[Objective] We present a spatial-explicit model of seedlings establishment for scattered individual trees of Pinus sylvestris var. mongolica, which describes the spatial pattern of seedling recruitments. This study will provide a basis for prediction of expanding trend and natural regeneration of Pinus sylvestris var. Mongolica.[Method] A new spatial-explicit seedling recruitment model was developed based on the Von Mises distribution and Weibull distribution. The proposed model was calibrated by the least square method based on the measurement dataset of 1 374 seedlings from 10 scattered individual trees of Pinus sylvestris var. mongolica located at Hulun Buir sandy land in Northeast China. The proposed model simulated the spatial pattern of seedlings from an isolated Mongolian Scots pine with the base diameter of 70 cm.[Result] 1)The spatial pattern of natural regeneration for scattered individual trees of Pinus sylvestris var. mongolica followed the Janzen-Connell hypothesis but had the specific direction. The azimuth of seedlings had two zones of 0°-127° and 216°-360°, and the distance of seedlings to the parent tree was 0.37-10.95 m; 2)The spatial-explicit seedling recruitment model consists of seedling number modules, azimuth modules and distance modules. Derived from the model, we found the mean directions of seedlings dispersal were 16° north by east, and the mean distances of seedlings dispersal were 5.37 m; 3) The simulated spatial pattern of seedling recruitment agreed well with the observed ones.[Conclusion] The distances between seedlings and parent tree followed the Janzen-Connell's hypothesis, but their azimuth had the specific direction. The success of seedling establishment requires low radiation.

[Objective] The spatiotemporal differentiation and evolutionary trends of vegetation coverage in the border region of China, Laos and Myanmar (BRCLM) from 2000 to 2015 were discussed in order to provide support for scientific management and effective protection of vegetation in the region.[Method] Based on the time series of MODIS-NDVI in the BRCLM in recent 16 years, GIS,GPS,and Remote Sensing technologies in combination with statistics-related research method such as averaging, trend analysis,variation coefficient, Hurst index were used to investigate, the spatiotemporal pattern, evolution, variation and developmental trend in the future of vegetation coverage in the region.[Result] For NDVI annual mean,the maximum and minimum appeared in 2013 (0.779 4) and 2002 (0.725 9), respectively, it showed an increasing trend as a whole, with the growth rate increased by 1.05% every 10 years. Monthly average of NDVI showed a changing trend of "S" type with turning pointsin March and September. In addition, it ranged from 0.698 6 to 0.831 6 indicating a rising trend, with an average monthly growth rate of 0.50%. The vegetation coverage rate in the area was relatively high. Regions with 16-year average of NDVI larger than 0.6 accounted for 97.45% and most of which were concentrated in the mountainous areas where the tropical rain forest was distributed in succession. On the other hand,the areas with NDVI's average smaller than 0.6 accounted for only 2.55%, in which the main urban centers and peripheries in three countries, large areas of bare land in mountainous areas and along the Lancang-Mekong River Basin were the main areas. NDVI in the regions showed a decreasing trend with the increase of altitude. In addition, we found that the areas with high NDVI values (≥ 0.6) were mostly concentrated in the middle and low altitude areas below 1 500 m. From 2000 to 2015, the regions which NDVI time series showed improvement, degradation and stable accounted for 54.06%, 15.62%, and 30.32%, respectively, variation coefficient of NDVI time seriesranged from 0.024 4 to 0.468 8, and the spatial distribution was as follows:lower fluctuation region > low fluctuation region > medium fluctuation region > higher fluctuation region > high fluctuation region, the total proportion of low fluctuation region and lower fluctuation region was 78.49%. It was found thatregions with degradation of NDVI time series have obvious spatial consistency with those with large fluctuation, which mainly concentrated on construction land such as cities and towns, major traffic roads, and extensive bare land in mountainous areas. In terms of developmental trend in the future, the areas where vegetation coverage continue tobe the same trend as in the past 16 years accounted for 57.15%, and the areas with contrary trend accounted for 41.09%. Combined with the characteristics of spatial evolution, it was found that about 39.63%, 29.83% and 28.98% of the regions would develop in the direction of benign, unchanged and malignant in the future, respectively, while 1.56% of the regional development trend would be uncertain.[Conclusion] The vegetation coverage in BRCLM was generally good. In the past 16 years, the changing range of vegetation coverage in the area was relatively small.Andon this basis, it showed an increasing trend as a whole, the developmental prospects of vegetation were good. However, in the future, vegetation coverage in some areas with construction land and bare land would be degraded. Countries in the region should plan for economic development rationally, economical and intensive utilization of land resources, and carry out ecological restoration such as afforestation, converting the land for forestry and pasture according to local conditions to promote the healthy development of regional ecological environment.

