Objective: The sensitivity of landscape pattern indices to color patterns of scenic forests was studied. And indices capable of characterizing landscape color patterns were selected, aiming to provide experimental supports and theoretical basis for studies of visual quality of colorful landscape forests. Method: Photos of scenic forest dominated by Cotinus coggygria var. cinerea taken in autumn were used in the research. An application for color quantification and classification was implemented using Python program, effective for data preparation in batch. Pre-selected indices were calculated in Fragstats software, and then hierarchical cluster analysis was performed in SPSS software. Sensitivity of indices to landscape color pattern changes related to color classification and viewing distance was calculated and used for indices ranking. Under the principles of covering most clusters and reducing information redundancy, indices were selected after performing independence tests and information overlaps check. Result: Seven indices, namely, number of patches, largest patch index, mean patch area, patch richness, mean nearest neighbor distance, mean perimeter/area ratio and modified Simpson's diversity index, which are sensitive to color classification and viewing distance, were selected from 24 pre-selected ones. They could be used to quantitatively characterize color patterns of scenic forests. Conclusion: The semi-automated procedures for color classification, which requires operator intervention during analytic process, simplify operations from color classification to index calculation, reduces time for data preprocessing and enhances the stability of the result. The proposed method for selecting color pattern indices based on sensitivity ranks, combined with independence test and information overlaps check, reduces errors caused by subjective selectior indices. And indices selected are effective to distinguish changes of color pattern caused by color classification and viewing distance, and possible to objectively and quantitatively analyze visual quality of scenic forest.

Objective: The effects of different management methods of burned wood on soil respiration and its composition in the burned area of Larix gmelinii forest in the Daxing'anling permafrost region were investigated to understand the relations of soil respiration to soil temperature and moisture content, and to provide a theoretical basis for the restoration and reconstruction of the burned forest. Method: The burned area of L. gmelinii forest in 2009 in the cold temperate zone permafrost region were investigated using LI-8100 soil respiration measurement system to detect soil respiration rate in 2016 and 2017, while the seasonal variation of soil temperature and moisture content were also measured at the same time. The effects of soil temperature and moisture content changes on soil respiration rate were investigated and made a comparison among the sample plots of burned wood management (2009C for clear-cutting of burned wood, 2009S for selective cutting, and 2009N for no-cutting) and the control plots (2009CK for no-fire and no-cutting). Result: During the observation period, soil respiration rate (R_S) and soil heterotrophic respiration rate (R_H) in four models of sample plots were ranked as 2009S > 2009N > 2009CK > 2009C. In 2016, soil autotrophic respiration rate (R_A) was ranked from large to small as 2009N > 2009S > 2009CK > 2009C. In 2017, it was 2009CK > 2009N > 2009S > 2009C. Four types of sample plots displayed that the soil heterotrophic respiration contribution ratio (C_H) was larger than the soil autotrophic respiration contribution ratio (C_A). The greatest C_A was in the control plot (23.75%), while the minimum was in 2009C (16.04%), with a rank of 2009CK > 2009N > 2009S > 2009C. Soil respiration and its components were positively correlated with T₁₀ in four sample plots (P < 0.01). Fire interference reduced the sensitivity coefficient of soil respiration and its components to the temperature. Conclusion: In the L. gmelinii forest in the Daxing'anling permafrost region, burning increased soil respiration rate, and soil heterotrophic respiration rate, which were further increased by selective cutting. However, all the increases were not significant (P > 0.05). Cutting the burned wood restricted the soil respiration rate and its components, and the soil autotrophic respiration rate of the 2009C significantly decreased from 2009CK (P < 0.05). Burning interference also diminished the contribution ratio of soil autotrophic respiration rate and cutting of the burned wood further reduced the C_A, the higher the cutting intensity, the greater the decrease. The soil respiration and its components in the four types of sample plots revealed strongly significant positive correlation with 10 cm soil temperature (P < 0.01). The sensitivity of soil respiration and its components to soil temperature in the three sample plots of burned wood was lower than that in the control plots. There were no significant positive relations between soil respiration with its components and the 10 cm soil moisture content in the burned area of L. gmelinii forest permafrost region (P > 0.05).

Objective: This paper aims to explore the distribution characteristics of organic acids in the soil from different stands in Guizhou Baili Rhododendron National Forest Park, in order to provide technical strategies for the soil management of wild rhododendron stand. Method: The topsoil of R. delavayi evergreen mixed forest, R. irroratum evergreen mixed forest, R. agastum evergreen mixed forest, evergreen broad-leaved mixed forest, and deciduous broad-leaved mixed forest were collected, and the contents of organic acids (oxalic acid, tartaric acid, formic acid, malic acid, lactic acid, acetic acid, citric acid, succinic acid) were determined by high performance liquid chromatography (HPLC). Result: The distribution of total content of organic acids in different stand types was as follows: deciduous broad-leaved mixed forest>R. irroratum evergreen mixed forest>R. delavayi evergreen mixed forest > evergreen broad-leaved mixed forest>R. agastum evergreen mixed forest; There were significant differences in soil organic acids among different stand types. The order of organic acid contents was oxalic acid > tartaric acid > citric acid > malic acid > lactic acid > acetic acid > formic acid > succinic acid. Oxalic acid is the dominant acid, and the contents of acetic acid, formic acid and succinic acid were relatively low; There was a negative correlation between soil organic acids and pH, among which tartaric acid was highly significantly negatively correlated with pH, and citric acid was significantly negatively correlated with pH; The clustering results showed that the deciduous broad-leaved mixed forest was obviously different from other stand types, and the oxalic acid content was the highest. Conclusion: The distribution of soil organic acids in different stand types is affected by dominant species. The content of soil organic acid in deciduous broad-leaved mixed forest is much higher than that of evergreen broad-leaved mixed forest and rhododendron evergreen mixed forest in Baili Rhododendron National Forest Park. The distribution characteristics of organic acids in forest soils should be the focus of stand management.

