[Objective]In this study, we have applied species distribution modeling (SDM) to model the potential distributions of 56 species of wild fruit trees, in order to provide baseline data for effective conservation and management of Xinjiang wild fruit tree resources.[Method] Distribution records of wild fruit trees were obtained from the Herbarium and 13 environmental variables were chosen to define the ecological niche for these sample species. The software package Maxen was employed to model species distributions. After overlapping these 56 distributions, the pattern map of species richness for Xinjiang's wild fruit trees was obtained.[Result]Results showed that wild fruit trees had a wide range of potential distributions in Xinjiang, accounting for 54.5% of the total land area. The species richness was divided into 4 levels:1-4, 5-14, 15-24, and 25-38. However, the areas with high species richness were narrow, and mostly distributed around Ili Valley in western Tianshan Mountains, from Barluk Mountains to Tarbagatai Mountains, and western Altai Mountains. Correlation coefficients between species richness and 13 environmental variables showed that 2 rainfall factors (precipitations respectively of the wettest and the driest seasons), 1 temperature factor (mean diurnal range) and 1 soil factor (carbon density) were closely correlated with the distribution pattern of the wild fruit tree resources (R²>0.35), indicating significant impacts of the four factors on richness and distribution pattern of the wild fruit trees in Xinjiang.[Conclusion] In terms of the level of species richness and species conservation, it is recommended that the Ili Valley in western Tianshan Mountains, the range from Barluk Mountains to Tarbagatai Mountains and the western Altai Mountains should be given priority for conservation.

[Objective]In this study, we investigated the effects of alkali stress on physiological characteristics of Populus alba var. pyramidalis leaves with different maturity, to provide a theoretical basis for indicating the strategy for woody plants to resist alkali stress in arid region.[Method]We chose P.alba var. pyramidalis as the experimental material, and the species is a variant of P.alba and widely distributed in XinJiang area. The young P.alba var. pyramidalis plants were grown in soil pH8.5-9.0 and subjected to 100 mmol·L^-1 Na⁺. The change and distribution of ion content (Na⁺, K⁺, Na⁺/K⁺ ratio, Mg²⁺, Ca²⁺), the response of photosynthetic pigment (Chl a, Chl b, Chl a+Chl b, Car) and the change of antioxidant physiological indices (CAT, SOD, POD, MDA) were investigated in young and old leaves of P.alba var. pyramidalis under alkali stress.[Result]In the control condition, old leaves contained more Na⁺ and less K⁺ than young leaves, and hence a high Na⁺/K⁺ ratio in old leaves; The content of Na⁺ and Na⁺/K⁺ ratio in old leaves increased significantly under alkali stress, but they had no obvious change in young leaves; The content of K⁺ also had no significant change in young and old leaves under alkali stress; On the contrary, Mg²⁺ and Ca²⁺ were mainly accumulated in old leaves in control condition, but the content of them was decreased in old leaves and increased in young leaves under alkali stress. In control condition, the content of photosynthetic pigments (Chl a, Chl b, Car) was much higher in old leaves than in young leaves, but it declined significantly and was lower in old leaves than in young leaves under alkali stress; The content of Chl (Chl a, Chl b, Chl a+Chl b) in young leaves remained unchanged under alkali stress, but the content of Car in young leaves increased significantly under alkali stress. At the same time, the membrane lipid peroxide level (MDA content) in old leaves rose obviously under alkali stress, but it kept at control level in young leaves. The antioxidant enzymes activities (SOD, POD, CAT) in old leaves rose significantly, but they kept at control level in young leaves, except for that the activity of SOD declined.[Conclusion]Under alkali stress, the excessive Na⁺ was mainly accumulated in old leaves of P.alba var. pyramidalis. The ion allocation strategy made old leaves suffer severe oxidative stress and thus protected young leaves that was salt-alkali sensitive from ion injure. Our study indicated that the ion allocation was in favor of young leaves, which was an important strategy for P.alba var. pyramidalis to resist alkali stress and was of great importance for its survival in desert region.

[Objective]The pollution of heavy metals emitted from vehicles can be absorbed by ornamental trees along highway. In this paper, the variation of biological accumulation of heavy metals by ornamental trees with different species at different vertical distance to highway was studied to provide reference for the construction of tree belts with phytoremediation opinion.[Method] Four ornamental tree species of Eucalyptus robusta, Nerium indicum, Ligustrum lucidum, and Cinnamomum camphora were chosen as object of study, and they were grown at 0-5 m and 10-60 m away from the Yong-Tai-Wen highway. The leaves and twigs of trees were sampled for determining contents of Pb, Cd and Cr. The measurement data were analyzed with box-whisker scatter distribution and principal components.[Result] No interactive effects between distance and tree-species were detected on any heavy metal contents. However, contents of Pb and Cr from trees located at 0-5 m away from the highway were higher than those at 10-60 m, with more than 160% higher on average. Heavy metal contents were different among tree species. E. robusta and C. camphora had higher content of Pb in leaves than the other two species (P=0.0007), and twig Pb content in E. robusta was 92% higher than that in L. lucidum (P=0.0004), but the content was 80% lower than that in N. indicum twig (P=0.0371). The accumulated contribution of the first three principle components (PCs) to variation ranged from 71%-75% in terms of the factor of distance, while that ranged from 92%~96% in terms of the factor of species. As for the distance factor, the 1^st PC was characterized by Cd and Cr accumulations in twigs and branches, but the 2^nd and 3^rd PCs were both characterized by Pb accumulation, while the eigenvalue of 3^rd PC was negatively correlated with Cd content (R=-0.954; P=0.046). For the species factor, the 1^st PC was characterized by Pb accumulation in leaves, twigs, and branches, whose eigenvalue was positively correlated with Cr content (R=0.682; P=0.039). The absolute values of eigenvalues for Pb content in E. robusta and C. camphora were higher when composing the analysis between the 1^st and 2^nd PCs, while those for Cr and Pb were evenly distributed with no conclusive data trait.[Conclusion]According to differences between distances away from the highway and the scattered results in tree species comparisons, E. robusta and N. indicum are suggested to be proper for the ornamental tree belt construction along the highways in the study area, for the purpose of potential phytoremediation of heavy metals.

