[Objective] The green-revertible pattern of leaves of albino Pseudosasa japonica f. akebonosuji are complex.The white parts of the whole white leaf or stripe leaf gradually turn green, and the degree of chloroplast development and the rate of return-green are different in the various leaves. The chlorophyll relative content (SPAD) of the leaves with different green degrees was measured with the non-invasive measurement method, by which we investigated the relationship among chloroplast ultrastructure, photosynthetic pigment content and photosynthetic characteristic of P.japonica f.akebonosuji. This study aimed to shed light to the further study of the green-revertible mechanism and the breeding of ornamental bamboo.[Method] The leaves of P.japonica f. akebonosuji with different green degrees were used in this study, and the mature green leaves served as the control (CK). The leaf samples were divided in to 6 stages according to the green degree, 0, 10%, 30%, 50%, 70% and 90%.The photosynthetic pigment content, photosynthetic characteristics and chlorophyll fluorescence parameters and chloroplast ultrastructure of leaves in each stage were investigated to explore the changes of physiological and biochemical levels in the green-revertible period.[Result]The results showed that albino leaves of Pseudosasa japonica f.akebonosuji had low chlorophylla and chlorophyllb content.Photosynthetic pigment content increased when the white leaves return to green. The chlorophylla, chlorophyllb, total chlorophyll and carotenoid content of the completely returned to green leaves were 87.02%, 98.20%, 89.37%, 85.02% of the natural green leaves,respectively. The Chlorophyllb content of the completely returned to green leaves reached the level of green leaves, but the other pigments didn't. The albino leaves had no photosynthesis. The net photosynthetic rate of the return-green leaves increased significantly, the stomatal conductance became steady in the later stage of regaining green, and the intercellular CO₂ concentration decreased significantly, indicating that the change of photosynthetic rate was affected by non-stomatal factors. The light saturation point of green-revertible leaves increased, the light compensation point decreased and the dark respiration rate was not significantly different from those of the natural green leaf. The rate of apparent quantum yield in 90% green-regaining leaves was 78.66% of the normal leaves. The F_o and NPQ increased firstly and then decreased, but F_v/F_m, Y(Ⅱ) and ETR were significantly raised, indicating when the content of photosynthetic pigment increased, the light-harvesting ability and photochemical conversion efficiency in PSⅡ reaction center were gradually restored. The change of q_P in the early stage of green-regaining progress was slow, and the change of chlorophylla/b reaction center was not affected by the green-regaining process. The chloroplast ultrastructural changed significantly. The chloroplast inner membrane structure of the regaining green leaves was gradually returned to normal, while the lamellar structure of chloroplast in green leaves was clear and uniform.[Conclusion]The accumulation of photosynthetic pigments and reconstruction of thylakoid membrane are the two important non-stomatal factors leading to the recovery of photosynthetic capacity in the green revertible leaves.

[Objective] To compensate a lack of historical data of underground water level in the Lower Tarim River and provide a new method for reconstructing historical changes of underground water level in the arid inland river basin.[Method] Populus euphratica, a dominant species of desert riparian forest, was studied. A total of 58 tree rings were cored from 29 P. euphratica trees in Yingsu section of the Lower Tarim River in September, 2015.48 cores were selected using software of Cofecha and Arstan to set up the width chronology of P. euphratica. The change trends of chronology and underground water level were analyzed by moving-t test, Mann-Kendall trend test and cumulative curve. Relationships between tree ring width and temperature, precipitation, underground water level were analyzed using the Frequencies, one-way ANOVA, Pearson Correlation and Regression Models.[Results]The tree ages of P. euphratica ranged from 40-80 years. Rotten xylem usually occurred when P. euphratica was more than 60 years, and no more than 100 years old P. enphratica with healthy xylem were found in the Yingsu section of Lower Tarim River. Step change point of standard chronology of P. euphratica was 1957, 1967, 1975, and 2000, respectively. There was no significant correlation between the regional climate change factors (temperature, precipitation) and chronology of P. euphratica. Main environmental information of tree rings of P. euphratica was the hydrological process. We successfully reconstructed the historical change of underground water levels from 1933 to 2015 using tree ring width of P. euphratica, which was consistent with the historical records of regional hydrological process.[Conclusions]Effects of regional temperature and precipitation on tree rings of P. euphratica were not significant in the Lower Tarim River. Tree ring of P. euphratica mainly carried the hydrological information, so it could be a new index for researching the historical changes of underground water level in the Lower Tarim River.

[Objective] To reveal the pollen competition in plants of different genders and its competitive mechanism via the exploration of the direction and scope of pollen dispersal of Osmanthus serrulatus, and to investigate the relationship between plaque size and the adaptability of progeny through open-pollination, so as to provide a theoretical and technological basis for further studies of floral evolution, population genetics and conservation strategies of O. serrulatus.[Method] O. serrulatus, an androdioecious plant species, was studied through a statistical investigation of the sex of individuals in 24 samples of different O. serrulatus populations collected from Donglashan Valley of Baoxing County in Sichuan Province. Observations and comparisons of pistil morphology, number of pollen grains, and external features of unisexual male individuals and hermaphrodites of O. serrulatus were made; 10 pairs of polymorphic SSR primers were used to analyze 271 candidate male parents and 494 progeny plants of 24 population samples.[Result] 1) For O. serrulatus in Donglashan Valley, the ratio of male individuals and hermaphrodites was 1:1. The pistils of the flowers of hermaphrodites developed soundly, while the flowers of unisexual males showed a reduced pistil. 2) Calculation at 80% confidence level was performed for 376 progeny trees (76%) to identify the sole male parent. Of all the progeny trees whose male parents had been identified, respectively 213 and 163 progeny trees were derived from male parents and bisexual parents. 3) The average effective dispersion radius for the pollens of the 24 population samples was 46.35±25.62 m. The mating distance of mother plants showed approximate normal distribution, further indicating outcrossing of the plants. Stocking density, altitude, wind direction and other factors may affect the mating pattern of O. serrulatus.[Conclusion] Experiments showed that natural populations of O. serrulatus are functionally androdioecious and self-compatible; and the reproduction system may be a transitional type evolving from hermaphrodite to diclinous.