Objective: This study was conducted to reveal the main free and glycosylated aroma compounds of different Osmanthus fragrans cultivars.The results could provide theoretical foundation for industrial application of O. fragrans. Method: The petals of three widely cultivated O. fragrans cultivars, 'Wan Yingui', 'Huangchuan Jingui' and 'Chenghong Dangui', were selected as materials. The petals at the unexpanded period, initial blossoming period, full blossoming period and late blossoming period were collected and extracted with organic solvent, Amberlite XAD-2 resin adsorption and elution separation combined with glucosidase hydrolysis were conducted for extracting free and glycosylated aroma compounds. The aroma compounds were then identified and quantitatively analyzed by gas chromatography-mass spectrometry (GC-MS). Result: 1) A total of 25 free and 28 glycosylated aroma compounds were determined in the three cultivars, mainly including monoterpenes, monoterpene alcohols, monoterpene ketones, monoterpene oxides, aromatic compounds, esters, alkanes and others. Massive monoterpenes tended to connect with sugars after oxidation and hydroxylation, forming colorless and odorless glycosides. Thus, the content of glycosylated aroma compounds was significantly higher than that of the free aroma compounds. 2) The free and glycosylated aroma compounds continued to accumulate during the blossoming period progress. The content of free aroma compounds reached the maximum at the full blossoming stage, while the content of glycosides reached the maximum at the end of flowering. 3) The aroma components of the three cultivars were similar, but the content was significantly different. The free aroma compounds of 'Wan Yingui' and 'Huangchuan Jingui' were mainly trans-β-ionone, γ-decalactone and 8-hydroxylinalool, while the glycosides were mainly 4-hydroxy-phenyl alcohol, 4-hydroxy-β-ionone, 3-oxo-α-ionol. The free aroma compounds of 'Chenghong Dangui' dominantly contained γ-decalactone, linalool oxides, 4-hydroxy-phenyl alcohol, while the glycosides were mainly 4-hydroxyphenyl alcohol, 3-oxo-α-ionol and 8-hydroxylinalool. Based on the total contents of aroma compounds, linalool and its derivatives dominated the aroma compounds in 'Chenghong Dangui', while ionone and its derivatives took major proportion in 'Wan Yingui' and 'Huangchuan Jingui'. The cleavage of carotenoids was the key factor for causing the differences among cultivars. 4) Among all the free and glycosylated aroma compounds, γ-decalactone, linalool, ionone and their derivatives were important aromatic compounds with floral and fruitly characteristics. Conclusion: Our results demonstrate that a large amount of free and glycosylated monoterpenes and their derivatives, esters, aromatic compounds are widely distributed in Osmanthus fragrans flowers with significant differences among cultivars. Those compounds can be extracted by organic solvent and hydrolase to promote the aroma quality of industrial products.

Objective: Juniperus sabina is an important tree species for sand-fixing and soil-holding in rocky mountain slopes, river valleys and sand-covered hilly areas in Europe, Asia and America, which is of great significance for maintaining the stability of ecological environment. The paper tries to identify the dominant environmental variables that limit the distribution of J. sabina and to predict its suitable distribution area, in order to provide a theoretical basis for the administration and restoration of the species. Method: The geographic information of 267 existing populations and environmental variables(climate, elevation), were analyzed using three models of MaxEnt, BioClim and DoMain to simulate the potential suitable distribution areas for the species. The three models were compared and analyzed with the area under curve(AUC value) of receiver operating characteristic(ROC) and Kappa value. The potential geographical distribution patterns of the Last Glacial Maximum(LGM), the Mid-Holocene(MID), Current and Future(2070) based on the MaxEnt modelling are compared and the environmental variables that restrict the geographical distribution of J. sabina are discussed. Result: 1) The percent contribution of the environmental variables, permutation importance and jackknife method showed that the geographical distribution of J. sabina was mainly affected by annual mean temperature, elevation and temperature seasonality. 2) The present suitable habitat area of J. sabina in Eurasia based on the MaxEnt model with climate variable simulation is 663.115×10³ km², concentrated in the range of 30°—50°N, with mountainous sites as the main suitable areas. 3) The suitable habitat areas of J. sabina in different geological historical periods indicated that Asia is the main distribution area, the suitable areas of Asia in the LGM, MID and Current period accounted for 86.9%, 87.0%, and 57.8%, respectively. In the Future periods, the suitable areas of Asia occupied with 84.1% under 2070(RCP2.6) and 79.2% under 2070(RCP8.5). From the Last Glacial Maximum, Current to the Future, the suitable habitat area increased first and followed by a decrease, and the distribution center tended to migration from north to south and then to further north. Conclusion: The geographical distribution of J. sabina was not only affected by climate and environmental variables(including temperature and precipitation), but also related to elevation. The distribution area is in accordance with the characteristics of Cupressaceae distribution zone. This study provides an important basis for the management and restoration, rehabilitation of the germplasm resources of J. sabina.

