Objective: In order to quantitatively reveal the patterns of transpiration and water consumption of different forests in different succession stages,we investigated the water use of representative forest types in subalpine areas of Western Sichuan,China,intending to provide a scientific basis for tree species selection for forest restoration,water holding capacity improvement and poor-efficiency forest revitalization in the subalpine areas of Western Sichuan,China. Method: In the subalpine region of western Sichuan,China,three typical forest types of old primary forest (Abies faxoniana)(PF),secondary forest (Betula albo-sinensis)(SF),and plantation forest (Picea asperata)(PL) in terms of age,forest type and area were selected from forest restoration projects for the study. We used thermal dissipation sap flow sensors to measure stem sap flow of sample trees. With sapwood area as the scaler,water use from individual trees were scaled up to estimate forest canopy transpiration for the three forest types. Next,with the relationship between daily forest transpiration and meteorological factors formulated by the random forest regression algorithm (RF),we interpolated the missing daily canopy transpiration for each forest type. Result: The maximum daily canopy transpiration observed during the growing season (May-Oct.) for PL,SF,and PF were 3.17,2.08,and 1.69 mm·day^-1,respectively. RF performed well in predicting daily canopy transpiration for the three forest types. Total accumulated canopy transpiration for each forest type during the growing season was calculated based on the daily water use estimated by the RF regression algorithm. As a result,PL has the maximum canopy transpiration (314.10 mm),followed by SF (199.28 mm),and PF had the lowest canopy transpiration (125.47 mm). In comparison with previous observation of water use for the broad-leaved Quercus aquifolioides dwarf forest in this region,the canopy transpiration of the three forest types is much smaller than that of the Q. aquifolioides forest. The total canopy transpiration estimated for Q. aquifolioides is 88.77 mm in July. Conclusion: Overall,the canopy transpiration of SF in early stage of succession is higher than that of PF in late stage of succession. The canopy transpiration of plantation forest (PL) is much higher than that of natural forests (primary coniferous forest PF and natural secondary forest SF). This implies the vegetation restoration approach via large-scale spruce plantation may impose pressure on the water resources of catchment basins in the short term. The characteristics of forest transpiration and water consumption can be used as the evaluation indicators of forest restoration in this area. Finally,in combination with previous studies on forest evapotranspiration in the study area,we came up with the ecological succession hypothesis of forest water use:with the forward development of forest succession,forest water use will tend to decrease,and the zonal climax community-subalpine dark coniferous forest-has the lowest water consumption. This hypothesis can be used as a reference system for maintaining regional hydrological balance and adjusting vegetation structure in the study area.

Objective: Characterization of the spatial distribution of throughfall and stemflow in Pinus massoniana forests and their regulating factors were investigated in order to provide a scientific basis for accurately quantifying the distribution of precipitation in P. massoniana forests and evaluating their water conservation function. Method: In May 2017, in a P. massoniana forest,we installed 16 throughfall collectors with a cross-sectional area of 3 000 cm² and selected 27 standard trees of P. massoniana to study the spatial variation of their stemflow. We used Pearson correlation to analyze relationships between canopy structure parameters and spatial variability of throughfall and stemflow and employed Monte Carlo simulations to determine the amount of rainfall collector needed to accurately estimate throughfall within a certain error range. Result: During the study period the gross rainfall in open field was 1 008.4 mm,and the amounts of throughfall and stemflow were 829.8 and 14.4 mm,respectively,accounting for 82.3% and 1.4% of the gross rainfall. Both ratios of stemflow volume and stemflow volume increased with the increase of the gross rainfall,but coefficient of variation of stemflow volume decreased with the increase of the gross rainfall and tended to be stable after 60%. The stemflow volume was positively correlated with crown area and DBH (P < 0.01). The throughfall ratio increased with the increase of rainfall,and tended to be stable after throughfall reached 87%,showing a "S" curve (P < 0.01). Throughfall showed a large spatial heterogeneity,and the coefficient of variation significantly decreased first and then stabilized with the increase of rainfall. The relationship between coefficient of variation of throughfall and rainfall was fitted by a reciprocal function (P < 0.01). Characteristics of the canopy structure were the main factors influencing the spatial variability of throughfall,but their effects varied with rainfall. The leaf area index,the canopy thickness,the distance of the measuring point to the trunk and the canopy coverage all affected the spatial distribution of throughfall,and among them,the leaf area index had the greatest influence. Different rainfall levels reached the same error level in the same confidence interval,and the number of throughfall collectors used was different. With the increase of rainfall level,the same level of error could be achieved with less throughfall collectors. When the rainfall level was 0-10 mm,the number of throughfall collectors used was the largest,i.e.,under the 95% confidence interval and within the 5% error range,the minimum number of throughfall collectors required was 13. When the rainfall level was greater than 40 mm,the number of throughfall collectors used to achieve the same error level was the least,i.e.,under the 95% confidence interval and when the measured throughfall was maintained within the 5% error range,the minimum number of throughfall collectors required was six. Conclusion: The spatial variability of throughfall and stemflow of P. massoniana were influenced by rainfall and canopy structure. The spatial heterogeneity of throughfall and stemflow decreased with the increase of rainfall,and then tended to be stable. However,the stability coefficient of the stemflow was greater than that of throughfall. The canopy structure determined the overall pattern of the spatial distribution of throughfall,and among them the leaf area index and throughfall ratio had the strongest impacts. DBH had the most significant effect on stemflow. At the reference rainfall level of 0-10 mm and under the confidence interval of 95% or 90%,at least 13 or 11 collectors should be installed with a cross-sectional area of 3 000 cm² in a 50 m×50 m plot if the value of throughfall was controlled within the range of the 5% error.