[Objective] The Maxent model was used to evaluate the potential habitat of Firmiana danxiaensis in order to provide a scientific basis for in situ and ex situ conservation.[Method] A total of 186 distribution points data of F. danxiaensis in the yellow leaf stage were obtained by unmanned aerial vehicle (UAV). Combined with six environmental variables, the Maxent model was used to predict the potential suitable area of F. danxiaensis, and the impact of main environmental variables on its distribution was analyzed.[Result] The AUC values of the training set and the testing set were 0.947 and 0.906, respectively. The result of Jackknife test indicated that DEM, slope and aspect were the main environmental variables affecting the potential distribution of F. danxiaensis, contributing 51.2%, 30.3% and 7.8%, respectively. Under the joint influence of the three main environmental variables, F. danxiaensis was mainly distributed on the sunny slopes with an elevation of 150-530 m and a slope of 20°-60° in Danxiasha national nature reserve. The potential suitable habitat was divided into four grades:highly suitable, moderately suitable, less suitable and unsuitable by natural break method. The total area of high and moderate suitable area of F. danxiaensis was 30.27 km², accounting for only about 10.41% of the total area under study. The less suitable area was 41.01 km², and the unsuitable area was 219.5 km², accounting for 89.59% of the total area. The field survey data verified that 92.1% of field distribution points of F. danxiaensis fell into high and moderately suitable area, and the kappa coefficient was 0.958, indicating that the prediction accuracy of Maxent model was high.[Conclusion] The Maxent model can accurately predict the potential suitable habitat of F. danxiaensis in Danxiashan national nature reserve, and revealed the three main environmental variables that affected its distribution, indicating that the model has a good effect on small-scale regional prediction. Two suggestions were put forward for the protection of F. danxiaensis: 1) in terms of in situ conservation, it is necessary to strictly restrict the construction of tourist facilities in the highly and moderately suitable areas, and establish a long-term UAV remote sensing monitoring system to track the dynamic changes of the population; 2) in terms of ex situ conservation, reintroduction experiments should be carried out as soon as possible to expand their population distribution according to their suitable area. This study also verified the advantage and feasibility of low-altitude UAV remote sensing in species identification and population surveys, and revealed its potential application in the monitoring and evaluation of Danxia landform.

[Objective] To investigate the content, composition and origin of neutral sugars in rhizosphere and bulk soil under different thinning intensities, aiming at determining the changes of soil organic carbon pool and its stability after thinning.[Method] The experiment was conducted in a 30-years-old Pinus massoniana plantation. Four thinning intensities were performed with a randomized block design. Soil physicochemical properties and the content and composition of neutral sugar in litter and soil were measured to determine their responses to thinning.[Result] The content of neutral sugar in the rhizosphere soil was significantly higher than that in bulk soil, which was 4.55-7.89 mg·g^-1 and 2.67-4.18 mg·g^-1, respectively. Thinning significantly decreased the content of neutral sugar in the rhizosphere soil by 15.34%, 27.25% and 42.33%, respectively. The content of neutral sugar in the bulk soil was only decreased significantly in HIT. Thinning had no significant effect on the content of monosaccharides in the bulk soil, and its content was in the order of glucose > mannose > galactose > arabinose > xylose > rhamnose > fucose > ribose. The distribution of monosaccharides in the rhizosphere soil was consistent with that in the bulk soil, and its content was decreased with the increase of thinning intensity. Thinning increased (G+M)/(A+X) ratio in the rhizosphere and the bulk soil, and the ratio was greater than 2. The distribution proportion of neutral sugar in SOC in the rhizosphere and the bulk soil ranged from 16.65% to 17.36%, 16.75% to 23.21%, respectively, and the lowest ratio was found in MIT.[Conclusion] Thinning reduced the total amount of neutral sugars in the rhizopshere and the bulk soil, but showed no significant effect on soil monosaccharides content. Soil microbial activity was enhanced after thinning, leading to an increase in the microbial source of soil neutral sugars. The lowest ratio of neutral sugar to SOC was found in MIT, indicating that MIT benefited the stability of soil carbon pool. The thinning intensity of 45% was the better one for mature Pinus massoniana plantations.