Objective: To reveal genetic diversity and patterns of geographic variation of leaf phenotypic traits in and among different populations of Populus cathayana so as to lay a foundation for further analysis of genetic mechanism, and for collection, conservation and improvement of P. cathayana germplasm resources. Method: A total of 34 P. cathayana populations from the main distribution areas in China were sampled by collecting 1-2 years old shoots. The shoots were cutting-propagated in greenhouse and transplanted into nursery, the transplanted plants were topped in spring in the following year, the 7th, 8th and 9th new leaves below the stem tip were collected in July and 14 phenotypic traits(leaf morphological traits, leaf colour and SPAD) were measured. Variance analysis, correlation analysis and cluster analysis were conducted. Result: There were significant differences in the 14 traits among and within populations(P < 0.01), indicating that the genetic variation of leaf in P. cathayana was abundant. The average phenotypic population differentiation coefficient was 55.771% among populations, indicating the main source of variation was from among the populations. The average coefficient of variation for phenotypic traits was 20.562%, the largest coefficient of variation was relative length of petiole while the chlorophyll SPAD value was the smallest. The average coefficient of variation of phenotypic traits in each population was 12.852%, population Badi (No. 31) in Inner Mongolia Autonomous Region had the most abundant variation while population Longquan (No. 11) in Hebei province had the smallest variation and the highest stability of phenotypic traits. There was significant or extremely significant correlation between leaf phenotypic traits and geographical meteorological factors, only leaf color had no significant correlation with other leaf traits, reflecting its relatively independent inheritance. The 34 populations were divided into 4 groups, they are large leaf with long petiole, medium leaf, narrow leaf with short petiole and small leaf. The populations can be divided into three distribution regions according to the distribution of the taxa and the characteristics of Chinese topography: the northern margin of North China Plain in the east of Taihang Mountains(region 1), the Loess Plateau between Taihang Mountains and Liupan Mountains-Qinling Mountains(region 2), and the surrounding area of Qinghai-Tibet Plateau(region 3). The narrow leaf with short petiole accounted for 57.14% in the region 1, medium-sized leaf accounted for 66.67% in the region 2, and the small leaf accounted for the largest proportion 62.5% in the region 3. Conclusion: The genetic variation of leaf traits in P. cathayana was abundant, population Lanqikalun(No. 17) in Hebei province, Banjieta(No. 30) and Badi(No. 31) in Inner Mongolia Autonomous Region had rich diversity and were the priority populations for diversity protection and germplasm conservation. There was a strong correlation between leaf phenotypic traits and geographical meteorological factors, and the patterns of geographic variation of leaf of P. cathayana mainly related to altitude.

Objective: The forest volume estimation model was constructed by using random forest algorithm based on the forest height parameters and crown density extracted from airborne LiDAR point cloud data, combined with stratified ground sample plot survey data. The potential of airborne LiDAR data in forest volume inversion was analyzed, so as to provide method basis for efficient and accurate estimation of forest volume. Method: The ground sample circle with a diameter of 30 m was set up, and the point cloud data of discrete sample circle was used as the data source. After data calibration and other preprocessing, the forest height parameters(maximum height, mean height) and crown density were extracted by LiDAR360 software. The research data were categorized as training and test datasets. The random forest algorithm was used for modeling using only height parameters as well as a combination of height parameters and crown density, the results thus obtained were analyzed. The VSURF package in R software was used to select modeling variables, and the selected variables were evaluated. Result: In the test phase, when using height parameters alone, modeling accuracy of R²=0.75, RMSE=40.07 m³·hm^-2, MAE=29.21 m³·hm^-2, and MRE=49.40% were obtained, respectively. In contrast, when combining height parameters with crown density, modeling accuracy of R²=0.79, RMSE=36.23 m³·hm^-2, MAE=26.16 m³·hm^-2, and MRE=38.35% were obtained, respectively. This indicated that crown density was an important parameter and that using height parameters alone was insufficient for estimating forest volumes via airborne LiDAR point cloud data. Using variable selection, 24 effective parameters were reduced to 7. Although R² remained relatively unchanged, the RMSE and rRMSE increased from 36.23 m³·hm^-2 to 36.50 m³·hm^-2, and from 31.92% to 32.97%, respectively. Whereas MAE and MRE decreased from 26.16 m³·hm^-2 to 26.08 m³·hm^-2, and from 38.35% to 38.05%, respectively. Conclusion: Airborne LiDAR point cloud data could extract not only the vertical structure information of forest(height variable), but also the horizontal information of forest(crown density), which has the ability to extract forest three-dimensional structure parameters. Moreover, crown density variables could be employed to significantly improve the accuracy of estimating forest volumes using the random forest method. As variable selection reduces modeling accuracy to a certain extent, it was recommended that all the variables could be used for modeling estimation when high accuracy is required. However, for large data volumes, variable selection is still preferable. This approach of estimating forest volume using airborne LiDAR data is significantly superior to the approach utilizing optical data, thus, the proposed method serves as a basis for high-precision estimation and meets the requirements of rapid inversion of forest volume in large areas.

