【Objective】Population structure and dynamics of plant can reflect the survival of the population and display the interaction between plant and environment. It is an important content of population ecology, and it has significant implications to protection and utilization of plant resources. Juniperus rigida is a wild tree species with priority for protection in Loess Plateau, a comparative study on structure and dynamics of Juniperus rigida populations in different regions of Loess Plateau was carried out to analyze population survival and dynamics of Juniperus rigida in Loess Plateau, in order to reveal the trend of population development. This study would have important theoretical and practical significance for developing strategies of rehabilitating Juniperus rigida population.【Method】A field survey was carried out on 5 populations of Juniperus rigida selected in 5 different regions in Loess Plateau (Wuchuan, Inner Mongolia; Zhuolu, Hebei; Hunyuan, Shanxi; Fugu, Shaanxi; Helanshan, Ningxia) by using sample plots. According to the characteristics of life history of the species and considering results from previous studies, diameter, height and crown width were divided into classes and population structure was constructed using the classes. Static life table, survival curve, mortality curve, disappearance rate curve were produced using space to replace time, i.e. diameter structure instead of age structure. 4 functions (survival, accumulative mortality, mortality density, and hazard rate) of survival analysis were used to analyze population dynamics of Juniperus rigida.【Result】 Different extents of absence of some diameter classes was found in diameter structure of 5 populations; Height structures of Zhuolu and Hunyuan populations were relatively complete; Certain extent of absence of crown-width classes were found in the 5 populations, the crown coverage of Wuchuan, Zhuolu and Hunyuan populations were mostly within 2 m², while Helanshan population was mostly larger than 3 m². The static life table showed that there were large differences of number of survival trees among different age classes, the number of survival trees decreases with age; the highest rate of mortality and disappearance rate were both in age class IV; and the highest life expectancy was in age class I. Two types of the survival curves of 5 populations were found, Wuchuan fitted Deevey-III while the others tended fit Deevey-II. The changes of mortality and disappearance rate were in similar trends for the 5 populations. Four survival curves of 5 populations showed that, the populations Wuchuan and Fugu reduced at young ages, grew stably at middle ages and declined at old ages, and Fugu showed a sharper reduction, while the populations Zhuolu and Hunyuan had a steep reduction in early growth and a late recession, and the population Helanshan reduced slightly at young ages and recessed late.【Conclusion】There were some differences among 5 populations of different regions in the structures of diameter class, height class and crown width class. Populations of Zhuolu and Hunyuan showed regeneration potential as the population density of them were relatively large and they also had a certain number of young plants; Fugu population had a considerable number of aging plant; the diameter class structures of Fugu, Wuchuan and Helanshan were relatively complete, while the population density were smaller and young plants were comparatively rare. There were environmental screenings and competitive pressures in the process of young trees growing up into big trees, and the survival ability of the big trees were stronger. The populations Zhuolu and Hunyuan could be restored and updated if the ecological environment could be improved as there were some young trees in Zhuolu and Hunyuan populations; the regeneration and development of Fugu population lacking young trees would be limited without the supplementation of young trees. In order to protect the populations of Juniperus rigida, attentions should be paid to protecting the young trees; and measures should be taken to promote germination as it was low under natural conditions; For populations with serious aging such as Fugu population, supplementary plantings should be used to ensure regeneration and development of the populations.

【Objective】Xanthoceras sorbifolia is naturally distributed in the northwest of China, strongly tolerant to cold, drought and poor site conditions. It is an important species for oil production and erosion control in north China. Moreover, it is an ideal tree species for land conversion of cropland to forest and for management of barren hills in the northern Loess Plateau of China.【Method】In order to understand the characteristics of seed germination, seedling development and their influencing factors, 24 sampling plots were established in 3 habitats (sunny slope, semi-sunny slope and semi-shady slope) of X. sorbifolia forests on the Loess Plateau where is the central distribution of the species. 【Result】One-year-old seedlings were found at all habitats, but the average number varied among habitats. A larger number of 632 individual·hm^-2 at the sunny slope, 48 individual·hm^-2 at the semi-shady slope. The conversion rates of seeds to seedlings were low at all 3 habitats, and manifested as semi-shady slope (0.57%) > semi-sunny slope (0.43%) > sunny slope (0.25%). The total number of seedlings was small at all 3 habitats, and gradually decreasing with the age of seedlings. For different ages from 1-5 years, the number of seedlings showed the following order: sunny slope > semi-sunny slope > semi-shady slope. Due to the differences of sunlight intensity and moisture content among the 3 habitats, X. sorbifolia seedlings has evolved different adaptive strategies, the height, basal diameter, and crown width of 1-5 year seedlings showed the order of sunny slope > semi-sunny slope > semi-shady slope. The sunny slope was more beneficial to the growth of X. sorbifolia seedlings. The underground biomass of 1-5 year seedlings were greater than above-ground biomass at all 3 habitats, and above-ground biomass and underground biomass showed the order of sunny slope > semi-sunny slope > semi-shady slope. Due to environmental heterogeneity, the age of maximum biomass ratio of underground to aboveground (R:S) differed among the 3 habitats, at sunny and semi-shady slopes the R:S value peaked at the age of 2 years, whereas t the semi-sunny slope, the value peaked at the age of 4 years. The stem dry mass, leaf dry mass, and root dry mass of 1-5 years seedlings were greater at the sunny slope than the semi-sunny and semi-shady slopes, and the difference tendency to increase with age. With the increase of age, the biomass ratios of stem, leaf and root at sunny slope respectively to those at semi-sunny and semi-shady slopes will be increasingly different. Environment factors had significant influence on the number, height, and biomass of seedlings. The number of seedlings was significantly positively correlated with light intensity, and significantly negatively correlated with the total plant coverage. The height of seedlings was significantly negatively correlated with soil moisture. The biomass of seedlings was significantly positively correlated with light intensity.【Conclusion】 At the sunny slope, seed germination rate was lower. However, it was beneficial for establishment of the seedlings compared to the semi-sunny and semi-shady slopes. The growth performance of seedlings was superior at the sunny slope to at the semi-sunny and semi-shady slopes, indicating that at this habitat the seedlings could make full use of growing conditions to shorten the time for entering the main forest storey. Therefore, the sunny slope should be selected for growing plantations of Xanthoceras sorbifolia.