[Objective]Agricultural and forestry residues have many advantages, e.g. accessible, containing a certain amount of nutrients. It is meaningful to reuse them as a matrix of container seedlings to replace non-renewable peat. Our objective is to explore an excellent matrix for the seedlings, by comparing the water and nutrient preservation of nursery matrix composed of agri-forest residues.[Method]These media were composed of waste sticks after edible fungus culture, corn cores or corn straws, with adding larch needle-humus and vermiculite. And then either 1% or 0.5% water retention agent were added to some of the nursery media.[Result]1) The pH, bulk density and total porosity reached the ideal culture substrate requirements in the three agri-forest residues matrices. These indexes had no significant difference from those of peat-soil matrix. 2) Without water retention agent, the water retaining ability of waste fungus matrix and the corn maturity core matrix was almost the same as that of peat-soil matrix. All kinds of matrices with adding 1% water retention agent had significant higher water retaining ability than those with adding 0.5% water retention agent. The water retaining abilities of waste fungus matrix and of corn maturity core with 1% water retention agent adding were all significant higher than that of peat-soil matrix(P<0.05). 3) After adding water retention agent, the overall nitrogen, phosphorus and potassium loss was significantly less than those without water retention agent addition. The more the water retention agent was added, the less nutrient elements lost, reducing by 20%-40%. When added 1% water retention agent, nutrient preserving ability of all kinds of matrices was significantly higher than that of peat-soil matrix(P<0.05), just missing 50%-77% nutrient of peat-soil matrix. 4) Without water retention agent, the seedling height and stem diameter had no significant difference among all the treatments and control. But the ratio of height to stem diameter was significant higher than those in the peat-soil matrix. The seedling quality index was higher in matrix with 1% water retention agent than that in 0.5%, especially the matrix with corn core.[Conclusion]The water and nutrient preservation of nursery matrix composed of agri-forest residues was similar to peat-soil matrix. It is suggested that 1% water retention agent should be added into the agri-forest residues matrices to promote the growth of seedlings.

[Objective] In forest community, the volatile pathway of allelochemical has a significant impact on its natural regeneration. Rhododendron delavayi, R. agastum and R. irroratum are the pioneer and dominant species in Baili Azalea National Forest Park in Guizhou province. Air samples are collected from pure forests of the three Rhododendron communities to analyze their allelochemical components, in order to provide a scientific basis for the natural regeneration of Baili Azalea National Forest Park.[Method] Field investigations of three major Rhododendron communities (R. delavayi, R. agastum and R. irroratum) under natural conditions were conducted using the method of typical sampling plots, Berger-Parker dominance index, Simpson's diversity index, and Pielou evenness index were calculated for each of the sample plots. Based on these parameters, biodiversity of the communities were characterized. Samples of volatile compounds were collected from the three communities using air bags. Components of the allelochemicals in the three communities were investigated and analyzed by using the solid phase microextraction (SPME) technique and the gas chromatography mass spectrometry (GC/MS).[Result] The Berger-Parker dominance index of the three communities from high to low was R. agastum, R. irroratum and R. delavayi, the Simpson index from high to low was R. irroratum, R. agastum and R. delavayi, and the Pielou index from high to low was R. delavayi, R. irroratum and R. agastum. There were respectively 17, 13 and 11 volatile allelopathy components in the air samples of R. irroratum, R. agastum and R. delavayi identified by SPME-GC/MS, and the main volatile allelopathy component was alkanes in all the three communities. Terpenes, organic acids, esters, ketones and phenols were also detected and they are allelochemicals or have inhibitory effects. The components of R. irroratum community were mainly alkanes, terpenes, ketones and phenols, and the highest component was 2,2,4,6,6-pentamethylheptane (30.81%), followed by 5-ethyl-2,2,3-trimethylheptane (19.87%), decane (11.71%), and dodecane (10.00%). The components of R. agastum community were aminly alkanes, terpenes, esters and organic acids, and the highest component was 2,5-dimethylhexane-2,5-dihydroperoxide (20.23%), followed by 5-ethyl-2,2,3-trimethylheptane (18.13%), dodecane (14.30%), and 2,2,7,7-tetramethyloctane (10.20%). The components of R. delavayi were mainly alkanes, phenols, esters and organic acids, and the highest component was decane (22.92%), followed by 2,2,4,6,6-pentamethylheptane (18.11%), γ-butyrolactone (16.82%), and palmitic acid (11.65%).[Conclusion] The three Rhododendron communities had higher dominance and evenness but lower diversity. The hierarchical structure of Rhododendron community was simple. When the canopy density exceeded more than 90%, the process of natural regeneration from seeds of alpine Rhododendron was difficult to complete. Air samples of the three Rhododendron communities were rich in allelochemicals, mainly including hydrocarbons and their derivatives. And the kinds of allelochemicals were positively correlated with community biodiversity. Further studies are required with focus on how the allelochemicals produce impacts in relation with the habitat conditions in the alpine Rhododendron communities.