[Objective]The optimization algorithm was used to optimize the design of clonal distribution of the seed orchard, so as to ensure rich genetic diversity in the next generation while maintaining high genetic gain, and provide advice on the clonal distribution of the high generation seed orchard.[Method]The genetic distance between the parents of Pinus sylvestris var. mongolica was determined using SSR markers and relevant analysis software, the parent trees were selected from the existing P. sylvestris var. mongolica in the National Production Base of Improved Seeds in Honghuaerji of Inner Mongolia. Based on this genetic relationship, the optimization algorithm was used to optimize the clonal deployment by computer simulations, and the original optimization method was improved by accommodating the objectives of the current study. Finally, the optimized clonal deployment was compared with the traditional clonal deployment and other options in a seed orchard.[Result]The seed orchard clonal deployment plan created by optimization algorithm is better than the traditional sequential dislocation method and other methods. This method can keep the maximum distance between the clones which have closer genetic relationship and reduce the chance of inbreeding, therefore enlarging the genetic basis of the offspring to a certain extent.[Conclusion] When the genetic distances between parents were given, the Improved Adaptive Parallel Genetic Algorithm, which was improved by changing the adaptive method based on the traditional Genetic Algorithm, can be used to optimize clonal deployment in seed orchard based on genetic distance.

[Objective] To establish protoplast isolation system for Chinese fir(Cunninghamia lanceolata) leaves, the effects of different factors on protoplast preparation were analyzed by using young leaves of Chinese fir plantlets from tissue culture. Meanwhile, the most effective method for extraction of total RNA from Chinese fir protoplast was chosen through comparison of different RNA extraction methods.[Method] The young leaves of Chinese fir plantlets were selected as explants, and the effects of major factors, such as five enzyme combinations, vacuum treatment time (0, 5, 10, 15, 20 min), osmotic pressure (0.3, 0.4, 0.5, 0.6 mol·L^-1 mannitol), BSA concentration (0.1%, 0.2%, 0.3%, 0.4%) and enzymolysis time (1, 2, 3, 4, 5 h) were investigated to construct optimum protoplasts isolation system for Chinese fir leaves. Seven RNA extraction methods, such as improved Trizol method, improved Trizol+10 μg glycogen method, CTAB-LiCl method, CTAB-LiCl+10 μg glycogen method, improved CTAB-isopropanol method, improved CTAB-isopropanol+10 μg glycogen method and TIANGEN RNA extraction kit were applied to compare the efficiency of RNA extraction from Chinese fir protoplasts.The quality and yield were detected by reference genes and two specific genes.[Result] The optimum condition for protoplast isolation from Chinese fir leaves included a mixed enzyme solution of 1.5% cellulase R-10, 0.2% pectolyase Y-23, 1% macerozy R-10, 0.5 mol·L^-1 mannitol and 0.3%BSA, vacuum treatment for 10 min, and digestion for 2 h. High activity and pure protoplasts could be prepared from Chinese fir leaves by using the optimum condition. The protoplast yield could reach to 7.26×10⁶ per gram with 94% viability rate. All seven methods could extract RNA from protoplasts. However there were obvious differences between different methods. RNA degradation was found in the improved Trizol method, improved Trizol+10 μg glycogen method, CTAB-LiCl method and CTAB-LiCl+10 μg glycogen method.While, the other three methods obtained good RNA quality, of which the values of OD_260/280 and OD_260/230 were in the normal range of 1.8-2.0. Additionally, the yield of RNA was the highest in improved CTAB-isopropanol+10 μg glycogen method, up to 6.89 μg per 10⁶ protoplasts, which was 1.73 times and 1.58 times of the improved CTAB-isopropanol and TIANGEN RNA extraction kit, respectively. In conclusion, the modified CTAB-isopropanol+10 μg glycogen method was most efficient for RNA extraction from Chinese fir protoplasts.[Conclusion] In this study, by using the young leaves of Chinese fir plantlets, a protoplast isolation technique was established with the condition of 1.5% cellulase R-10, 0.2% pectolyase Y-23, 1% macerozy R-10, 0.5 mol·L^-1 mannitol and 0.3%BSA, 10 min vacuum treatment, and 2 h enzymolysis. Meanwhile, the improved CTAB-isopropanol+10 μg glycogen method could be used to extract total RNA from Chinese fir protoplasts with the average yield of 6.89 μg per 10⁶ protoplasts. All the results of this study provided an important basis for the functional analysis of key genes and their application in breeding of Chinese fir.

[Objective]The role of plant roots in maintaining slope stability and soil mass has been widely recognized. However, the interaction between soil and roots is complex, so that it is difficult to accurately quantify the effect of root reinforcement. In order to improve the accuracy of root reinforcement quantification, in terms of the different mode of destroying roots in soil, this paper analyzed the tensile and pull-out strength of roots under various growth periods using direct shear tests and root strength tests.[Method]A breakaway type instrument was designed on the basis of traditional direct shear apparatus, which can test the in-situ shear strength of root soil composite of potting plants (as shear box). In this study, 12 well-grown 3-years-old Symplocos saplings were planted in direct shear boxes. The tensile strength, pull-out strength of roots and shear strength of roots-soil composite were measured in one month, 4 months and one year after the plants were transplanted. The relationship between single root diameter and single root tensile strength and pull-out strength was analyzed. On the time scale, the changes in the related parameters of the root system were investigated, the interaction mechanism of root and soil and the destruction of root system were analyzed, and the existing Wu model was optimized, and the effect of root soil consolidation in the dynamic growth process was evaluated.[Result] The results reveal that 1) The root tensile and pull-out strength collectively played an important role in root soil reinforcement. In the process of plant growth, the effect of pull-out strength on soil consolidation was more significant than that of tensile strength; 2) The shear strength of root-soil composite significantly increased after four months, however the increasing rate reduced after 1 year. The percentage of breaking roots, especially for fine roots, increased with the increase of planting time; 3) The root tensile and pull-out strength were added to the calculation of plant root soil consolidation model, the proposed model can estimate the reinforcement effects more accurately with a deviation merely 8.13%.[Conclusion]After one year's growth, the quantity of plant roots did not change greatly, and the root tensile strength, which is determined by its material properties, did not change obviously. However, the bonding between soil and root increased significantly because a number of roots tend to break when the soil was sheared, leading to increased root reinforcement with the plant growth.