Objective: To reveal the key stand spatial structure factors affecting soil nutrients and to provide a scientific basis for the establishment of optimal forest spatial structure in order to improve soil nutrients in forest. Method: The relationships between stand spatial structure factors and soil nutrient contents were developed,analyzed and compared by using Pearson correlation coefficient,multivariate linear regression and canonical correlation analysis in four typical artificial forests (a pure coniferous forest,a pure broad-leaved forest,a mixed broad-leaved forest,a mixed broad-leaved and coniferous forest),a natural secondary forest and a bamboo forest in central subtropical China. Result: The spatial structure of the natural secondary forest was optimal and the contents of soil organic matter (SOM),nitrogen (N) and phosphorus (P) were the highest among the examined forest types. No regularity was found for the relations between spatial structure and SOC,N,P,and potassium (K) contents in the other five forest types.The stand mingling degree,uniform angle and forest layer index were significantly positively correlated with SOM,total N,and available P,respectively (P < 0.05). The stand mingling degree and forest layer index were the dominant factors affecting SOM and available P,and the primary factor affecting soil total N was the stand mingling degree. The correlation coefficient of the first group of canonical variables was 0.951 (P < 0.01),indicating that the spatial structure of stand was highly correlated with soil nutrients. Particularly,the stand mingling degree and forest layer index played a critical role in the overall influence on soil nutrients. Conclusion: Our study indicated that the stand spatial structure significantly affected soil nutrient content in the study site. The stand mingling degree and forest layer index were the key stand factors determining SOM,available P and soil nutrient level,while the stand mingling degree was the main factor controlling total soil N content in the examined forests.The result: suggested the soil fertility could be improved by adjusting tree species composition of the stands and forest layer in the study region..

Objective: The azimuthal difference of sap flux density is one of the important factors affecting the accuracy of individual transpiration estimation. Because of asymmetry of sap flow in different azimuths,how to simplify the treatment to better estimate the average sap flow rate of a plant will be very important Method: In this study,the thermal dissipation technique (TDP) was used to continuously and synchronously monitor the sap flux density of the four vertical orientations of the trunk of Pinus sylvestris var. mongolica during the whole growing season in Horqin sandy land,and the precipitation and soil moisture content were also synchronously measured. Result: The relative sap flux density (the sap flux density divided by the maximum value during this azimuth observation,J_s/max) of P. sylvestris var. mongolica had significant azimuthal variation (P < 0.01),among which relative sap flux density in south-side (J_s/max-S) is the highest. The values of J_s/max from four azimuthal directions in a tree showed significant inter-individual differences,and there was no distinct relationship between them. Soil water deficit was able to cause a synchronous and significant decrease in sap flux density of all directions (P < 0.05). By comparing the representativeness of the mean sap flux density (the mean value of four vertical directions) of the whole tree in different directions,a simplified model for estimating the mean sap flux density of the whole tree was established with the sap flux density on the north side of the trunk (J_s/max-N) (slope=1.015,Adj.R²=0.99,P < 0.01). The model has an accuracy of 0.99 by independent sample testing. Conclusion: There are significant differences in the sap flux density in different azimuths of P. sylvestris var. mongolica trunk,and the differences also varied in individuals. There is a high correlation among J_s/max in different directions. For P. sylvestris var. mongolica grown in sandy land,the average sap flux density of the whole tree can be accurately estimated with the sap flux density measured from the north-side of the trunk.

Objective: The autumn leaf color of red maple(Acer rubrum) changed from green to red or yellow, which was closely related to the content of anthocyanin in leaves. With the increasing demand for directional breeding of garden plants, this paper aims to reveal the mechanism of anthocyanin biosynthesis in red maple and provide theoretical basis for directional improvement of its leaf color. Method: In order to analyze the changes of anthocyanin metabolite accumulation and gene expression level, this study employed green leaves, red leaves and yellow leaves of red maple color mutant as experimental materials, and applied UHPLC-QE-MS and high-throughput RNA sequencing method for metabolome and transcriptome analysis, respectively. Result: 1) In the comparison group of red-green leaves, yellow-green leaves, red-yellow leaves, 1 377, 1 793 and 1 098 differential accumulated metabolites were detected respectively under the positive ion mode, 789, 699, 677 differential accumulated metabolites were detected respectively under the negative ion mode: in red leaves, the content of cyanidin, pelargonidin and delphinidin and their derivatives increased significantly compared with green leaves; in yellow leaves, the content of cyanidin, delphinidin and its derivatives increased, while the pelargonidin and its derivatives decreased compared with green leaves. 2) In the above-mentioned three comparison groups, transcriptome sequencing detected 28 536, 43 017, 27 110 differentially expressed genes, respectively: compared with green leaves, 89.5% gene expression in the anthocyanidin synthesis pathway of red leaves increased, 66.7% gene expression in the anthocyanidin synthesis pathway of yellow leaves increased. 3) In the anthocyanidin biosynthesis of red maple, there were 29 differentially accumulated metabolites and 48 differentially expressed genes. 4) Network interaction analysis of differential metabolites and genes showed that CHS2, CHS7, CHS8, F3H1, F3H5, F3H7, F3H8, F3H10, F3′H2, LAR, FLS1, FLS2, UFGT4 negatively regulate the synthesis of pelargonidin derivatives and delphinidin derivatives, and UFGT5 positively regulate the synthesis of cyanidin derivatives. Conclusion: When red maple leaves change color in autumn, the expression of a large number of genes in the anthocyanin pathway is up-regulated, and the content of cyanidin 3-(6″-acetyl-galactoside) and cyanidin 3-arabinoside increased, which is one of the main reasons why leaves change the color.