[Objective] In order to identify and analyze the expression of exogenous genes in transgenic Populus×euramericana cv. '74/76' carrying bivalent insect-resistant genes BtCry1Ac and API (Abbreviation:Transgenic 107 poplar), and to select transgenic 107 poplar lines with high resistance to Lepidoptera pests Hlyphantria cunea and Clostera anachoreta.[Method]Two-year-old field seedlings of ten transgenic 107 poplar lines were selected as materials and non-transgenic 107 poplar as control. Detections of exogenous gene expression were conducted, including PCR detection, absolute fluorescence quantitative PCR, toxin detection and comparative studies on insect resistance of Lepidoptera pests.[Result]PCR detection showed that exogenous genes BtCry1Ac and API existed in the ten transgenic lines, but not in the CK, indicating that BtCry1Ac and API were steadily inserted into transgenic plant genome. The fluorescence quantitative PCR showed transcription abundance of BtCry1Ac in five lines PB1, PB2, PB6, PB9, and PB10 were higher, ranging from 1.72×10⁸ to 7.91×10⁹, PB1 was the highest; and followed by PB3, PB7, and PB8, ranging from 1.03×10⁷ to 2.35×10⁷; PB4, PB5, and CK detected no transcriptional expression of BtCry1Ac. ELISA toxin detection showed the content of Cry1Ac toxin expression was in accordance with variation tendency of transcription abundance. PB1 was the highest, with 665.11 ng·g^-1, PB4, PB5, and CK detected no toxin. The indoor insect feeding test showed that the insecticidal effect of transgenic 107 poplar on H. cunea larvae was higher than that of C. anachoreta. Eight transgenic lines expressed toxin had high resistance to L₁-L₆ (L₁-L₆ represent 1 to 6 instars)H. cunea larvae with a mortality of 100%, but there were differences on lethal time among these lines, the lethal time of PB1 and PB2 on every instars were shorter. PB1, PB2, PB6, PB9 and PB10 had a high resistance to L₁-L₄ C. anachoreta larvae with a mortality of 100%, the lethal time of PB1 and PB2 were shorter. The mortality of PB3, PB7, and PB8 on L₁-L₂C.anachoreta larvae was 100%, but the mortality of L₃-L₄ C. anachoreta larvae was as high as 22.22%. The 8 transgenic lines were divided into two resistance levels:PB1, PB2, PB6, PB9 and PB10 were high resistant lines, which showed high insect resistance to H. cunea and C. anachoreta; PB3, PB7, and PB8 were moderate resistant lines, which showed moderate insect resistance to C. anachoreta, but high resistance to H. cunea.[Conclusion] A series of molecular detections and indoor insect feeding tests were conducted on transgenic 107 poplar in this study. The results indicated that exogenous genes were steadily inserted into the poplar genome, and the 8 lines were of high-efficiency expression. Insect resistance test showed that transgenic 107 poplar had high resistance to H. cunea and C. anachoreta. Five lines were selected and showed high resistance to two pests, the other three lines PB3, PB7, and PB8 showed high resistance to H. cunea, but low or moderate resistance to C. anachoreta.

[Object] Soil animal is a key part and important driving factor of soil ecosystem evolution. The study on the effect of natural factor and human disturbance on the ground dwelling soil fauna community and its niche in Daxing'anling Mountains will help to understand the role of soil biodiversity in the conservation and restoration of swamp ecosystem.[Method] In the late August 2012 and the late August 2013, we investigated the ground dwelling soil animal by pitfall traps at 5 types of swampes, including Larix gmelinii-Ledum palustre-moss swamp (referred larch-palustre), L.gmelinii-Rhododendron dauricum-moss swamp (referred larch-azalea), L.gmelinii-Betula platyphylla-carex swamp (referred larch-birch), and larch-azalea by severe fire disturbance, larch-birch by mild fire disturbance in 2006.[Result] Total of 11079 individuals(16 unknown)were collected from 150 pitfalls, and belonged to 8 Classes, 18 Orders, 3 Suborders and 62 Families, of which 52 groups were macrofauna, and belonged to 6 Classes, 16 Orders. One dominant group was Formicidae, Hymenopetra, accounting for 40.82% of the total number of macrofauna collected, There were 15 micro-meso fuana which belonged to 82 Classes, 2 Orders, 3 Suborders, and among them Neanuridae, Collembola was the dominant group that was 85.03% of the total number of micro-meso fuana collected. In terms of nutrition function, the ground dwelling soil animal was predominant in the phytophagous and the predatory. The result showed that the individual number and groups of the ground dwelling soil animal community were the most in larch-birch, while the least in individual number and group number was in larch-azalea and larch-palustre, respectively. Compared to the same type of undisturbed swamp, the total number of individuals and groups were increased by intermadiate fire disturbance, but the diversity index and evenness index was declined with the fire disturbance intensity enhancement. There were significant differences in the individuals, groups and diversity index of ground dwelling between 2012 and 2013(P=0.05), while the similarity of soil macrofauna was lower than that of micro-meso fauna. The ground dwelling soil animal had significant difference in resource utilization in this study(P<0.01), among which, the larch-azalea had the most common resource utilization, and the least in larch-birch with intermediate fire disturbance, which led to obviously dominance species. After fire disturbance, the similarity became lower in the same type of swamp, and general niche overlap index of the ground dwelling soil animal declined as the available resource declined.[Conclusion]The diversity of ground dwelling soil fauna community was related with the type of marsh. Ground dwelling soil fauna community structure was affected by the environment factor in the study area.