[Objective] We cloned and characterized the cold shock domain-containing protein (CSP) gene in Chinese white pine beetle, Dendroctonus armandi in order to reveal the molecular mechanism in adaptability and cold-tolerance of D. armandi.[Method] The DarmCSP cDNA fragment of D. armandi was cloned. The phylogynetic tree was constructed with MEGA. The expression profiles of DarmCSP in D. armandi exposed to different low temperatures for different time series were detected by using real-time quantitative PCR.[Result]The cloned gene was named as DarmCSP. The result showed that the sequence from DarmCSP gene shared the highest level of amino acid sequence identity with CSP of the bark beetle species (Dendroctonus ponderosae) (92%). Real-time PCR analysis was used to detect the transcript levels of DarmCSP in D. armandi. The DarmCSP expression was up-regulated during the overwintering stage. The DarmCSP expression level of overwintering larvae (Jan. 2015) was 4.26 higher more than that early winter stage (Sep. 2014) and 2.90 higher than late winter stage (Mar. 2015). The DarmCSP expressions of overwintering larvae (Jan. 2015) and oversummering adults (Jul. 2015) were both up-regulated when beetles were exposed at different low temperatures for different duration. DarmCSP expression level of D. armandi increased with the exposure time increasing from 1 h to 24 h at -10℃, reaching its highest expression level at the time of 24 h. The DarmCSP reached the highest expression levels all for 12 h when larvae were exposed among -2, -4, -6 and -8℃. The DarmCSP can be induced from 0℃ to -10℃. The DarmCSP expression of oversummering adults was also up-regulated when beetles were exposed from 4℃ to -6℃. However, the expression level was lower than that of overwintering larvae.[Conclusion] The result of this study demonstrated that the DarmCSP expression in D. armandi can be induced by low temperature. The molecular changes participate in the adaptation process of D. armandi to low temperature. Our result can contribute more to further study on CSP and its physiological biochemical mechanism of Chinese white pine beetle.

[Objective]In this study, a novel cDNA encoding the chemosensory protein3 (CresCSP3) from Clostera restitura was cloned and its characteristics and its expression in different developmental stages, different age of days and different tissues, in order to identify the role of CSP in insects chemical sensory system.[Method]The full length cDNA sequence of the covering coding region of CresCSP3 was cloned by using transcriptional sequence and RACE technique, and the signal peptide, isoelectric point, molecular mass, and three-dimensional structure of the signal peptide were predicted by using online tools. The homology was compared by using BLAST, the phylogenetic tree was constructed using a neighbor-joining method with MEGA 6.0 software, and the affinity between CresCSP3 and CSPs from other 12 lepidopteran species was analyzed. The expression profiles of CresCSP3 in every instar larval, at different ages after emergence and in different tissues were assayed using real-time quantitative PCR (qRT-PCR).[Result]A new chemosensory protein was cloned from C. restitura named CresCSP3. The full length of CresCSP3 cDNA is 545 bp, containing a 61 bp non-coding district in 5' end, a 100 bp non-coding district in 3' end, and a 384 bp open reading frame encoding a putative 127 amino acids with a molecular mass of 14.34 kD and an electric point of 5.75. The deduced amino acid sequence possesses a putative signal peptide of 18 amino acids. The three-dimensional structure of CresCSP3 is composed of 6 α-helices, forming a hydrophobic cavity, which conform to the typical CSPs structural model. The amino acid sequence of CresCSP3 shows the highest identity (61%) with the CSPs of Plutella xylostella, and the lowest identity with Ectropis oblique hypulina CSP2 with only 27%. Phylogenetic tree analysis showed that CresCSP3 was not clustered into one branch with any other CSPs among the 12 lepidopteran species. The qRT-PCR analysis revealed that the CresCSP3 was expressed in the whole development stages and it was predominantly expressed in 4th instar. For adults, CresCSP3 was distributed in the both male and female antennae, but the expression pattern differed:the CresCSP3 was predominantly expressed in 3-4 days old male adults but it was highly identified in 4-5 days old female adults. It also showed that CresCSP3 was expressed in heads, antennae, feet and wings while highly expressed in antennae both in male and female.[Conclusion]The sequence characteristics of nucleotides and amino acids of CresCSP3 were clarified. CresCSP3 had a distant relationship with CSPs from other lepidopteran insects, which reveals the diversity of chemosensory proteins family. The expression patterns of CresCSP3 in different developmental stages indicated that CresCSP3 might participate in the host localization during larval feeding. The expression patterns of CresCSP3 in the antennae of male and female adults at different ages showed that CSP3 was involved in mating and spouse localization. Besides, it might also be involved in host localization during female laying. The expression of CresCSP3 was the highest in the antennae, which may probably be because antennae are the main structure to feel the external volatile odor molecules. The wings, feet and head were also involved in the perception of the external environment to some extent. CresCSP3 was widely distributed in the insects, indicating that it may play an important role in identifying the complex chemical signals in the environment so that the insect can react accurately.