[Objective]The purpose of this article is to explore the characteristics of temporal and spatial dynamic changes of vegetation coverage within Pisha sandstone area in Loess Plateau, to analyze the impact of the normalized difference vegetation index (NDVI) under different land use patterns,to discuss the spatial and time-delay relationship between vegetation coverage and hydrothermal factors. It provides ideas for the restoration and reconstruction of degraded vegetation within Pisha sandstone area in the Loess Plateau and the comprehensive management of the coarse sediment of the Yellow River. And it is beneficial to improving local living conditions and ecological environment in the Pisha sandstone area.[Method]Huangfuchuan basin was chosen as the study area, and a total of 192 MODIS13Q1 products between 2000-2015 were used to obtain NDVI values based on ENVI technique. Characteristics of NDVI in temporal dynamics and spatial distribution were investigated with methods of univariate linear Regression (ULR) and Spearman correlation analysis. Spatiotemporal characteristics under different land use types, the resolution of which is 30 m, was statistically analyzed and the responses of vegetation coverage to changes of precipitation and temperature factors during growing season was further emphasized.[Result]The average NDVI value of Huangfuchuan basin is ranged between 0.429 and 0.630, showing a linear increasing trend. The growth rate is 0.004 2·a^-1. Significant difference between the growing and non-growing seasons was detected, and the maximum value appeared in May. The temperature and precipitation also showed an increasing tendency with growth rates of 0.034 8℃·a^-1 and 6.27 mm·a^-1, respectively. Spatially, the NDVI values range between 0.1-0.3 in subbasin of Nalin, and in the range of 0.25-0.4 within subbasin of Shilichangchuan. The vegetation shows a spatial pattern of "high in gully and low on slope" in two subbasins. The NDVI values of different land types were all between 0.2-0.25. The NDVI values in different land use types ranked as forest > cultivated land > grassland > unused land. The growth rate in past 16 years ranked as grassland > unused land > forest > cultivated land. For tributary of Nalin, NDVI near the gully decreased by -0.09-0, while NDVI on slopes far away from the gully increased by 0-0.12. For tributary of Shilichangchuan, NDVI near the gully increased by 0-0.4 while by 0.04-0.12 on slopes. Over the whole basin, variation tendency of vegetation cover shows a spatial increase pattern of "very significant on slope surface nearly significant in the vicinity of gully,non-significant in gully ". During the past 16 years, there was no significant correlation between NDVI and temperature in the growing season. The correlation coefficient between precipitation and NDVI was -0.41~0.87. Compared with the vegetation near the gully, vegetation on the slope was more susceptible to precipitation. Vegetation has 1-year (P=0.036<0.05) and 1-month (P=0.001<0.01) lag time for precipitation, and 2-month (P=0.002<0.01) lag time for temperature.[Conclusion]Temporally, NDVI in Huangfuchuan basin showed a significant decreasing trend of fluctuations, and obvious distinction was detected between the growing season and non-growing season. Spatially, in accordance with the gully-slope distribution, the gully showed high NDVI but low increasing rate and even appeared the phenomenon of degradation; meanwhile, the slopes showed low NDVI but high increasing rate. NDVI with land use types of forest and grassland increased the most, indicating the validity of the returning farmland to forest projects. The correlation between vegetation and precipitation is high, and there is a certain lag.

[Objective] Quantitative understanding of the radial growth dynamics of Eucalyptus urophylla×E. grandis in the dry season and the influencing factors can provide data support and theoretical guidance for improving the wood yield of eucalyptus forest and its scientific management.[Method]The radial growth of 5.5-year-old E. urophylla×E. grandis in dry season was studied using a DC₃ radial change recorder (Ecomatik, Germany), and the environmental factors inside and outside the forest were simultaneously observed. The relationship between the radial variation in dry season and various environmental factors was analyzed.[Result] The results showed that, the radial diurnalvariation of stems in dry season showed regular period icfluctuation under the influence of factors affecting stem water balance. The daily maximum value appeared in the morning (9:00-10:00) and the minimum value appeared in the afternoon (16:00-18:00). The stems in rainy days continued to expand and then remained unchanged. The maximum value was about 2 hours later than that on sunny days. The radial cumulative growth of E. urophylla×E. grandis stems in dry season was a volatility rising process, which could be divided into three periods:relative stable period, rapid growth period and dehydration contraction period. During the whole dry season, the dominant environmental factors affecting stem radial growth were different in different periods. The soil water content and temperature (soil temperature and atmospheric temperature) were the most important factors limiting the growth of stems in the dry season.[Conclusion]The main influencing factors affecting stem radial growth of E. urophylla×E. grandis in the dry season were water and temperature. If appropriate measures such as increasing soil temperature and soil water content (irrigation, etc.) can be applied in the dry season, the growth of E. urophylla×E. grandis stems will promoted.