[Objective] In order to develop effective lures that can uniformly and persistently release biologically active semiochemicals in the field, it is necessary to determine the release rates of various insect pheromones and host volatiles from different types of commonly used dispensers after the active compounds are identified.[Method] In this study, the release rates of four common bark beetle aggregation pheromone components (ipsenol, ipsdienol, trans-verbenol and S-cis-verbenol), two major Dendrolimus sex pheromone components (Z5,E7-12:Ald and Z5,E7-12:OH), and two conifer host volatiles (S-(-)-α-pinene and R-(+)-α-pinene) from four different types of dispensers were investigated under laboratory conditions (temperature, 24-26℃; relative humidity, 50%-80%; wind speed, 300 mL·min^-1) using dynamic headspace volatile collection method. The entrapped components on Porapak Q were extracted from sampling tubes with hexane and quantified by Gas Chromatography.[Results] Results indicated that ipsenol had higher release rates than ipsdienol from the polyvinylchloride bubble cap dispensers over the test period, showing significant differences for both (+) and (-) enantiomers of ipsenol and ipsdienol on day 2, 22, and 29. Ipsenol and ipsdienol released quickly in the first two days and gradually declined to the lower release level on day 15, then increased sharply during days 15-36 with a peak of release rates at the day 36, but finally declined to a consistent low release level. The closed polyethylene (PE) tube dispensers (#730) did not release any Dendrolimus sex pheromone components (Z5,E7-12:Ald and Z5,E7-12:OH) while the open PE tubes released them, indicating that these two moth pheromone components can't penetrate the 1 mm thick PE wall. The release rates of these two conifer host volatiles, S-(-)-α-pinene and R-(+)-α-pinene from the PE bottles varied over the whole testing period; with ups and downs during the earlier test period, reached the peak between 2 to 4 weeks after the start, and maintained at low level after the 43^th day. The release rates between these two components on day 15 and 29 were significantly different, even though the differences in their overall average release rates were not significant. Release rates of trans-verbenol and S-cis-verbenol from PE pouch maintained a relatively low level during the first two weeks, then increased sharply to a peak on the day 36 for trans-verbenol or the day 43 for S-cis-verbenol, and then dropped to and maintained at a low level after their corresponding peaks. trans-verbenol showed significantly higher release rates than did S-cis-verbenol throughout the testing period except at the day 43.[Conclusion] Studies of these release patterns of different semiochemicals from different types of dispensers could help us understand the dynamic releasing characteristics of various volatiles in the field, and their potential effects on the semiochemical-based monitoring and control efficacies. Finally, these results would provide some critical information on the selection of optimal dispensers for different semiochemicals in the pest control program.

[Objective] The poplar bacterial canker caused by Lonsdalea quercina subsp. populi is a disease that is a seriously harm to poplar industry. In order to clarify the role of the hrcJ gene playing in the pathogenesis of L. quercina subsp. populi, it's necessary to reveal the function of each gene in type Ⅲ secretion system of the pathogen and provide a theoretical basis for elucidating the pathogenic mechnism of pathogens.[Method]The hrcJ inserted mutant was constructed by homologous recombination. A suicide vector, pEX18Km-hrcJ,that carries hrcJ gene of the pathogen strain N-5-1 was constructed. The suicide vector was introduced into the wild-type strain N-5-1 by using amphiphilic bonding method. The hrcJ gene insertion mutants were screened on LB plates containing the corresponding concentration of kanamycin and rifampicin. Then the hrcJ inserted mutant was verified by PCR and Southern blot. One-year-old seedling of Populus ×euramericana cv.'74/76' were inoculated in an incubator, with strains of the wild-type, the hrcJ gene mutant, and the complemented mutant HBhrcJ respectively, for pathogenecity test.[Result]The PCR amplified fragment sizes are consistent with those expectations and Southern hybridization signal stripe size was the same as expected, showing that the suicide vector pEX18Km-hrcJ has been properly integrated into the target gene. That is the hrcJ gene has achieved insertion mutation due to the homologous exchange. Pathogenicity test on one-year-old poplar branches indicated that the hrcJ gene mutant was significantly less virulent than wild-type, while the complemented mutant HBhrcJ restored the virulence to the wild-type level. Growth analysis showed that growth capacity of hrcJ gene mutant had no significant change compared with that of wild-type, and the ability of biofilm formation evaluated by OD₅₇₀ was similar among strains N-5-1, ΔhrcJ and HBhrcJ. Motility test showed that the motility of hrcJ gene mutant was decreased by 21 percent compared with that of wild-type.[Conclusion] The suicide vector pEX18Km can be successfully used to construct pathogen gene insertion mutation in Lonsdalea quercina subsp. populi, and an alternative method is provided for pathogenic gene research of the pathogen. This result suggests that the hrcJ gene is required for pathogenicity of L. quercina on host plant poplar and hypersensitive reaction on non host plant tobacco. The hrcJ gene mutant of L. quercina did not affect growth of the pathogen and the formation of biofilm, but the obviously decreased motility.