Objective: Tamarix austromongolica is an endemic species distributed along the Yellow River Basin in China. The purpose of this study was to explore the genetic structure and diversity of the T. austromongolica populations. Method: Using the chloroplast DNA fragment (trnQ-rps16) and the nuclear gene fragment,the Internal Transcribed Spacer (ITS) to study the genetic diversity,the genetic structure and the historical dynamics of 266 individuals in seventeen populations of T. austromongolica distributed in the Yellow River basin of China by PCR amplification and sequencing. Result: Four chloroplast haplotypes in 207 individuals and 32 nuclear haplotypes in 232 individuals were detected. The genetic diversity of T. austromongolica based on chloroplast gene analysis was low (H_T=0.13),however,the genetic diversity of nuclear genes was high (H_T=0.82). The AMOVA analysis of chloroplast gene(cpDNA) and nuclear gene(nDNA) fragments showed that the genetic variation of T. austromongolica populations mainly occurred within populations. The genetic differentiation coefficients N_ST (cpDNA:0.15; nDNA:0.22) and G_ST (cpDNA:0.19; nDNA:0.24) were not significant (P>0.05),indicating no significant phylogeographic structure between populations. The Tajima's D and Fu's Fs of neutrality tests both showed negative results and the mismatch analysis showed that the distribution curve of the expected population expansion is consistent with the actual observed distribution curve,indicating that the T. austromongolica has undergone a rapid population expansion. According to the results revealed by the chloroplast genes,the haplotypes,polymorphisms and nucleotide diversity of T. austromongolica distributed in Yongjing county and Jishishan county,Gansu province,were significantly higher than those in other regions,and had unique haplotypes (H2,H4),indicating that T. austromongolica near these areas was the oldest. The population of T. austromongolica migrated to the upstream (Qinghai province) and the middle and lower reaches respectively from Gansu province. The founder effect caused the genetic diversity of newly-built populations to be lower. Conclusion: This study revealed the genetic structure and diversity of T. austromongolica. The genetic variation of populations of T. austromongolica mainly occurred in the population,and there is no significant phylogeographic structure between populations. The species has experienced a rapid expansion. It is speculated that its origin center was near Jishishan county and Yongjing county in Gansu province. And the population of T. austromongolica migrated from Gansu province to the upstream and the middle and lower reaches respectively with the formation of the Yellow River. Our results suggest that the formation of Yellow River is an important factor leading to the migration and expansion of the populations of T. austromongolica.

Objective: The growth and variation characteristics of heartwood and sapwood,ring number of heartwood,and height of heartwood in different-aged teak (Tectona grandis) plantations in Daqing mountain of Guangxi were investigated,so as to provide scientific basis and basic data for understanding the developmental characteristics of heartwood,predicting heartwood quantity and efficiently cultivating high-quality and large-diameter teak target trees in this region. Method: Average trees from 10,18,31 and 41-year-old teak plantations in Daqing mountain of Guangxi province were selected to analyze variation of heartwood and sapwood among orientations and among individual trees using variance analysis,and the regression model between amount of heartwood and sapwood,cross-sectional diameter,and total number of annual rings were fitted by curve estimation method to study the growth variation of teak heartwood and sapwood. Result: The heartwood radius of teak trees was the largest in the north direction,while the sapwood width was the largest in the north and the east directions,and there were no significant differences in the heartwood radius and sapwood width among four stem orientations at the same age (P>0.05). The heartwood radius,heartwood area and sapwood area decreased with tree height regardless of ages. The sapwood width was relatively larger at the base of the trunk (0-1 m) and remained constant in a certain area. With the increase of forest age,the amounts of sapwood and heartwood increased in the four forests,and there was no significant difference in sapwood width (P>0.05),however there were significant differences in heartwood radius,heartwood area and sapwood area among forest ages (P < 0.01). The cross-sectional heartwood and sapwood increased with the increase of the cross-sectional diameter and the total number of annual rings,among which the influence of stem cross-sectional diameter was higher than that of the total number of rings,and the total number of annual rings had a great influence on the early development of heartwood. There was relatively large tree-to-tree difference in the amounts of sapwood and heartwood,as well as the maximum heartwood height of teak trees for the same forest age,in which the degree of variation in the areas of heartwood and sapwood was similar,and the degree of variation in the heartwood radius,the sapwood width,and the disappeared maximum height of the heartwood were also similar to each other. Teak began to form heartwood at the age of four years. The number of heartwood rings of different ages increased with the increase of the total number of annual rings. The total number of annual rings accounted for more than 80% of the variation in the number of heartwood rings. The annual growth rates of 10-,18-,31-and 41-year-old teak trees were 0.9 ring,0.7 ring,1.0 ring,and 1.0 ring,respectively. The maximum height and relative height of heartwood were positively correlated with forest age,with the increase of forest age,the heartwood disappeared at a higher position of the trunk. Conclusion: The initial age of heartwood formation of teak trees was 4 years,which was a tree species with early heartwood formation. Within each forest age,the orientation had little effect on the heartwood and sapwood of teak trees. The heartwood radius,heartwood area,sapwood area and maximum heartwood height increased significantly with the age of teak trees,while the heartwood width did not change significantly. The cross-sectional diameter could better explain the variation in the amounts of sapwood and heartwood,and the total number of rings only explain the variation in the amount of heartwood prior to 31-year-old teak trees. According to the study,41-year-old teak heartwood still has great growth potential,and longer cultivation is needed to reach the goal of high-quality and larger-diameter teak trees.

