid was slower than phosphorus-deficient conditions. The secretion dynamics of phenolic acids reflected the effects of stress environments on the secretion of poplar roots, and shed light on the mechanism of their accumulation in the rhizosphere soil.

The effect of different treating time with the pulsed magnetic field (PMF) on the growth and infestation of Botryosphaeria dothidea was studied under a condition of fixed pulse rise time 10 ms. The results showed that short PMF treatment was able to effectively inhibit growth and infestation Botryosphaeria dothidea, and the longer time the treatment , the stronger the inhibition. With pulse treatment for 45 min, colony was inhibited by 54.11% in 48 h, and the browning index of poplar callus inoculation after 72 h was only 26.89%; With pulse treatment for 60 min, the inhibitory effect was best, and the colony all was dead. The observations with SEM revealed that the colony had the characteristics of uneven thickness, the mycelium stuck together, the surface wrinkled, branch and parts of hyphae even dried out. Based on TEM, after pulse magnetic field treatment, the cell wall became significantly thinner and the inner parts disordered and degraded, moreover the cell structure was destroyed seriously and intracellular vacuoles increased. In the meantime, the poplar callus cells structure was influenced to different degrees by B. dothidea, including deformation and disintegration of cell wall, decomposition of the layer, fracture of plasma membrane, plasmolysis; Cell organelles decomposed and deposited near cell walls, degradation of intracellular hyphae and cavum. The pulsed magnetic field had a strong inhibitory effect on the growth and infestation of B. dothidea and could change the mycelium ultrastructure.

The dynamic of radial growth of Cupressus funebris in Yunyang County, Three-Gorges reservoir area was assessed by dendroecological techniques. The residual chronology (RES) and standard chronology (STD) of C. funebris were developed through crossdating after filtering out the genetic factors which influence tree-ring growth using a mathematic model, and the relationship between radial growth of C. funebris and climate factors were analyzed. The result showed that there was a significantly negative relationship between the tree-ring growth and the mean temperature of current spring season. The radial growth was significantly and negatively affected by the mean monthly temperature in January and February. Additionally, there was no significant relationship between tree-ring growth and monthly precipitation, monthly humidity index. The correlation analysis between the occurrence of Chinolyda flagellicornis and STD also demonstrated that the total occurring area of C. flagellicornis and the infection rate of C. funebris were significantly correlated with the tree-ring growth. Finally, the correlation model of tree-ring width index and climatic factors was established by multi-factor regression for predicting growth of C. funebris.

Selection of dust-bathing sites used by brown-eared pheasant was studied by using a transect method in Huanglong Mountains Nature Reserve, Shaanxi, China from November 2006 to January 2007. Along the 8 sampling transects, 54 sites used by brown-eared pheasant and 96 random plots were set. Brown-eared pheasant preferred the dust-bathing sites located on lower slope, sunny slope, half sunny slope, upper slope side and ridge, avoided the sites on mid-upper slope location, shady slope and gully, and selected randomly vegetation type. Comparing with random plots, dust-bathing sites were usually set at lower altitude close to human disturbance, water source and edge of woods. On the sites, there were a small number of trees with small cover, diameter, and height, a small number of shrubs with small height and large cover, and abundant grasses with large cover and greater height that were noticeable. In Huanglong Mountains brown-eared pheasant frequently used caves as their dust-bathing sites, accounting for 35.19% of total dust-bathing sites. Dust-bathing sites in caves were relatively farther from human disturbance, lower visibility, and on steeper slopes, and had a big number of trees with large cover and small diameter, many shrubs with large cover and tall grasses. Distance to human disturbance and edge of woods, slope location, altitude, visibility, cover of shrub and number of trees were critically factors to discriminate the used sites and random plots. The overall classification model developed from those 7 variables was successful to distinguish dust-bathing sites from random ones at probability of 93.60%.

