The plant community types and spatial differentiation of plant species diversity along the altitudinal gradient in the Habaxueshan Mountain, Northwest Yunnan was analyzed using quantitative methods based on the 72 quadrat data. The result showed that: The plant communities of Habaxueshan Mountain could be grouped into 6 vegetation types with the hierarchical cluster analysis and the non-metric multidimensional scaling. The plant species diversity in Habaxueshan Mountain was influenced more by "the mid-domain Effect" than "Rapoport's elevation rule". The altitudinal pattern of species richness generally presented the single hump pattern and fluctuated in mid-elevation zone; both Shannon-Wiener and Cody indexes presented the single hump pattern on the whole, and showed wavy fluctuation in mid-elevation zone. Generally,the altitudinal pattern of plant diversity in Habaxueshan Mountain presented a complicate feature which indicated the diversity of micro-habitat, and the complication also manifested by the alternative distribution and substitution effect of plant communities.

In this study, we used biomass regression model to estimate biomass of arbor forest, took carbon-included rate in different tree species as the transferring coefficient from biomass to carbon stock, and further summed a single tree to plot and weighted means to province level. The carbon storage of arbor forests in China were estimated based on original data of 7th national forest continuous inventory. In the same time, carbon storage of open forests, scatted trees and "four-sides" trees were estimated by weighted mean conversion factors, and carbon storage of bamboo and shrubbery were estimated by regression model. The results showed that most of the forest carbon storage was distributed in the southwestern and northeastern China. Arbor forests were a main body of forest carbon storage in China. Carbon storage of plantations was more than 15% of total arbor forests in China, and carbon storage and density of broad leaf trees were higher than that of conifer trees.

The C-FIX model was used to estimate the forest vegetation NPP of Heilongjiang Province from May to September in 2000 based on ETM+, DEM and meteorological data,and the estimated results were compared with the MODIS NPP products. The result showed that the gross NPP of forests in Heilongjiang from May to September in 2000 was 69.75×10¹² gC, with the greatest monthly gross NPP occurred in June; accounted for 27.23% of the total NPP from May to September. June, July and August were the main months for accumulation of NPP. The total NPP of forests was 60.99×10¹² gC, accounted for 87.44% of the total NPP from May to September; among which the total NPP of shrub land accounted for 10.41%; the gross NPP of open forest land accounted for 1.63%; and the gross NPP of other forest land accounted for 0.52%. The root mean square error was 17.12 between MODIS product value and estimated value, and the error of estimated NPP with the MODIS was from 3.92% to 5.85%.

In this paper a profile technique- DOMAIN was used to map potential habitat suitable for moso bamboo (Phyllostachys edulis). and to select the areas with low suitable habitat as pseudo-absences. Then a group discrimination technique-NeuralEnsembles was employed to predict the potential distribution of moso bamboo (hereafter termed hybrid model) based on pseudo-absences and true presences data. Sensitivity, Kappa and the area under the curve (AUC) values of receiver operator characteristic (ROC) curve were employed to assess model predictive accuracy. Meanwhile, we investigated the sample size effects of pseudo-absences generated by DOMAIN on model performance. We also compared model performance of hybrid model with single model-NeurnalEnsembles. Results indicated that the hybrid model could achieve a higher accuracy in simulating current distribution of moso bamboo in comparison to single model. Sensitivity and AUC were relatively independent from pseudo-absence sample size, but Kappa declined with the increasing pseudo-absence sample size. Climate change is likely to have dramatic effects on the potential distribution of moso bamboo, with the northward migration ranging from 33 to 266 km, and the area expansion by 7.4% to 13.9%.