Objective: The purpose of this study is to analyze the functions of the exocyst subunit CcExo70 in poplar canker fungus, Cytospora chrysosperma, including its roles in fungal growth, development and pathogenicity. This study would provide a scientific basis for further understanding the pathogenic mechanism and establishing the disease control strategies. Method: 1) PCR amplification was used to clone the CcExo70 from the C. chrysosperma. 2) The amino acid sequences were characterized by bioinformatics methods, and a phylogenetic tree of its homologous genes was constructed. 3) The knockout mutants and complementary strains of CcExo70 were obtained by using the PEG-mediated transformation method. 4) The effects of knockout of CcExo70 gene on growth and development, morphogenesis, and H₂O₂ stress response were analyzed on PDA plates or in liquid PDB, and the effect of CcExo70 gene on pathogenicity was tested with one-year-old Populus×euramericana. 5) The calcofluor white(CFW), DAB(3, 3'-diaminobenzidine), and FM4-64 were used to investigate the chitin deposition, reactive oxygen species accumulation and endocytosis of each strain. 6) The comparative proteome analyses were performed to screen the putative secreted proteins regulated by CcExo70. Result: 1) The CcExo70 gene was cloned from the genomic DNA of C. chrysosperma. The full length of the gene was 1 992 bp, including one intron encoding 636 amino acids. 2) Phylogenetic analysis and sequence alignment showed that CcExo70 was highly conserved with Exo70 homologs from other pathogenic fungi. 3) Two CcExo70 deletion mutants (ΔCcExo70-8 and ΔCcExo70-9) were screened by using the split-marker method named, and the complemented strain (ΔCcExo70/C) was obtained. 4) Phenotypic analyses showed that deletion mutants of CcExo70 displayed obvious defects in fungal growth, morphogenesis, oxidative stress response and pathogenicity compared to the wild-type and complemented strains. 5) CFW staining showed that there was obvious chitin deposition at the mycelial tip of wild-type and compensatory strains, while there was no obvious chitin deposition at the mycelial tip of knockout mutants, but septa were increased. Additionally, confocal microscopy showed that endocytosis in CcExo70 deletion mutants was significantly delayed compared to the wild-type and complemented strains. 6) Proteome sequencing analysis showed that the abundances of eight candidate secreted proteins were significantly reduced (over 50%) in culture filtrates of the CcExo70 deletion mutant compared to that in wild type by using proteomics analysis. Additionally, four of them (CcSP2k, CcSP3, CcSP6, CcSP7) were dramatically enriched in the culture filtrates compared to the corresponding intracellular protein profiles including 1 putative effector (CcSP2) and 2 glucoside hydrolases (CcSP6, CcSP7), indicating the secretion of these candidate proteins was regulated by CcExo70. Conclusion: Collectively, these results suggest that the exocyst subunit gene CcExo70 is essential for the fungal growth, stress response, endocytosis and pathogenicity of C. chrysosperma.

Objective: Colletotrichum fructicola is a major epidemic and causes anthracnose of Camellia oleifera. This paper aims to study the biological functions of the vacuolar protein sorting Vps26 in C. fructicola to provide a theoretical basis for the prevention and control of oil-tea tree anthracnose, and also for further analysis of Vps26 action mechanism. Method: The over-lap method was used to construct the CfVPS26 gene knockout vector fragment which was transformed into the protoplast of C. fructicola by using PEG-mediated transformation method to obtain the mutant strain of ΔCfvps26. The PCR-amplified CfVPS26 gene-containing complement of the promoter was taken to construct a complementary vector. Then the complementary vector was transformed into the mutant protoplasts. The complemented strain was screened by fluorescence. The biological phenotypes, such as vegetative growth, appressorium formation, external environmental pressure, glycogen metabolism and pathogenicity, of the wild-type strain, mutant strain, and the complemented strain were measured. Result: The results showed that the mycelial growth rate of ΔCfvps26 was significantly lower than that of the wild type strain and the complemented strain. And the aerial hyphae were significantly decreased, and more sensitive to 200 μg·mL^-1 calcofluor white and 0.01% sodium dodecyl sulfate. Compared with the wild type and the complemented strain, the tolerance of the mutant strain ΔCfvps26 to dithiothreitol was enhanced. The conidia production and appressorium formation rate of CfVPS26 gene deletion mutant were significantly reduced, and glycogen metabolism was blocked. The mutant strain almost lost pathogenicity on the leaves of C. oleifera. Conclusion: This study reveals that the vacuolar sorting protein CfVps26 plays critical roles in growth and development, condiation, appressorium formation, tolerance to external stresses, glycogen metabolism and pathogenicity in C. fructicola on C. oleifera. These results provide potential target sites for the development of new fungicides against C. fructicola.

Objective: Corythucha ciliata(Hemiptera: Tingidae), an important invasive pest in China, mainly damages on Platanus plants. It has broken out in multiple regions of China. This research tries to explore the genetic differentiation among the geographic population of C.ciliata, and probe its spread path. Method: The sectional nucleotide sequences of COⅠ gene of 240 individuals from 12 geographic populations were determined. Based on their nucleotide sequences, the genetic differentiation, gene flow level, molecular variance, and population demographic history were analyzed by using DnaSP V6.12.03 and other analysis software. Result: There were 13 mutation sites and 9 haplotypes in the COⅠ gene among 12 geographic populations. Among them, 5 haplotypes were shared by all the geographic populations, and the haplotype H1 was an ancestor haplotype. Haplotype diversity index (H_d) of the total population was 0.584, and the H_d value among geographic populations ranged from 0 to 0.758. The fixed coefficient(F_ST) of the total population was 0.48, and the value between geographic populations ranged from-0.05 to 0.89, suggesting that the degree of differentiation between different populations of C. ciliata was obviously different. Gene flow value(N_m) was 0.55 within the total population and ranged from-85.25 to 47.58 between geographic populations, indicating that the degree of gene exchange was distinct difference among populations. The individual variation within the populations accounted for 52.19% of the total variation, while populations of C. ciliata from the Central China experienced a population expansion event. Conclusion: There are significant differentiation of genetic structures among different groups and different geographical populations of C.ciliata. The genetic differentiation of geographic populations primarily derives from variation of intraspecies. The genetic distance of the geographical populations is no significant association with geographical distance, and the geographical distance has no obvious effect on the gene flow of populations. Furthermore, we speculate that the insect spread from Shanghai as the center to other regions in China.