[Objective] Nutshells are important forest biomass resources for energy in China. In order to provide theoretic supports for the thermal conversation and utilization of nutshells,the pyrolysis characteristics of nutshells and the correlations of cellulose,hemicellulose and lignin were investigated in this study.[Method]The cellulose, hemicellulose and lignin contents of seven kinds of nutshells, including Camellia shell, Coconut shell, Tung shell, Walnut shell, Chestnut shell, Pistachio shell and Cashew nut shell, were measured.Using the thermogravimetric analysis the correlations between pyrolysis peak temperature and the cellulose, hemicellulose and lignin content of nutshells were also analyzed.[Result]The major components of the six kinds of nutshell except Cashew nut shell are cellulose, lignin and hemicellulose, and the total content of these three components is more than 73%, while the total content of that in Cashew nut shell is only 47.41%. Several mass loss peaks are observed on temperature range from 200 to 410℃ during the whole pyrolysis process for six kinds of nutshells except Tung shell.Obviously pointed pyrolysis peaks on the left of the maximum pyrolysis peaks are appeared for Coconut shell, Camellia shell, Pistachio shell and Cashew nut shell, while for Walnut shell and Chesnut shell, acromion pyrolysis peaks on the left of the maximum pyrolysis peaks are found. The pyrolysis kinetic equations of all seven kinds of nutshells meet first-order kinetic equation, and the pyrolysis activation energy is ranged in 40-85 kJ·mol^-1. The correlation between the maximum pyrolysis peak temperature and the lignin content of nutshells is significantly positive (R=0.800, P=0.03 < 0.05), the correlation between the maximum pyrolysis peak temperature and the cellulose content of nutshells is weakly positive (R=0.446, P=0.32 > 0.05), and that between the maximum pyrolysis peak temperature and the hemicellulose content of nutshells is weakly positive too (R=0.509, P=0.24 > 0.05), however,the correlation between the maximum pyrolysis peak temperature and the total content of lignin and cellulose in nutshells is more significantly positive (R=0.899,P=0.005 < 0.05). The correlation between the left-side pyrolysis peak temperature and the hemicellulose content of nutshells except Tung shell is significantly positive (R=0.836, P=0.04 < 0.05), and that between the left-side pyrolysis peak temperature and the lignin content of nutshells is weakly positive (R=0.484, P=0.33 > 0.05), and that between the left-side pyrolysis peak temperature and the cellulose content of nutshells is weaker positive (R=0.295, P=0.57 > 0.05).[Conclusion] The pyrolysis characteristics of nutshells is influenced by the contents of cellulose, lignin and hemicellulose.The maximum pyrolysis peak temperature in the DTG curve of nutshells is mainly influenced by the lignin content, while the left-side pyrolysis peak temperature is mainly influenced by the hemicellulose content.

[Objective] Labor is a main production factor of forestry economic growth, this paper attempted to answer the question of what specific impact on the farmer's input and output levels of forestland would be caused by large number of rural labors transferring. The concerns are important significance to enhance the forestland input and output efficiency.[Method] Based on 1178 samples of the survey data in Jiangxi Province, and used quantitative regression mode, this paper analyzed the impacts and its differences on input and output of the farmers forestland by local and nonlocal transfer of labor.[Result]The extent of labor transfer had a significantly negative effect on households' input and output of forestland with an influencing coefficient of -0.099. The effects of labor local transfer on forestland input and output exhibited differently, local transfer had a higher negative effect compared to nonlocal transfer.In particular,there was more obviously negative effect in the areas, which were in the lowest economic development,or in the lowest degree of accessibility,or in the lowest population aggregation.[Conclusion] The research results showed that the transfer of rural surplus labor had substantially completed, the turning point of Lewis has been coming. The advantage of demographic dividend in China has been disappearing. In addition, rural labor local transfer will become a major future trend and direction in a certain stage.It is not good to enhance the efficiency of forest management. Forest management will also face the risks of being extensive once again. Therefore, it is necessary to further improve the forestry cooperative system in order to overcome the shortage of labor supply in the forestry production after the transfer of single-family caused. Meanwhile,it is needed to speed up specialization and scale of the forestry management to ease further exacerbated the trend in concurrent business of farmers' forest management.

Aralia elata is a perennial woody plant which belongs to the Araliaceae. It is distributed widely in the Northeast of China and has great medicinal and edible values. It is also considered as an economic plant. In recent years, understory forest economy represented by growing woody plants as vegetables has become one of the important models of contemporary forestry development. A. elata was given extensive attention because of its high nutritional and pharmacological values. However, its chemical composition and pharmacological activity are still unclear. Meanwhile, serious destruction of A. elata resources due to over harvesting, it is very important to explore high-efficiency reproduction and cultivation techniques. This paper tries to review progresses in reproduction and cultivation techniques, chemical composition and pharmacological activity of A. elata in order to provide a scientific basis for the exploitation and development of A. elata resources. Current status and development trends of A. elata were reviewed in terms of reproduction and cultivation techniques, chemical composition and pharmacological activity. The reproduction model of A. elata can be divided into two types, respectively seed propagation and asexual reproduction. In general, stratification treatment is needed before seed sowing due to the deep dormancy of A. elata. In addition, gibberellins application and high-low changing temperature pregermination can also improve the germination of this species to some extent. Root segment propagation is the main reproduction method of A. elata. Root length had a significant effect on the rooting rate and seedling growth, but root diameter had no significant effect. A. elata seedlings need semi-shade, but mature plants require full sunlight condition. A. elata contains many useful chemical components for human, and many previous studies concerned saponins and polysaccharides. Since the first saponin from root bark of A. elata was isolated, people constantly got new saponin isolated from various organs of A. elata, and also found that the highest saponin content was in the root bark. However, people paid less attention to other chemical components such as volatile oil, vitamins and trace elements, which need further studies. Most studies on pharmacologically active A. elata were focused on the antitumor activity of saponins, and the antitumor mechanisms were also clear, such as inhibited the tumor cell division, proliferation or induced the apoptosis. Different mechanisms also existed among different types of tumors. In addition, the polysaccharides and protein in A. elata plant also had some anti-tumor activity, which needs further research. Future researches should be focused on how to use molecular biology methods to clarify the mechanism of seed dormancy, the synthetic pathways of important active substances and the antitumor mechanism. In addition, metabonomics and fingerprint technologies are also important for evaluation and identification of A. elata resources.