Objective: Ginkgo biloba is one of the most important tree species in China. Real-time, quantitative and accurate estimation of its eLAI(effective leaf area index) plays a key role in analyzing its growth and competition as well as understanding the functions and productivity of the plantation ecosystems. Method: Combined with the point cloud data acquired from the multi-rotor UAV-based LiDAR system and 45 sample plots data, this paper used the following two approaches:gap-fraction modeling(calculating the canopy gap fraction of the point cloud, then computing eLAI according to the Beer-Lambert law)and statistical modeling(modeling based on the eLAI measured from ground and the metrics derived from LiDAR first return, then the fitted models were applied to calculate the eLAI)method, to estimate the eLAI in a typical ginkgo plantation of China. Result: 1) When using the statistical model to estimate the eLAI, the accuracy of estimation was R²=0.38(rRMSE=54%) by modeling of LiDAR height metrics only. By gradually introducing multiple sets of metrics (density metrics, canopy volume metrics and intensity metrics), the accuracy of the estimation was increased to R²=0.64(rRMSE=26%), R²=0.61(rRMSE=28%)and R²=0.74(rRMSE=23%), respectively. 2) The sample plots were grouped according to Cover, the accuracy of group modeling was better than that of non-group modeling. 3) When using the gap-fraction model to estimate the eLAI, the accuracy was R²=0.71(rRMSE=32.0%). Conclusion: Combining multiple sets of LiDAR metrics to estimate the eLAI could fully excavate the canopy structure characteristics contained in LiDAR data, so as to improve the estimation accuracy. Meanwhile, the gap-fraction model approach could effectively estimate the eLAI of ginkgo plantations. This study illustrated that the metrics obtained from the UAV LiDAR might have certain potentials in estimating the eLAI of the ginkgo plantations.

Objective: There are many models of management in artificial forests, and they have strong dependence on statistical methods. The coupling between the traditional assistant decision-making support systems for artificial forest management and model libraries and method libraries is relatively high, and the commonality of model libraries is not high. The problems of high coupling of business code and method code also exist. Based on the above-mentioned statuses, combined with the diversity of forestry mathematical models, this paper establishes a model library and method library platform of artificial forest to realize the scientific management and information service of the model and method of artificial forest. Method: Based on the invocation mechanisms of different model representations and methods, the relational database construction theory was used to design the relational model between the model library and the method library. For equation expression models, lexical analysis, grammar analysis, semantic analysis, etc., were introduced in order to realize the analytical calculation of the equation model; for the procedural model, the model parsing calculation was implemented by calling the package; the call and management of the method library were realized based on the package call method of the package. Using the idea of data coupling, the model library, method library, and decision-making application system were decoupled to achieve independent management and standardized shared services of models and methods. Result: The model base system could realize the storage, management and analysis of mathematical formula model and program block model; the method base system could realize the storage and management of method program block, the user-oriented model and method oriented computing service, and application-oriented API calling service is, respectively, realized by building the interaction format of model and method data. Conclusion: A general model and method data interaction structure is designed, and a service platform of model base and method base for plantation management is also constructed. The management and analysis of model and method based on web is realized, and the sharing and calling function of model and method is also provided.

Objective: Monochamus alternates, causing great economic losses every year, is not only an important borer pest in pinewood, but also the main vector of pine nematode disease. To screen for more effective biocontrol agents against M. alternates, four Metarhizium strains were identified by molecular and morphological characteristics, and their virulence against M. alternates adults was analyzed. Method: In this study, cultural characteristics and conidia morphology of four Metarhizium strains were observed respectively. The EF-1α gene of each strain was cloned and sequenced, and a phylogenetic tree was constructed to comprehensively identify the taxonomic status of 4 strains to species level. The virulence of four Metarhizium strains against M. alternatus adult was tested with different conidia concentrations and inoculation methods(dipping, twig dipping, and nonwoven cloth), and the pathogenesis was evaluated. Result: 1) WP08 and WTKH were clusted into the clade of M. pingshaense, and LV2 was into M. anisopliae, and qc1401 was into M. pemphogum. 2) Among the four strains, WP08 and LV2 caused the highest corrected death rate (100%) in the 40-day experimental period, and the corrected death rate of qc1401 and WTKH was 91.9% and 87.9%, respectively. Lethal speed of each strain was in the order of WP08 > LV2 > qc1401 > WTKH with the LT₅₀ of 5.52, 10.38, 16.93 and 20.80 d, respectively. 3) Among the conidium concentration series of 1.0×10⁸, 1.0×10⁷, 1.0×10⁶ conidia·mL^-1 of WP08, the higher the conidia concentration, the higher the corrected death rate and the shorter the lethal time of M. alternatus adults. The corrected death rate was as high as 100% at conidium concentration of 1.0×10⁸ and 1.0×10⁷ conidia·mL^-1 of WP08, and was 83.9% at conidium concentration of 1.0×10⁶ conidia·mL^-1, and the LT₅₀ was 11.38, 16.44 and 24.22 d at the three concentration, separately. 4) For strain of WP08, all the three inoculation method could cause a death rate of 100% in the experimental period of 40 days, and the LT₅₀ of insect dipping, twig dipping, and nonwoven cloth were 5.52, 11.38, and 17.21 d, respectively. Conclusion: Four Metarhizium strains are identified as M. pingshaense, M. anisopliae, and M. pemphogum, and all the strains can infect M. alternatus adults and cause their death. M. pingshaense WP08 strain exhibits higher death rate and faster lethal speed than the other three stains, and shows great potential as biocontrol agent for M. alternatus.

