We analyzed the soil nutrient dynamics at different vegetation successional stages of Three Gorges reservoir area by space-time substitution. The results showed that the soil pH decreased with the development of positive vegetation succession and presented acidic property. The contents of soil organic matters and available phosphorus increased with the progress of positive vegetation succession. The change of soil organic matters was evergreen broad-leaved forest> coniferous forest> deciduous broadleaved forest> shrub > coniferous forest, while the change of hydrolyable nitrogen was coniferous forest> shrub> coniferous forest> deciduous broadleaved forest> evergreen broad-leaved forest. The contents of organic matters, hydrolytic nitrogen and available phosphorus appeared obvious accumulation in the surface layers of the soil at different vegetation successional stages. Correlation analysis indicated that there were extremely significant correlation between organic matter, hydrolytic nitrogen and available phosphorus which had extremely significantly negative correlative with soil layers. The different vegetation stages had extremely significantly negative correlation with soil pH and hydrolytic nitrogen, but had significantly positive correlative with available phosphorus.

Using the analytic hierarchy process (AHP), we structured a hierarchical indicator system that brought about a set of grading criteria to evaluate forest quality of six forest types, including a monoculture Pinus tabulaeformis stand, a monoculture Quercus liaotungensis stand, a monoculture Betula platyphylla stand, a mixed stand of P. tabulaeformis and Q. liaotungensis, a mixed stand of P. tabulaeformis and B. platyphylla, and a mixed stand of Q. liaotungensis and B. platyphylla, in Caijiachuan Forest Station of Yanan, Shannxi Province, China. Results showed that this evaluation system was composed of three criteria and 8 indexes, which could be used to evaluate these secondary forests in this area. The three criteria were forest structure, stand productivity and regeneration status, respectively, among which forest structure attributes were the most important, followed by regeneration status, and then stand productivity. The relative contribution of each index to the forest quality estimation was in the order of canopy cover (0.356 2), litter depth (0.211 6), proportion of seedlings and saplings to the number of all dominant trees (0.130 5), Pielou index (0.105 8), stock volume (0.082 6), richness index (0.064 4), number of seedlings and saplings (0.037 2), and biomass of shrubs and grasses (0.011 8). This study also showed that the quality of most stands was more or less improved after the implementation of the natural forest protection project, but it was not consistent among forest types studied. More than half of the stands were classified as medium quality, and few stands were evaluated as poor quality. Three stand types, P. tabulaeformis, Q. liaotungensis and mixed P. tabulaeformis-Q.liaotungensis stands, had the highest synthesis evaluating value, with a range of 65-73, followed by the B. platyphylla stand, whereas the mixed stand of Q. liaotungensis-B. platyphylla had the lowest value (less than 60.00). The indicators and evaluation system developed in this study are easy to use for quantifying forest quality, and should be suitable for application in evaluating the secondary forests on Loess Plateau.

Chemical concentrations in rainfall, throughfall, stemflow, soil infiltration and surface runoff were measured in a primeval Picea likiangensis var. linzhiensis forest in Nanyigou of Tibet from October 2006 to July 2007. There were a lower silt concentration of 5.56 mg·L^-1 and pH value of 7.61 in the rainfall outside the forest. SO^2-₄ concentration was highest (7.201 mg·L^-1) of all ions or elements in the rainfall. N concentration was lower (0.505 mg·L^-1). Other elements had relative low concentrations in the rainfall. SO^2-₄ and Zn concentrations were reduced in throughfall, but other elements were increased. All elements had higher concentrations in stemflow than in throughfall. Except for SO^2-₄, other elements displayed a positive canopy leaching. The concentrations of SO^2-₄, Zn and Fe were lower in surface runoff and soil infiltration than in rainfall, while other elements were concentrated in surface runoff and soil infiltration. The stream had more HCO^-₃, K, Ca, Na, Mg, and Cu than rainfall, suggesting loss of those elements in the forest. The stream contained less P, Fe, N, Zn, Cl- and SO^2-₄ than rainfall, due to adsorption in the soil and litter and absorption by plants. Our results provided a basic knowledge for further study on the nutrient cycling and evaluation on role of the forest in the water purification.