[Objective]As one of the six major estuaries in China, the Hanjiang River Delta (HRD) is of significant importance for conserving wetland biodiversity and guaranteeing ecological safety. Hence, conducting a detailed survey on the mangrove communities and their sites conditions in this area could provide a basis for mangrove conservation and restoration.[Method]The current mangrove communities at the HRD were surveyed by means of route investigation and plot sampling to collect data of communities and site conditions. Multivariate statistical methods were performed for comprehensive evaluation of the communities.[Result]Totally, 13 species of true mangrove and semi-mangrove plants which belonged to 10 families were recorded, including 4 introduced species. Compared with the records in 1964, the species composition was not changed significantly. However, the natural mangrove populations have declined generally, especially characterized by the extinction of natural population of Bruguiera gymnorrhiza. The natural mangroves were retreated, fragmented, and subjected to an area loss of almost three fourths. The flora similarities of mangrove between the HRD and Futian, Zhangjiang Estuary, Jiulongjiang Estuary were higher than those between the HRD and other mangroves of southern China. The species diversity as Shannon-Wiener index (H') ranged 0.168~1.318, and evenness as Pielou evenness index (J) varied between 0.242~0.896. The H' and J indices of artificial mangroves were both higher than those of natural mangroves, indicating a more diversified and well-proportioned state in artificial mangroves. Oppositely, due to the massive dominant population of Aegiceras corniculatum, the natural mangrove communities had lower H' and J indices. The site of Liuhewei had the maximum value of biomass at 106223 kg·hm^-2, which was 14.9 times of the biomass value at the site of Aotou. The environmental factors were statistically significantly different among communities. Salinity and Eh value were significantly correlated, while pH value and other nutrient factors were highly related. The salinity of sediment, salinity of pore water, and Eh of sediment were affected by the sites' locality, which referred to the horizontal distance from estuaries to inlands. Nutrient factors and sediment pH were closely related to each site factor, and their changing trends are related. The results from PCA showed that the site conditions in this area were significantly different among sites. Generally, the sites with lower salinity, higher Eh and higher nutrients values were preferable. Especially for site of Xiangkou, which is bordered in a freshwater dominated intertidal river channel, particularly suited the growth of lower saline preferring species as Sonneratia apetala and S. caseolaris.[Conclusion] It is suggested to perform key conservation of the natural communities at Aotou. Besides, the mangrove at the HRD had limited distribution and population sources. To restore biodiversity rapidly, enforcing the introduction and reintroduction of native semi-mangroves and associates, monitoring the dispersal of introduced mangroves are necessary. Moreover, expanding the area of mangroves through improvement of the existing mangrove plantations was recommended. Based on a comprehensive evaluation of site conditions, the mangroves at the HRD were classified into categories as priority, suitable and unsuitable for development. Restoration of plant communities needs to be implemented according to the local conditions.

[Objective]Citrus Sinensis×Poncirus trifoliata is one of the main citrus rootstocks. Since the species has resistance to citrus tristeza and other good traits, it is used widely in citrus cultivation. This study aims to explore the nitrogen uptake and utilization mechanism of C.sinensis×P.trifoliata further. In addition, it aims to provide scientific basis for improving nitrogen use efficiency and scientific fertilization in citrus production.[Method]C.sinensis×P.trifoliata plants, the experiment material, were grown in hydroponic culture based on Hoagland solution with adjustment in different nitrogen forms. The effect of different ratios of nitrogen forms on the seedling root growth was studied. Besides, the nitrate, and ammonium absorption kinetics characteristics were analyzed in this experiment.[Result]The results showed that the taproot length, the number of lateral roots and root activity were increased first and then decreased as the NH₄⁺ percentage increasing, and mixture of different nitrogen forms promoted taproot length than individual nitrogen forms. A certain ratio of ammonium induced lateral root formation. There was no significant difference in lateral root growth among the treatments of all nitrate, all ammonium and treatment 4(NO₃^-:NH₄⁺=3:7).Treatment 2(NO₃^-:NH₄⁺=7:3) was optimal for root activity, treatment 1(NO₃^-:NH₄⁺=10:0) and 3(NO₃^-:NH₄⁺=5:5), were the second and all ammonium treatment was least. Treatment 2(NO₃^-:NH₄⁺=7:3) was the optimal treatment forroot growth and root activity increasing, and treatment 3(NO₃^-:NH₄⁺=5:5)was the second. As for NO₃^- uptake, the parameter of V_m, K_m and α value were all raised at first time and then reduced as the NH₄⁺ percentage increasing, and the V_m, K_m and α value of treatment 2(NO₃^-:NH₄⁺=7:3) were prominently higher than those of the other treatments. For NH₄⁺ uptake,the parameters of V_m and K_m were all raised at first time and then reduced,but α valuechanged in more complex. The V_m of treatment 2(NO₃^-:NH₄⁺=7:3) was higher than others notably, and the K_m was lower than treatment 3(NO₃^-:NH₄⁺=5:5), but higher than treatment 4(NO₃^-:NH₄⁺=3:7)and all ammonium treatment. However, the α value had no difference from all ammonium treatment, but higher than others.The results indicated that the treatment 2 had a preference and competition for NH₄⁺ and NO₃^-.[Conclusion]The all treatments showed that V_mNO₃^- > V_mNH₄⁺ and K_mNO₃^- > K_mNH₄⁺, indicating that C.sinensis×P.trifoliata would be fond of mixed nitrogen and need more nitrate than ammonium.