[Objective] Transplanting of tree peony seedlings si usually carried out in autumn. In recent years,with the expansion of cultivating area of tree peony Paeonia ostii 'Fengdan',large-scale late transplanting has appeared due to the lack of standardized transplanting technical guidance, resulting in poor plant growth, which directly affects the production efficiency. The purpose of this study is to explore the optimum transplanting period of tree peony 'Fengdan' seedlings and provide technological advice for itsrapid and high-yield cultivation.[Methods]Three-year-old seedlings of P. ostii 'Fengdan' were used as experimental materials. Eight transplanting periods were set up. The changes of root activity, leaf photosynthetic performance and biomass after transplanting were detected by a field comparison experiment, and the effect of different transplanting period son seedling formation wase valuated by principal component analysis and comprehensive evaluation.[Result]Transplanting dates were able to affect growth and development of new roots and shoots of the tree peony 'Fengdan' seedlings probably through environmental factors such as air and soil temperature, and soil accumulated temperature after transplanting. The timely transplanting significantly improved the growth and development of tree peony seedlings. There were differences in the total number of newborn roots, the number of lignified newborn roots, root activity, leaf area, leaf SPAD value, net photosynthetic rate, shoot thickness, root biomass, shoot biomass, total biomass, and seedling index of the seedlings among the 8 transplanting dates. The results showed that the number of lignified newborn roots, leaf area, root activity, net photosynthetic rate, biomass of seedlings transplanted in late September increased by 90.26%, 51.22%, 93.53%, 60.98%, and 46.00%, respectively, compared to those of seedlings transplanted in late November. Path analysis, principal component analysis and comprehensive evaluation showed the plants transplanted in late September grew best.[Conclusion]According to relationships between the biomass, seedling index, and environmental factors, the transplanting periods of tree peony 'Fengdan' seedlings could be divided into the optimum transplanting period (mid-September to late October, daily mean air temperature of 15-20℃), the relatively suitable transplanting period (the end of August to early September or the end of October to mid-November, 25℃ > daily mean air temperature > 20℃, or 15℃ > daily mean air temperature > 10℃), and the unsuitable transplanting period (before the end of August or later than late November, daily mean air temperature> 25℃, or daily mean air temperature<10℃).It is suggested that the rational production of tree peony 'Fengdan' should be arranged during the optimum transplanting period according to characteristics of local autumn climate, which lays a foundation for rapid and high-yield cultivation of tree peony 'Fengdan'.

[Objective] In this study, the photosynthetic characteristics of five bamboo species in rainy season were measured to investigate the differences in photosynthetic ability among different types of bamboo in rainy season in tropical areas, in order to understand the characteristics of different bamboo species, and provide a theoretical basis for the efficient cultivation of the bamboo species and their garden applications.[Method] Five bamboo species of Bambusa in Hainan Island were used as research materials. A LI-6400 portable photosynthetic apparatus was used to measure the daily variation, light response curve and CO₂ response curve. The influence of ecological environmental factors and the correlation between leaf morphological characteristics and photosynthesis were analyzed.[Result] 1) The net photosynthetic rate of different bamboo species varied greatly during the rainy season. The diurnal variation of the net photosynthetic rate of the five bamboo species all presented a "double-peak" curve with a typical photosynthetic "nap" phenomenon, and the first peak was higher than the second one. 2) The light response curve measurement showed that there were differences in the maximum net photosynthetic rate (P_max), light saturation point (LSP) and dark respiration (R_d) over the different bamboo species. B. tuldoides Munro and B. chungii McClure had relatively higher P_max and LSP, and lower R_d, and their photosynthetic ability was relatively strong. The net photosynthetic rate of all bamboos was higher in May-June, and lower in August-October. 3) The CO₂ response curve showed that there were differences in CO₂ compensation point (CCP), photorespiration rate (R_p) and carboxylation rate (CE) over the five species. The net photosynthetic rate of 5 bamboo species was higher in May-August, and lower in September-October. B. tuldoides had higher CE, R_p and A_max, and lower CCP and CSP, indicating that the photosynthetic capacity was strong, and was able to adapt to low light environment, while B. textilis var. Gracilis McClure was the opposite. 