Objective: This paper aims to quantitatively evaluated the effects of site factors on the occurrence degree of Japanese red pine (JRP) needle blight disease in pure pine forests, by constructing the disease based index (DBI) evaluation system of the pine disease. Method: Based on the main principles of forest disease occurrence, the result affecting the occurrence of JRP needle blight were attributed to the comprehensive effect of stand factors and site factors. Temporary sample plots were set up in the pure forest ecosystem of Japanese red pine with relatively consistent forest age (34±2 a) to screen the key stand factors affecting the occurrence of pine needle blight, establish the functional relationship between the key stand factors and the disease severity index of pine needle blight was established, and the optimal model was selected as the guide curve. The DBI curve group of pine needle blight was obtained by stretching the guide curve in an equal proportion, which in turn showed different disease based indexes from the bottom to the top, that is, the action level of the site on the occurrence degree of pine needle blight. Result: 1) Based on the mainprinciple of forest disease occurrence, the concept of disease based index (DBI) was proposed. 2) The quantitative method of disease based index of JRP needle blight was determined, which contained contains 9 steps:set the plots, investigate the disease severity index of stands, investigate the stand factors, screen the key stand factors, determine the datum of stand factors, establish alternative guide curve model, determinate and evaluate guide curve model, draw the guide curve as well as establish the curve groups. 3) Stepwise regression analysis showed that stand density was the key stand factor affecting the occurrence of JRP needle blight. The guide curve equation was established according to the proposed quantitative method:Q=65.61/(1+e^{-0.0015x+2.32}), and the determination coefficient R²=0.519 8, indicating that the fitting equation was reliable. When this model was used to estimate the disease severity index of JRP needle blight, the average estimation error is 5.35%.4) A quantitative evaluation system was established by stretching the main curves of the disease base index of red spot blight in equal proportions to form a curve group. The 5 curves of the system from bottom to top were:Ⅰ-light disease occurs, Ⅱ-mild disease occurs, Ⅲ-moderate disease occurs, Ⅳ-severe disease occurs, Ⅴ-especially severe disease occurs. Conclusion: The guide curve model and curve group diagram of the disease based index of Japanese red pine needle blight can quantitatively evaluate the effect of site factors on the potential occurrence degree of pine needle blight, which can provide a theoretical basis for rational and effective management of pure Japanese red pine forest, and will become an important part of the ecological control method of forest pests.

Objective: Quercus virginiana (Fagaceae), native to the southeastern United States, is recently introduced to the Yangtze Delta and often planted as landscape and coastal shelter forests. Quercus root tips are often heavily colonized by a phylogenetic diverse group of ectomycorrhizal (ECM) fungi, which improve nutrient acquisition and stress resistance for host plants. The purpose of this work is thus to reveal the identities of ECM fungi associated with Q. virginiana roots in the new environment. Method: The ectomycorrhizal root samples were collected at four different stages from October 2017 to August 2018 and traditional morphological description, fungal amplicon-based high-throughput sequencing approaches were used to investigate the diversity and structure dynamics of ectomycorrhizal fungi associated with Q. virginiana. Result: All the examined ectomycorrhizas showed black, white, yellow, and their intermediate colors (carmine and oyster white) appearances. The presence of mantle structure was observed microscopically. Based on the operational taxonomic units (OTUs) assignment and their relative abundances, the first three colored mycorrhizas corresponded to the fungi belonging to Tomentella, Scleroderma, and Russula, respectively, which showed rich interspecific genetic diversity inferred from phylogenetic analysis. Weighted Pair-Groups Method Average (WPGMA) cluster analysis of the OTU data matrix revealed that fungal compositions of the remaining two colored-mycorrhizas were very similar to those presented in yellow and black-colored mycorrhizas, respectively, indicating the different development stage of the same type of ectomycorrhizas. In addition, a few other ectomycorrhizal taxa including Amanita, Hebeloma, Pisolithus, Lactarius, and Sebacinales were detected with low abundances. The ectomycorrhizal community structure varied obviously in different sampling time. It is mainly shown as follows:Scleroderma dominated in all samples, its abundance was high at the initial stage, and then gradually decreased and subsequently maintained a stable abundance level; On the contrary, Russula had very low proportion in first sampling time, but increased its abundance gradually; Tomentella was not changed remarkably, with one exception was the second sampling time, in which Tomentella was abundant and comparable to Scleroderma. This observation was also consistent with the emergence of epigeous fruiting bodies of Scleroderma and Russula observed in the field. The non-metric multidimensional scaling analysis revealed that there were obvious differences in the ectomycorrhizal fungal communities of the root tips samples from four sampling periods of time (stress=0.157). Highest α-diversity indices (Chao1, ACE, Shannon, and Simpson) were observed in the ectomycorrhizal fungal communities of pooled samples collected at the second sampling period. Also, the greatest pairwise dissimilarity value occurred between the samples from the first and fourth sampling period of time based on β-diversity heatmap. Conclusion: The ectomycorrhizal fungi associated with Q. virginiana are mainly composed of Tomentella, Scleroderma and Russula. There are significant changes of ectomycorrhizal fungal communities at different growth stages, which are probably correlated with the changes of soil moisture and temperature. The results also gain the highlights on exploiting ectomycorrhizal fungi for mycobiont-based Q. virginiana cultivation technology.