【Objective】The study was intended to understand population structure and spatial patterns of 5 species of Syzygium in tropical evergreen monsoon elfin forest of Tongguling Natural Reserve, Hainan Wenchang.【Method】A 2.56 hm² permanent sample plot was established in tropical evergreen monsoon elfin forest. Common methods for population structure and spatial patterns were used: analysis of population structure of diameter-class, static life table, survival curve, function Ripley's K that was part of spatial point pattern analysis and SPSS software were applied in the study. Spatial pattern, inter-specific association, and relationships of aggregation scale and dominance of five typical Syzygium plant species were studied by using function Ripley's K and software SPSS. 【Result】Mortality of population increased along with the increase of age-class, but the life expectancy was opposite to this trend.. Evident fluctuations of the value of life expectancy were found among three species Syzygium tephrodes, S. buxifolium and S. acuminatissimum, this phenomenon indicated that density regulation process might have existed in the three species, so that density of populations could achieve the best growing condition for individual trees. The largest number of trees were found in S. tephrodes (1 950 trees), and most of them were seedlings and young trees, indicating good regeneration of the population. Survival curve tended to gradually close to the model Deevey II with increase of the age-class, indicating a stable mortality was maintained and regeneration allowing the population continue to survive. The total number of individual trees did not significantly differ among the other 4 species (374 trees of S. buxifolioideum, 390 trees of S. buxifolium, 393 trees of S. championii, and 282 trees of S. acuminatissimum). Although their survival curve tended to close to the model Deevey I, there were yet some differences among these species. For example, there were fewer seedlings and young trees (82 trees) in the population of S. buxifolioideum. Although the regenerated seedlings can grow up and survive for the physiological life span (Model Deevey II), too few trees may influence normal reproduction of the population. The other 3 species had certain quantity of seedlings and young trees, although their regeneration ability was inferior to S. tephrodes, they still had a great potential for survival in the community. Generally, the spatial distribution of the 5 species followed a normal pattern, clustering in small scale and random to uniform distribution in larger scale. But regular distribution appeared on certain scope of scales in population of S. buxifolioideum, S. championii, and S. acuminatissimum, indicating competition from other populations on these scales. The aggregation scale and scope of the 5 species decreased with the decline of their dominance. Thereinto, there was a significant linear correlation between aggregation scale and dominance of population. The regression equation was y = 58.531x－132.33 (R² = 0.958,P = 0.004 < 0.01). Negative correlation was found between S. acuminatissimum and S. buxifolioideum or S. acuminatissimum and S. buxifolium, in addition, other 4 populations could coexist on any scale. 【Conclusion】Syzygium plants was growing well in tropical evergreen monsoon elfin forest. They all have a certain ability of regeneration. Significantly, there were fewer seedlings in the population of S. buxifolioideum than other species, and pressure of competition from the other populations (S. acuminatissimum) appeared on a larger scale. Therefore, a greater attention is needed in management of secondary natural forest.

【Objective】Forest biomass is a basic quantity character of the forest ecological system. Biomass data are the foundation of researching many forestry and ecology problems. Therefore, accurate quantification of biomass is critical for calculating carbon storage, as well as for studying climate change, forest health, forest productivity and nutrient cycling, etc. Directly measuring the actual weight of each component (i.e., stem, branch, foliage and root) is undoubtedly the most accurate method, but it is destructive, time consuming, and costly. Thus, developing biomass models is regarded as a better approach to estimating forest biomass. However, some issues are needed to take care when constructing and applying biomass models, such as: 1) some reported biomass models may not hold the additivity or compatibility among tree component models; 2) which model error structure is appropriate for biomass data, i.e., additive error structure versus multiplicative error structure; 3) few models are available for tree belowground (root) biomass. Researchers have been continuously working and debating on these issues over the last decades. Development of the additive system of biomass equations were reported in the literature. However, how to evaluate the model error structure of the biomass equation in forestry have not been well investigated so far. The present paper mainly deals with two parts: evaluating error structure of the biomass model and developing the additive system of biomass equations.【Method】The P. simonii×P. nigra plantation in the west of Heilongjiang Province of China is selected to ensure error structure by likelihood analysis. Nonlinear seemly unrelated regression (NSUR) of SAS/ETS module is used to estimate the parameters in the additive system of biomass equations. The biomass model validation is accomplished by Jackknifing technique.【Result】The multiplicative error structure was favored for the total and component biomass equations for P. simonii×P. nigra plantation by a likelihood analysis, and the additive system of log-transformed biomass equations should be applied. Overall, the R_a² of all biomass models was between 0.92 and 0.99. The mean relative error and mean absolute relative error were smaller for most biomass models. All models for total and component biomass had the good prediction precision (85 % or more). The effect of total tree, aboveground and stem biomass models are better than root, branch, foliage and crown biomass models. Overall, all models for total and component biomass could be a good predict of the P. simonii×P. nigra biomass.【Conclusion】Although the significance of likelihood analysis is proposed by several studies, it has not been widely applied in forestry. When total biomass is divided into aboveground and belowground biomass, aboveround biomass is divided into stem and crown biomass, crown biomass is divided into branch and foliage biomass, and stem biomass is divided into bark and wood biomass, the additivity of total and component biomass should be taken into account. Overall, the error structure and additivity of biomass models are the two key issues, and should be taken into account when biomass models are constructed. If the two issues are well solved, the constructed biomass models will be more effective.

【Objective】In this study, we investigated effects of drought stress on morphology and physiology characteristics of Artemisia ordosica and compare with the drought-resistant ability of three different provenances of A. ordosica, to provide a theoretical basis for the introduction of the species to China's arid and semi-arid area.【Method】Three different provenances of A. ordosica were collected from Mu Us Sandy land, Kubuqi desert, and Desert-steppe transitional zone, and subjected to different soil moisture to investigate the changes of plant height, stem size, leaf area, Sla, content of Chla, Chlb, Chl(a+b) and Car, Chla/b and Car/Chl and content of starch, soluble sugars and NSC.【Result】The response of morphology characteristics, photosynthetic pigment content, and contents of starch, soluble sugars and NSC of three different provenances of A. ordosica to drought stress was consistent. Namely, as the drought stress increased, 1)plant height, stem diameter, leaf area and SLA, showed a trend of gradual decrease. The plant height, stem size, and leaf area of A. ordosica from Kubuqi desert were greater than those from Mu Us Sandy land and Desert-steppe transitional zone under the severe drought stress. However Sla of the provenance from Kubuqi desert was less than that from Mu Us Sandy land and Desert-steppe transitional zone.2)Chla,Chlb,Chl(a+b),and Car contents、Chla/b and Car/Chl of A. ordosica leaves showed a trend of first increase and then decrease under drought stress. Contents of Chla,Chlb,Chl(a+b) of A. ordosica leaves from Kubuqi desert were higher than A. ordosica from Mu Us Sandy land and Desert-steppe transitional zone under the severe drought stress. However there were no significant differences in contents of Car and Car/Chl of the three different provenances. The Chla/b of A. ordosica from Desert-steppe transitional zone was greatest, followed by that from Mu Us Sandy land, and then by that from Kubuqi desert.3)Contents of starch, soluble sugars and NSC of three different provenances leaves showed a trend of first decrease and then increase. Contents of starch, soluble sugars and NSC of A. ordosica from Desert-steppe transitional zone were higher than A. ordosica from Kubuqi desert and Mu Us Sandy land under severe drought stress, and contents of starch, soluble sugars and NSC of A. ordosica from Kubuqi desert were higher than those of A. ordosica from Mu Us Sandy land. Contents of starch, soluble sugars and NSC of A. ordosica from Kubuqi desert were higher than those of A. ordosica from Mu Us Sandy land and Desert-steppe transitional zone under slight drought stress.【Conclusion】Through the comparison of morphology and physiology characteristics of three different provenances of A. ordosica, we find that the drought resistance of A. ordosica from Kubuqi desert is stronger than A. ordosica from Mu Us Sandy land and Desert-steppe transitional zone.