4) In rainy season, the net photosynthetic rate of five bamboo species was mainly restricted by stomatal conductance (G_s), transpiration rate (Tr), air temperature (T_a), photosynthetic active radiation (PAR), intercellular CO₂ concentration (C_i) and atmospheric CO₂ concentration (C_a). Studies on the leaf morphological characteristics of five bamboo species showed that the leaf area (LA) of B. ventricosa McClure and B. vulgaris 'Vittata' McClure was significantly greater than that of the other three bamboo species (P<0.05). The leaf thickness (LT) of B. ventricosa, B. tuldoides, and B. vulgaris 'Vittata' McClure was significantly greater than that of the other two bamboo species (P<0.05), and the specific leaf area was the opposite. However, there was no significant difference in the leaf dry matter content (LDMC) among five bamboo species (F=0.691, P=0.615). The correlations between P_max, A_max and LA, LT, LDMC, SLA were different among different bamboo species, among which the correlations between Pmax, Amax and LA were greater.[Conclusion] A comprehensive analysis of photosynthetic characteristics and leaf morphological structure of bamboo species shows that there is a certain correlation between photosynthetic characteristics and leaf morphological characteristics of bamboo species. The photosynthetic capacity of B. tuldoides and B. chungii is the largest, followed by B. vulgaris 'Vittata' and B. ventricosa, and B. textilis var. Gracilis is the smallest. B. tuldoides has strong photosynthetic adaptability and wide cultivation area. B. ventricosa has weak photosynthetic adaptation ability and narrow cultivation area. B. chungii is suitable for growing in areas with sufficient light. B. textilis var. Gracilis McClure can be cultivated under shady condition. B. vulgaris 'Vittata' is between B. textilis var. Gracilis and B. chungii, with high ornamental value.

[Objective] In order to comprehensively evaluate fast-growing, high-yielding and stability of Larix principis-rupprechtii families and discrimitiveness and representiveness of test sites, genotype main effect plus genotype-environmental interaction effect (GGE) biplot was applied to the analysis of 2017 annual growth data of the regional family trial.[Method] Based on the data of diameter at breast height (DBH) for 26 families of L. principis-rupprechtii at four experimental sites in north Hebei, three linear mixed effect models with the same fixed effects ("site" and "block at site") and the same residuals variance matrix (autoregression for row and column AR1×AR1,to be used for spatial effects analysis) were firstly fitted. A factor analysis model with two factors was used in random effects for Model 1 (FA model), while an unstructured matrix model (US model) was used in random effects for Model 2 (without measurement errors) and Model 3 (with measurement errors simultaneously). The optimal model was selected based on Akaike information criterion. Through the best linear unbiased prediction (BLUP), the BLUP data of DBH for each family at each site was obtained. Genotype main effect plus genotype-environmental interaction effect (GGE) biplot based on BLUP data of DBH was analyzed to evaluate families and sites.[Result] Model 3 (fitted by spatial effects with the unstructured matrix model including measurement errors (US model)) was selected as the optimal model based on Akaike information criterion. The sum of variance interpretation percentage for the first two principal components of GGE biplot based on BLUP data of DBH was 92.4%, which suggests that results were reliable. The four sites were divided into two groups. Group 1 included site L1 (Mayinggou of Chicheng), site L3 (Liutiaogou of Guyuan) and site L4 (Zhazi of Weichang), where family 111 had the largest DBH; while group 2 included site L2 (Yudaokou of Weichang), in which family 78 had the largest DBH. Site L3 (Liutiaogou of Guyuan) was relatively more effective in selecting families with characteristics of fast-growing, high-yielding and stability. The performance of each family varied at different sites. Overall, among the 26 families, family 111 had the largest DBH, followed by families 78, 72, 82, 76, 59, 100, 77, 56, 86 and 96. Family 1 had the smallest DBH, and the DBH of families 97, 116, 53, 35, 46, 66 and 49 were small too. The DBH of families 68 and 42 were close to the overall mean. Families 96, 86, 100 and 76 were fast-growing, high-yielding and stable. The stability of fast-growing and high-yielding families 111, 72 and 56 was moderate. The stability of families 78, 82 and 77 was below the average level. The fast-growing and high-yielding family 59 was unstable.[Conclusion] In this study, Model 3 (fitted by spatial effects with the unstructured matrix model including measurement errors (US model)) was more reliable than the other two models. Site L3 (Liutiaogou of Guyuan) with high discrimination and high representation can be used to effectively evaluate families. Families 96, 86, 100 and 76 with characteristics of fast-growing, high-yielding and stability can be widely promoted. GGE biplot based on BLUP data can be effectively used for evaluation of L. principis-rupprechtii families and test sites. This study can provide decision support for the selection and application of L. principis-rupprechtii families in north Hebei.