In order to provide scientific basis for nutrient management in eucalypt (Eucalyptus grandis) plantations, microelements in the plantations in Sichuan were diagnosed in sixty standard plots by correlation analysis and vector diagnosis to explore supply conditions and the interaction to forest productivity. The results were as follows: 1) there was remarkable correlation between sorption of Cu, Zn and forest productivity; 2) macro elements such as N, P and K were influenced by absorption and supply of microelements, and there were prominent interactions between microelements and macro elements or among microelements, such as synergistic effects of Cu to K, Cu to Fe and Mn to N, antagonistic effects of N to Zn, P to Zn, Ca to Zn, K to Fe, Mn to K and among Cu, Zn, Fe and Mn. 3) Cu was deficient in high altitude area and excessive in low altitude area. Zn behaved dilution except a few standard plots subjected to deficiency. Fe content in the soil changed in large-scale, and was deficient in high pH soil and excessive or antagonistic in low pH soil. Changing pattern of Mn content in the soil was the same as Fe, and it displayed excessive or antagonistic in majority of the area and deficient in minority of the area. B had sufficient supply and was diagnosed antagonistic effect.

The rooting characteristics of the twig cuttings of Pinus massoniana was observed to investigate the dynamic changes of relevant endogenous components during rooting process, including the activity of related oxidative enzymes (PPO,POD,IAAO) and the content of flavonoid and nutritive substances and so on. Results showed that rooting of Pinus massoniana was derived from the callus. When its cutting was treated by root stimulate GGR6 in a suitable concentration, rooting rate and the quality of root system could be significantly enhanced. Moreover, dynamic state of the endogenous components in Pinus massoniana plantlets can also be changed. Changes of the most endogenous components displayed regular pattern during the cutting. The activity of PPO and IAAO increased during induction period of the callus, reached to a peak during the formation period of callus, and started to decrease during the formation of root system. Whereas the activity of POD reached to a peak in the formation of both root systems and callus. The content of endogenous flavonoid decreased gradually at early stage of cutting, increased sharply 30-50 days later and reached to a peak when callus formed considerably, and then it started to decrease gradually. The content changes of flavonoid had relationship with the activity of peroxidase (POD); peak value of the activity of POD was always accompanied by a sharp decrease of the content of flavonoid. The content of soluble sugar increased gradually after cutting, reaching to a peak when most cuttings rooted, and then it decreased gradually. The content of total nitrogen changed irregularly during the whole process and the amplitude of variation was very small.

The callus of Tripterygium wilfordii root was used as materials, effects of different concentrations of 2，4-D，NAA, KT，or 6-BA and their combinations as well as carbon sources were investigated on callus growth and secondary metabolite contents of T. wilfordii. The results showed that 2，4-D promoted callus growth and accumulation of alkaloids. 6-BA inhibited callus growth, but obviously promoted triptolide accumulation. Although KT was suitable for callus growth，but inhibited significantly triptolide accumulation. The medium supplemented with 1.0 mg·L^-12，4-D and 0.5 mg·L^-1KT increased the callus growth, while addition of 1.0 mg·L^-12，4-D and 2.0 mg·L^-1KT increased the alkaloid content.The medium supplemented with 4.0 mg·L^-1 NAA and 0.5 mg·L^-16-BA increased the triptolide content. Sucrose was best for callus growth, maltose was best for triptolide accumulation, while glucose was best for total alkaloid accumulation.

In the present study, one clone of transgenic hybrid aspen（Populus tremula ×P. tremuloides）from tissue culture was used as the materials and non-transgenic clone as the control. The contents of endogenous plant hormones, including IAA, ABA and GA, were measured by ELISA in different genotypes and different rooting types. The purpose was to study effects of changes in endogenous plant hormones, and their interaction on rooting of hybrid aspen during tissue culture. The results showed that there was extremely significant variation in IAA and ABA contents among different rooting types of the ramets, regardless transgenic or non-transgenic plants. GA content from different rooting ramets was all highest with about 400-500 ng·g^-1. In transgenic ramets, ABA and IAA concentrations were relatively low in about 150 and 200 ng·g^-1, respectively, at which they were good for promoting the rooting of the plants. Non-transgenic plants in different rooting types all could get the roots, but the phytohormone contents in direct rooting ramets were generally higher than those of the callus rooting ramets. The low IAA/ABA and high GA/ABA and GA/IAA played an important role in the plant rooting.