The characteristics of lightning fires from 1972 to 2005 and its relationships with Palmer drought severity index (PDSI) and Keetch-Byram drought index (KBDI) in Daxing’anling forest region were analyzed in this paper. The results showed that the lightning fire mainly happened from May to September. A peak of the lightning fires occurred in June, accounting for about 42% of the annual numbers. The maximum burned area happened in May and June, accounting for about 85% of the annual burned areas. Monthly dynamics of numbers and burned area of lightning fires could be expressed as one-humped curves. The monthly dynamics varied with drought indexes. A typical one-humped curve presented with KBDI and the driest months were from May to July, while a weak one-humped curve presented with PDSI, with May drier and June and July wetter. Annual numbers of lightning fires could be closely correlated with PDSI in September (R²=0.47, P<0.01) or KBDI in June and August(R²=0.57,P<0.01), and annual burned areas of lightning fires with PDSI in August(R²=0.20, P<0.01) or KBDI in June(R²=0.40,P<0.01). It was indicated that KBDI was more suitable for simulating the characteristics of lightning fires in Daxing’anling forest region than PDSI.

Taking the establishment of single-tree biomass equations for larch (Larix) of the northeast and Masson Pine (Pinus massoniana) of the south in China as the example, the goodness evaluation and precision analysis were studied in this paper. Firstly, based on the comprehensive analysis of various statistical indices for model evaluation, six essential evaluation indices were presented which proved to be feasible and effective through evaluating the tree biomass models of two species above. Secondly, according to basic assumptions of linear regression estimation and related formulas of confidence intervals for prediction, the approach to estimate confidence intervals of conditional mean and single predicted value of tree biomass models was provided, and the confidence intervals of tree biomass models of two species were determined. Finally, the Monte Carlo simulation was used for random resampling test, and the test results showed that examination of applicability based on validation samples was inadvisable, and the adequate procedure was to utilize all sample trees for constructing the model, not splitting into two groups for model construction and model validation, which could make full use of the information of entire sample and decreased the prediction error to the highest degree.

To evaluate the effectiveness of forest management model, the method which used the structure characteristics of virgin forest or zonal climax community as a template was presented from the technical advancement on the basis of the space utilization, species diversity, constructive species competition,stand composition and the production feasibility on the basis of the input-output production. The method was applied to nine management models of the Xiaolongshan forest area in Gangsu Province, China. The evaluation indicates that the selective cutting of natural arbor forest model (model 4) was the most effective forest management model, and the belt transformation of natural shrubbery model was evidently superior to the overall transformation of natural shrubbery model in transformation of natural shrubbery models. Besides, the Pinus armandii was the best in tree species selection, while the Larix kaempferi was the worst. The evaluation method presented in this study for the effectiveness of forest management model is concise and scientific which can reflect the technical advancement and incarnate the production feasibility at the same time.

Using knot analysis data of 95 sample trees in 19 sample plots of larch(Larix spp.) plantation in northeast Heilongjiang Province(5 sample trees were selected in each sample plot), the models for predicting knot variables, including knot diameter, angle and length, were developed based on the linear mixed effect model. The results showed that the knot diameter, angle and length increased as DBH increasing. When knot height increased, knot diameter increased firstly, and then decreased, and knot angle decreased gradually. The knot length increased with knot diameter increasing. Comparing with fixed effects model, the mixed effect based knot size models can obtain more accurate parameter estimates,the residual distribution of the model was more uniform, and the fitting precision of models were obviously improved(the R² value improved about 0.3).The results of independent validation showed that prediction precision of each model reached above 90%. Therefore, knot models developed in this paper can suitably describe the knots variation for larch plantation.

In the present work, hydrothermal-microwave treatment was used for juvenile and mature ash wood softened treatment. Ratio of longitudinal compressing, single and multi-dimensional minimal curvature radius were used to evaluate the softening result. XRD and FTIR were used for the characterization of surface composition and crystallinity, analyzing the effect of softened treatment on longitudinal compressing and bending curvature ash wood. The results showed hydrothermal-microwave treatment could soften ash wood and increase the number of hydroxyl groups on wood surface significantly. And it also led to microfibre tended to arrange orderly and the degree of crystallinity increased in the non-crystalline region , the hydroxyl of the sur-microfibre exposed, the hydrogen bonding enhanced and the width of crystal region increased in the crystal region. When the time of hydrothermal and microwave treatment is 140-150 min and 350 s respectively, the ratio of longitudinal compressing reached maximum, and the single and multi-dimensional radius reached minimum.