[Objective] Based on the modification for the Kozak equation, the easily measurable individual tree variables were used as the independent variables to develop the maximum outer crown profile model for Pinus sylvestris var. mongolica plantation. The purposes were to provide reference to study tree physiology, competition and crown surface area and volume of individual tree.[Method] The data of 907 largest branches which were selected from 70 sample trees of Pinus sylvestris var. mongolica by established 14 permanent sample plots in Heilongjiang Province were used. The Kozak model was modified to be used as the basic model to describe the crown profile of Pinus sylvestris var. mongolica, and the best model was selected to construct the nonlinear mixed effect model. The plot effect, tree effect and the effect of plot and tree were considered separately and two level nonlinear mixed effect techniques were used to develop the crown profile model. The package of nlme from R package was used to estimate the parameters of the model. AIC,BIC and -2LL were used to evaluate and compare models with different random parameters combinations, different variance-covariance structure and variance function. The best model was selected and the relationships between crown profile and tree variables were also studied. The dummy variable crown profile model for Pinus sylvestris var. mongolica was developed using forest density as the indicator.[Result] The results showed that the finial crown profile model of Pinus sylvestris var. mongolica included DBH, CR and HD. Compared with the basic model, the nonlinear mixed effect model included only plot effect or tree effect, showed significantly increased the fitting effect and the difference mainly sourced from individual tree. For the model employing only sample tree as the 1 level mixed effect, the model taking a₂, a₆ as the random parameters, diagonal matrix as the variance-covariance matrix, ARMA(1, 1) to explain the variance of within-group, power function to eliminate the heteroscedasticity was selected as the best model. The model with 2 level mixed effect had significantly increased the fitting efficiency compared to the 1 level mixed effect model. Using the two level mixed effect model, the relationship between the outer crown profile and tree variables were analyzed. The analysis was done under the situation where the other two variables were kept fixed and the crown radius increased with the increasing of DBH and CR. The crown radius of the upper and lower crown profile increased and decreased with the increasing of HD, respectively. The range of inflection points of outer crown profile was 0.625 0-0.917 0 and averaging 0.841 3. With the increase of suppress intensity, the inflection points moved to the crown base. The crown profile for the stand with the density less than 1 000 trees·hm^-2 was different from those between 1 000 and 2 000 trees·hm^-2 and larger than 2 000 trees·hm^-2.[Conclusion] The modified Kozak model which satisfied the biological reasoning, such that the crown radius equals to 0 at the tree tip and the inflection point was unique along the entire crown, has powerful advantages to simulate the outer crown profile of Pinus sylvestris var. mongolica plantation. 2 level nonlinear mixed effect model significantly increased the fitting efficiency of the model, and it can be applied into the maximum outer crown profile construction.