Objective: Andricus moriokae is an important pest that induces galls on oak. This study aimed to clarify the ultramorphology of the female A. moriokae, especially for the types, quantity, and distribution of sensilla on the compound eyes, mouthpart, antennae, legs and ovipositor. Method: The ultramorphology of female A. moriokae was observed under the scanning electron microscope. Result: It was found that the compound eyes of A. moriokae are composed of a number of ommatidia with conical sensilla. The antennae of female insects are composed of a scape, a pedicle and 11 flagellomeres. The scape is funne-shaped, and the pedicle is short and globular. The first three flagellomeres are long columnar, and the last one is a bullet-shaped. The rest flagellomeres are short columnar. There are 5 kinds of sensillum distributed on the antennae of the gall wasp, including sensilla trichodea, sensilla chaetica, sensilla basiconica, sensilla placodea and sensilla coeloconica, of which the number and distribution of sensilla trichodea are the most extensive. The sensilla placodea is particular in the flagellomeres 3-11, with long and wide shape and smooth surface. The mouthparts are developed with sensilla trichodea on the maxillary palps. The legs are fluted with sensilla chaetica and sensilla trichodea. The ovipositor bears sensilla trichodea, sensilla chaetica, sensilla basiconica, sensilla auricillica and sensilla volcanica. Conclusion: There are different types of sensilla distributed on the compound eyes, antennae, mouthpart, legs and ovipositor of the female of A. moriokae. The functions of all kinds of sensory organs are closely related to a series of physiological activities such as roosting, feeding and reproduction of A. moriokae. This study may provide a theoretical basis for the comprehensive control and utilization of A. moriokae.

Objective: Jujube is a fruit-borne tree with entomophilous flowers. This study aims to explore the adaptability of flower-visiting insects to biological characteristics of jujube flowers by analyzing the differences of visiting behaviors of visiting insects in different disturbed habitats, which is beneficial to protect pollinating insects in jujube garden and lays a foundation for improving the pollination rate of jujube. Method: Huping jujube in Xiaobai Township, Taigu County, Shanxi Province was selected as the research object. The stigma receptivity, pollen viability and nectar secretion of jujube flowers were determined by benzidine-hydrogen peroxide method, iodide-iodine kalium staining method and micro sampler method, respectively. The number and behavior of flower-visiting insects in high disturbance and low disturbance jujube orchards were investigated by the method of visual observation, net catching and sticky plate. The collected data was subjected to statistical analysis. Result: 1) The flowering stage of jujube can be divided into seven stages: bud cracking stage, initial opening stage, sepal flattening stage, petal stamen separation stage, petal flattening stage, petal drooping stage and stamen drooping stage. The whole flowering process was completed within 24 hours. Anthers dehiscence occured at about 12:00 at noon on the flowering day. Pollen vitality reaches its maximum around 13:00, which is 68.35%. The stigma became mature at 16:30, and has the strongest receptivity from 13:00 to 15:00 on the second day after the blooming. The stigma receptivity and pollen viability of jujube flower presented the trend that first increased and then decreased. 2) A total of 3 090 visiting insects of jujube flowers were collected in the two plots, belonging to 8 orders, 57 families and 90 species, including Hymenoptera, Diptera, Coleoptera, Lepidoptera, Thysanoptera, Hemiptera, Neuroptera and Psocoptera. Among them, Hymenoptera, Diptera, Hemiptera and Coleoptera had the most families, accounting for 33.33%, 19.30%, 15.79% and 14.04% of the total families, respectively. Diptera, Thysanoptera and Hymenoptera had the largest number of individuals, accounting for 36.47%, 24.72% and 18.71% of the total number of individuals, respectively. 3) There were 703 flower-visiting insects of 43 species in high disturbance plots and 2 387 flower-visiting insects of 85 species in low disturbance plots. The flower-visiting insects of Hymenoptera had largest species in the two plots. The individual number of Thysanoptera insects was significantly higher than that of other orders, and the dominant flower-visiting insects were flower-eating insects in high disturbance plot. The individual number of Diptera was significantly higher than that of other orders in low disturbance plot. The dominant flower-visiting insects were pollinators, and the pollinators in low disturbance plots were significantly more than those in high disturbance plots. 4) The nectar secretion time of jujube flower was 12 hours. The nectar secretion amount was the most at about 13:00, and the number of flower-visiting insects was the largest at 10:00-16:00 in low disturbance plot. The peak period of flower-visiting insects and the period of more nectar secretion in the low disturbance plots were consistent with the time when the pollen vitality and stigma receptivity of jujube flowers were the strongest. The nectar secretion was the most at 19:00-22:00, and the number of flower-visiting insects was the most at 7:00-10:00 in the high disturbance plot. Insects visit flowers occurred mostly in the early morning which was inconsistent with the time when the pollen vitality and stigma receptivity of jujube flowers were the strongest. Conclusion: The species and quantity of flower-visiting insects in low disturbance plots are more than those in high disturbance plots. The dominant flower-visiting insects in the high disturbance plots are flower-feeding insects, while the dominant flower-visiting insects in the low disturbance plots are pollinators, and the number of species and individuals of pollinators are significantly larger than those in the high disturbance plots.The flower-visiting insects in high and low disturbance plots are adapted to nectar secretion characteristics of jujube flowers.