【Objective】 To elucidate photosynthetic characteristics and the relationships with leaf nitrogen content and nitrogen allocation in leaves of Torreya grandis at different position and different leaf age, the light response curve, CO₂ response curve, specific leaf weight (SLW), chlorophyll content of apical shoot (A) and side branches (S) leaves at different leaf age were studied. This study aims at providing a theoretical basis for the further development of the high yield cultivation. 【Method】 We measured the light response curve, CO₂ response curve, chlorophyll content, leaf nitrogen content of the current year leaf, one-year-old leaf, two-year-old leaf of different position under natural conditions. 【Result】 The results showed that LSP (light saturation point) and P_max (maximum net photosynthetic rate) decreased with increasing leaf age. We also found that chlorophyll content, leaf nitrogen content per dry weight, the fraction of leaf nitrogen allocated to carboxylation (N_C), the fraction of leaf nitrogen allocated to bioenergetics (N_B), photosynthetic nitrogen utilization efficiency (PNUE) decreased while SLW increased with increasing leaf age. Moreover, a significant negative correlation was observed between PNUE and SLW. However, there were no differences in P_max, Chl content, N_M, N_C, N_B, N_L, PNUE and SLW between the apical shoot and the side branch at the same leaf age. 【Conclusion】 The result indicated that the net photosynthesis rate had distinct differences with the increasing leaf age, which would be mainly due to the differences in Chl, V_cmax, J_max. Compared with the current-year leaves, the relatively older leaves invested more nitrogen to cell walls relative to photosynthetic structure, correlating with leaf toughness, with less nitrogen allocating to N_C, N_B, N_L, causing a decrease in photosynthetic rate and PNUE. There were no differences in photosynthetic characteristics between the apical shoot and the side branch at the same leaf age. This study clarifies the reason for the different photosynthetic characteristics and their relationships with leaf nitrogen content and nitrogen allocation in leaves of different position at different leaf age, which is vital for increasing the fruit production of T. grandis by adjusting material investment, distribution pattern and improving photosynthetic performance.

【Objective】 In this study, the damage effect of 5 kinds of phenolic acids with actual concentration in continuous cropping soil on Malus hupehensis. seedlings was investigated to provide the theory basis for prevention and control of apple replant disease. 【Method】 To understand the phytotoxic mechanisms induced by phenolic acids involved in this phenomenon, M. hupehensis seedlings were planted in sand and treated with five phenolic acids (phloridzin, phloretin, cinnamic acid, p-hydroxybenzoic acid, phloroglucinol) at the respective original concentration in the orchard soils. The effects of phenolic acids on the photosynthetic rate and antioxidant systems of M. hupehensis seedlings were analyzed. 【Result】 The plant growth, photosynthetic parameters (P_n, G_s, T_r), chlorophyll contents, activities of superoxidase (SOD), catalase (CAT) and peroxidase (POD), and content of malondialdehyde (MDA), proline, and soluble protein were measured. The results showed that all five kinds of phenolic acids in a continuous cropping orchard all inhibited the growth of M. hupehensis seedlings, and reduced the photosynthetic rate and pigment contents in the leaves. At the same time, the activities of SOD, POD and CAT declined, while the proline, soluble protein, malondialdehyde contents increased under the phenolic acids stress. Among the 5 kinds of phenolic acids, the phlorizin treatment obviously reduced the fresh and dry weight, to 72.2% and 61.4% of the control, respectively. Phloroglucinol had the least impact on the fresh and dry weight, only reduced to 92.6% and 96.3%, respectively. Compared to the control, phlorizin distinctly reduced the P_n, T_r, chlorophyll contents, the activities of SOD, POD and CAT, by 66.9%, 53.2%, 57.1%, 42.7%, 60.2% and 81.5%, respectively;Phloroglucinol reduced the P_n, chlorophyll contents, the activities of SOD, POD and CAT by 34.7%,13.0%,13.0%,4.3% and 24.0%, respectively. The content of MDA in leaves varied significantly among the 5 kinds of phenolic acids treatments, with the order of phloridzin > phloretin > p-hydroxybenzoic acid > cinnamic acid > phloroglucinol > control. The contents of proline and soluble protein were also obviously increased with phenolic acids treatments. Phloridzin treatment led to the highest increase in contents of proline and soluble protein, to 5.98-fold and 3.03-fold of the control, respectively. The phloroglucinol treatment made the contents of proline and soluble protein increased by only 3.38-fold and 1.63-fold of the control, respectively. 【Conclusion】 This experiment showed that the toxic effect on the M. hupehensis seedlings varied significantly among the 5 kinds of phenolic acids. Phloridzin had the most damage to the photosynthetic rate, chlorophyll contents and the antioxidant system of seedlings, therefore, measures should be taken to degrade phloridzin and prevent its concentration from excessive high to inhibit the growth and development of M. hupehensis seedlings.