Vegetation coverage, as an important part of the ecosystem, is closely related to the global climate and long-term economic benefits of the country. Meanwhile, vegetation coverage is an important parameter for the description and assessment of landscape or ecosystem. In the field remote sensing, application of vegetation index to describe vegetation coverage percentage is widely accepted and applied. In this paper, we took the delta oasis of Weigan and Kuqa rivers as research object. This study was based on the TM/ETM+ images of 1989, 2001 and 2006, and applied the ENVI, ArcGIS software as technology methods. The vegetation index of VBSI was used to estimate the model of vegetation coverage according to the dimidiate pixel principle, and the estimation precision was later approved to be up to 83.52%. Further, we produced the vegetation coverage graduation map of the delta oasis of Weigan and Kuqa rivers, and analyzed and appraised changes in its structure. The results revealed a pattern of spatial change in the vegetation coverage of the study area. Forest, grassland and farmland were three main land use types in medium-high and high coverage and played an important role in keeping vegetation cover. Forest area determined the changes of coverage area, while the other two land use types were definitely able to affect direction of the changes. Since forest, grassland and farmland played an important part in keeping regional vegetation coverage, it should be planned to continually plant trees, maintain grassland, protect farmland and control unused land in a long-term program. Finally, variation of vegetation environment quality from 1989 to 2006 was evaluated according to distribution of quantity and space condition rendered by plant cover digital image. By comparing plant cover grade images of the three periods with local statistics materials, this paper pointed out that the development of Wei-Ku oasis soil salinization was controlled by two important reasons nature and humanity. In conclusion, this study provided the reference for the protection of ecological environment in Wei-Ku oasis.

In this paper, forecast combination was introduced to improve stand basal area prediction accuracy and compatibility. A linear combination of two or more predictions may often yield more accurate forecasts than using a single model to the extent that the component forecasts contain useful and independent information. But it is very important to calculate weight coefficients for improving forecast combination. Based on the data of the Chinese pine in Beijing mountains, sum of squared errors method, variance-covariance method and optimal weight method were used to calculate weight coefficients of combined model. Results show that forecast combination for predicting stand basal area outperformed over the stand-level and tree-level models respectively, and meanwhile, stand basal area model based on the optimal weight method(R²=0.929 2) is superior to other two methods, and variance-covariance method(R²=0.929 1) is better than the sum of squared errors method(SSE)(R²=0.929 1).

Our objectives were to investigate fine root spatial distribution of Caragana spp. in three alley silvopasture systems which are composed of one shrub belt and two-rows with different belt distance(4, 6, 8 m). The three systems had intact structure and uniform growth status in similar sites. The roots were sampled by the way of excavation from one soil layer to another vertically, on the woodland soil profile. The results showed that root biomass(RB)of Caragana spp. concentrated near the shrubs, Caragana spp. root biomass density(RBD)of 4 m system was markedly greater than that of 6 m and 8 m systems in central soil of woodland. The results also showed that, Caragana spp. fine root length density(FRLD)and fine root surface area density (FRSAD) in whole woodland of 4 m system were greater than that in 6 m and 8 m systems. In the three systems, average FRLD and FRSAD, cumulate percents of fine root length and surface area in 0-40 cm soil, FRLD and FRSAD in central soil, all decreased as belt distance of systems increasing. In 8 m system, root concentrated layers were separated between Caragana spp. and herbaceous, and fewer Caragana spp. roots were superposed in central soil, because of fewer fine roots of Caragana spp. in topsoil and central soil than that in other systems. Consequently, interspecies competition between Caragana spp. and herbage, and intraspecies competition of Caragana spp, were more mitigative in 8 m system, than in other systems. It suggests that Caragana spp. alley silvopasture system with 8 m belt distance is comparatively feasible, in semi-arid areas of northwestern China.

In this paper, three factors of neighborhood pattern, neighborhood comparison and species segregation were taken to describe the spatial structure of a typical scenic and recreational forest in Longmenshan National Geopark of Sichuan Province. The SBE method was used to estimate the forest in terms of esthetics. A correlation model was built up by multiple regression technologies. The results showed that that there was obvious effect of neighborhood comparison and species segregation on scenic beauty estimation in the study area. This study provided a scientific basis for forest management by integrating ecological factors and aesthetic factors.