Forsythia suspensa is an important Chinese medicine plant, but its bearing rate is low naturally.In order to explore the reason of low capsule setting, the long and short style type of Forsythia suspensa were used for observing pollination and fertilization in self-pollination and cross-pollination by fluorescence microscopy and paraffin slice techniques. The results showed as follows: under the condition of self-pollination, a few of pollen tubes could enter the style canal in long and short style F. suspensa in 48 h after pollination, but no fertilized ovule was observed ultimately in the former and few of fertilized ovule existed in the latter. Under the condition of cross-pollination between the long and short style F. suspensa, the number of pollen tube was more and the growth was faster than that of self-pollination. The pollen tube growing into the ovule took about 168 h after pollination in the long style and about 120 h in the short one. It needed about 18 days to accomplish the fertilization in the both style type.

In order to detect the relationship between VA mycorrhizal fungi and Fraxinus mandshurica roots under fertilization condition, mycorrhizal colonization and root tip morphology, such as root diameter, length and specific root length (SRL) of the first order roots were examined at different soil depth and seasons. This study was conducted at a site of Maoershan Forest Research Station in 2005. The results showed that VA mycorrhizal fungal infection rate in the first order roots was generally reduced 10% under soil N addition, which varied with soil depths and seasons. The infection rate in spring was the highest, followed by that in summer and autumn. The infection rate in 0-10 cm lager of the soil was significant higher compared to the 10-20 cm of the soil. In comparison with non-mycorrhizal roots, VA mycorrhizal infection did not alter root diameter and length, but significantly decreased SRL. Those changes of root tip morphology were consistent in different treatments, soil depths and seasons. The findings suggested that the degree of colonization by VA mycorrhizal fungi in the first order roots of Fraxinus mandshurica was dependent upon the N availability, soil depths and seasons, and the root morphology was changed by VA mycorrhizal fungal colonization, which all useful knowledge to were in understanding principle of fine root longevity and turnover in this forest ecosystem.

The initial stand density of 12-year-old masson pine (Pinus massoniana) was used to study effects and interaction of initial stand density and provenances on growth, stem-form qualities and wood basic density. The results indicated that effects of initial stand density varied considerably on different provenances and traits. DBH and height under living branch were most sensitive to initial stand density, height was next, and stem straightness and wood basic density had little response. The four provenances of Cenxi Guangxi, Xinyi Guangdong, Chongyi Jiangxi and Wuping Fujian had sensitive DBH to initial stand density and grew best under the initial stand density of 2.5 m×2.0 m. Effect of initial stand density on DBH of Gaozhou Guangdong was not remarkable. There were significantly different responses in height under living branch to the initial stand density among all provenances, and increasing initial stand density resulted in an increase in height under living branch. Initial stand density had little influence on stem straightness and wood basic density except for stem straightness of Chongyi Jiangxi and wood basic density of Wuping Fujian. There were no significant differences in effect of initial stand density on DBH, height under living branch, stem straightness and wood basic density between different provenances. Only there existed significant difference in heights in the initial stand density of 1.5 m×2.0 m and 2.5 m×2.0 m between provenances. Interaction of provenances and initial stand density was not found on growth, stem-form quality and wood basic density, and initial stand density did not affect their relative growth performance. However, the interaction of block×provenance×spacing was so significant that optimal site should be given for different provenances in a given initial stand density.

Minicut with gaseous ethylene stimulation is a new tapping method which can increase latex yield. To investigate the physiological mechanism，sucrose, phosphorus and total solid content, and its water potential were measured in the latex from flow area of rubber trees by micro-cut with gaseous ethylene, ethephon treatment or without treatment control, respectively. Differences of these physiological parameters were analyzed between before and after tapping in same treatment, as well as among different treatments. The results showed that the gaseous ethylene stimulation significantly promoted latex yield by increasing rubber flow area of trees. It was found that the difference of dry latex content between before tapping and after stopped flow could be used as an indicator in managing tapping production.