To determine feasibility of intensive short-rotation management of triploid hybrids of Populus tomentosa, wood basic density and chemical components were in detail investigated in 3-year-old short-rotation pulpwood plantations. The results indicated that there were extremely significant differences in wood basic densities within clones. There were also significant differences in wood basic densities within spacing. Wood basic density of 3-year-old pulpwood plantation ranged from 0.247 to 0.282 g·cm^-3. Significant differences were found in contents of pentosam, ligin, holocellulose and α-cellulose within triploid clones, and no differences in content of benzene-alcohol extractive of chemical components within spacing and interaction between clones and spacing. Content of phenol-alcohol extractive of 3-year-old pulpwood plantation ranged from 3.68% to 4.39%.Content of pentosan ranged from 12.86% to 13.47%. Content of ligin varied from 18.16% to 19.77%.Content of holocellulose changed from 74.91% to 77.61%. And content of α-cellulose varied from 40.28% to 43.49%.

The bending, tensile and compression properties of 596 pieces of Chinese Fir dimension lumbers with 45 mm×90 mm cross section on three visual grades, SS, No.1 and No.2, were investigated in this paper. The results showed: the mean values of modulus of elasticity (MOE), modulus of rupture (MOR), ultimate tensile strength (UTS) and ultimate compression strength (UCS) were shaping like "V" from grade SS, No.1 to No.2, and those test values of lumbers on grade No.1 were all similar or slightly lower than that of on grade No.2. The 5^th percentile value of those strength properties were observed to decrease from grade SS, No.1 to No.2, while there no significant change for MOE was observed among the visual grades. The values of MOR, UTS, and UCS had statistically significant differences on three grades at the 0.01 probability level. Moderately good correlation was observed between the mean values of MOE and the MOR, UTS, and UCS in the same MOE ranges, which can be quantified the relations of three main mechanical strengths when sample size was not big enough.

Nanocellulose crystal(NCC)was prepared from microcrystalline cellulose(MCC)by sulfuric acid treatment, and composite films were prepared from polyvinyl alcohol(PVA) as the matrix and NCC as the filler. Their morphology, size and thermal properties were characterized by field emission transmission electron microscopy(FETEM), atomic force microscopy(AFM), field emission gun environment scanning electron microscopes (FEGE-SEM), thermogravimetric analysis(TG)and differential scanning calorimetry(DSC). The results indicated that the diameter of NCC was about 2-24 nm, with the length 50-450 nm. From FE-SEM images, it could be observed that PVA /NCC composite films were created by casting from a water suspension to produce a homogeneous dispersion of NCC in the polymer matrix. But it showed some agglomeration when the filler loading reached to 7%, and the interaction between NCC and PVA decreased. TG and DSC analysis showed excellent interaction between NCC and PVA. The composite films filled with nanocellulose crystal exhibited improved thermal properties as compared to the neat PVA film. On the other hand, the thermal stability of the PVA composite films was decreased with filler loading increased to 7%.

In the paper, we managed to prove that there is the economics of scale in plywood production in Pizhou on the basis of data from Pizhou economic census (2008), and present some explains of its causes. We found that the scale disparity in return of capital was derived from the efficiency of organization and administration but not technique efficiency. And we have not got the proof that shows a lower resources utilization ratio in smaller enterprise.

Cable series selecting, ropeway cabling, designing calculation, selecting type and configuration of mechanical equipment and technology of installation and dismantling were researched systematacially in engineering design of skidding ropeway for thinning. Technology of "allowable load method" and steel tube backstay bracket for cable crane were applied in forestry ropeway engineering, "surplus length dispense with connection" technology for speed installing and dismantling closed tractive rope was presented. JP force increasing carriage with double(single)rounds and optimizing rope series which are mated with JS2-0.8 type mobile winch set were designed.

Peptide hormones are involved in plant growth, development, stress resistance and many other life processes, and especially play a key role as signaling molecules in the short-range cell-cell communication. The procambium/cambium cells continuously generate xylem and phloem cells through division and differentiation, while maintaining their own proliferation activity. Recent studies have shown that CLE peptide hormones and their receptor kinases could determine the vascular cambium cell fate through a unique signaling transduction mechanism, therefore they are important in regulating the development of vascular system. Focusing on vascular tissue, this review introduces the CLE peptide hormone signaling pathway in controlling and influencing the division and differentiation of procambium/cambium cells in Arabidopsis . It is still unclear how CLE peptides affect the initiation, maintenance and differentiation of vascular cambium cell in woody plants. However, with the poplar genome sequence information available, people will further understand those important genes controlling the proliferation and differentiation of cambium meristem cells in trees, and hence achieve the purpose of regulating the secondary vascular system development and improving the wood properties by using functional genomics research strategy.