Most of natural Quercus variabilis forests in China have degenerated to be secondary forests after overexploitation and continuously cutting. Stump sprouting is the most significant asexual reproduction type in this kind of forests. In this study, 192 Q. variabilis stumps located in sunny slope and shady slope of Foping, Shaanxi Province, China, were investigated in order to understand the stump sprouting capability, sprout growth characteristics and the relationship between sprouting and stump. All stumps formed after small scale clear cutting conducted in 2007 winter. The results showed: 1)The sprout number per stump was more in sunny slope than that in shady slope, in contrast sprout growth amount(base diameter, height and crown width)were all greater in shady slope than those in sunny slope; sprout number had a negative relation with growth amount at similar environment conditions. 2)Sprout number per stump increased at first and then decreased slightly along with the increasing of stump diameter, and the stumps with their base diameter of 15-25 cm had the strongest sprouting capacity; and sprout growth amount increased with increasing stump diameter. 3)There was no relationship between stump height and sprout number, however, there was a positive relationship between stump height and sprout growth amount. 4)Base diameter of sprout declined along with the growing of sprout number per stump, sprout height showed an almost opposite tendency; sprout growth amount was influenced by sprout number more heavily in sunny slope than in shady slope. 5)The percentage of sprouting stump and sprout growth amount in both habitats all declined significantly after two years of cutting, moreover, sprouts in sunny slope had lower annual growth compared with those in shady slope. All the results implied that sprouting capacity was influenced by habitats condition especially irradiation, stump diameter and stump age(years after cutting); sprout growth were influenced not only by the factors described above, but also by stump height and sprout number per stump. Therefore, selective cutting the individuals which are 15-25 cm in base diameter and leaving the stump height more than 30 cm are propitious to forestland recovering in short time. Meanwhile, controlling stump sprouting after two years of cutting and thinning overstocked sprouts have positive influence on sprout growth.

Tree canopy coverage landscape was analyzed based on the design framework of function classification and scale system in the urban region of Guangzhou. The results showed that the ratio of tree canopy coverage was 19.5%, with the highest (26.5%) in Tianhe district, and the lowest (6.6%) in Fangcun district. Ecological beneficial forests were dominant among the five types including ecological benefit forests, public garden, residential forests, production forests and special protective forests. The coverage ratio of ecological beneficial forests was highest and accounted for 55.4% of total tree canopy, and the production forests took second, with 19.9%. The ecological chunk forest had the largest mean acreage, while roadside trees was the smallest. The coverage ratio of extra large patches, with each area larger than 1 hm², was 78.8%, and the ratio of small-sized(<0.1 hm²), medium-sized (0.1-0.5 hm²)and large-sized patches(0.5-1 hm²) was 9.2%, 7.9% and 4.2%, respectively. Extra large-sized patches were dominated in ecological beneficial forests and production forest stands, while other sized patches were regnant in residential forests . Extra large-sized patches were mostly distributed in the mountainous area, which located in the north of the urban region and the eastern developing belt in Tianhe and Huangpu districts, and orchard fields in the south of Haizhu district as well. Number of the planted small-sized patches was the most in the old city area. Most of the large-sized patches were adjacent to the extra large-sized patches, and the pattern might be caused by the fragment of extra large-sized patches in the process of urbanization. Continuous tree canopy is an effective approach for implementing the continuity of ecological progress and pattern. Roadside trees type, being the most at patch numbers and fragmental relatively, has the most potential for forming continuous coverage patch via spatial linkage. The results provided valuable information for related research of urban forest and landscape pattern optimizing at small scale in Guangzhou.

Sap flow meters based on the stem heat balance method were used to continuously measure the sap flow of Phyllostachys edulis in the Forest Ecosystem Research Station in Dagangshan mountain, Jiangxi Province and in the meantime automatic meteorological stations were used to observe the meteorological factors from September, 2009 to July 2010. Results indicated that the average sap flow rate showed distinct diurnal change rhythms both in sunny and cloudy days in different seasons. The fluctuations of the daily sap flow rates were relatively mild from day to day in autumn and winter, while the fluctuations were relatively violent in spring and summer due to the influences by rainfalls. The sap flow usually displayed unmoral curves in fine days, however it sometimes showed bimodal curves in spring and summer, without significant "noontime depression" phenomenon. There was weak sap flow at nights regardless of seasons or weathers, likely driven by root pressure. The main meteorological factors influencing the sap flow varied in different seasons probably because of the different moisture absorption modes in different seasons. The sap flow was most related to air temperature during dormant time and most related to photosynthetic active radiation (PAR) in the growth season. The sap flow showed distinct seasonal dynamics and the rate was (97.88±5.73) g·h^-1, (52.27±3.66) g·h^-1, (167.81±20.15) g·h^-1 and (414.04±48.62) g·h^-1 respectively in the end of growth season, dormant period, early- and mid-phase of the growth season. Multiple linear regression matrix was established between the meteorological factors, regarding PAR, solar radiation, air temperature as independent variables, and sap flow rate of different seasons as dependent variables with high significance.