【Objective】 To investigate difference in the growth behavior of pollen tube in the pistil of Camellia oleifera after self- and out-cross pollination and to identify the types and characteristics of self-incompatibility of the plant. Further to enrich and complement the current understanding of C. oleifera in reproductive biology and also to provide a theoretical basis for increasing oil production. 【Method】 The structural characteristics of C. oleifera and the growth process of pollen tube in the pistil were observed using fluorescence microscopy combined with the modified fluorescent pallet method, fluorescence sectioning, and the routine paraffin method, according to the experimental principles of observation of the pollen tube under a fluorescence microscope as well as the characteristics of the pistil of C. oleifera. The incompatibility responses of the self-crossed pollen tube were observed using scanning electron microscopy to characterize the anatomic properties of the self-incompatibility of C. oleifera. 【Result】 The growth of the pollen tubes was observed via the stylar canal, comprised of a layer of specialized canal cells. The styles were open type and connected at the stylar base and formed a hollow placenta. After pollination, no significant difference was observed in the pollen tubes of the self-crossed and out-crossed stigma and medial styles. Pollen tubes of both styles reached the stylar base; however, a majority of the self-crossed pollen tubes grew slowly and resulted in an incompatible callose reaction as they failed to enter the locule. The magnified part of the self-pollinated pollen tubes revealed intumescence, bifurcation, coiling, folding, and wave lines that resulted from partially increased thickness of the pollen tube walls. The incompatible callose reaction was accompanied by gradual closing of the stylar canal, whereas the out-crossed pollen tubes successfully entered the locule with subsequent entry into the embryo sac at a 90° angle at the ovule micropyle position. 【Conclusion】 Based on the anatomical characteristics, we ascertained that C. oleifera was a self-incompatible plant and belonged to the prezygotic self-incompatibility type, which occurred between the stylar base and upper ovary. Future studies will be directed to understanding of the physiological and molecular mechanisms that restrict the growth of the self-crossed pollen tubes of C. oleifera. In view of the differences in fruit-setting rates among different varieties, focus will also be placed on the mechanisms behind the difference in the intensity of self-incompatibility of different varieties. Furthermore, self-incompatibility of C. oleifera occurs at the hollow stylar base where the stylar canals close intensely, which is close to the ovary, rather than in the style with a relatively loose interspace of the stylar canal. Whether this phenomenon is universal among the self-incompatible plants with hollow styles or the self-incompatible plants of the genus Camellia remains to be explored.

【Objective】 Genus Populus, with many species and a long history of cultivation and utilization, is widely used for afforestation, shelterbelt and timber production. In recent decades, with rapid progress in Populus breeding in China, a large number of new varieties with fast growth and superior characteristics have been developed. However, the genetic basis of these new varieties were narrow and genetic differences among parental trees for hybridization was small, and morphological differences among Populus varieties is becoming increasingly smaller, leading to difficulties in variety identification and protection of plant breeders' rights (PBR). How to distinguish accurately and quickly new Populus varieties has become the top priority. This study was aimed to construct fingerprints, identify pedigree relationships, analyze genetic diversity and detect ploidy of 24 accessions of Populus germplasms. 【Method】 Fingerprint construction and pedigree relationships of 24 accessions of Populus germplasms were analyzed using TP-M13-SSR (simple sequence repeat with tailed primer M13). 200 pairs of SSR primers were selected from Populus SSR database and screened by 4 accessions of genetically distant Populus germplasms. 19 pairs of primers with clear amplification bands, high polymorphism and stable repeatability were selected and used for PRC amplification of the 24 accessions of germplasms. PCR products labeled fluorescent were detected by using GeXP capillary electrophoresis. UPGMA (unweighted pair group method arithmetic averages) were used for clustering analysis. FCM (flow cytometry) was used to detect the ploidy. 【Result】102 fragments were generated from 19 pairs of SSR primers, including 97 polymorphic fragments, accounting for 95.10% of the total. The number of alleles at each locus was between 2 and 11, with an average of 5.37 alleles for each pair of primers. No differences were detected among varieties P. deltoides ‘2025', ‘Zhonghong' and ‘Quanhong' by the 19 pairs of SSR primers. These 3 accessions of Populus germplasms had a unique fingerprint pattern relative to other 21 accessions of germplasms. The rest 21 accessions of Populus germplasms could be completely distinguished by 3 efficient pairs of SSR primers, ORPM_103, ORPM_180 and GCPM_1255. The fingerprints constructed by SSR markers were basically in consistence with the pedigree relationships. Cluster analysis by NTSYS-pc 2.10e software showed that the similarity coefficient ranged from 0.50 to 1.00. When the similarity coefficient was 0.56, 24 accessions of Populus germplasms were divided into five categories: the first category included P. deltoides ‘55/56’, ‘Zhonghuai 1’, ‘Zhonghuai 2’, I-69, ‘Imperial’, ‘2025’, ‘Zhonghong’ and ‘Quanhong’; the second category included P. cathayana, ‘Senhai 1’ and ‘Senhai 2’; the third category included ‘2KEN8’, ‘Danhong’, ‘Nan’, ‘239’, ‘1-116’, ‘Zhongcheng 1’, ‘Zhongcheng 2’, ‘Zhongcheng 3’, ‘Zhongcheng 4’ and ‘Zhongyu 1’; the fourth category included ‘Beikang’ and ‘Chuangxin’; the fifth category included ‘Zhonglin 46’. Loci with 3 different alleles were amplified in ‘Zhonghuai 1’, ‘Senhai 1’, ‘Senhai 2’, P. cathayana and ‘Zhonglin 46’, while loci with only 1 or 2 alleles were amplified in the rest 19 accessions of Populus germplasms. The result of FCM confirmed that these 5 accessions of germplasms were triploid, consistent with the result of SSR detection. 【Conclusion】 In this study, fingerprint construction, genetic diversity and FCM analysis were carried out for 24 accessions of Populus germplasms. SSR markers could effectively detect pedigree relationships between parents and offspring, and accurately reflect the ploidy of plants. 3 pairs of SSR primers were found to be able to identify 21 accessions of Populus germplasms. 5 accessions of Populus germplasms were found triploid. The results provided a theoretical basis for variety identification and protection of plant breeder's rights for Populus.

【Objective】 A gene, EgrDREB2A , was isolated from the mRNA suppression subtractive hybridization library of Eucalyptus grandis (Eucgr. G03094). Based on the analysis of structure, subcellular localization of EgrDREB2A protein and gene expression under different treatments of low temperature, ABA and salt, the roles of EgrDREB2A in the resistance to abiotic stresses of Eucalyptus grandis were discussed. 【Method】 SMART and MatInspector softwares were used to analyze the protein structure of EgrDREB2A and the cis-elements in promoter sequence of the gene. Phylogenetic tree of DREB proteins was constructed by MEGA software. Subcellular localization of EgrDREB2A was characterized with the method of introducing EgrDREB2A-GFP fused genes into onion epidermal cells via gene gun bombardment. And, gene expression analysis in different tissue, under treatments of low temperature, ABA, salt and circadian rhythm were carried out by semi-quantitative and quantitative RT-PCR method respectively. For the gene co-expression of EgrDREB2A under different time treatment at 4 ℃, WGCNA and Cytoscape softwares were used. 【Result】 EgrDREB2A was classed into DREB2 group because the protein it encodes containing one AP2 domain which including a YRG and a RAYD conserved regions. The phylogenetic tree based on homology comparison showed it belonging to subtypeⅠof DREB2 group. Several cis-elements related with plant stress response were found in the EgrDREB2A promoter sequence. Nuclear localization with DREB2 merged protein with GFP implied EgrDREB2A mainly located in the nucleus. qRT-PCR result of EgrDREB2A under 0 ℃, 2 ℃,4 ℃, 6 ℃ and 8 ℃ revealed it was induced. Time course (0.5, 2, 6, 12, 24, 48 h) treatments to E. grandis seedlings at 4 ℃ also increased its expression as the time delayed. The genes co-expressed with EgrDREB2A under different time treatment at 4 ℃ were mostly associated with plant response to abiotic stresses. EgrDREB2A expression increased at the first and then decreased under 100 μmol·L^-1 ABA treatment. However, under the salt stress (200 mmol·L^-1), it was inhibited firstly and then induced. Circadian rhythm also regulates the EgrDREB2A expression, and the transcription level of it was promoted under light and hampered in the darkness. 【Conclusion】 EgrDREB2A is a transcriptional factor which was classified into DREB2 group. The expression of it was induced by low temperature and ABA, salt treatments and circadian rhythm also changed its transcription level. Most of cis-elements found in the promoter of EgrDREB2A and genes co-expressed with it were all associated with plant stress response. All these results showed EgrDREB2A possibly played an important role in the process of resistance to aboitic stresses in E. grandis.