After the terminal bud is set, the seedling biomass can still accumulate substantially and accordingly the nutrient concentration in the seedling declines in the fall. The dilution caused by biomass increase could be relieved by fall fertilization. Abroad, fall fertilization is widely applied for culturing many evergreen tree seedlings such as Picea abies, Picea mariana, Pinus taeda, Pinus elliottii, Pinus resinosa, Pinus ponderosa, Pseudotsuga menziesii, Eucalyptus globulus. However in China, just a few studies are referred to fall fertilization with the seedlings of Platycladus orientalis and triploid Populus tomentosa. In this paper, many aspects in the recent studies were reviewed, including the of the morphological and physiological mechanism happened in the seedlings regulated by fall fertilization, field performance of the seedling conducted by fall fertilization, as well as the system of the fall fertilization. Translocation of nutrients was specifically analyzed about how to regulate the seedling quality at nursery and subsequent field performance after the seedlings were applied fertilization in the fall. Differences were further discussed between the seedlings of evergreen and deciduous trees with fertilization in the autumn. Based on the aspects, the future in the study was prospected.

Study on wildlife habitats is one of the cornerstones of zoology; it can provide theoretical support and reference for resources management, artificial rearing and ex-situ conservation of endanger animals with insightful perspectives of the interaction between animals and habitats. This article reviewed comprehensively studies of bird habitats with aspects of methodologies, habitat selection and evaluation and habitat fragmentation. Traditionally, sampling techniques of strip sampling method and 0.04 hm² circular plot were most frequently employed by researchers. However, application of 3S technology by more and more ornithologists remarkably promotes research efficiency and enlarges the scope of bird habitats. Birds select their habitats mainly based on vegetation type, and other affiliated factors which vary according to spatial scale, seasons and phases of bird's life history. Based on the habitat selection, researchers can evaluate the suitability of different habitats, propose a reasonable rank and provide theoretical reference for birds' habitat conservation and restoration. Finally, the paper discussed the influence of habitat fragmentation on bird behavior, nesting success, breeding success and distribution of bird community. This article also predicted the trends of research object, method, content and other aspects of the domestic avian habitats.

In order to reveal the response of four broad-leaved arbors to climate change, we studied relationships between interannual variations of air temperature and various phenophases (i.e., seasonal biological events) of broad-leaved arbors species (Betula platyphylla, Juglans mandshurica, Ulmus pumila and Morus alba) in the Harbin, based on meteorological data from 1951-2008 and phenological data from 1963-2008. Results showed that the air temperature in Harbin had an increasing trend from 1951 to 2008, especially after 1978. The increase of the annual minimum temperature was greater than that of the annual maximum temperature and annual mean temperature. Annual precipitation slightly increased, but not significantly. In the period of 1963-2008, bud burst, beginning of leaf expansion and first flowering of the 4 species all shifted to 5.7 d, 10.2 d and 7.9 d earlier, respectively, and end of leaf-falling was delayed for 7.5 d. The pattern of phenological change was consistent with that of air temperature change. The phenophases earlier or later was mainly subjected to air temperature, especially the mean temperature of the same month and previous month when phenophase began. The phenophase had little correlation with the precipitation. When the mean temperature in March rose up by 1 ℃, Betula platyphylla, Juglans mandshurica, Ulmus pumila and Morus alba buds burst were advanced by 2.2 d, 2.1 d, 0.8 d and 2.3 d, respectively, beginning of their leaf expansion was advanced by 2.2 d, 2.4 d, 2.1 d and 1.7 d, respectively, and the first flowering was advanced by 2.2 d, 0.8 d, 2.2 d and 1.2 d, respectively.

In order to guide scientifically planting on forest floor in eucalyptus plantations, screen suitable plants, and understand allelopathic effects of eucalyptus trees with different young ages (1 a, 2 a and 3 a) on the understory species and growth germination rate and seedling growth of five species widely planted in the local region were measured after treatments with different concentration of aqueous leaf extract of Eucalyptus urophylla×E.grandis treatments with different concentration. The results showed that the leaf extract reduced seed germination rate and inhibited seedling growth of all five species, and had a stronger inhibiting effect on radical than hypocotyl growth. The species tested in this study had different sensitivity to the leaf extract. The inhibition rate of Lolium perenne, Sorghum sudanense, Phaseolus aureus, Phaseolus vulgaris and Glycine max was 56.85%, 54.58%, 33.48%, 20.81%, 16.01%, respectively, among which Giycine max and Phaseolus vulgaris were the most insensitive to the leaf extract. The allelopathy of the leaf extract was concentration dependent, increasing with increase of the concentration, and low concentration (0.01 g·mL^-1) had no significant influence on the species. Furthermore, the allelopathy aqueous leaf extract of E.urophylla×E.grandis to the five species had no significant difference with increase of their ages.