A cDNA clone encoding HsfA1d was isolated from a cDNA library prepared under heat shock stress in Populus simonii by the RT-PCR method. The cDNA of PsHsfA1d is 2 036 bp in length with an open reading frame (ORF, 1 449 bp in length) which is capable of encoding a protein of 482 amino acids. The deduced protein sequence of the PsHsfA1d shares 86.3％, and 87.4％ identity with functional domain of HSF DBD of Arabidopsis thaliana AtHsfA1d, and Oryza sativa OsHsfA 1 , respectively. Tissue differential expression with realtime-PCR indicated that PsHsfA1d was expressed predominantly in the leaves and roots. We analyzed the expression patterns of PsHsfA1d under abiotic stress conditions and phytohormone treatment, and the result revealed that expression of PsHsfA1d was induced not only by heat-shock, drought and high-salt stress, but also up regulated by GA₃, and ABA, and glucose and sucrose signals. The genomic sequences of PsHsfA1d in 36 individuals were aligned, compared and analyzed using the software MEGA4.0 and DnaSP4.50.7. A total of 207 single nucleotide polymorphisms (SNPs) were detected and the frequency and diversity of SNPs were 1/16 bp and 0.007 72, respectively. In total, 69 SNPs were detected in the coding regions of PsHsfA1d, of which 37, 31 and 1 were silent, missense, and nonsense mutations, respectively; the nonsynonymous nucleotide substitutions (π_nonsyn) was markedly lower than π_syn, with the π_nonsyn/π_syn ratio 0.132＜1, suggesting that diversity at the synonymous sites of exon regions would have resulted from strong purifying selection.

The genetic diversity of eighteen Platycladus orientalis provenances from seventeen provinces was analyzed by AFLP markers.Eight primers produced a total of 1 613 polymorphic bands(92.19%).The average effective number of alleles, Nei's gene diversity and Shannon's information index were 1.199 3, 0.123 9 and 0.194 9,respectively, indicating that there was plentiful genetic diversity among the provenances of P. orientalis. Genetic diversity of the middle provenances was less than that of provenances collected from the south and the north regions. Analysis of molecular variance(AMOVA)showed that variance component within provenances (74.86%)was higher than that among regions(11.12%) and among provenances within regions(14.02%).The distribution of discontinuity, geographical isolation and low levels of gene flow(N_m=1.437 2) between the provenances were major factors that led to genetic differentiation.Nei's (1972) genetic distance was applied to unweighted pair-group method with arithmetic means (UPGMA) cluster analysis,and the results showed that the similar latitude provenances were clustered together, and eighteen provenances were clustered into four groups(north,south,middle and Shandong provenances). A Mantel test confirmed that there was a positive correlation between the genetic distance and geographical distance.

The distribution ratio variation of different forms of calcium in different organs(xylem, phloem, flower and fruit, shoot)of the fruiting basal branch and their relationship to total calcium were studied by sequential extraction procedure during growth and development stage (budding, flowering and fruiting period) in order to provide the basic knowledge of calcium adsorption mechanism of wild Cerasus humilis. The results showed that calcium adsorption and distribution in different tissues and organs weres closely related to the transformation of calcium forms and their distribution. With growth and development of wild C. humilis, the distribution of different forms of calcium in xylem and phloem tended to decrease, while the distribution of different forms of calcium in shoots tended to increase. The peak distribution of water soluble calcium, calcium pectate and calcium phosphate in flowers occurred at peak flowering stage, and the peak distribution of calcium pectate and water soluble calcium in fruits appeared respectively at the initial and the last stage of fruit development. A correlation analysis showed that there was a notably positive correlation between the variation of total calcium distribution ratio in fruits and flowers and the distribution of different forms of calcium in xylem and phloem, but the variation of total calcium distribution ratio in shoots was significantly negatively correlated to the distribution of different forms of calcium in xylem and phloem. It was concluded that the transformation and redistribution of different forms of calcium occurred in different tissues and organs of the fruiting basal branch, and water soluble calcium and calcium pectate were the main forms of calcium adsorption in C. humilis fruits.