[Objective] In order to clarify the softening and flattening mechanisms of oaks in different cutting directions, bending creep behavior of different oak boards(longitudinal plain-sawed lumber, longitudinal quarter-sawed lumber, transverse plain-sawed lumber and transverse quarter-sawed lumber) were investigated by dynamic mechanical analysis(DMA).[Method] DMA creep curves of oak samples were analyzed and fitting by Burger model and general Kelvin model to evaluate the creep performance of different oak samples.[Result] The results showed that both Burger model and general Kelvin model could describe creep characteristic of oak well, R² of Burger model is larger than 0.90 and R² of general Kelvin model is larger than 0.99. Under the same moisture content, the elastic module(E₀) and bulk viscosity(η_n), which were calculated by general Kelvin model, decreased with temperature increasing from 70 to 90℃. The retarded time(τ'), which were calculated by Burger model, increased when the temperature increased from 70 to 90℃. According to η_n, it was the following order:longitudinal plain-sawed lumber > longitudinal quarter-sawed lumber > transverse quarter-sawed lumber > transverse plain-sawed lumber.[Conclusion] It was suggested that the higher the temperature, the much easier for the oak board flattening. Transverse warp of oak board was easier to flat than that of longitudinal warp. Longitudinal warp of plain-sawed lumber was harder to flat than quarter-sawed lumber. However, comparing to quarter-sawed lumber, restoration of transverse warp for plain-sawed lumber was easier.

[Objective]The aim of this study is to explore the influence of different post-treatment and drying methods on weight percent gain (WPG) and dimensional stability of the melamine-urea-formaldehyde (MUF) resin impregnated wood, to provide reference to modification technique with resin-impregnation.[Method]The MUF resin solutions with concentrations of 5%, 10%, 15%, 25% were used to impregnate poplar wood (Populus tomentosa) using the full cell treatment schedule. After the impregnation, specimens were treated respectively under 4 conditions:air drying for seven days, storing in high humidity condition for seven days, soaked in the resin solution for seven days, and no post-treatment. Subsequently, the post-treated specimens were sorted into two groups and took direct drying and wet drying respectively, followed by the measurements of the WPG and bulking. Finally, resin treated specimens and untreated specimens were immersed in distilled water for fourteen days. Once the specimens were taken out from the distilled water, the anti-swelling efficiency and the ratio of radial swelling to tangential swelling were determined.[Result]It was found that there was a significant positive correlation between WPG and resin content. The WPG of specimens impregnated with resin content of 5%, 10%, 15%, and 25% was 9.7%, 19.1%, 28.4%, and 50.0% respectively,and no obvious differences in WPG was observed between specimens with different post-treatments. After the same post-treatment, specimens through direct drying had a slightly lower WPG than those through wet drying. Specimens stored in a high humidity condition or soaked in the resin solution after resin impregnation had a higher bulking ratio than those through other post-treatments. Wet drying resulted in a higher bulking ratio than direct drying after the same post-treatment except for the air drying. The changes in anti-swelling efficiency for resin impregnated specimens under different post-treatments corresponded to those in bulking ratio. The radial and tangential swelling of the resin impregnated wood decreased with the increase in WPG, while the ratio of radial swelling to tangential swelling also increased. The ratio of radial swelling to tangential swelling of the resin impregnated specimens at low WPG was smaller than that of the untreated wood, but larger than that of the untreated wood with WPG above about 30%.[Conclusion]1) Post-treatment has less influence on WPG than the drying process. The wet drying process is conducive to resin fixation in wood pores, resulting in a higher WPG. 2) Cell wall bulking ratio is influenced by the post-treatment method as well as the drying process. Storing the specimens in high humidity condition or soaking them into the resin solution after the resin impregnation would result in more resin penetrating into the cell wall. Wet drying process would favor more resin penetrating through and fixing at cell walls, and therefore, result in higher bulking ratio. 3) Anti-swelling efficiency correlates with cell wall bulking ratio of the resin-impregnated specimens, and the higher bulking ratio would results in higher anti-swelling efficiency and better dimensional stability. 4) The ratio of radial swelling to tangential swelling increases with the increase in WPG.

[Objective] In order to put forward a simple and feasible preparation method for detecting the microstructure of wood-based composites, the effect of laser ablation sampling on the surface morphology and microstructure of wood/adhesive interphase were investigated in this paper.[Method] Cryptomeria fortunei/urea-formaldehyde resin(UF) interphase and Cryptomeria fortunei/polyvinyl acetate(PVAc) interphase were chosen as experimental samples. Conventional microtoming method and laser ablation method were used to process the samples, and the surface morphology and microstructure of the treated samples were observed by scanning electronic microscopy.[Result] For conventional microtoming method, burrs and scratches were observed on the sample surface due to mechanical cutting, and the wood cells deformed and even broken. Moreover, the bondline of wood/UF bonding sample was fractured, and the tracheids near the bondline were broken, which was not conductive to investigate both the morphology of bondine and the combination between adhesive and wood cell walls. Although the bondline in wood/PVAc bonding sample was tore, it had less influence on the observation and analysis of interphase microstructure. For laser ablation method, several sputtering traces resulted from small wood or adhesive particles were observed on the sample surface, especially in adhesive region and latewood area. In addition to the scratch defect, laser ablation method can also lead the fracture of parts of the earlywood tracheids positioned a certain distance from bondline, and some of the broken cell walls were left in lumens. However, these defects did not affect the observation of microstructure of wood/adhesive interphase, including the distribution of adhesive in wood cells, the morphology of bondine, the interfacial compatibility between adhesive and wood cell walls and so on. Laser ablation method was suitable for investigating the variation of micro defects in wood/adhesive interphase under different pressures.Results showed that the number and size of both holes in the UF bondline and gaps between adhesive and wood cell walls gradually reduced with the increase of pressure. When the pressure came to 1.2 MPa, slight cracks appeared in wood cell walls and regions between adhesive and wood cell walls.[Conclusion] Comparing with conventional microtoming method, laser ablation method shows its advantages in sample preparation, since the sample needs no preprocessing treatment, and there is no requirement for the sample size. The processing time for samples with larger size and higher density would be longer. The laser ablation method with wide applicability is helpful in studying the microstructure of bonding interphase for wood-based composites.