[Objective] The aim of this study is to provide a support for the study on the mechanism of wood degradation by Lenzites gibbosa (white-rot fungi) by sequencing the transcriptomes of white-rot fungus under woody and non-woody environments.[Method] High-throughput sequencing technology was used to sequence transcriptomes of mycelial samples of L. gibbosa with sawdust and non-sawdust treatments. The transcripts were compared and analyzed using such as eggNOG annotations, GO annotations, and KEGG annotations to predict and screen genes associated with wood degradation. Fluorescence quantitative PCR (qPCR) was used to detect the expression quantities of eleven genes such as mnp2 related to lignin degradation under 5 days of sawdust treatment, and the transcriptome data were used to analyze the genes' expression levels.[Result] A total of 38.9 Gb clean data were obtained from the transcriptome sequencing of L. gibbosa. The average clean data of each sample reach 6.49 Gb. The mapped ratio between the reads of each sample and the reference genome ranged from 71.23% to 74.25%. The edgeR software was used to analyze the genes' differential expression, and the results showed that 898 differentially expressed genes (DEGs) were obtained, among which 351 genes were up-regulated and 547 genes down-regulated. There were 251 genes annotated by GO database, 223 genes by KEGG database, and 704 genes by eggNOG database. eggNOG analysis showed that the expressions of DEGs were mostly clustered under the functional classifications of energy production and conversion, post-transcriptional modification, protein metabolism, chaperone relationship, biosynthesis of secondary metabolites, carbohydrate transport and catabolism. GO analysis showed that the significantly enriched biological processes with higher frequency were pyruvate metabolic process, isoprenoid biosynthetic process, aspartate family amino acid metabolic process and lignin catabolic process. In KEGG pathway analysis, the DEGs were distributed in 86 different biological pathways, and the major metabolic pathways with significantly enriched DEGs were carbon metabolism, citrate cycle, degradation of aromatic compounds, and glyoxylate metabolism. The result of qPCR showed that under the sawdust treatment the expressions of mnp2, mnp3, lip9, lip2, laccase1, and nadp were significantly up-regulated, and the expressions of mnp10s, mrp, cyp450-1, GroES1, and GroES2 were significantly down-regulated. qPCR and transcriptome sequencing showed that there was slight deviation in the difference multiples of expression, but the overall trend was consistent, which proved that transcriptome sequencing result were correct and reliable.[Conclusion] The wood degradation by L. gibbosa of is closely related to the pathways of carbon metabolism, degradation of aromatic compounds, and other biological processes such as lignin catabolic process. According to the result of genes functional annotation, 11 important differentially expressed genes related to the lignin degradation by white rot fungi were obtained.

[Objective] The community structure and diversity characteristics of soil nosZ-type denitrification microorganisms in the three kinds of primitive Pinus koraiensis forest (Picea koraiensis-Abies nephrolepis-Pinus koraiensis forest, Tilia spp. and Pinus koraiensis forest and Betula costata-Pinus koraiensis forest), Pinus koraiensis plantation and natural Pinus koraiensis secondary forest in Liangshui national nature reserve were analyzed to provide data support for a comprehensive understanding of the denitrification potential of different types of Pinus koraiensis forests and the nitrogen cycle process in the soil.[Method] The understory soils of five types of Pinus koraiensis forests were selected as the research object. The nosZ gene encoding nitrous oxide reductase (a key enzyme in the process of denitrification) of denitrification microorganisms was used as marker gene. The community composition and diversity characteristics of nosZ-type denitrification microorganisms in the soil were analyzed by high-throughput sequencing and bioinformatics analysis tequniques.[Result]The results showed that a total of 631 878 effective sequences of nosZ gene were obtained by high throughput sequencing from 15 soil samples in the five types of Pinus koraiensis forests, among which 579 871 sequences were high quality. These sequences were distributed between 178-383 bp but were mainly distributed around 260 bp. The main phyla of soil nosZ type denitrification microorganisms in five types of Pinus koraiensis forests were proteobacteria and bacteroidetes at the phylum level. However, the core genus included Burkholderia, Flavobacterium, Bradyrhizobium, Pseudomonas, Dechloromonas, Gemmatimonas, Achromobacter and Sinorhizobium. The analysis of alpha diversity of nosZ denitrifying microorganisms showed that the four alpha diversity index (Shannon, Chao1, ACE and Simpson index) of soil nosZ-type denitrification microorganisms among the five forest types were not siginificantly different, except that the Shannon and Simpson index of Betula costata-Pinus koraiensis forest was significantly higher than that of Pinus koraiensis natural secondary forest. Beta diversity analysis showed that there were significant differences in the composition of nosZ microbial communities in soils of five forest types (R=0.537,P=0.001), but there was no significantly different in the composition of three primitive Pinus koraiensis forests. Soil ammonia nitrogen and total nitrogen content were the main factors that significantly affected the nosZ type of denitrification microbial community (P<0.05).[Conclusion]There was no significant difference in the most alpha diversity index of soil nosZ-type denitrification microorganism, but beta diversity analysis showed that there were significant differences in the composition of nosZ microbial communities in soils of five forest types. The main environmental factors which influenced the composition and abundance of nosZ denitrification microorganisms over different forest types were soil ammonium nitrogen and total nitrogen.