Plot survey and stem analysis were conducted in a 10-year-old manchurian ash(Fraxinus mandshurica) plantation with different initial planting density to learn the influence of initial spacing on the biomass accumulation and root growth pattern. 1)single tree biomass increased dramatically with the decrease of initial density(P<0.05), with 30.3%, 85.6% and 146.7% increase for intermediate(I1, I2)and lowest(W)density stands, respectively; in comparison with highest density(N)stand. 2)There were significant differences in stand level biomass among the stands with different initial density, and the total tree biomass production in I1, I2 and W stand was 84.8%, 80.5% and 60.5% , respectively, of that in N stand. The stand level biomass structures were also impacted by initial stand density. 3) The mean single tree root biomass increased with the decrease of initial density, with 34.3%, 83.2% and 139.7% increases in I1, I2 and W stands(P<0.05)in comparison to the N stand, whereas the stand level root biomass production had a drastic decrease with the initial density, accounted for 87.4%, 79.4% and 58.5% of that in the N stand, respectively(P<0.05). 4)The horizontal distribution range of lateral root increased with the decrease of initial density(P<0.05), whereas the taproot rooting depth tended to decrease. In terms of a combination of stand level biomass accumulation, stem biomass ratio and root distribution pattern, we suggest a relatively greater initial planting density for manchurian ash plantation establishment.

In order to find out main factors influencing the feeding of golden monkey(Rhinopithecus roxellana)in Qianjiaping, Shennongjia Nature Reserve, summer and autumn food composition was investigated through quadrat survey and histological analysis of plant remains in feces. The analysis included nutritional components, relative abundance and relative density in the feces. The results showed that, in summer, food composition of Rhinopithecus roxellana was positively correlated to the relative abundance(r=0.656, P=0.000), water content(r=0.078, P=0.609), crude fat content(r=0.020, P=0.896)and the nitrogen-free extract content(r=0.238, P=0.115)of food plants, and negatively correlated to crude protein content(r=-0.113, P=0.459), crude fiber content(r=-0.144, P=0.347)and crude ash content(r=-0.156, P=0.305)of food plants; Food composition in autumn had positive correlation with the relative abundance(r=0.703, P=0.000), water content(r=0.258,P=0.176), crude fat content(r=0.291,P=0.125), crude protein content(r=0.537, P=0.003), crude fiber content (r=0.194, P=0.312)and crude ash content(r=0.308, P=0.104)of food plants, and negative correlation with the nitrogen-free extract content(r=-0.546, P=0.002)of food plants. Principal component analysis suggested that nitrogen-free extract(0.936), crude fiber(0.886)and crude ash(0.870)were the main affecting factors in summer, whereas rude fiber(0.968), crude protein(0.948)and food abundance(0.877)were the main factors in autumn.

AM fungi infection rate, spore density, diversity and distribution in the main plant species at different vegetation restoration stages in Loess Hilly Gully Region were studied. The results showed that 18 AM fungus species, belonging to Gigaspora, Scutellospora and Glomus, were identified from the rhizospheres of the main plant species. Glomus constrictum and Glomus geosporum of Glomus were the common species at different vegetation restoration stages, and they are also the dominant species in the region. Distribution of the other 16 species varied at different stages. There were significant differences in the average infection frequencies of host plants between the first and second stages on sunny slopes. However, the spore density had no significant difference among the five stages. By contrast, there was no significant difference in the infection frequencies among the five stages on shady slopes, and the spore density at the fourth and fifth stages was higher than that at the first and second stages. Richness and diversity of the fungus species were higher at the fourth and fifth stages, and lower at the first and third stages regardless of slope aspect. On sunny slopes, evenness of AM fungi at the second, third and the fourth stages were higher than that at the fifth stage. However there was no significant difference in the evenness on shady slopes. These results are important for further studying the relationships between AM fungi diversity and plant community species diversity in the region, and even greater important for sieving AM applying fungi species with adaptive ability and applying mycorrhizal biotechnology to vegetation restoration in Loess Plateau.