【Objective】The remote sensing technology was used to monitor the vegetation restoration after fire, providing a scientific base for carrying out restoration measures in burned areas. The normalized difference vegetation index (NDVI) is an important index to reflect the growth condition and distribution of vegetation. It has been proved in previous studies that this index has a significant correlation with vegetation coverage. Thus the increasing biomass and the vegetation coverage in burned areas can be monitored through the satellite remote sensing images.【Method】 The Songling burned area, which was burned in spring of 2006, in Daxing'anling was selected as a case study. A series of NDVI data before and after the fire, which were extracted from the MODIS data, and the field investigation data were used to analyze the relationships between vegetation characteristics after fire, burned severity and vegetation types. Data of NDVI in the burned area were extracted before and just after the fire, and the fire severity was classified using the supervised classification method. The maximum NDVI in the same date of August in 2003-2005 was used as the contrast to analyze the vegetation index changes on the time series. 【Result】Low, moderate and high burning severities were accounted for 28.93%, 40.1% and 30.97% burned area, respectively. The dominated vegetation types with high-burning severity were evergreen coniferous forest, broadleaf and conifer mixed forest, and brushwood, which were accounted for 50.37%, 52.22%, and 59.49%, respectively. The proportion of high severity burned areas increased with the ascending slope. 【Conclusion】 The post-fire NDVI showed a increasing trend generally. NDVI value of each vegetation type in the area with high-burning severity was significantly lower than the low and moderate burning severity areas, except for the grassland. But there was no significant difference in NDVI between the areas with low and moderate burning severity. In the second year, the vegetation coverage in high burning severity areas reached the minimum. The NDVI of these vegetation types in low burning severity areas recovered to pre-fire level in 6 years after fire. The coverage of broadleaf and conifer mixed forests recovered faster than other forest types. Fire severity affected forest vertical structure. The burned forests had greater shrub coverage than un-burned ones, and this phenomenon was more obvious in the forests with high fire severity. The natural restoration of brushwood, grassland and marsh was faster than that of forests, thus these areas don't need artificial aids to update. Natural restoration of the tree layer in forests with high-burning severity is very slow, the artificial update will speed up the succession process of forest communities. Periodic drought has an influence on NDVI, especially for the post-fire grassland. The two-factor ANOVA showed that vegetation type and fire severity had a significant influence on the vegetation index. dNDVI can reflect the changes of the vegetation well, which has a good temporal and spatial availability and plays an important role in monitoring the post-fire vegetation restoration.

【Objective】To reduce the testing cost and enhance the research reliability and efficiency, this paper introduced a new rapid detection method for testing VOC released from three-layer parquet. The M-CTE thermal extractor was explored to analyze the effect of environmental factors about release characteristics of VOC on the stable phase and to find the correlation between the rapid detection and 1 m³ traditional climate box method. 【Method】This paper established a single factor experiment matched to the appropriate environmental conditions and to analyze the release rule of VOC under different temperature, relative humidity, ratio of air exchange rate and loading factor by using rapid sampling device and GC-MS conjunctively. On the one hand, the main components and release characteristics of the VOC released from three-layer parquet were probed. On the other hand, the influence of various environmental factors on VOC under equilibrium condition was analyzed. According to the release rule, the best condition was determined by rapid detection method. Meanwhile, the 1m³ traditional climate box method was used to characterize the concentration released during the process of natural attenuation. The data measured from the two kind of method was compared and the correlation was established. 【Result】Results showed that: as the main components of VOC emission released from three-layer parquet, aromatics and esters had obvious changing trend in concentration. Besides some parts of alkanes, alkenes, aldehydes and ketones, small amounts of ethers, alcohols and acids were also found. Furthermore, the TVOC equilibrium concentration increased with the raise of temperature and relative humidity, but the higher the temperature, the less impact of humidity on it. Ratio of air exchange rate and loading factor had remarkable effect on TVOC emissions under high temperature and high moisture condition, the smaller the ratio of air exchange rate and loading factor, the larger the TVOC concentration were found from three-layer parquet in the stage of stable emission. 【Conclusion】By comparing the data of 1 m³ traditional climate box method, we found the trend of VOC release was basically consistent and they had the same compounds. With the time going, the release quantity of TVOC gradually fell to a stable trend. The main components of VOC, esters and aromatic hydrocarbons, were derived from the organic solvent on surface working. Thus, environment friendly coating was recommended. High temperature and high moisture had a significant impact on release quantity of VOC from three-layer parquet by rapid detection method due to the synergy effect of temperature and humidity. The release quantity of VOC was apparently affected by the ratio of air exchange rate and loading factor under high temperature and moisture. The release rate of VOC tested by rapid detection method was apparently fast and reliable. Therefore, the new method could be used for rapid detection of VOC released from wood-based panels to deal with specific problems in the manufacturing process and improve the quality of products.