[Objective] For the safety design and the rational application of domestic dimension lumber in timber structure, the objective of this study was to develop a determination method of the design value of tension strength of domestic dimension lumber.[Method] The Chinese larch dimension lumber (Larix gmelinii) was selected as the research object. Full-size tensile test results of different visual grades (grade Ⅰc, Ⅱc, Ⅲc, Ⅳc) dimension lumber were summarized. By the least square method, the fitted parameters and results for tension strength were obtained under different probability distribution models and different fitting data points. The characteristic values of tension strength were also determined based on the nonparametric method. Finally, the relationships between the reliability index and the partial factor under different fitting data points, probability distribution models, load combinations, and load ratios were investigated by the reliability analysis theory.[Result] The results indicated that there were significant difference of tension strength between different visual grades. The average and the coefficient of variance of tension strength displayed the following order:Ⅰc > Ⅲc > Ⅳc > Ⅱc, Ⅱc < Ⅰc < Ⅲc < Ⅳc, respectively. Compared with the fitting results, the end probability distribution fitted by different models (Normal, Lognormal and 2-P-Weibull) begun to be identical with the decrease of the fitting data points, which was close to the tested values. The calculated reliability index with the lognormal probability distribution model was the highest, and that with the normal probability distribution model was the lowest. With the decrease of the fitting data points, the calculated reliability indexes with different probability distribution models (Normal, Lognormal and 2-P-Weibull) begun to be identical. If the partial factor was the same, with the increase of the load ratio, the calculated reliability indexes under dead load plus residential live load (D+R), or dead load plus office live load (D+O) were increased, however, the calculated reliability indexes under dead load plus snow live load (D+S), or dead load plus wind live load (D+W) changed very little. The partial factor for D+W or D+S was the highest while that for D+O was the lowest.[Conclusion] To determine the design value of tension strength of domestic dimension lumber, this study suggested that the lognormal probability distribution model be selected for the tested probability distribution of tension strength, the parameters of the selected lognormal probability distribution model be determined by the 25 per cent tested data points, the load type of dead load plus residential live load be selected, and the load ratio be 1.0. For Chinese larch dimension lumber, the design values of tension strength of grade Ⅰc, Ⅱc, Ⅲc, Ⅳc were 9.0, 6.8, 5.6 and 2.9 MPa, respectively.

[Objective] 1,2,3,4-butanetetracar boxylic acid(BTCA) cross-linked cellulose nanofibril(CNF) aerogels were used to study the effects of cross-linking degree on the chemical characterization,morphological,and mechanical property of the CNF aerogels,which laid the foundation for further development of functional CNF aerogels.[Method] In this paper,we prepared the cross-linked CNF aerogels with different cross-linking degrees by adjusting the addition ratio of raw materials via freeze drying and post cross-linking method. The chemical characterization,morphological,surface area,pore size distribution,and mechanical property of the CNF aerogels were analyzed by means of Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS),Scanning electron microscopy(SEM),BET measurement and mechanical tests.[Result] Results showed that:1) Compared with those of the pure CNF aerogel,the FTIR and XPS spectra of the BTCA cross-linked CNF aerogel were changed obviously,the absorption peak intensity of hydroxyl(-OH) was observed weaker and that of carbonyl absorption peak(CO＝) was enhanced significantly. The C1,C2 and C3 spectra of C1s in the XPS spectrum were all greatly changed,and the C4(O-C＝O) energy spectrum was fitted. 2) The pore structure of the cross-linked CNF aerogels changed from the original irregularly shaped pores to relatively regular columnar pores. With the increase of BTCA content,the specific surface area and total pore volume gradually decreased. When the m(CNF)/m(BTCA) was 10/1,the specific surface area and total pore volume of CNF aerogels were reduced from 62.8 m²·g^-1 and 0.21 cm³·g^-1 to 35.5 m²·g^-1 and 0.098 cm³·g^-1,respectively,reduced by nearly half. When the m(CNF)/m(BTCA) reached 10/4,the structure of the aerogel became loose and appeared the excessive esterification phenomenon. 3) The density of pure CNF aerogels was only 5.76 mg·cm^-3, and its compression rate was up to 62.4% under 100 g load while the compression rate was only 30%. With the increase of BTCA content, both the density and the compressive recovery rate of aerogel were gradually increased, while the compression rate decreased gradually. When the m(CNF)/m(BTCA) was 10/1,the aerogel was still with the low density(7.67 mg·cm^-3) and the high compression rate(56.8%) while its compression resilience rate increased significantly(80.8%); When the m(CNF)/m(BTCA) reached to 10/4,the density of the aerogel increased to 9.54 mg·cm^-3, and its compression rate(reduced to 34%) and resilient rate(increased to 95%) were both changed significantly.[Conclusion] The results confirmed that the addition of BTCA made the CNF aerogels internal forming covalent bonds cross-linked structure,and had a significant effect on the internal pore structure and physical mechanicals performance. The greater mass ratio of BTCA and CNF,the density of aerogel was greater and the pore structure was more compact,only when the mass ratio of BTCA and CNF was within a certain range,which could improve the deformation resistance and deformation recovery ability of CNF aerogel at the same time to keep its good flexibility,and improve its application value.