Three-year-old ‘Zaozhong No. 6’ loquat ( Eriobotrya japonica, Fujian Province) seedlings were foliar-sprayed with 0.2, 0.5 and 1.0 mmol·L^-1 of sodium nitroprusside (SNP, as NO donor). They were then subjected to low temperature (-3 ℃) stress in a phytotron. The effects of SNP on some physiological and biochemical indexes of young loquat fruits were studied. The indexes include malondialdehyde (MDA), proline (Pro), hydrogen peroxide (H₂O₂), ascorbic acid (AsA), dehydroascorbic acid (DHA), glutathione (GSH), oxidized glutathione (GSSG) content and the activities of catalase (CAT, EC 1.11.1.6), peroxidase (POD, EC 1.11.1.7), superoxide dismutase (SOD, EC 1.15.1.1) and ascorbate peroxidase (APX, EC 1.11.1.11). This study was to explore the regulation mechanism of exogenous nitric oxide (NO) on cold resistance of young loquat fruits under low temperature stress. The results showed that SNP treatment decreased levels of MDA and H₂O₂ in young loquat fruits after low temperature stress. Moreover, activities of CAT, POD, SOD and APX and Pro concentration of Pro were enhanced to some extent. Ratios of AsA/DHA and GSH/GSSG were increased, respectively. It is concluded that the exogenous NO could enhance the protective enzyme activity and reduce membrane lipid peroxidation, and increase the osmoregulation substance content of young loquat fruits after low temperature stress, resulting in an increase of the cold temperature resistance of young loquat fruits. In this study, we found that the desirable concentration of SNP was 0.5 mmol·L^{- 1}.

Suspension-cultured cell lines of Xanthoceras Sorbifolia were established by using callus induced from mature embryos. Growth characteristics of the cell cultures were further studied. The results showed that the optimum initial amount of inoculum amount was 2 g in 40 mL liquid culture medium, and the optimum concentration of plant hormones was 0.5 mg·L^-1 2,4-D and 0.5 mg·L^-1 6-BA and 0.5 mg·L^-1 NAA, respectively. The highest cell mitotic index appeared on day 10,the cell activity was highest on day 3,and the fresh weight peaked on day 14.

Remote sensing technology in measuring quantitatively the vertical and spatial distribution of forest structure draws more and more domestic and foreign scientists attention, and is an important tool to understand the function of forest ecosystems, forest carbon storages and global carbon cycle. The laser radar is superior in detecting the forest vertical structure to other remote sensing data. The purpose of this study was to establish a model to estimate tree height and biomass by processing the GLAS (geoscience laser altimeter system) waveform data, and make the validation, the precisions for the height and biomass estimation were 93.7% and 91.3%, respectively. The result demonstrated that the precision of estimating tree height and biomass was remarkably improved by using LIDAR, comparing with the traditional methods. This study provided important references for researches on mapping the forest vertical parameters.

Eight fungal strains were isolated from infested parts of diseased seabuckthorn plants，collected at autumn，spring and summer from 2006 to 2007. According to Koch's postulates，the spores of isolates from the infested parts were used as inoculums for inoculating seedlings and 12-year-old seabuckthorn plants. The same disease symptoms were reproduced with isolates. Three strains were recovered after Koch test. Original isolates and recovered strains were identified as Fusarium sporotrichioides based on morphological characteristics and 18S rDNA sequence analysis (100% nucleotide identity). The pathogen was able to grow on or in the leaf，branch，trunk and root of seabuckthorn plants，and there was difference in pathogenicity between the pathogen strains which grow on or in different parts of plant. This is the first report that F. sporotrichioides is the pathogen of seabuckthorn dry shrink in Heilongjiang Province.