Objective: In this study, based on the bird images, we construct a bird population identification model with the deep convolutional neural network theory by combining the global and local features fusion method, in order to provide a new approach for monitoring and management of forests and wetlands. Method: First of all, according to the physiological process of the object identification of human from entireness to part, the jump structure was used to implement the interaction between global and local information. In the proposed model, two model frameworks are mainly used to extract the global and local features of birds, and the jump structure is used to propose the fusion module structure for feature fusion, which transfers the global feature information to local feature extraction module. In the training stage of the model, we need to provide the labeling information on the local parts of birds, while in the test stage, we use Faster R-CNN model to automatically extract the labeling information on the local parts of birds. Secondly, we discussed the effects of different bird local image information on the model. Finally, the validity and applicability of the model are verified by comparing different network classification models and bird datasets. Result: The bird species classification model proposed in this paper has high classification accuracy, and the overall classification accuracy is over 90%. For the image information of different parts of a bird, the classification accuracy of the model shows a certain difference, among which the overall classification accuracy of the network classification model based on the bird's head image is the highest. The Faster R-CNN model has a high accuracy in bird part image locating. There is little difference in the overall accuracy between the manually labeled local image tag and the local image tag predicted by Faster R-CNN model in the test stage. Compared with the overall classification accuracy of the network classification models such as Inception-V1、ResNet-101、DenseNet-121 and Bilinear CNN, the overall classification accuracy of the model proposed in this paper is relatively high, that verifies the effectiveness of the proposed classification model of bird. Compared with the classification accuracy by using NABirds bird dataset, the overall classification performance of the proposed model is better, which verifies the applicability of the proposed model. Conclusion: The proposed bird species classification model has good identification results and effectiveness, which can provide a reasonable and effective basis for monitoring and management of forests and wetlands.

Objective: This study aimed to understand bird composition and quantity change trend in summer, and the effect of habitat changes on bird community composition in order to provide scientific basis for the protection and management of the Qagan Nur wetland of Inner Mongolia in China. Method: By using line- and point-sampling methods, bird surveys at the Qagan Nur wetland were conducted for six consecutive years in August of each year from 2009 to 2014. The dominance index, the diversity index and the evenness index of the bird communities were analysed with the collected data. The IBM SPSS Statistics, Excel software and R software were used to test the bird community differences for different years with the Chi-square test, and analyse the correlation between meteorological factors and bird composition in each year with the linear regression analysis. Result: A total of 171 species in 37 families within 18 orders were recorded. Among them, there were 99 species of summer birds, 53 species of migrants, 16 species of residents, 2 species of vagrants and 1 species of winter bird. According to the habitat chosen by these birds, there were 58 species of grallatores, 50 species of songbirds, 41 species of natatores, 13 species of raptors, 4 species of terrestores, and 5 species of scansores. According to their endangered status, there were 2 species ranked as key protected first class species in China, and 23 species ranked as key protected second class species in China. Baer's Pochard (Aythya baeri) and Siberian Crane (Grus leucogeranus) were listed as critically endangered; the Oriental White Stork (Ciconia boyciana), Saker Falcon (Falco cherrug) and Far Eastern Curlew (Numenius madagascariensis) were listed as endangered; There were 7 species listed as vulnerable and 10 species listed as near threatened by IUCN. There were 73, 44, 156, 126, and 92 species listed on the List of Bird Species in accordance with the migratory bird protection agreement between China and America, Australia, Russia, South Korea and Japan, respectively. In the six years, the similarity index for summer birds was relatively high, and the compositions of the dominant species, the typical species and the rare species changed in different years. The result of the Chi-square test showed that there were significant differences in the number of species, the number of birds and the diversity index across years. The number of orders and families increased significantly from year to year. The number of summer species, the percentage of resident species and the percentage of the relative number of resident birds also increased from year to year. The number of grallatores and natatores decreased, whereas the percentage of the relative number of songbirds increased significantly. The results of the correlation analysis between meteorological factors and bird composition revealed that bird families were significantly positively correlated with the min temperature. The diversity index and the evenness index were extremely significantly positively correlated with the min temperature. The dominance index was extremely significantly negatively correlated with the min temperature. The number of summer species was significantly negatively correlated with the max temperature and was extremely significantly positively correlated with the relative humidity. The percentage of the relative number of natatores was significantly positively correlated with the relative humidity. The number of natatores species was significantly negatively correlated with the average temperature. Conclusion: With the shrinking of the Qagan Nur wetland and lake, the increasing of saline alkali land, grassland and forest land, the species and quantity of grallatores and natatores have a downward trend, while the number of songbirds has increased. It is suggested that long-term avian surveillance systems should be established and that effective management methods should be taken to protect the bird communities and their habitats in the Qagan Nur wetland.