【Objective】 SPF dimension lumber is a principal material for light-frame timber structures. In this paper, modulus of elasticity (MOE) of SPF dimension lumbers was accurately measured by frequency method. The feasibility of the measured data was studied by Weibull distribution. Then, the data was fitted linearly and verified by K-S method. Meanwhile, a series of possible Weibull parameters was obtained by linear fitting of MOE data in Weibull coordinate. 【Method】 We randomly extract SPF dimension lumbers with capacity of 300 from Nanjing Cogent Home Manufactory Ltd. We realize free beam of test samples by supporting structure hung vertically and freely with elastic rope. The accuracy of free beam realization is proved by the result of modal test. Under transient excitation, the elastic modulus value of the samples is obtained by testing their first transverse bending frequency. The correctness of the test results of frequency method is proved by stress wave method. To exactly evaluate the quality of SPF dimensional lumbers, the testing data was deeply studied by using methods such as Weibull distribution, K-S method in normal distribution, calculation of probability data of MOE value under given values and probability distribution method. 【Result】 A good correlation was found between elastic modulus tested with frequency method and that tested with wave-speed method. As can be seen from the K-S testing results of Weibull distribution and normal distribution, the elastic modulus of SPF dimension lumbers is not subjected to two-parameter Weibull distribution (E_u=0), but it is subjected to three-parameter Weibull distribution, in which location parameter E_u is larger than half of the minimum test value. By analyzing the probability data of MOE value under given values for the total SPF dimension lumbers, the calculated probability values are stable and similar when using 3 500, 4 000 and 4 500 MPa as the given value of E_u. In this case, the given values of E_u are 63%, 72% and 81% of the minimum value of elastic modulus (5 526 MPa), respectively. Therefore, it is recommended to use the value that is 60%-80% of the minimum actual data as the given value of location parameter E_u in three-parameter Weibull distribution. Probabilities for elastic modulus of SPF dimension lumbers calculated with given value in three-parameter Weibull distribution and normal distribution are equal. According to the probability distribution curve and density curve, probability density in Weibull is slightly asymmetric to its mean value (9 997 MPa), which is different from probability density curve in normal distribution; Probability curve in normal distribution is a little higher than that in Weibull distribution when elastic modulus is less than 7 000 MPa. However, the results would opposite when the elastic modulus is more than 7 000 MPa. 【Conclusion】 Modal test verifies testing unit in the work and realizes the supporting conditions for free hanging of test lumbers. Test schemes of frequency method are put forward to ensure the testing precision of natural frequency of the first bending mode and reliably calculate elastic modulus of SPF dimension lumbers; Testing elastic modulus of SPF dimension lumbers by instantaneous aroused frequency method has virtues of convenience, fast, repeatability and accurate; A good correlation was found between elastic modulus tested with frequency method and that tested with wave-speed method. Such a correlation verifies correctness of elastic modulus tested with frequency method. Results tested by the K-S test method showed that general elastic modulus of SPF dimension lumbers obeyed three-parameter Weibull distribution and normal distribution, but not obeyed two-parameter Weibull distribution. Probability of elastic modulus calculated in normal distribution, which is less than 7 000 MPa, is higher than that calculated in Weibull distribution. In other scope, however, probabilities calculated in these two distribution ways are identical; Probability density curve for overall elastic modulus of SPF dimension lumbers in three-parameter Weibull distribution is slightly asymmetric; It is recommended to use 60%-80% of the minimum test data as location parameter E_u when the parameters of Weibull distribution is determined. The overall average and standard deviation of MOE values of total SPF dimension lumbers were calculated. The probabilities of MOE values under given values were also calculated. As a result, the calculated probabilities were same, except the fact that probabilities calculated by normal distribution were higher than those calculated by Weibull distribution when the MOE values were within the scope of low end. To evaluate the quality of these SPF dimension lumbers, the methods of three-parameters Weibull distribution and normal distribution were particularly used to calculate the probability that general MOE value was less than 8 000 MPa (the minimum standard value for Canadian No.2 lumbers), and the probability values were 13.8% and 13.6% respectively.

【Objective】 1-Deoxynojirimycin (DNJ) is one of the important natural active substances with good hypoglycemic effect. Mulberry has a relatively high DNJ content. To obtain high extraction rate from ramulus mori, the microwave-ultrasonic assisted technology was optimized. Meanwhile, to get DNJ contribution degree to α-glucosidase inhibitory activity in ramulus mori water extract, the relationship between DNJ content and α-glucosidase inhibitory activity was analyzed. The present study would provide a basis for DNJ extraction, separation, and polar distribution of α-glucosidase inhibitors. 【Method】9-Fluorenylmethyl chloroformate was used as DNJ derivatization reagent to make up for the shortcomings of DNJ that does not hold the UV absorption characteristic. Then, quantitative and qualitative analysises of DNJ had been done at a wavelength of 254 nm by high performance liquid chromatography. The optimal dimension of ultrasonic processing time, microwave processing time and solvent-to-sample ratio were obtained by single factor experiment. The optimized values including sum of squares, mean square, p-value of three-factor of face-centered cube design, regression equation and corresponding optimal extraction condition were gotten by response surface methodology. Based on the results, systematic solvent method was used to extract concentrated extracts. α-Glucosidase inhibitory activity (through the detection of decomposition rate of α-glucosidase to 4-nitrophenyl-α-D-glucopyranoside at a wavelength of 415 nm by microplate reader) and DNJ content were calculated. The relationship between them was also analyzed in four parts extracted by petroleum ether, ethyl acetate, n-butyl alcoho and water in turn. 【Result】Microwave processing time 9.60 min, ultrasonic processing time 30.89 min and solvent-to-sample ratio 46.47 mL·g^-1 were found to be the optimal condition for extraction with 0.05 mol·L^-1 HCl. The yield was 0.205%. The fitting rate between test value and the optimal value was 99.27%. The test yield of DNJ increased by 10.86% comparing with that of the control group. The DNJ content in n-butyl alcohol part was the highest. The second was found in the ethyl acetate part, and the third was found in the water part. Petroleum ether part had no DNJ. It informed that the extraction effect of n-butyl alcohol was the best. The inhibition curve trend of n-butyl alcohol part was close to ethyl acetate part, and that of water part and petroleum ether part was similar. The 4 parts had apparent difference in IC₅₀ value. It suggested that some differences in polarity existed among α-glucosidase inhibitors in ramulus mori combined with the content distribution of DNJ. DNJ concentration, which was called "DNJ content at this concentration", was calculated from 50% inhibiting concentration based on DNJ content of each extraction part. "DNJ content at this concentration" of n-butyl alcohol part and DNJ IC₅₀ had no apparent difference. It indicated that the α-glucosidase inhibitors of n-butyl alcohol part was almost entirely DNJ. A small amount of DNJ was in water part, but its activity was relatively smaller. It may be due to some components like polysaccharide with the ability of improving α-glucosidase inhibitory activity were possible or some sticky substances that affected the combination of DNJ and enzyme. "DNJ content at this concentration" of ethyl acetate part was smaller than DNJ IC₅₀. This may be because some components like flavone which had enhancement/synergistic function with DNJ or it was possible that some components like alkaloids, coumarins and flavone glycoside etc. had similar activity with DNJ. Petroleum ether part had no DNJ, but had a certain activity. It provided that some other hypoglycemic active compounds with less polarity and lower activity than DNJ were existed in ramulus mori extracts. 【Conclusion】Crushed fresh ramulus mori was treated by microwave, which had both drying effect and assistant extraction effect. Then, extraction was done under ultrasonic conditions. The operation could improve the extraction efficiency of DNJ. The main α-glucosidase inhibitor was DNJ, but there were also some other compounds with less polarity and lower activity than DNJ in ramulus mori. The results are conducive for the further study of DNJ extraction and the composition of hypoglycemic activity compounds in mulberry.