Objective: In this paper, effects of poplar inter-species plantations on growth characteristics and resistance to defoliators were surveyed to explore the planting mode of poplar plantation with high quality, high resistance and high efficiency, so as to provide a theoretical basis for enriching and enhancing the economic and ecological value of poplar plantation. Method: In 2016, four dominant three-year-old poplar species (cultivar), namely Populus alba×P. berolinensis, P. simonii×P. nigra '14', P. simonii×P. nigra, and P. nigra×P. simonii 'Yingchun 5' were selected in Heilongjiang Province. The seedlings were planted with either individual species (cultivar) or 4 species (cultivars) mixed together for forestation. Total number of 2 880 three-year-old seedlings were planted with 5 treatments and 4 repeated areas covering an area of 6.7 hm². The height, DBH and crown width of poplar trees were measured from 2016 to 2019. From 2017 to 2019, 40 sample trees of each species (cultivar) in different planting modes were randomly selected, and the branches with a length of 40 cm in 4 directions were cut. The leaves damaged by defoliators were classified into 4 categories, and the damage rate was calculated according to 4 parameters: 1/4, 1/2, 3/4 and 1. Result: There were significant differences in tree height and DBH growth rate among treatments from 2016 to 2019. However the difference of growth rate among the species (cultivars) was greater than that affected by planting methods. DBH growth rate of Populus alba×P. berolinensis in mixed forest was significantly higher than that in pure forest (P < 0.05), and DBH growth rate of P. nigra×P. simonii 'Yingchun 5' in mixed forest was significantly lower than that in pure forest (P < 0.05). From 2017 to 2019, there was a significant difference in the growth rate of crown width among treatments. The crown width of each species (cultivar) in pure forest was larger than that of the corresponding species (cultivar) in mixed forest, but the difference was not significant. There was a significant difference in the leaf damage rate among treatments. The resistance to defoliators was in order of P. alba×P. berolinensis > P. simonii×P. nigra > P. simonii×P. nigra'14'> P. nigra×P. simonii 'Yingchun 5'. The leaf damage rate in mixed forest was between 4 pure forests. The leaf damage rate of P. alba×P. berolinensis in pure forest and mixed forest was relatively stable for three consecutive years; the difference was significant between P. simonii×P. nigra and P. simonii×P. nigra'14'in mixed forest in 2017 and 2018 (P < 0.05). Conclusion: In this study, it is illuminated that the difference in growth rate among poplar species (cultivar) is significantly greater than that influenced by planting modes. P. alba×P. berolinensis is the dominant species among the four species (cultivars), and P. nigra×P. simonii 'Yingchun 5' is the relatively weak one. The poplar species (cultivar) show additive effect in mixed forest. The growth competition among species (cultivar) exists the phenomenon that the strong is stronger and the weak is weaker. The defoliators resistance between P. simonii×P. nigra and P. simonii×P. nigra'14'is significantly different in mixed forest. The leaf damage rate in mixed forest is relatively stable for three consecutive years, which is similar to the dominant tree species, P. alba×P. berolinensis in pure forest. The leaf damage rate of the other three species (cultivars) changes greatly. P. nigra×P. simonii 'Yingchun 5' has the largest leaf damage rate in mixed forest. Except for P. alba×P. berolinensis, the leaf damage rate of each species (cultivar) in mixed forest is lower than that in pure forest, showing the non-additive effect of association resistance. According to the above conclusions, we suggest that poplar plantation should strengthen the diversified allocation of tree species or cultivars, and it is better to mix the dominant tree species (cultivars), which can improve the association resistance, reduce the incidence of diseases and defoliators, and improve the stand quality and production.

Object: In order to provide technical support for applying glue working procedure and determination of resin content, this paper proposed a method by near infrared spectroscopy (NIR). Method: Eucalyptus fibers were used as the research objects and resin content was used as the discriminative index. For the same batch of eucalyptus fiber, its moisture content was about 5%. Four kinds of resin contents, including 0%, 3%, 12% and 20%, were established for four categories of none, low, medium and high level, respectively. The partial least squares regression (PLS) model between the four categories and those NIR was established. Partial least-squares discrimination analysis (PLS-DA) was used to detect the effects of collecting spectra (dynamic and static) and fibers setting time. Result: 1) With the increase of resin content, the absorbance of NIR increased. Four categories of eucalyptus fibers could be distinguished. The spectrum data were established into high relevance and accuracy models, the accuracy of the models were 100%. 2) Collecting spectra (dynamic and static) did not affect the modeling, the accuracy of the models were 100%. If fibers were set a long time, the accuracy of the models were nearly 0%. Conclusion: According to the wood fiber of different resin contents, the absorbance of NIR was different, the resin content of wood fibers could be accurately determined by PLS-DA. Through the laboratory simulation experiment, dynamic or static fibers did not affect the accuracy of model establishment and discrimination. It was expected to provide some ideas for online determination of resin content of wood fiber.

Objective: This study was carried out to discuss the applicability of cantilever plate first-order bending mode method (dynamic method) and cantilever plate static bending method (static method) to test the longitudinal and horizontal Poisson's ratio of oriented strand board (OSB). Method: The dynamic and static stress and strain analysis of OSB cantilever plates were carried out using ANSYS modal program block and static bending program block, and the OSB longitudinal and horizontal cantilevers with an aspect ratio of 3 to 6 and a width to thickness ratio of 4 to 10 were calculated. The stress and strain of the plate, the position where the horizontal stress in the cantilever plate being equal to zero was determined, that is, the position of the strain gauges for dynamic and static tests of OSB longitudinal Poisson's ratio and horizontal Poisson's ratio, and the binary regression analysis was applied to express it as dependent on the relationships between the width to length ratio and the thickness to width ratio of the cantilever plate specimen. Result: For the OSB made in China and Canada, the longitudinal Poisson's ratios of the dynamic test were 0.342 and 0.314, and the horizontal Poisson's ratios were 0.131 and 0.174, respectively. The patch positions of the dynamic and static OSB Poisson's ratios were different, but it could test a fairly consistent OSB Poisson's ratio. Conclusion: The first-order bending mode method of the cantilever plate and the static bending method of the cantilever plate might be suitable for testing the longitudinal and horizontal Poisson's ratio of OSB, and their effectiveness could be verified by the axial tension method and the four-point bending method.