Objective: By testing the withdrawal strength of round nails and self-tapping screws those were driven into larch and spruce dimension lumber under different angles, the effects of driving angle between axial and wood fiber, wood density, and tangential face and radial face on the withdrawal strength were studied. Method: Round nails(Ø2.5 mm)and self-tapping screws(Ø4.0 mm), were respectively driven into the larch(Larix gmelinii)and spruce(Picea glauca)lumber, and the withdrawal strength was tested following the Chinese national standard, meeting the minimum requirement of edge and end distance and spacing of nails or self-tapping screws, nails or self-tapping screws were driven into dimension lumber at 90°, 60°, 45° and 0°, respectively, and then pulled out at constant speed of 3 mm·min^-1 using self-designed nail/screw withdrawal strength test holding device until the failure load. The influences of different parameters on nail/self-tapping screws withdrawal strength were estimated through calculation and comparative analysis of failure load. Result: 1) With the decrease of the driving angle, the load-displacement curve became more sharp, and the withdrawal strength value of self-tapping screw was obviously greater than that of round nails. The withdrawal strength of value nail/screw in larch with higher-density was greater than that in spruce, and the withdrawal stiffness of self-tapping screw in larch was obviously larger than that in spruce. But the shapes of curves in different angles were nearly the same. 2) The withdrawal strength of nail/screw which were driven at 90° was greater than that at 0°, but from 90° to 0°, the withdrawal strength increased firstly and then decreased, and the variation trend of withdrawal strength of self-tapping screw showed opposite. 3) The withdrawal strength of self-tapping screw driven in the radial face of spruce was greater than that in tangential face, but that of round nail was not regular. The withdrawal strength of round nail in tangential face of larch was smaller than that in radial face, but that of self-tapping screw was not regular. Conclusion: The angle had a significant influence on withdrawal strength of nails and screws. With the decrease of angle, screws withdrawal strength decreased firstly and then increased, the trend of round nails was opposite. There was no definite correlations between withdrawal strength in tangential face and radial face, and the parameter of driving angle with tree ring should not be considered in the calculation of withdrawal strength design value in timber structure. The formula recommend in European code for design of timber structures(BS EN 1995-1-1:2004)showed the withdrawal strength of screw fall off with the decrease of driving angle, but the test result indicated that the estimation of withdrawal strength at 0° was too conservative. When pulling out the screws driven in the end face, the damage was obvious brittle fracture. So an effective reinforcement and calculation of strength was necessary for the self-tapping screws connection in timber end face in practical timber structural engineering.

Objective: Formaldehyde released from wood-based panels and its products is identified as a highly carcinogenic substance by the international health organization, and the emission climate chamber methods is determined as one of detection methods in China. However, there is the phenomenon of the fog and the condensation using the existing climate chamber devices during the test processes, so that the detection results of formaldehyde released from wood-based panels and its products are not enough accurate. Therefore, an algorithm of gradual objective tracking is proposed in this paper, which could make the temperature and relative humidity of chamber without the phenomenon of the fog and the condensation to achieve high precision in the whole processes. Method: The control objective is divided into different segments in this method, f_{C_set}(t)={f_{C_set}(t₀), f_{C_set}(t₁), …, f_{C_set}(t_m-1), f_{C_set}(∞)±ξ, f_{C_set}(∞)}. The control algorithm which starts from the initial value selects the control sub-objective and the control parameters in each segment. The control sub-object f_{C_set}(t_i)(0 ≤ i ≤ m) becomes the next-stage control sub-object f_{C_set}(t_i+1) when a state reaches a neighborhood of the set sub-objective f_{C_set}(t_i). The PID algorithm is used for controlling in each segment, and the parameters of gain K_p, integral K_i and differential K_d are selected under the conditions of the non-condensing constraints, so that the climate chamber temperature and the relative humidity can quickly reach the defined conditions. Meanwhile, there is no phenomenon of the fog or the condensation inside the climate chamber all the time. The method of control proposed in this paper is applied to the designed climate chamber, and the wood-based panel furniture is identified and measured. Experiments have been carried out under the different environmental conditions in four seasons of the year, using the developed controller. Result: 1) The algorithm of the gradual objective tracking proposed in this paper can maintain the ability of anti-condensation during the whole test processes, so that there is no phenomenon of the fog and the condensation inside the climate chamber. 2) When the climate chamber is in a steady state, the maximum deviation of the climate chamber temperature is 0.1℃, and the relative humidity is±3%. 3) The time for the climate chamber to reach the stable detection conditions is different under different environmental conditions, those are 3.3 h, 7.8 h, 3.8 h and 4.4 h in spring, in summer, in autumn and in winter, respectively. Conclusion: With the proposed control method which applied to the 30 m³ climate chamber, the following conclusions could be drawn:1) There is no phenomenon of the fog and the condensation inside the climate chamber. 2) The accuracy of steady-state between 23±0.1℃ and 50%±3% inside climate chamber, which temperature and relative humidity respectively, meeting the ISO 16000-9 standard requirements; 3) The time for the climate chamber to reach the steady state is less than 8 h.

Objective: The relativity between physiology and biochemistry indexes of athletes and functional property of wooden sports flooring was carried out on the basis of the interactions between athletes and wooden sports flooring. A method has been established about comparing the functional property of wooden sports flooring through sports physiology and biochemistry indexes. Method: Three typical different samples of wooden sports flooring with different structures (the structure with double keels, the structure of single keel and the removable structure) were chosen as the tested objects. The exercising process was carried out under the same exercise pattern and two levels of exercise intensity (low exercise intensity when heart rate arriving 110-120 beats per minute, and high exercise intensity when heart rate arriving 170-180 beats per minute). The relative physiology and biochemistry indexes of the athletes were tested, including the immediate blood lactate concentration(BLC), Borg ratings of perceived exertion(RPE) and serum creatine kinase(CK). Then, the ANOVA analysis and non parametric analysis were used to judge whether there is a significant difference between the test values or not. Result: 1) Under the conditions of fixed exercise pattern, the structure of wooden sports flooring and the exercise intensity both have significant influences on BLC of the athletes. The BLC values of the athletes completing the fixed exercise on the wooden sports flooring of the structure with double keels are significantly higher than the values gathering from the other two samples, under the low exercise intensity. 2) The Borg ratings of perceived exertion(RPE)method is used to evaluate the status of athletes after completing the fixed exercises. The results showed that the athletes on the structure with double keels subjectively feel most tired under the low exercise intensity. The RPE results of this structure are obviously higher than those of the other two samples. 3) Under the conditions of fixed exercise pattern, the structure of wooden sports flooring and the exercise intensity both have no significant influences on CK. Conclusion: There are correlations between physiology and biochemistry indexes of the athletes and the functional properties of wooden sports flooring. The method about comparing the functional property of wooden sports flooring through sports physiology and biochemistry indexes is feasible. The method is that under low exercise intensity, the athletes complete the same continuously hurdling on the wooden sports flooring with different structures. Then the BLC and RPE would be tested. The BLC values are analyzed through ANOVA method or non-parametric Kruskal-Wallis test in order to judge whether there is a significant difference between the BLC values of the athletes who completing the exercise on different structures of wooden sports flooring or not. Then the order of the functional property of wooden sports flooring from high to low could be decided according to the order of RPE values from high to low too.