The evapotranspiration characteristics of the common lawn species of Poa pratensis and Festuca arundinacea in Beijing was investigated by the weighing method of Microlysimeter. The result revealed that the daily evapotranspiration of the lawn was high at noon and low in morning and evening, and the change pattern had appropriate ecology synchronism with solar radiation and other environmental factors. Daily mean evapotranspiration of P. pratensis , under full sunlight and half shade was 5.78 kg·m^-2 and 3.86 kg·m^-2 respectively. While the daily average of F. arundinacea , under full sunlight, half shade and all shade, was 4.41 kg·m^-2, 3.03 kg·m^-2 and 2.63 kg·m^-2 respectively. According to physical and physiological characteristics of the grass after withdrawing water, soil moisture content of the lawn could be divided into three grades, sufficient water supply(water potential -0.18~-0.06 MPa), slight water deficit(water potential -0.44~-0.18 MPa) and medium water deficit(water potential -1.06~-0.44 MPa). Reduction of sunlight and soil moisture content could reduce evapotranspiration consumption of the lawn. Compared with full sunlight and sufficient water supply, and slight water deficit could reduce evapotranspiration of P.pratensis and F.arundinacea by 62.0% and 47.0% respectively. Evapotranspiration of F.arundinacea in half shade and medium water deficit could reduce 76.0%. Control of water supply and sunlight for the lawn could reduce consumption of water and save irrigation water.

Fraction 8 of the extractants from semen pharbitidis was identified and its mechanism of biological activity against Tetranychus cinnabarinus was investigated. The main component of the extractant fraction 8 was detected with nuclear magnetic resonance (NMR), gas chromatography and mass spectrum (GC-MS). Influences of the main component on several enzymes activities such as glutathione-S-transferase (GSTs), acetylcholine esterase (AChE) and mono-amine oxidase (MAO), in T. cinnabarinus body were detected by using biochemical method. Results showed that the main component of the extractant fraction 8 was methyl linoleate. The methyl linoleate activated glutathione-S-transferase in T. cinnabarinus body, while it inhibited to various degrees acetylcholine esterase and mono-amine oxidase related to nervous system, and hence caused the death of T. cinnabarinus. Therefore the methyl linoleate has a good prospect developing into new pesticide.

Asian longhorn beetle larvae were fed on host plants and artificial diet to investigate the variation of cellulase, and the activity of exoglucanase and β-glucosidase were measured. The results showed that larvae fed on host tree under natural growth situation had a significant reduction in both endoglucanase and β-glucosidase activities. The activity of endoglucanase in the first and second instars was higher than the followed three instars, and the activities of β-glucosidase in the former three instars are higher than the followed two instars. This trend also occurred in the larvae fed on artificial diet. The activity of endoglucanase in the 10, 20 and 30 days of age larvae was higher than that in the 80, 100 and 120 days of age larvae, and the activities of β-glucosidase reached a peak in the 60 days of age larvae, higher than the 80, 100 and 120 days of age larvae. Therefore it is suggested that ecological control measures related to cellulase inhibitor should be carried out on the first two instars larvae. According to its biological characteristics, the best time for controlling through inhibiting the activity of cellulase would be from September to November.

Variety ‘taishanyulian’ is derived from an individual tree with natural drooping branches found in a Ginkgo germplasm resource garden, after grafting propagation experiment. The leaves have two types: one is a herringbone blade with a deep crack that reaches to vane base or near base; another kind of blade with a shallow or very shallow crack, narrow blade, fan-shaped or semiorbicular, leaf margin wavy or toothed shaped short crack. Female plants, female cone has a long stalk, stem distal end has 1-2 disk-shaped beads, each bead 1 ovule that develops into a seed. Seed is drupelike, kernel (i.e. Ginkgo) smaller, exocarp fleshy, with white powders. From October to November when fruits ripe, with yellow or orange color, smell. Testa is bony, white; and endotesta is membranaceous.