Objective: The bearing properties and failure modes of single bolted steel-bamboo scrimber (BS)-steel connections were studied, to provide some references for the design and application of bolted connection for bamboo structure. Method: Influence factors such as bolt diameter, main member thickness and end distance were designed by orthogonal scheme, to systematically analyze the influence laws of the initial stiffness (K₁), post-yield stiffness (K₂), yield load (F_y), ultimate load (F_u) and ductility rate of the connections which were tested under the uniaxial compression, by means of variance analysis and multiple comparisons, in order to reveal the bearing properties and failure modes of the single-bolted connections of steel-BS-steel. Result: The bolt diameter had significant effects on initial stiffness (K₁), post-yield stiffness (K₂), yield load (F_y), ultimate load (F_u) and ductility rate, of which the former four parameters were all increased with bolt diameter, while the latter ductility rate was decreased. Except for the yield load (F_y), the effects of the main member thickness on the initial stiffness (K₁), post-yield stiffness (K₂), ultimate load (F_u) and ductility rate were all prominent. Besides, the post-yield stiffness (K₂), ultimate load (F_u) and ductility rate were remarkably affected by the end distance, while its effects on the initial stiffness (K₁) and yield load (F_y) were reversely. Moreover, the effective failure modes of the single-bolted steel-BS-steel connections were presented as type-Ⅱ or type-Ⅲ. The yield mode of bolt was presented as "single-hinge" failure when the L/D value was from 3.75 to 6.00, while it was presented as "double-hinge" failure mode when the L/D values was from 6.00 to 13.50. Conclusion: The bearing capacity and failure mode of the single-bolted steel-BS-steel connection were affected by the bolt diameter, end distance and main member thickness simultaneously. It was suggested that the minimum dimensional requirement of the main member thickness and end distance could be set as 90 mm and 4d, respectively, for the bearing capacity tended to be stable and the ductility rate reached to the best state. Furthermore, the yield mode of bolt was gradually changed from "single-hinge" to "double-hinge" with the increase of L/D value, when the specimen satisfied to the minimum dimensional requirements of the end distance and main member thickness. Certainly, the failure mode of the connections that the dowel-bearing failure and bolt bending failure turned out simultaneously were relatively reasonable, which could give full play to the mechanical properties of all the members.

Objective: In order to satisfy the prevention and control needs of different biological hazards of ancient building wooden components, a kind of water-based organic preservatives were planned to be developed. Method: A series of preservatives were developed by the combination of propiconazole, 1, 2-benzoisothiazolin-3-ketone (BIT) and lambda-cyhalothrin with an excellent anticorrosion effect. The stability of the preservatives and the anti-erosion performances of treated wood were tested, and the anti-corrosion effects of the preparation were comprehensively evaluated by means of laboratory anti-corrosion test and field fast anti-pest test. Result: After diluted 250 times with water, the microemulsions were kept translucent for more than 60 days. These microemulsions were not freeze at-25℃ overnight. The fixation rate of the effective components of the medicament was over 90%. The fixation rate of chemicals in wood was related to their solubility in water. The component with high solubility had a low fixation rate. The appearance color of treated wood was almost unchanged. The result of indoor corrosion resistance test showed that the wood mass loss rate was less than 5% under the condition above 161.3 g·m^-3 (propiconazole/lambda-cyhalothrin=20:1). The test result of termite control in the field showed that under the condition of drug loading of 134.8 g·m^-3 (propiconazole/lambda-cyhalothrin=20:1), the anti-corrosion performance was 10, and the anti-termite performance could reach 10, and the anti-termite performance of untreated wood was 5.8. Conclusion: Water-based organic preservatives were developed, which could adjust the proportion of effective ingredients flexibly according to the different needs of the actual biological hazard control of ancient buildings. The microemulsion contained propiconazole, BIT and lambda-cyhalothrin, and had effective component content of more than 10%. The microemulsion not only showed stable performances but also had a high fixation rate of its active component in wood, so it had good anti-corrosion and anti-insect effect.

Objective: Forest carbon sequestration and emission reduction is an important part of national carbon trading. As the executors and stakeholder of the forest carbon sequestration project, identifying the endogenous and exogenous factors of farmers' continuous participation in the forest carbon sequestration project is of great significance for the stable promotion of the project and the mitigation of global climate change. Method: Based on the theory of endogenous and exogenous incentives, explore the internal and exogenous factors that influence farmers' continuous participation in forest carbon sequestration projects. This article constructs four dimensions of exogenous incentives of "policy concern", "project subsidy", "model effect" and "carbon sequestration-increasing training", and the three dimensions of "forest land value maximization", "carbon sequestration industry recognition" and "mitigation of climate change" of value recognition. Based on 417 sets of field survey data of farmers who have participated in the first phase of carbon sequestration project of bamboo forest in Suichang and Jingning counties of Zhejiang Province that implemented the Chinese Certified Emission Reduction (CCER). The relationship among exogenous incentives, value recognition and farmers' willingness of continuous participation is analyzed by statistical description. Binary probit model and mediating effect model were used to analyze the direction and extent of the impact of exogenous incentive and value recognition on farmers' willingness to participate in forest carbon sequestration projects and the mediating role of value recognition. Result: The results of cross analysis showed that: the proportion of exogenous incentives and value recognition factors to promote farmers' willingness to participate in the sustainable development was more than 98%. The Chi square test at a significant level of 5% indicated that different exogenous incentive factors and value recognition factors had a significant impact on farmers' continuous participation in forest carbon sequestration projects. The empirical analysis showed that: 1) In exogenous incentives, "policy concern" had positive impacts on farmers' continuous participation at a significance level of 10%, "project subsidies", "role models" and "the carbon sequestration-increasing training" had positive impacts at a significance level of 5%. 2) The "mitigation of climate change" in value recognition had a positive impact on farmers' continuous participation at a significance level of 5%; while "maximum value of forest land" and "recognition of carbon sequestration industry" had no significant impact on farmers' continuous participation. 3) Exogenous incentives had a significant positive impact on value recognition. And value recognition had a significant partial (25.99%) role of mediating between exogenous incentives and farmers' continuous participation in forest carbon sequestration projects. Conclusion: Farmers' continuous participation in forest carbon sequestration projects is the result of joint impact by exogenous incentives and endogenous value recognition. "Policy concern", "project subsidy", "model effect"and"carbon sequestration-increasing training" in the exogenous incentives and "mitigation of climate change"in the value recognition are important factors affecting farmers' continuous participation. Exogenous incentives have a significant positive effect on value recognition, and value recognition has a significant role in partially mediating between exogenous incentives and farmers' continuous participation in carbon sequestration projects.