Pine wilt disease has a significant impact on the forest ecological health, which can lead to large-scale death of pine forests. Effective prevention of pine wood nematode disease is an important measure to maintain the forest ecosystem. Esteya vermicola is an endoparasitic fungus of Bursaphelenchus xylophilus, a pine wood nematode, and has potential as a biological control agent for pine wood nematode disease. In recent years, the research on this little-known fungal species has increased. Based on this, this article systematically introduces the bacteria from the aspects of its discovery, morphology, culture, infection mechanism, molecular level research and biological control applications. E. vermicola, a total of six strains, can produce two types of spores:lunate spores and rod-shaped spores. Moon spores can adhere to the surface of pine wood nematode and parasitize the nematode to kill nematodes. E. vermicola can survive in pine and in the resin secreted by pine, and attracts pine wood nematodes by producing the scent of host pine trees. The culture conditions have a great influence on the growth, sporulation, and spore invasion of E. vermicola. Glycine can be added to the medium to enhance its resistance to the environment. The genome of E. vermicola has been completely sequenced, and a serine protease gene with highly virulent to B. xylophilus has been cloned. Endophytic bacteria are also found in the cells of the strain, which can be detected by molecular methods. The application of biocontrol containing the fungi in different ways, such as trunk injection, canopy spraying and wound inoculation in the greenhouse and in the field, showed that it can reduce the infection of the pine wood nematode to pine wood. At present, the research on this fungus is mainly concentrated in the laboratory. There are also studies on the application of field prevention and control, but it is still relatively less. The research of this fungus in the future could be carried out in several aspects:1) molecular level research to clarify its infestation mechanism; 2) research on the commercial biological agent production of the fungus; 3) research on field prevention and control programs; 4) the research on the relationship between Monochamus alternatus and E. vermicola.

Objective: Picea crassifolia is the dominant native species in the northeast Qinghai-Tibetan Plateau, and thus is believed to be important in regulating regional soil and water conservation and carbon cycle. The objective of this research was to investigate the effects of mingling intensity on the dynamics of fine root biomass, morphological characteristics and their impact mechanism in P. crassifolia mixed natural forests. The result would provide a theoretical basis for forest rehabilitation and management in the eastern Tibetan Plateau. Method: A suite of mixed middle-aged P. crassifolia natural forests representing different mingling intensities (0, 0.2, 0.4, and 0.6) were selected in Datong, Xining, eastern Qinghai-Tibetan Plateau of China. Fine root biomass density, specific root length, specific root surface area, root surface area density, and root length density were analyzed from two soil depths (0-20 and 20-40 cm) by taking soil cores. Result: In the P. crassifolia forest of mingling intensity 0.4, the diameter class of 10-25 cm (63.72%), height classes of 24-32 cm (48.72%) and 16-20 cm (11.18%), accounted for the largest proportion of all trees, which are significantly higher than the forests with other 3 mingling intensities. Fine root biomass density was mainly distributed in 0-20 cm soil depth, accounting for 68.31%-83.49% of the total. Values of fine root biomass density in the soil depth of 0-20 cm increased with the increasing mingling intensity and peaked at the mingling intensity of 0.4 (616.26 g·m^-3) and then decreased in the mingling intensity of 0.6. Fine root biomass density in the soil depth of 20-40 cm increased with increasing mingling intensity, which peaked at the intensity of 0.6 (227.17 g·m^-3). Changes of morphological characteristics of fine root highly depended on the mingling intensity. Specifically, in the soil depth of 0-20 cm, root length density and root surface area density showed as mingling intensity of 0.4 > 0.2 > 0 > 0.6, while specific root length and specific root surface area showed as mingling intensity of 0.4 > 0.2 > 0.6 > 0. In contrast, in the soil depth of 20-40 cm, root length density, root surface area density and specific root length showed the same pattern as mingling intensity of 0.6 > 0.4 > 0.2 > 0, while specific root surface area showed as the mingling intensity of 0.6 > 0.2 > 0.4 > 0. With the increase of mingling intensity, contribution of P. crassifolia to fine root biomass density and morphology such as specific root length, specific root surface area, root surface area density, and root length density gradually reduced, whereas the contribution of Betula platyphylla to that increased in the soil depth of 0-40 cm. The effect of mingling intensity on fine root length density and root surface area density was mainly focused on the finest diameter fine roots (0-1 mm). Conclusion: In the study region of eastern Qinghai-Tibet Plateau, P. crassifolia mixed forest of mingling intensity 0.4 was characterized by proper ratio of height class and diameter class. Meanwhile, uneven-aged and multi-storied forest is benefit to reduce the competition among neighbor trees overlapping and promote the using of forest resources, and thus believed to improve the stability of the forest community in the long run. The amount of fine root biomass density, specific root length, specific root surface area, root surface area density, and root length density maximized at the mingling intensity of 0.4. The result suggested that future management of middle-aged P. crassifolia forest should appropriately control the mingling intensity of 0.4, at which growth of fine roots can be maximized and the utilization of forest resource can be promoted and thus achieving the goal of sustainable development of forest.