Changes of hydrogen peroxide (H₂O₂) as well as peroxidase (POD) in the tissues of diseased, healthy, mechanical wounded and phytoplasma graft-transmitted tissue-cultured plantlets of different paulownia clones were investigated using histochemical methods. H₂O₂ localization by DAB staining method showed that the H₂O₂ did not significantly accumulated in both diseased and healthy plantlets of intact plants. After wounding treatment, both diseased and healthy tissues induced H₂O₂ accumulation, and the H₂O₂ in healthy tissues was more than the diseased ones. POD activity in the vascular bundles of severe diseased plants was highest, followed by that of plants with light symptoms, and then asymptomatic and uninfected plantlets. Mesophyllous tissues was lower POD activity than the veins. At the early stage (within 3 days) of graft-inoculation by means of inserting infected scion onto healthy stock, changes in the POD activity and H₂O₂ content had similar pattern as the mechanical wounding reaction, and these effects became weaker 6 days later after graft inoculation. The sustaining H₂O₂ content and high POD activity were detected at the graft union site as well as in the stock in 20 days post graft inoculation using infected scion which appeared witches-broom symptom. Moreover, the systematic induction of H₂O₂ and POD was also detected in the distal parts of main stem or veins of some leaves. H₂O₂ localization by means of KI/starch assay revealed that more H₂O₂ was found in the cell surface of cortex and pith as well as on the wall of conduct tube of xylem in the healthy section and less H₂O₂ was found in the corresponding tissues of diseased plants. When the diseased stem segments were treated with different concentration of H₂O₂ for 1 hour and then in vitro cultured on MS medium, it was demonstrated that the H₂O₂ in 25 to 100 mmol·L^-1 concentrations could obviously relieve symptom on the cultured explants. Ascorbate acid and lowly aerating culture conditions also suppressed symptom development. Certain paulownia clones showed some difference in H₂O₂ accumulation and POD activity in response to phytoplasma infection, which might probably relate to the resistances to phytoplasmas.

To explore the mechanism of a fluorescent brightener, Tinopal LPW, in enhancing infection of LdNPV and the effect of host plants and LdNPV geographic stains on Phenoloxidase in gypsy moths, the 5^th instar larvae of gypsy moth, which are pests of Populus cathayana, Larix principis-rupprechtii and Aarmeniaca sibirica were treated with 3 virus strains (LdNPV-D, LdNPV-H, LdNPV-J) and their mixture with Tinopal LPW with and without Tinopal LPW, respectively. Incubation with distilled water or Tinopal LPW only served as controls. As a result, there were 6 treatments and 2 controls. Phenoloxidase (PO) activity in haemolymph of larvae was measured at 12, 24, 48, 72 and 96 h after the treatments. The experiment (30 larvae per treatment) was replicated three times. The results showed that effects of host plants, virus strain and the brightener on the PO activity in the 5^th instar gypsy moth larvae were significant. PO activity increased after the larva were infected by pure virus 12 h later, and then decreased after 24 h comparing with both distilled water and Tinopal LPW controls. The effect of D-strain, H-strain and J-strain with addition of Tinopal LPW on the phenoloxidase activity of gypsy moth was dependent on the host plants. Larvae fed on A. sibirica, the PO activity was lower than that in larvae treated with virus strains without the brightener, as well as both controls. Larvae fed on poplar or larch, the PO activity in larvae treated with D-strain, or H-strain with the brightener was lower than that in larvae treated with the two stains only, or controls, but there was no difference in Po activity in larvae treated with J-strain between with and without Tinopal LPW addition. Tinopal LPW significantly reduced the PO activity in comparison with distilled water.