An nsLTPs-like antimicrobial protein gene(LJAMP2)from the seeds of motherwort (Leonurus japonicus)was introduced into Chinese white poplar(Populus tomentosa)via Agrobacterium-mediated transformation using nptII gene conferring kanamycin resistance as a selectable marker. Thirty GUS-positive poplar lines were obtained and stable integration of transgenes in the plant genome was identified by PCR analysis. LJAMP2 expression was detected in transgenic plants by reverse transcription-PCR(RT-PCR). Transgenic poplar lines were tested for resistance to the fungal pathogen Cytospora chrysosperma crude extracts from the transformants showed in vitro inhibitory activity against the fungal pathogen. in vivo assays demonstrated that the transgenic poplar plants displayed a significant reduction in their disease symptoms after infection with C. chrysosperma, compared to the control plants. These results suggested that constitutive expression of the LJAMP2 gene from motherwort could improve resistance to canker disease in Chinese white poplar.

Specific primer pairs were designed according to the gene sequence of cucumber mosaic virus(CMV)and tobacco mosaic virus(TMV)coat protein region. The two viruses could be detected by simple RT-PCR with the primers and the suitable primers were selected for multiplex RT-PCR. Using 18S rRNA of gladiolus as an internal control, a multiplex RT-PCR program was established to simultaneously detect the two viruses of Gladiolus hybridus. Two specific bands,CMV(629 bp)and TMV(423 bp)were amplified from all the samples infected with CMV and TMV by the multiplex RT-PCR. Sequence analysis of the amplified products showed that the nucleotide sequences homology of CMV and TMV was 93%~97% and 99%, respectively, compared with the sequences of other isolates.

Bacillus amyloliquefaciens JK-JS3, isolated from the leaf of the Pinus massoniana in Dr.Sun Yat-sen's mausoleum, is a bacterium and has high nematicidal activity to a nematode(Bursaphelenchus xylophilus). A water solution with the nematicidal activity was isolated and purified from the bacterium culture medium by acid and alkali sedimentation method, and the components was analyzed by gas chromatography and mass spectrum. The result showed that the nematicidal activity components was composed of three compounds which included Hexahydro-5-methyl-1-phenyl-1,3,5-triazine-2-thione, 2,2-dimethyl-N-phenylpropanethioamide and Semiarbazide,4-(1,7,7-trimethylbicyclo hepty1-2-ideno)-.The three compounds have not been reported to have the nematicidal activity before based on a search of information and patents of the three chemical compounds in the SciFinder.

Several Schima superba pure stands and S. superba-Chinese Fir mixed stands afforested during 1968-1997 were selected to study the effect of slope position, slope direction and mix planting with Chinese Fir on growth and wood basic density of S. superba plantation in Jian'ou, Fujian Province. The results revealed a significant effect of slope position and slope direction on the growth and stem form of S. superba, but lower effect on wood basic density. The increment of crown and height was enhanced, and stem form was improved at sunny slope and down-slope, compared with shady slope and mid-slope, whereas DBH increment was higher in shady slope with higher soil water content. When S. superba were mixed with Chinese Fir at appropriate ratio(such as the ratio of 1 :3), stem form and the growth of DBH, height and crown all were improved significantly. The probability of stem forking(SF) of S. superba was fluctuating within 22.50%-35.75%, which mainly was single fork lower than 0.5 m. In pure stands on sunny slope or down-slope and mixed stands(ratio of 1 :3), the probability of stem forking was lower. Moreover, slope position had larger influence on stem fork formation than slope direction. The wood basic density was gradually decreased from pith to bark, was decreased sharply from 15^th to 20^th rings, and reached the minimum during 35^th to 40^th rings. The reduction velocity of wood basic density from pith to bark was increased with the increasing of the diameter increment. The ring width was increased at first and followed by a reduction, with the largest wood formation speed during 5^th to 15^th rings. Accordingly, it was proposed that S. superba plantations should be build on sunny slope and down-slope which had better condition of water, fertility and light. Based on the result, mixed planting at appropriate ratio,enhancing removing buds and shoots of young stand as well as tending and thinning of middle-age stand was proposed to control the stem fork formation, improve the diameter growth and promote plantation productivity in medium-later period and radial homogeneity, and finally obtain the cultivation objective on fast-growing and high-quality craft timber stands.