As an important method to measure the micro and nano mechanical properties of materials, micromechanical characterization technique has been already extensively used to study the ultrastructure and mechanical behavior of materials. With the development of characterization technique, research scale shrank tremendously from nano to ultra-nano scale, from molecular to super-molecular scale, even to particle scale. Micromechanical characterization technique can be classified into two types according to the specimen information: nano mechanical testing technique (probe technique) and ultra-nano mechanical testing technique (microscopy techniques). The nano mechanical testing technique included quasi-static nanoindentation, dynamic nanoindentation and dynamic modulus imaging. The ultra-nano mechanical testing technique included atomic force microscopy (AFM) and new techniques based on AFM. Wood is a porous and layered heterogeneous anisotropic natural polymer. It is composed of layers with varying thickness. Cell wall is a central factor determining the properties of wood and wood fiber materials. It is also the essential stressed structure of wood. The mechanical properties of wood cell are depended on the wall layer structure, distribution and combination of chemical compositions. Researching the nano mechanical properties, distribution and affection of cell walls is critical for effective designing of wood and modified wood. Since nanoindentation was first successfully applied in wood cells of nature wood by Wimmer and his colleagues, scholars at home and abroad had generally adopted quasi-static nanoindentation and dynamic nanoindentation to study the nano mechanical properties of cell walls, such as hardness, modulus, creep properties, viscoelasticity, etc. As an interfacial layer or an interfacial phase with nano-scale thickness, the interfaces of wood materials impact their strength, stiffness and fracture toughness. Interfacial mechanics are the key of the whole mechanical properties of wood-based composites. They are also major causes of deformation and strength descent. The researches of the attributes and characteristics of interface are of great value of property evaluating and design optimizing of wood-based composites. The main researches in wood science field included bonding interface, interface of fiber reinforced polymers and micromechanics of coating over the woodworks. Micromechanical characterization technique was tending to high resolution and quantitative evaluation with researching scale shrinking, and already can be performed mechanical information imaging with nano resolution. Development of micromechanical characterization technique can provide great convenience for wood science research. However, tremendous room is needed for improvement. In the future, we should focus on the following three topics: Firstly, to conduct micromechanical technique standardization research, specify testing process and to ensure testing results consistency and reliability. Secondly, to establish relatively complete mechanical system from macrocosm to microcosm, and to further dissect mechanical behavior and failure mechanisms. Thirdly, to build the micro coupling techniques between mechanical, chemical, physical and environmental, so as to enrich the study of wood and wood-based composites at nano scale.

【Objective】Distylium chinense as a shrub will be inevitably subjected to low light conditions when used in urban landscapes, it is essential to understand how the low light conditions affect the growth of D. chinense. A shading experiment was conducted to study the effects of different shading intensities on growth, photosynthesis and chlorophyll fluorescence parameters of D. chinense seedlings and to analyze the responses of the seedlings to the shading.【Method】Three intensities of artificial shading were installed, full light (Control; CK), moderate shading (25% of full light; L1) and heavy shading (7% of full light; L2), and the growth, photosynthesis and chlorophyll fluorescence parameters of D. chinense seedlings under different shading intensities were measured. 【Result】After shading for 60 d, the increment of basal diameter and specific leaf weight in L1 and L2 were decreased significantly, and leaf length and maximum leaf width in L1 and L2 were increased significantly compared to the CK. The increment of plant height was significantly larger in L1 than in CK, but no significant difference was found between L2 and CK. The shading has led to decline of maximum net photosynthetic rate, dark respiration rate, light compensation point and light saturation point, and the decline gradually intensified with the intensity of shading. Compared to the CK, the maximum net photosynthetic rate, dark respiration rate, light compensation point and light saturation point in L1 decreased by 11.8%,46.3%,48.6%, and 15.5%, respectively, and the maximum net photosynthetic rate, dark respiration rate, light compensation point and light saturation point in L2 decreased by 35.2%,65.7%,64.2%,and 20.4%, respectively. The effect of shading on apparent quantum efficiency was not significant, no significant differences in apparent quantum efficiency were found between the shading treatments (L1 and L2) and the CK after shading for 60 d. Compared to the CK, the shading had resulted in significant increase of the maximal photochemical efficiency in L1 but not in L2, and significant decrease of the photochemical quenching and electron transport rate in L1, significant decrease of the photochemical quenching but not the electron transport rate in L2.Although shading has resulted in decreases of non-photochemical quenching, but not at a significant level compared to the CK. 【Conclusion】Results indicated that D. chinense seedlings had a strongly shade-tolerance. Shading allowed the trees to capture more energy and to improve the efficiency of utilizing low light intensity through regulating the morphological characteristics (such as increasing plant height, leaf length and maximum leaf width and reducing specific leaf weight) and photosynthetic physiological characteristics (such as reducing the light compensation point and the light saturation point and maintain a relatively high apparent quantum efficiency and maximal photochemical efficiency), and also to reduce the consumption of photosynthetic products through reducing the energy distribution for the growth of basal diameter and the dark respiration rate of leaves. Therefore, an attempt might be made to grow D. chinense as a shade-tolerant tree species together with other arbor trees in urban landscapes.