[Objective] Hydroxytyrosol (HT), belongs to polyphenolic compounds, was widely distributed in olive fruit. Its nitration process is very important for the field of forest products processing industry. Since the traditional method with mixture of concentrated sulfuric acid and nitric acid was easy to make phenolic compound oxidation, and is not an environmentally friendly process. It is thus imperative to find a new fast way to make it nitration, unveiling the product chemical structure by classic multiple spectroscopies in the meantime.[Method] By means of being mixed with NaNO₂ under the condition of weak acid and room temperature, hydroxytyrosol was nitrated quickly. The nitro product was characterized by Uv-vis, FTIR, HPLC-MS, ¹HNMR and ¹³CNMR.[Result] It was observed that this reaction can be finished in 10 min with pH 3.8 (HAC-NaAC butter solution), achieving yield conversion 99.5%. Also, the maximum adsorption wavelengths of nitro-hydroxytyrosol were 245, 296 and 346 nm by Uv-vis spectrophotometer. Phenolic hydroxyl (wavenumber 3 359 cm^-1) of hydroxytyrosol as a reactant in the reaction process did not change, and nitro group (wavenumber 1 557 and 1 405 cm^-1) was introduced into hydroxytyrosol by the results of FTIR. The chemical structure of reaction product was further confirmed by HPLC-MS, ¹HNMR and ¹³CNMR, giving rise to a MW 199 and nitro group linked into para-position of phenolic hydroxyl in hydroxytyrosol.[Conclusion] By means of mild operation conditions (room temperature, pH 3.8 and 10 min), mixing with NaNO₂ as a cheap and accessible industrial raw material, hydroxytyrosol is very easy to get nitrated quickly and the nitro group in the product single-located in para-position of phenolic hydroxyl. These will provide a new path for nitro-phenol preparation to replace a traditional method using mixed strong acids, being of an importance.

[Objective] Effects of supercritical carbon dioxide extraction sterol from Korean pine needles were investigated, and the related kinetics and thermodynamics were evaluated, the result could provide theoretical reference for the extraction of effective components from plants with supercritical carbon dioxide.[Method] With the yield of sterol as index, based on the single factor experiment result, the effects of extraction pressure and extraction time on the extraction of sterol were discussed, and the extraction process was fitting and verified.[Result] The optimum extraction process was as follows:the particles sizes of pine needles were 80 meshes, extraction pressure was 25 MPa, carbon dioxide flow was 20 L·h^-1 and extraction temperature was 60℃, and the yield of sterol was (40.00±1.23) mg·(100 g) ^-1 under the optimum conditions. The kinetic analysis indicated that ExpDec1 model (R² ≥ 0.958 4) was the best one to fit the extraction course when the extraction pressure was 10, 15 and 25 MPa respectively. While the Logistic model (R²=0.996 8) was the best when the extraction pressure was 20 MPa. The verification experimental result showed that the fitting degree range between the predicted values of the best models and the measured values were 0.936 4-0.986 0.[Conclusion] The effective diffusivity coefficient value of supercritical carbon dioxide extraction sterol from pine needles was enhanced concomitantly with increasing value of extraction pressure, while reduced with extraction time increased. The variety of free energy indicated that the mass transfer process of the supercritical carbon dioxide extraction sterol was a spontaneous process.

[Objective] In order to detect the tiny defects of the edges of the bamboo slices, micro amplitude vibration of ultrasonic motor was utilized. The relationships between the micro amplitude vibration parameters of the ultrasonic motor and the size of the bamboo slices were studied. The device was designed to detect the change of the edge size of bamboo slices within 100 microns. It provides the theoretical basis for the on-line rapid detection of the production process.[Method] Using the converse piezoelectric effect of piezoelectric ceramics, elliptical motion in the stator of an ultrasonic motor drives the bamboo movement. The driving point is the edge of the bamboo slices. Under the normal pressure, sliding friction and wave number of different ultrasonic motors with fixed driving frequency of ultrasonic motor, analysis of the motion velocity of bamboo slices and the motion of the stator particle of the ultrasonic motor was analyzed by the stator kinetic equation. The movement of bamboo slices was analyzed by microscopic observation of the micromorphology of the bamboo slices.[Result] 1) The number of wave peaks of an ultrasonic motor driving bamboo is proportional to the driving force produced by an ultrasonic motor. With the change of the edge size of the bamboo slices, there is a gap between some stator driving particles and the bamboo slices when the bamboo slices are in contact with the stator. The number of wave peaks in a certain time point is reduced,Resulting in a decline in the speed of the bamboo motion. The number of wave peaks which drive the bamboo slices is reduced, which leads to the decline of the speed of the bamboo motion. 2) The normal pressure produced by the bamboo slices is evenly distributed on the wave peak driving point produced by the ultrasonic motor. When the size of the edge of the bamboo strip is reduced, the normal pressure is reduced. The driving force decreases, which reduces the speed of the bamboo motion. 3) Ultrasonic vibration produced by the stator of an ultrasonic motor produces ultrasonic friction reduction effect. The speed of the bamboo motion is reduces with the reduction of normal pressure. 4) Bamboo slices with error value from 0 to 50 microns were detected using the device for detecting the edge of bamboo. The relationship between the average speed of bamboo slices and the degree of bamboo defect is proportional. 5) When single bamboo was measured many times, its velocity fluctuated greatly. There are two reasons for the speed fluctuation. Firstly, the elastic modulus of different parts of bamboo is different, which leads to the change of the output force. Secondly, the micro morphology of the same piece of bamboo is very different. Under the microscope, the surface of the qualified bamboo slices has a micron level lack of edge phenomenon, which leads to the uneven contact surface of the bamboo edge driven by the ultrasonic motor. Therefore, the contact condition of the ultrasonic motor and the bamboo is changed. A change in the movement speed of bamboo slices caused by the change of contact surface condition.[Conclusion] The velocity of bamboo motion is proportional to the number of wave peaks of the ultrasonic motor that drive bamboo. The velocity of bamboo motion is reduced by the normal vibration of the ultrasonic motor. The increase of the pressure between the bamboo slices and the ultrasonic motor can increase the speed of the motion of the bamboo slices. The detection accuracy of the device for testing the lacing of bamboo slices is 48 microns. By measuring its speed, devices can distinguish the change of the defect size of the bamboo more than 48 microns. The size of bamboo slices cannot be measured accurately because of the large change in the size of the bamboo slice boundary size within the micron range.