An antagonistic bacterium was found in pomegranate fruit and identified as Bacillus subtilis according to its morphology, physiological and biochemical characteristic and 16S rDNA molecular sequence. Antagonistic characteristics displayed that this strain was able to obviously inhibit growth of eight pathogens. For plant pathogenic fungi of Botryosphaeria dothidea, B. parvaand Zythia versoniana, which infect fruits of different trees, the antagonistic bacterium increased mycelia to branch and caused some mycelial cells to distort and fracture and protoplasm to condense. With the bacterium infected, the top and middle mycelial cells intumescentiaed into sphere and oval or bead-like, some intumescentiaed mycelial top cells obviously clustered together and the color became dark, with the mycelial cell intumescentiaed, the cells turned more transparent and changed into vacuole at last. But for Valsa sordida pathogen causing poplar rot disease, the antagonistic bacterium caused mycelia cells to become slim and fragile and less branch. There was no obvious mycelial tops and the cells did not intumescentia into sphere or bead-like, some mycelia were digested and hard to be recognized. All the above results demonstrated that the antagonistic bacterium had different acting mechanism to different causal pathogens.

To study the impacts of secondary disasters induced by Wenchuan earthquake on soil fauna communities, two plots in previous debris flows and landslide regions and two plots in Cryptomeria fortunei forests, served as control, were set up in Yinchanggou, Pengzhou city. Soil fauna communities in the plots were investigated in November 2008. No soil macrofauna was found in the secondary geological disaster areas, but total 196 soil macrofauna, belonged to 3 phyla, 7 classes, 17 orders and 36 groups (families), were found in two control plots, with average density 65.34 ind.·m^-2. There were 232 soil meso-microfauna, belonged to 3 phyla, 4 classes, 6 orders and 26 groups (families) in two secondary geological disaster plots and 2 747 soil meso-microfauna, belonged to 3 phyla, 7 classes, 9 orders and 64 groups (families) in two control plots. The average densities of secondary geological disaster areas and coutrol areas were 3 222.22 ind.·m^-2 and 38 152.78 ind.·m^-2, respectively. The species group numbers, individual density, and the diversity index (H) and abundance index (D) of three diversity indexes of soil meso-microfauna communities in secondary geological disaster areas were significantly lower than those of the control areas (P<0.01), but the evenness index (E) was significantly higher than that of the control areas (P<0.01). Some scares group extinction and community density decrease were the main reasons for the soil meso-microfauna diversity's changes. Compared with the control areas, individual percent of the soil meso-microfauna species community living in wet environment of the secondary geological disaster areas was declined and that of the species living in drought and middle environment increased. The similarities of soil fauna community between the secondary geological disaster areas and control areas were lower than those within the same areas. The results demonstrated that the earthquake-induced geological disasters had strong disturbed effects on the structures and diversities of soil fauna communities, especially, soil macrofauna.

Both normal growth and eccentric growth poplar clone 107 standing tree were selected for studying materials in this paper. Surface longitudinal growth strain was determined，and fiber morphological properties and shrinkage properties of wood sample beneath which strain determined area were measured also. Relationships between growth strain and selected wood properties were deduced，and the result shown： along with increasing of growth strain，fiber length，ratio of fiber length to width，tangential oven-dry shrinkage and longitudinal oven-dry shrinkage of normal growth tree decreasing slightly，however，fiber width，width of double cell wall，runkel ratio，radial oven-dry shrinkage increasing slightly. Correlations among growth strain and all selected wood properties were insignificant. Along with increasing of growth strain，width of double cell wall，ratio of fiber length to width，longitudinal oven-dry shrinkage，tangential oven-dry shrinkage，radial oven-dry shrinkage of eccentric growth tree decreasing sharply，however，fiber width，runkel ratio increasing sharply，and fiber length increasing slightly. Negative correlation coefficients between growth strain and width of double cell wall，ratio of fiber length to width，longitudinal oven-dry shrinkage，tangential oven-dry shrinkage，radial oven-dry shrinkage were significant，and positive correlation coefficients between growth strain and fiber width，runkel ratio were also significant. However，apparent correlation between growth strain and fiber length have not been found. When normal growth tree which did not contain tension wood was concerned，relationships between strain and fiber morphological properties and wood shrinkage properties were feeble. When it came to eccentric growth tree which contained tension wood，almost all relationships between strain and fiber morphological properties and wood shrinkage properties were tighter than normal growth tree owing to different properties of normal wood and tension wood.