Objective: To deeply understand the characteristics of spatial pattern of climbing bamboo in Hainan Island and reveal the ecological process of its population dynamics, and to provide basic data and theoretical support for the protection and management of tropical rainforest and the maintenance and restoration of biodiversity, the paper presents a study of spatial distribution and correlation between Dinochloa orenuda and Bonia levigata in Ganshiling, Hainan Island. Method: Based on a 1 hm² sample plot of National Long-Term Ecosystem Research and Monitoring Station for Bamboo and Rattan Forest in Sanya of Hainan Province, two native climbing bamboos, D. orenuda and B. levigata, were selected to analyze the intraspecific and interspecific spatial distribution and correlation of climbing bamboo populations in the tropical rainforest of Ganshiling by using the paired correlation function g(r) of point pattern analysis. Result: Spatial pattern and spatial scale of climbing bamboo populations are closely related. On small and medium scale, D. orenuda population was significantly aggregated on the scale of 0.5-34.5 m, B. levigata population was aggregated on the scale of 0.5-13.5 m. However, at a larger spatial scale, uniform distribution and random distribution appear alternately. The spatial correlation between D. orenuda and B. levigata populations varies greatly with different scales. On the whole, the spatial relation varies with the distance between them. On small and medium scale as 0-35.5 m, there is a significant negative correlation between them. With the slow increase of scale, the two types of climbing bamboo tend to be uncorrelated.When the distance scale between them is about to break through the upper limit of the edge of 100 m, there is a positive correlation between them. Conclusion: In the populations of D. orenuda and B. levigata, their spatial distribution were basically the same. The difference was that compared with B. levigata, D. orenuda's aggregation scale range is larger. As a plants from the same family, under the condition of resource constraints, on a small scale(0-35.5 m), they are mutually exclusive because of the competition. On a large scale, they can coexist better.

Objective: Embryogenic callus of Catalpa bungei was used to establish an effective genetic transformation system, in order to provide a basis for the genetic improvement of C. bungei in the future. Method: Agrobacterium-mediated genetic transformation was carried out with embryogenic callus as explants. The optimal genetic transformation conditions were obtained through orthogonal test, and then exogenous genes were transferred into C. bungei. Result: Selective pressure screening was performed in 1/2 MS medium with different gradient concentrations of kanamycin. The differentiation rate of embryogenic callus was 0.00%, and the survival rate was only 5.71% in 1/2 MS medium supplemented with 60 mg·L^-1 Kana. Therefore, 60 mg·L^-1 Kana was identified as the selective pressure for genetic transformation of C. bungei. The orthogonal design was carried out by L₁₈(3⁷) table in Agrobacterium-mediated genetic transformation experiments. The transient expression rate was obtained by GUS histochemical staining. The intuitive analysis of the orthogonal test and one-way ANOVA were performed to the data obtained from the experiment. The results showed that Agrobacterium-mediated transformation efficiency was the highest under the conditions of 2 days of pre-culture, EHA105 of Agrobacterium strain, OD₆₀₀ 0.7 of liquid concentration, 300 μmol·L^-1 of acetyleugenone(AS), 10 min of infection, and 5 days of co-culture time. And the two factors that have the biggest influence on the transformation efficiency are AS concentration and pre-culture time. A total of 32 resistant tissue groups were obtained by screening and culture of the infected embryogenic callus for 8 months. PCR detection was conducted on 15 resistant callus with high proliferation. The results showed that 86.67% resistant tissue groups had exogenous genes integrated into the genome of C. bungei. Endogenous hormone levels affect somatic embryo differentiation, cytokinin(CTK) and abscisic acid(ABA) promote somatic embryogenesis, and auxin(IAA) and gibberellin(GA) inhibit somatic embryogenesis. According to the determination of endogenous hormones, the levels of CTK and ABA in transgenic resistant tissue were significantly lower than those in the embryogenic callus of wild-type, while the levels of IAA and GA were significantly higher than those in the wild-type callus. Therefore, the level of endogenous hormones may be the reason for the poor somatic embryo differentiation ability of transgenic resistant tissue of C. bungei. Conclusion: Through Agrobacterium-mediated transformation of the embryogenic callus of C. bungei, PCR detection was conducted on 15 screened resistant callus, among which 13 resistant callus had integration of exogenous genes. The somatic embryo differentiation ability of transgenic resistant tissues is poor, and the change of endogenous hormone level may be the reason that the resistant callus is difficult to differentiate.