Archidendron clypearia is a traditional Chinese medicinal tree species, it has widely been used in folk for a long history, and the researches and applications in the modern medicine field are more and more extensive. This paper briefly introduced the Latin names and taxonomy evolution, morphological characteristics, life habits and natural distribution of the tree species. The research progress and current status of its medicine, resources and cultivation were reviewed, the problems and solutions for its current research and applications were pointed out, and the prospect of its development and utilization was also prospected. Up to now, researches on A.clypearia at home and abroad are mainly concentrated in the aspects such as medicinal materials identification, chemical constituents, pharmacology and pharmacodynamics, clinical curative effects, as well as its pharmaceutical preparations and quality control of them. Its roots, twigs, leaves and fruits can all be used for medicine, which has obvious effects of clearing away heat and detoxification, cooling blood and detumescence, eliminating rheumatism and astringing sores, etc. Its major chemical compounds include flavonoids, catechols, tannides, which have been successfully purified and identified in more than forty chemical constituents, and the effective medicinal constituents are mainly Gallic acid, quercetin and quercitrin. "Zheng Wei Pian" is a kind of compound medicine of it, while "Houerhuan antiphlogistic tablets", "Houerhuan antiphlogistic capsule", and "Houerhuan antiphlogistic particles" are all single ingredient medicines made from it, all of them have been clinically verified effective in treatment and have been popularized in clinical use. These medicines can be clinically used for not only exclusive but also adjuvant treatments of such diseases as upper respiratory tract infection, acute pharyngitis, acute tonsillitis, acute gastroenteritis and so on, both of the two kind of treatments have significant effect. More and more medicinal materials of A. clypearia are demanded, but almost all of the commercial medicinal materials are still harvested from wild resources, excessive harvest has made a sharp decrease in wild resources and caused the serious supply shortage of the raw medicinal materials. Present cultivation researches on A. clypearia, including those on seed storage, seed germination and seedling cultivation technology, as well as those on cutting propagation and tissue culture techniques, are still at the preliminary status, it needs further technical improvement and perfection before turning the present cultivation technologies into practical technologies and being widely used in seedling production. Studies show that A. clypearia not only has a bright future in use of drugs for human health, but also has giant development potential in such areas as biological pesticide, landscaping, wood processing and utilization, and forestry economy and so on, it is of great significance to develop and utilize A. clypearia all around. In conclusion, it is imperative to protect the existing wild resources of A. clypearia, to improve and perfect its cultivation technology at present The future development directions are to carry out multi-field cooperation, common research and comprehensive exploitation and utilization of the tree species. It is the focus of future research directions to breed valuable varieties to meet the future needs and to improve the comprehensive utilization technology of the whole tree; and it is the ultimate development goal to establish large scale production bases of A. clypearia, to carry out multi-objective management and industrial utilization of it, and to make it fully benefit human society.

[Objective] This paper was aimed to help tourists to select the best time to visit Beijing Fragrant Hills Park and to provide a theoretical basis for park greenbelt management and landscape setting.[Method] The measurements were continuously taken in 5 recreation points with different vegetation types in Fragrant Hills Park during a 10-day period in summer. The square outside the park was chosen as the control for comparisons. We analyzed the regularity of diurnal variation of every factor and statistically compared the difference and correlation of various ecological factors among the monitoring points, through analyzing micro climate changes, PM₁₀ and PM_2.5 mass concentration variation, differences of human comfort index, negative air ions concentration and noise pollution at the 6 monitoring sites.[Result] In the Fragrant Hills Park, daily temperature and relative air humidity showed single peak type curves. Relative air humidity increased by 6%, and air temperature decreased 1.7℃ on average. The longest duration with human comfort index reaching level Ⅱ were 8.5 hours. The PM₁₀,PM_2.5 mass concentration variation showed double peaks type curve, of which the values were high in morning and evening while low in afternoon. The average daily purification rates of every recreation points for PM_2.5 reached 27.6% and for PM₁₀ reached 25.9%, respectively; Moreover, the two kinds of particles had significant positive correlation (P<0.01); The concentration variations of temperature and humidity variation showed significant negative correlation (P<0.05) and positive correlation (P<0.01); negative air ions concentration showed peak and valley alternately with changing regularity, 3 peaks respectively occurred in the morning, noon and evening. Daily average index in the park was 795 ion·cm^-3, 2.43 times of the index outside the park, displaying significant negative correlation with PM₁₀,PM_2.5 concentration (P<0.01), significant negative correlation with temperature (P<0.05), and significant positive correlation with humidity (P<0.01). Each recreation point reached mild or moderate pollution levels at around 6:00 and 20:00-21:00, through the CI index analysis. Average index of noise in the park reached 40.3 dB and the average noise reduction rate reached 21.8%, showing significant negative correlation with plant canopy density (P<0.05). Meanwhile, plant canopy density showed significant positive correlation with negative air ions concentration (P<0.01) and negative correlation with PM₁₀ and PM_2.5 mass concentration (P<0.01).[Conclusion]We found that differences exist among various vegetation types in the Fragrant Hills Park in the ecological functions of increasing humidity, cooling temperature, antipollution, noise reduction etc., the eco-environmental effect of Cotinus coggygria mixed forest was the highest while that of the grass lawn was the lowest, the reasonable recreation periods of Beijing Fragrant Hills Park in Summer were 7:00-11:00 and 17:00-20:00.