The synergistic flame-retardant effects of expandable graphite(EG) with ammonium polyphosphate (APP) in wood flour/polypropylene composites were investigated by cone calorimeter (CONE) under a heat flux 50 kW·m^-2. The CONE results showed that both APP and EG decreased the heat release rate (HRR), total heat release(THR), release smoke rate(RSR) and increased the residual char of wood flour/polypropylene system, which indicate APP and EG are effective fire retardants for wood flour/polypropylene composites. However, EG flame retardant displayed the better smoke suppressing performance than that of APP. When the mass ratio of EG and APP was 2 : 1, the incorporation of EG and APP had a positive effect on forming a compact and intumescent char layer with stabilized structure, and showed a good synergistic effect in flame inhibition and smoke suppression. The mechanical test results showed that, even in the presence of maleic anhydride grafted polypropylene copolymer (MAPP), the addition of APP and EG flame retardant also decreased the impact and flexural strength of composites, but EG improved the flexural modulus.

The objective of this paper was to evaluate a micro-tensile testing technique for short length single fiber longitudinal tensile property testing.A newly designed micro tension tester (SF-I) was used to test different cellulosic single fibers, including bamboo, Chinese Fir and ramie. With the new tester, the effect of ambient humidity and the humidity cycle on the tensile properties of the fiber was investigated. The load-deflection curve of single fiber testing showed that a linear behavior presented to failure. The mean value of tensile strength,tensile modulus and strain for the 4-year-old bamboo fiber was 1 710 MPa,27.1 GPa,7.0%,respectively. The bamboo,Chinese Fir and ramie single fiber are all moisture-sensitive. Among the fibers investigated, ramie fiber shows the most sensitive to the humidity. Furthermore, the strain of fibers was smaller and smaller after be repeated tensile under the same load.

The sliced bamboo veneer was treated by fire retardant FRW, and the fire retardancy of the treated and untreated sliced bamboo veneer was tested by cone calorimeter under different retentions. The results showed that: at the heat radiation of 25 kW·m^-2, heat release rate(HRR), total heat release(THR)and total smoke release(TSR)of treated sliced bamboo veneer decreased with the increasing of FRW retention, and it doesn't produce more high flame in burning process, time to ignite(TTI)of treated sliced bamboo veneer was longer, and its residue mass was increased compared with the untreated sliced bamboo veneer; the obvious fire retardation and smoke inhibition effects of the sliced bamboo veneer treated by fire retardant FRW was observed.

Acetic acid lignin(AAL) was isolated from acetic acid pulping waste liquor. The structure of acetic acid lignin was characterized by Fourier infrared spectroscopy(FTIR)and ³¹P-NMR spectrum.And the molecular mass distribution of acetic acid lignin was determined on a gel permeation chromatography (GPC). Rigid polyurethane foams were prepared from acetic acid lignin,polyether polyol and toluene diisocyanate in the presence of catalyst,silicone surfactant and foaming agent. Thermal stability and physical characteristics of AAL-based polyurethane foams were determined by TGA /DSC and compression tests, respectively. And the cell structure of AAL-based PUF was observed by scanning electron microscopy (SEM). The results showed that the acetic acid lignin contained highly reactive hydroxyl groups as reactive chemical reaction sites and can be used to replace part of polyols in the synthesis of polyurethane foams.The polyurethane foam presented better compressive strength.When AAL content was 5%,the compression strength was 1.325 MPa,which was higher 63% than pure PU foams. And the compression modulus reached the maximum, which was 0.181 MPa.The most rapid degradation temperature of AAL-based polyurethane foam decreased with AAL contents increasing.The glass transition temperature had no distinct change .The SEM images suggested that the polyurethane foam containing acetic acid lignin had smooth surface and homogeneous foam structure.

Conductive sheets consisting of copper fibers, UF resin, acrylic resin and surface paper were prepared by hot pressing. The results showed that the electromagnetic shielding effectiveness of conductive sheets increased with rising of filling ratio of the copper fibers .When the filling amount of copper fiber was 250 g·m^-2, the electromagnetic shielding effectiveness of the conductive sheets which consisted of 5 mm long copper fibers were able to reach from 27 to 65 dB, the electromagnetic shielding effectiveness of the conductive sheets which consisted of 10 mm long copper fibers could reach from 31 to 67 dB, and the electromagnetic shielding effectiveness of the conductive sheets which consisted of 15-mm long copper fibers could reach from 31 to 67 dB. All the conductive sheets had good electromagnetic shielding performance. Some other results were found that under the same filling ratio, the longer fiber was, the higher electromagnetic shielding effectiveness could be. Compared with the length of fibers and thickness of sheets, the filling ratio of copper fibers showed the most significant influence on the averages of SE.