【Objective】Vatica mangachapoi is an endangered tree species distributed naturally in Hainan Island, China. Its population decreased rapidly along with heavy loss of natural forest resources and habitat fragmentation due to over-harvesting and devastating forests for arable land. Efficient strategies are urgently needed for conserving natural forest resources of this species. Moreover, the taxonomy of this species is in controversy, taxonomic status of some varieties still need to be proved. Properties of fruits and leaves were measured for trees sampled from different populations to reveal phenotypic variations within and among natural populations. The study would provide scientific evidences for conservation and management of natural forests, and collection, conservation and utilization of genetic resources of the species, and provide basic data for revision of the taxonomy of species and its varieties. 【Method】 Based on surveys of whole range of natural distribution of V. mangachapoi in Hainan Island, 17 traits of fruit and leaf morphology were investigated for 133 individuals in 9 natural populations, and level of phenotypic diversity in its natural populations was assessed, and relationship between the diversity level and geographic and environmental factors was estimated using nest design, multiple comparison test, correlation analysis and cluster analysis.【Result】The variance analysis showed significant differences in the 17 morphological traits of fruit and leaf both within and among populations, indicating abundant variation among and within populations. The within-population variation (50.57%) was far greater than the among-population variation (11.38%); and the average phenotypic population differentiation coefficient was 18.31% with a range from 4.52% for the number of lateral leaf veins to 40.31% for the length/width ratio of the short sepal. Correlation analysis revealed that there were significant positive correlations between leaf length and petiole length, leaf length/width ratio and distance from the widest position to leaf base, while the length of long fruit sepals were in significantly negative correlation with the number of lateral leaf veins and petiole length. No significant correlation was found between fruit and leaf traits and mean annual air temperature and precipitation. While there were significantly negative correlation between number of lateral vein, leaf length and mean air temperature in January, and the number of lateral veins and petiole length increased remarkably with the increment of elevation. The 9 natural populations were divided into 3 groups by UPGMA cluster analysis based on Euclidean distance calculated from phenotypic traits.【Conclusion】It is important to conserve the remaining natural forests and habitats of V. mangachapoi, and in particular, more attention need to be paid to conservation of populations with abundant variations such as Kafaling (Population 4) and populations with special soil conditions such as Shimeiwan (Population 7). Within-population variation was the main source of variation, more individual trees and fewer populations should be used for genetic improvement and conservation of genetic resources. Furthermore, the findings of the present study do not support the new species and varieties in the Hainan Island which were published previously since morphological variation of fruit and leaf varied greatly and continuously, and the variation range were of considerable overlap among individuals within population and among all populations.

【Objective】 Inonotus hispidus is a species of white rot fungi which mainly grow in the broadleaf tree of standing forest stock, and has medicinal efficacy, therefore with high application value and development value. Glycoside hydrolase can hydrolyze the cellulose into simple sugars which can be used to produce energy substances. 【Method】 In this study, we isolate and purified I. hispidus from Fraxinus mandshurica, and the fungus was preserved for long-term in the PDA cant medium. 【Result】 Total RNA of I. hispidus was extracted using TRIzol reagent. RNA was reversely transcribed to cDNA was analyzed and detected by AMV reverse transcription system, and then constructed cDNA library. The glycoside hydrolase family 5 gene positive sequence by NCBI BLAST, and the full-length of glycoside hydrolase family 5 gene was cloned by RACE, and named as IhGH 5-1 then registered in NCBI. All open reading frames of IhGH 5-1 were identifies by ORF Finder, and the amino acid sequence was deduced. The homologous sequences of glycoside hydrolase family 5 were detected from NCBI, and multiple sequence alignment was conducted by Clustal W. The maximum likelihood tree in WAG+G model was constructed by Mega 5.05. The secondary protein structure of IhGH5-1 was analyzed by PSIPRED server. The three dimensional model of IhGH5-1 was established using SWISS-MODEL, and 3d structure of IhGH5-1 was analyzed with VMD1.8.6. The prokaryotic expression primers were design, and the gene was cloned. The fragment was connected to the pQE-30 UA vector and transformed to E. coli JM109. Expression quantity inducible expression was detected using SDS-PAGE electrophoresis. The glycoside hydrolase activity was measured. Total extracted RNA of I. hispidus was measured by spectrophotometer (OD₂₆₀/OD₂₈₀=2.0,OD₂₆₀/OD₂₃₀>1.8). The cDNA library was successfully constructed and sequenced by Sangon Biotech Company. The 5' end sequence of the RACE was 770 bp, and 3' end sequence (containing PolyA sequence) was 1 562 bp. The whole length of the gene from the 3' end to the 5' end was 1 727 bp. GenBank accession number of the gene was KM368321. The amino acid sequence encoded by this gene contains 300 amino acids, the molecular weight is 31.226 55 kD, and the isoelectric point (pI) is 9.24. Domain structure analysis showed that IhGH5-1 has a conservative catalytic domain structure. The maximum likelihood tree showed that a closer relationship with the other glycoside hydrolase family 5 homologous was from fungus of Ascomycota, such as Thielavia terrestris and Chaetomium globosum. The three-dimensional comparison showed that three-dimensional structure of IhGH5-1 had seven alpha helixs, four beta foldings. It was found that the structure was similar with other fungal glycoside hydrolase family 5 protein spatial structures, and evolutionary relationships were consistent with the maximum likelihood tree analysis. The gene expression and enzymatic assays showed that the product of this gene had the highest relative activity at 65℃. 【Conclution】 The gene cloning and protein structural study of IhGH 5-1 would be a theoretical basis for industrial application of this enzyme.

The wild Bactrian camel is a critically endangered species, and has high adaptability in extreme arid environments of Central Asia. Most researches about wild camel are limited on the field survey as the species is alert and distributed in arid and semi-arid areas. There are great knowledge gaps concerning the behavior ecology of the wild camels. From October to December in 2012, the behavioral time budget and diurnal activity rhythm of four released wild camels (two males and two females) in a semi-free environment were observed by the focal animal sampling method in Gansu Dunhuang Wetland National Nature Reserve. The behaviors were divided into six categories, resting, vigilance, moving, foraging, rumination and ‘the others’. The results showed that there was a significant difference in time expenditure on different behaviors by using the Kruskal-Wallis H test (P<0.01). However,there was no significant difference in time expenditure ratio on different behaviors between males and females by using Mann-Whitney U test (P>0.05). For the males, 28.13%±10.42% of diurnal time was spent on foraging, 23.63%±14.47% on moving, 22.15%±5.46% on vigilance, 18.84%±14.96% on resting, 4.79%±4.45% on rumination and 2.46%±1.98% on ‘the others’. For the females, due to the new environment, most of the time was spent on vigilance, accounting for 28.22%±10.74% of diurnal time, 24.47%±10.92% of diurnal time was on foraging, 19.68%±4.06% on resting, 18.29%±7.14% on moving, 5.48%±4.44% on rumination and 3.86%±2.26% on ‘the others’. As time passed, diurnal time expenditure on resting, vigilance and rumination showed a decreasing trend, on the contrary, time spent on moving and foraging expressed an increasing trend. For the males, the peaks of resting, vigilance and moving, foraging occurred at 13:00-14:00, 10:00-11:00 and 17:00-18:00, 11:00-12:00 and 15:00-16:00, respectively. For the females, the peaks of resting, vigilance and moving, foraging occurred at 14:00-15:00, 10:00-11:00 and 17:00-18:00, 11:00-12:00 and 16:00-17:00, respectively. Among different months, the resting, vigilance and foraging behaviors of females were significantly different (P<0.05). However, results of the Kruskal-Wallis H test suggested that there were no significant differences in all behaviors of males among different months. The behavioral time budget and diurnal activity rhythm of wild camels during initial releasing period expressed the similar strategy like most of ungulates. These results would be helpful to understand wild camels' behavioral ecology, and provide a guide for the conservation and management of wild camels.