[Objective] Quercus serrata var. brevipetiolata as one of the important forest tree species in south China has degenerated due to recent human influences. Study of genetic diversity and genetic structure, as well as correlation between genetic structure and geographical distributions can help to develop sound conservation strategies for Q.serrata var. brevipetiolata.[Method] In this study, a total of 398 individuals of 24Q. serrata var. brevipetiolata natural populations across the species distribution were collected. Eight nuclear microsatellite (nSSR) markers with rich polymorphism were used to analyze the genetic diversity of each population, and genetic differentiation was estimated with analysis of molecular variance (AMOVA). Genetic structure at species level and correlation between genetic structure and geographical elements of Q. serrata var. brevipetiolata were evaluated using STRUCTURE and Alleles In Space programs.[Result] Results indicated rich genetic diversity of the species (H_e =0.43, H_o =0.28, N_a=3.67, N_e=1.96, I =0.66, PPL =82.81%). Analysis of molecular variance (AMOVA) showed that genetic variation mainly existed within populations (F_ST=0.22, P < 0.001), and the genetic diversity differed among different populations. Two groups containing the east and the west populations were plotted based on the Bayesian clustering analysis(STRUCTURE), and gene flow existed among these populations (N_m=1.88). Great genetic differentiation existed between the two groups containing the east and west geographical populations of the species (F_ST=0.25,P < 0.001), while the genetic variations was relatively low among the populations of each group. The Landscape Shape Interpolation analysis (AIS) also suggested great genetic differentiation between the east and west populations, which was consistent with the STRUCTURE cluster results. No correlation was found between the genetic distance and geographical distance (R² =0.011, P =0.07).[Conclusion] The genetic diversity analysis revealed rich genetic diversity of Q. serrata var. brevipetiolata based on the nSSR markers, which was related to its complex population dynamics, anemophilous characteristics and its habitat conditions. Great genetic differentiations exised between the east and west populations, and high differentiations were also found among the west populations. The genetic structure of Q. serrata var. brevipetiolata was probably accounted for the heterogeneity of species habitats (i.e., the western areas with more mountains; the relatively low elevations of east areas with flat terrain; the geographical isolation caused by the smooth topography in the central region) and fragmented environments caused by current human influences. Overall, our study revealed the genetic diversity and genetic structure of Q. serrata var. brevipetiolata, providing a theoretical basis for developing effective conservation strategies for this species.

[Objective] The Zanhuang jujube (Ziziphus jujuba 'Zanhuang')fruit black rot disease is one of the most serious fungal pathogens in China. Bio-control of the disease is of great significance to the fruit green production and its sustained efficacy as well as being free of fungicide pollution. The objective of the present study is to screen out a Streptomyces strain with good inhibitory effect against the fungal disease pathogen (Alternaria tenuissima) and optimize the fermentation medium formula, as well as fermentation conditions with the purpose of laying a foundation for field experiment and the development of bio-control agent.[Method]The agar block method, the Oxford cup method and the medicated plate method were applied in the multiple screening in vitro of 10Streptomyces strains against A. tenuissima, which were originally isolated from special habitats. The optimum fermentation medium and conditions for the selected strain were determined by using a quadratic orthogonal rotation combination design and a single-factor experiment design, respectively.[Result] During in vivo experiment, strains AC03, AC04 and AC07 showed significant antagonistic effect, their diameter of inhibition zone being (32.09±1.45)mm, (15.75±1.34)mm and (18.33±0.78)mm respectively. The fermentation filtrate activity test of the three strains demonstrated that the strains AC03 and AC07 had a diameter of inhibition zone of (20.94±0.92)mm and (23.44±1.63)mm respectively,while the strain AC04 had a diameter of only (14.5±0.71)mm. The further conducted test of the inhibition effect of the fermentation filtrates of the strain AC03 and AC07 on mycelial growth displayed that the antagonistic substance produced by the strain AC07 had a better and longer inhibition effect than that produced by the strain AC03. These tests demonstrated that of the 10 isolates, the strain AC07 had the best inhibition effect on A.tenuissima, that is the main cause of the black rot disease on Zanhuang jujube. The optimum fermentation medium for the strain AC07 consists of maltose, 5.7%; soybean meal, 2.7%; (NH₄)₂SO₄, 0.17%; CaCO₃, 0.22%; NaCl, 0.17% and Yeast Powder, 0.2%. The optimum fermentation conditions were defined as follows:concentration of seed broth, 1.5×10⁷~2.0×10⁸ cfu·mL^-1, inoculation amount, 2% (V/V), the volume of media, 40 mL, in a 250mL flask initial pH at 7.0, fermentation temperature 28℃ and fermentation time 108 h.[Conclusion] The strain AC07 was selected as a new antagonistic Streptomyces for developing biocontrol agent against the Zanhuang jujube fruit black rot disease. The optimization of its fermentation medium and conditions increased the production of the target metabolites, laying a good foundation for further research and development.