Late-season fertilization(LSF), which is developed for preventing nutrient dilution during seedling hardening, is usually performed after the establishment of seedling apical bud. It has been found that late-season nutrient dilution can be alleviated by LSF. Seedling hardening, new root growth, growth, nutrient uptake, and survival after planting could be enhanced by LSF. Also, bud break might be advanced as well. However, most previous reports on LSF focused on fertilizer of nitrogen, whereas the effect of potassium on seedling cold hardiness is inconclusive, and other nutrient elements used as LSF are even much less reported. Usually LSF is applied for quite limited times, or at a constant rate. LSF, with a steady-state nutrient loading has been proven to significantly improve nutrient uptake during hardening.

Surface soil (0-20 cm) samples were collected in 2006 from five moso bamboo (Phyllostachys edulis) plantations which were respectively planted in 2002, 1996, 1990, 1980 and 1960 and extensively managed. Dynamics of the soil microbial biomass and diversity with cultivation time of the bamboo plantations were investigated by means of phospholipid fatty acids (PLFAs) analysis. A site of Pinus massoniana (PM) forest nearby with the similar ecological background was selected as a reference. It was found that the average microbial biomass and diversity were lower (P<0.05) in the soil of the bamboo forest planted in 2002 than in that in the natural PM forest, that is, both species numbers and populations of the soil microbes declined in a short term after PM being transformed into bamboo forest. Afterwards, a gradual recovery tendency of microbial biomass and species was observed with increasing cultivation time of the bamboo plantations, and soil average microbial biomass and diversity in 25- and 45-years-old bamboo plantations (respectively planted in 1980 and 1960) were similar with (P<0.05) that in natural PM forest. Statistical analysis of PLFAs data showed that the composition of soil microbial communities in PM forest was obviously different from those in bamboo plantations, and the dissimilarity increased with time of bamboo cultivation. It was concluded that in comparison with PM, long-term extensive management of bamboo plantations did not bring about significant change in soil microbial biomass and diversity, but microbial communities varied with the increasing time of bamboo plantation, indicting bamboo plantation ecosystem under extensive management could develop rich biodiversity and be sustainably developed.

This study investigated the effect of gibberellin on flower formation of Betula platyphylla and the possible mechanism in the process. In this experiment, different concentrations of GA₃ (50,100,200 mg·L^-1) were sprayed on the leaves of B. platyphylla at the stage of flower induction. The expression of the key genes involved in B. platyphylla flower formation in the apical meristem was studied during the period of flowering differentiation by RT-PCR. The results showed that flowering induction of B. platyphylla was in late May in Harbin and flowering transition was significantly inhibited by different concentrations of GA₃. The expression of flowering-promoted genes, including LFY, GI, ELF3 and LD, were distinct lower than the control group, while expression of the flowering suppressor gene FLC had no significant changes. Therefore, the exogenous GA₃ was of the disincentive during the flowering transition of B. platyphylla. GA₃ plays a negative role in different gene expression of the multiple flowering pathways rather than individual one.

To study the effects of elevated CO₂ concentration()on growth and fruit active components in Lycium barbarum, the seedlings of L. barbarum were exposed to either ambient·mol^-1] or elevated·mol^-1] in open top chambers for four months, and the shoot length, shoot diameter, seedling height, seedling root-collar diameter, and the content of polysaccharide, taurine, flavonoids, carotenoid in the fruits were tested. The result showed that elevated increased the growth rate of seedling root-collar diameter, seedling height, and shoot at early growth stage. The flowering and fruiting date of L. barbarum grown under elevated was earlier than that of the control group, and the content of active components such as flavonoids and carotenoid in the fruits were lower than that of the control group, of which the contents of flavonoids, carotenoid were reduced by 22.1% and 30.8%, respectively, indicating that elevated CO₂ concentration affected the fruit quality of L. barbarum.