Birch veneer was taken to study dye forecast formula using three stimulate value method of computer technology based on Kubelka-Munk theory. Red sandalwood: reactive brilliant red X-3B 0.116%； reactive yellow X-R 0.219%； reactive blue X-R 0.032%. Blackwood: 0.461%；0.544%； 0.177% respectively. Black walnut:0.119%;0.206%； 0.077% respectively. Teak: 0.122%；0.400%；0.082% respectively. It was found that the method was very effective for wood dyeing, and the formula was found after few times，and the error was less than 5%.

In order to fabricate bamboo particles reinforced PVC composite (BPPC) and optimize hot pressing molding technique，effects of molding temperature and time on the properties of BPPC were studied. BPPC were fabricated with selected parameters of hot pressing time in 5-11 min and molding temperature in 165-190 ℃，and the properties of BPPC were tested. Results showed that physical and mechanical properties of BPPC were modified with the enhancing of molding time and a proper molding time was 8 min. In the rang of 165-190 ℃，physical and mechanical properties of BPPC increased with the increasing of temperature first and then showed a decreasing trend. The best molding temperature of BPPC was 180 ℃. Testing of DSC indicated that molding time has a notably impact on the compatibility of bamboo particle and PVC and a good compatibility was get at 180 ℃. SEM analyses of BPPC prepared with optimized technique demonstrated uniform dispersion of bamboo particles in PVC matrix and a good compatibility between them.

The nano-mechanical properties of the cell wall of two crop straws were investigated by nanoindentation. The results showed: the longitudinal elastic modulus of wheat (Triticum aestivuma) straw was higher than one of rice (Oryza sativa) straw, which was 20.8 and 19.4 GPa, respectively. The values of hardness were 0.65 and 0.50 GPa, respectively. At the nano-scale, the longitudinal elastic modulus in crop straws were lower than that in most of the hardwood species, but higher than that in some softwoods and lyocell fiber. The mean value of hardness of cell walls of crop straws was higher than that of wood and lyocell fiber.

The reaction that the unsaturated bonds of abietic acid was oxidized to yield carbonyl group was investigated by the density functional theory method and the most stable structure of oxidation product was determined by the principle of lowest energy. The thermodynamic properties of the product，such as the values of the Gibbs free energy，the thermal enthalpy，the thermal capacity and the entropy，were predicted by calculations in the present work. A set of oxidants were performed on the oxidation reaction involved. The result was found that the best oxidant was the active oxygen ［O］，the second one was ozone，the third hydrogen peroxide，and in addition，molecular oxygen ［O₂］ was not suitable for this process. Accurate theoretical calculations would provide ways to obtain important chemical and physical information prior to experiments. The work will contribute to the research of rosin and its derivatives in experiment.

Promoting forestland transfer to achieve the scale of forestry operations is required for the development of modern forestry. The forestland transfer is the main content in the collective forest right system reform in China at present. Individual farmers, as a basic unit of forest production, should be the major participant in the forestland transfer. Based on a set of survey data of 222 farmers in 8 villages in Linan and Anji county, Zhejiang Province, this paper analyzed the features of farmers participation in the forestland transfer, from the scale, channels, constraint conditions to the transfer and so on, by using the cross-group statistical methods to analyze the affecting factors in the forestland transfer. The results showed that: the main suppliers in forestland transfer were those younger farmers; and the main demanders were those aged 40-60 years old farmers. Farmers with relatively poor-educated tent to take forestland, while better-educated farmers tent to rent out their forestland. The primary participants in the market of forestland transfer were village cadres. Forestland was transferred from the smaller families with fewer labor forces to the bigger families. Families whose member(s) were engaged in commerce or worked in governmental organizations or institutions had a higher proportion to rent out their forestland. Most farmers participating in forestland transfer usually had a higher family income. Primary suppliers in the forestland transfer were those who had a higher ratio of non-agricultural incomes; and the primary demanders were those who had a relatively lower ratio of non-agricultural incomes.