[Objective]In order to provide theoretical basis for protection and rational utilization of the plant resources in Guniujiang National Nature Reserve of Anhui Province.[Method] In order to explore the altitudinal gradient of plant communities and plant species diversity, we sampled the vegetation on north slope of Guniujiang National Nature Reserve by sampling plots.[Result]The Spermatophyte composition was relatively rich and a total of 1414 species belonging to 145 families and 687 genera were found in the reserve. The floristic origin was ancient, geographical components were multiform and the distribution types were different. The number of genera consisting of single species or 2-5 species was accounted for 94.32% of the total number of genera. The temperate elements were more than the subtropical ones (359/234), indicating a transition of the floristic affinity from subtropics to temperate. The vertical vegetation spectrum was evergreen broad-leaved forest (below 800 m a.s.l.), mixed deciduous and evergreen broad-leaved forest (800-1 100 m a.s.l.), deciduous forest (1 100-1 300 m a.s.l.), mixed coniferous and deciduous forest (1 300-1 500 m a.s.l.), and coniferous forest (above 1 500 m a.s.l.). The vegetation types showed that Guniujiang National Nature Reserve was in the transition zone form subtropical evergreen broad-leaved forest to warm temperate deciduous forest. The species richness and diversity index showed an declined trend with increase of altitude. The species richness on the nouthern slope was always higher than on the southern, while the terrain is steeper and the soil layers even thinner on the southern slope base as a consequence of the glaciation impacts.[Conclusion] The species diversity showed a pattern of "Mid-altitude bulge" with change of altitude, which means that biodiversity is higher at intermediate altitudes. There were evident differences in community structure of trees among different topographies, and topographic heterogeneity had contribution to maintaining species diversity. The conclusion presented an important basis for protecting ecosystem diversity and developing ecological monitoring in Guniujiang National Nature Reserve. Meanwhile, the study also provided guidance to choose different species combinations in different topographies when restoring mountain forest and contingent planning for multi-dimensional agriculture and ecotourism. Moreover, it was also an important tool to be applied in promoting ecosystem services and ecological security in the Huangshan Mountains.

[Objective] To reveal seed germination characteristics of the rare and endangered plant Garcinia paucinervis and its suitable conditions of seedling growth, the endangered factors of G. paucinervis were analyzed during seed germination, which provided theoretical support for its protection, introduction, domestication and efficient seedling propagation.[Method] The germination conditions of G. paucinervis seeds were discussed in terms of the ecological factors that may affect their germination (e.g. temperature, light, soil moisture, substrate, burial depth and different populations) and the biological characteristics (e.g. seed coat and seed weight). The germination conditions of G. paucinervis seeds were discussed and the endangered mechanism was predicted.[Result] The germination processes of G. paucinervis seeds were slow and irregular. Both endocarp and seed coats delayed seed germination, nevertheless, they had no effect on final germination percentage (GP). The seed coat had no inhibitory effect on germination. The seeds could germinate at 25℃, 32℃, and room temperature, and the germination process and growth rate could be obviously accelerated at 32℃, but the seeds did not germinate at 18℃ and 37℃. The seeds were able to germinate under the condition of continuous light, continuous darkness and periodic light. The germination speed was the fastest and the germination was the most uniform under the periodic light, but there was no significant difference in GP under 3 light conditions. Thus, the G. paucinervis seed was the non-hotoblastic seed. The GP was the highest when seeds were sown in the sand and peat soil. The seeds germinated more slowly in clayey loam or limestone soil, where their GP was lower. The aboveground and underground parts of seedlings in peat soil and vermiculite grew better. The limestone soil with 40%~60% moisture content was more suitable for germination, and Germination time lag (GTL) was longer under 80% moisture content, but the seed could not germinate under 20% moisture content. In the same burial depth, compared with limestone soil as substrate, the germination energy (GE) and the germination percentage (GP) of seeds sowed in sand was higher. With the increase of burial depth, both GE and GP decreased, and the germination speed was the fastest and the germination was the most uniform with the treatment of sand as substrate and 0.5 cm burial depth. Among the seeds of Nonggang (NG), Anning (AN) and Hurun (HR) populations, the GP of HR population was the lowest and the germination speed of HR population was the slowest. The seedlings of NG population were slender, and the seedlings of HR population were stouter and shorter, and whose root system was more developed. There were no significant differences in most of germination parameters and seedling growth among 3 weight level seeds (<4 g,4~5 g and >5 g), so seed weight had no significant effect on seed germination and seedling growth. The seeds germinated had been removed shoot and radicle then sowed again, which could still germinate, so G. paucinervis seeds had the ability of regeneration.[Conclusion] The G. paucinervis seeds have dormancy. The temperature range of its seed germination is narrow and the seed germination is sensitive to substrate ventilation and water permeability. The regeneration capacity of seeds can prevent seed's failure to seedling and strengthen their viability. However, the slow germination speed and growth of seedlings are not conducive to the rapid occupation of population space resources, and seed germination has a higher requirement for soil permeability and moisture, which may be important reasons for the decline of their populations and their endangerment.

[Objective]In this paper, the unmanned aerial vehicle (UAV) remote sensing technique was used to monitor mousehole density by great gerbil (Rhombomys opimus) in the southern margin of the Gurbantunggut desert forest. The purpose was to explore the best interpretation method of aerial imagery of the rat-holes and to provide a solution for the rapid interpretation of the data of the low altitude remote sensing aerial rodent damage.[Method]Fixed-wing UAV equipped with a digital cameras sensor was used to obtain 2.4 cm resolution aerial images, and TDOM imagery was acquired after pre-processing. The TDOM images were interpreted by artificial visual interpretation, supervised classification and object-oriented classification method, respectively, by which we extracted the spatial distribution information of the rodent cave, and then analyzed and evaluated the applicability and classification accuracy of each method in the rodent extraction in desert forest.[Result]By comparing the three methods of interpretation, it was found that the accuracy of artificial visual interpretation was high, but workload was too heavy for a large scale image; the classification accuracy of the supervised classification method was low and it was not applicable; and the object-oriented classification method not only had high precision, the classification results were consistent with visual interpretation method, but also improved the processing speed of big data.[Conclusion]This paper validated the availability of the UAV technique for dynamically monitoring rodent pests in desert forest, and laid a critical foundation for further study.