[Objective] Taper equation is a key tool to describe stem form variations. By far, different taper equations have been proposed in the world. Among them, the segmented taper equation is one of the most commonly used equation.The method of ordinary least squares regression (OLS) is commonly used to estimate the parameters in the model. However, in practical terms, the application of the segmented taper equation was restricted because the estimated parameters of inflection points a₁ and a₂ (the relative tree height with numerical region of 0 to 1) obtained by OLS regression do not ensure to fall into the region of 0 to 1. Based on the above issue, the aim of this research is to find out the optimal fitting method by using TS(the two-factor automatic selection algorithm)and OLS, which provides technical supports for the construction of tree curve model and fine material.[Method]The three rare species such as Erythrophleum fordii, Castanopsis hystrix and Tectona grandis were developed using 120 individual data (40 for each species), the segmented taper equation was constructed for each species using OLS and TS, respectively. They were evaluated and compared based on the indexes of the coefficient of determination, the residual sum of squares, the mean prediction error, the variance of prediction errors and the root mean square error.[Result]The results show that both the OLS regression and TS fitting accuracy are preferred more than 95% and their coefficient of determination, residual sum of squares are the same. For the variance of prediction errors and the root mean square error TS is the best for E.fordii, C.hystrix and T.grandis; for the mean prediction error OLS method is the best for E.fordii,but TS is the best for C.hystrix and T.grandis, however, the difference between the two methods corresponding the mean prediction error is small; stem profiles prediction results are also very similar; TS can ensure that the inflection point of the estimated parameters is in the (0,1),and it is simple, fitting result is stable.[Conclusion] TS could explained theoretically the optimal value of segmented taper equation parameters a₁ and a₂. Therefore, it was recommended to fit the segmented taper equations with TS.

[Objective]The main purposes of this paper is to analyze the mechanical properties of wood rubber shock absorber for vehicle, to obtain the Johnson-Cook constitutive equation and to check out whether the equation can exactly describe the relationships of stress and strain for wood rubber shock absorber for vehicle.[Method]We select the small Xing'an mountain Korean pine (Pinus koraiensis) wood with the density of 0.439 g·cm^-3 and moisture content of 12%, chloroprene rubber which has good elasticity, high bonding strength, flexible layer, resistant to impact and vibration is also used as experimental materials. Micrometer-level fiber forging machine is applied to process the dried red pine wood into wood fiber, then put these wood fiber into the kneading machine, and obtain the micro wood fiber with width of 1-2 mm, length of 15-30 mm. The specimens of wood rubber shock absorber for vehicle were prepared by several processes including the preparation, weighing, mixing, molding, holding pressure, unloading, and so on. Dynamic compression tests on the specimens of wood rubber shock absorber for vehicle are performed by using Split Hopkinson pressure bar, and get the curves at the strain rate of 1250 s^-1, 1500 s^-1 and 1750 s^-1, respectively. Finally, using the experimental data and Origin software to ascertain the parameters of Johnson-Cook constitutive equation, then the Johnson-Cook constitutive equation, and the experimental curve and the curve fitted by the Johnson-Cook constitutive equation is established and compared, respectively.[Result]The φ10 mm×10 mm specimens of wood rubber shock absorber for vehicle were made, the stress and strain curves at the strain rate of 1250 s^-1, 1500 s^-1 and 1750 s^-1 were obtained by dynamic compression tests, and the Johnson-Cook constitutive equation (σ=[21+0.329(ε)^1.16]×[1+0.148ln(ε·^*)]) of wood rubber shock absorber for vehicle are successfully established.[Conclusion] By analyzing the stress and strain curves of wood rubber shock absorber for vehicle, we can see that the wood rubber shock absorber is sensitive to the strain rate, it can realize a large deformation, the maximums flow stress are higher than 12 MPa under the three strain rates in this study, this is far more than the maximum allowable stress of cellular rubber and neoprene which are widely used as shock absorbing in the present. Furthermore, the toughness and energy absorption properties of wood rubber are also better than chloroprene rubber and cellular rubber. After dynamic compression tests, the specimen of wood rubber shock absorber for vehicle showed 45°splitting damage on surface when the strain rate is 1500 s^-1, and the destruction is mainly occurred on gum. The fitting degree of the experimental curve and the curve fitted by the Johnson-Cook constitutive equation is good when the strain is smaller, especially at the strain rate of 1250 s^-1 and a strain of less than 0.056, the fitted value is almost completely coincide with the experimental value.

The 'Jinming 1' is a new clonal tea cultivar derived from local population by the systematic selection. It has many excellent traits, such as medium sprouting, high yield, elite quality and strang resistance. Its leaves are suitable for manufacturing of green tea. The baked green tea appears tender green bloom and tippy shape, bright green liquor color, clean aroma lasting, mellow taste, and bright green infused leaf. The cultivar is suitable to be cultivated in Hubei Province and the area with similar climate.