The reform of the southern collective forest property rights system has brought about a basic structure with decentralizing management on a household basis being the main body in southern collective forest areas. It has been an inevitable trend to practice forestry scale operation through reasonable and systematic forestland circulation and transfer under the precondition of clarifying property rights of management subjects. This paper, based on the case of L County Hunan Province, using the methods of participatory rural appraisal and questionnaire survey, briefly reviews the operation pattern of different types forestland and the circulation desires, analyzes the motives of forestland circulation ,and then points out the appropriate route choice of forestland circulation forms.

The floristic character, community appearance, community structure and species biodiversity of Quercus liaotungensis communities in Lingkong Mountain area were studied to explore adaptive characters of the communities by using the plot investigation methodology. The result showed that the Q. liaotungensis communities in Lingkong Mountain area consisted of around 182 species, displaying an apparent temperate characteristic. The phaenerophyte was of absolute dominance in the life form spectra，which bore the typical appearance characteristics of the warm temperate deciduous broadleaf forest. Although the community structures were stable in different Q. liaotungensis communites, but reserve of seedlings of Q. liaotungensis population was insufficient. The species biodiversity index value varied and fluctuated in different communities and layers, however, pure Q. liaotungensie forests were relatively stable. Based on the thorough studies of different Q. liaotungensis communities in the Lingkong Mountain area, the adaptabilities and the internal mechanisms of Q. liaotungensis communities in the warm temperate zone were illustrated, which provided a scientific foundation for the protection and expansion of the germplasm resources and the sustainable management of Q. liaotungensis

A full length cDNA of light-harvesting chlorophyll a/b(cab) gene was cloned from the first strand of Pinus massoniana cDNA through RT-PCR and RACE-PCR methods，named as cab-Pm1(GenBank accession No. GU073386). The length of cab-Pm1 is 1 062 bp，which contains an open reading frame encoding 274 amino acids，a 67 bp and a 160 bp untranslated region at 5’end and 3’end respectively，and a 25 bp Poly(A) at 3’ end. The bioinformatics analysis indicated that the pI and molecular weight of the protein encoded by cab-Pm1 were predicted to be 5.24 and 28.98 ku respectively，and the protein had one chlorophll a/b binding domain，four protein kinase C phosphorylation sites，seven N-myristoylation sites，two cAMP and cGMP-dependent protein kinase phosphorylation sites. Cab-Pm1 displayed high sequence identity with plant cab gene family isolated previously and was clustered close to cab family genes of gymnosperm plants. The prokaryotic expression vector of cab-Pm1 gene encoding protein was constructed by subcloning the fragment into pET-24a（+）and the gene was expressed in Escherichia coli induced by IPTG. The molecular weight of the induced protein was about 29 ku that was approximate as predicted.

A all-length cDNA of LlMDHAR gene was cloned from Lilium longiflorum cv. ‘White Heaven’by RACE. The gene consisted of 1 502 bp encoding a protein of 434 amino acids. The sequencing indicated that the LlMDHAR gene shared highly homology with other plants. RT-PCR analysis showed that expression of LlMDHAR gene could be detected in the root, bulb and leaf, and the relative high expression occurred in the root and leaf. Under H₂O₂ stress, the expression of LlMDHAR gene was increased with the raising of H₂O₂ concentration.

Diameter distribution is one of the key factors to reflect the characteristic of forest stand. Based on the long-term investigation data on the Jingouling Forest Farm which belongs to the Wangqing Forestry Bureau in Jilin Province，negative-exponential function was used to model the diameter distribution in different years. The parameters a and K were calculated. Result shows that a and K were decreasing along time. Thus，a and K were supposed as functions of time. After the estimating of a and K，the diameter distribution model was established. Then we used this model to predict the diameter distribution，and compared with the observed diameter distribution. Result shows the model we draw in this study is well-behaved. The diameter distribution was usually used to present the instant structure of stand in previous study. This study shed light on the prediction model of diameter distribution，and also it is very important in forest modeling.

An elite variety of Eucommia ulmoides ‘Huazhong No.7’　female plant was selected through selective breeding of superior tree, survey and evaluation of afforestation and regionalization trail. The elite variety had characteristics of strong adaptability and early fructification, high and stable yield with high linolenic acid in kernel. It was fit for establishment of Eucommia orchard for producing gutta-percha and linolenic acid.