[Objective] This study aimed to reveal the community structure and diversity of soil fungi and their impact factors in four habitats in Hulun Buir sandy land, and explore the influence of different habitats on soil fungi.[Method]The soil fungi in four habitats, including bare sandy land, grassland, Pinus sylvestris var. mongolica plantation and natural forest were selected as the research objects. The community structure characteristics of soil fungi were compared and analyzed by using field investigation, ITS high-throughput sequencing and RDA analysis.[Result]The results showed that 5 phyla, 22 classes, 73 orders, 28 families and 257 genera were detected in the soil samples of Hulun Buir sandy land. Among them, Ascomycota was the dominant fungal phyla in bare sand and grassland soil, and Basidiomycota was the dominant fungi in soils from P. sylvestris var. mongolica plantation and natural forest. There were 31 dominant genera in these areas. The dominant genera in soil from bare sandy land and P. sylvestris var. mongolica plantation were Mortierella and Cortinarius, and the dominant genera in grassland and P. sylvestris var. mongolica natural forest soil were Mortierella and Archaehorizomuses, Russula and Geminibasidium, respectively. The evolutionary branches of soil fungi from bare sandy land and grassland were more similar, while those from P. sylvestris var. mongolica plantation and natural forest soil were closer. The species richness and individual number of fungi from grassland were the highest and the distribution was the most uniform, followed by those in bare sandy land. The species richness, individual number and diversity index of soil fungi from natural and planted P. sylvestris var. mongolica forests were lower, and the distribution was more concentrated. Soil water content was the main impact factor affecting the distribution of soil fungal community. The distribution of dominant fungi was influenced by some environment factors. Soil porosity, soil water content, and soil organic matter were the dominant influencing factors of Mortierella, Archaeorhizomyces and Cortinarius, respectively, while total phosphorus was the dominant influencing factor of Russula and Geminibasidium.[Conclusion]The soil fungi in four habitats in Hulun Buir sandy land were mainly composed of Ascomycetes and Basidiomycetes. The evolutionary branch of soil fungi community structure from bare sand land was similar to that from grassland, while the evolutionary branch of P. sylvestris var. mongolica plantation and natural forest was similar. Various kinds of herbaceous plants increased the number of fungi and resulted in more even distribution of fungi. However, P. sylvestris var. mongolica reduced the number and variety of fungi to a certain extent, and made their distribution more concentrated. Different vegetation in different habitats influenced soil properties, and environmental factors such as soil moisture, nutrients and porosity directly affected the metabolic process and functional characteristics of dominant fungi in four habitats, resulting in variation in soil fungal community structure and diversity characteristics in the four different habitats.

[Objective] This paper proposes a method and technology for quantitative evaluation of the appearance quality of sawn timber, and explores the feasibility of digital detection and evaluation of the appearance quality of sawn timber in order to provide basic theoretical and technical supports for real-time online detection of appearance quality.[Method] An on-line detection system for surface defects of sawn timber, which consists a sealed darkroom, a light source, an industrial camera, etc., was established, and color images of the sample sawn timbers were collected under a stable light environment. Based on the image processing technology, the software experiment system was developed, which realized the detection and recognition of sawn timber defects. The detection and recognition rates of knot, hole and crack defects were 81.7%, 91.2% and 72.6%, respectively. The appearance quality evaluation model of knot, hole and crack was also established respectively. Based on these, a comprehensive quantitative evaluation method of appearance quality was proposed. The scientific value and feasibility of the method was verified by comparing experiments with national standards.[Result] By comparing the quantitative evaluation method with the grade index of sawn timber material, the linear correlation coefficient of the two is 0.85. The distribution of the comprehensive quantitative evaluation values corresponding to the grades of the sawn timber material grades 2 and 3 is relatively scattered, and the data between the grades is partially crossed. Besides, there is almost no crossover of the corresponding comprehensive quantitative evaluation value distribution between the other levels. By comparing with the grade index of sawn timber material, the linear correlation coefficient between the two is 0.88. The distribution of the comprehensive quantitative evaluation values corresponding to the grade 4 of the sawn timber material index level is relatively concentrated, and there is no data intersection with other grades. The timber material index grades are grade 1, grade 2, and grade 3. The distribution of the comprehensive quantitative evaluation values corresponding to the adjacent grades is relatively scattered, and the data between the grades is partially crossed. There is no intersection of data distribution between non-adjacent levels.[Conclusion] The research shows that the linear correlation between the comprehensive quantitative evaluation value and the grade of sawn timber material index determined, according to the relevant national standards, is relatively good. The linear correlation between the comprehensive quantitative evaluation value and the appearance quality requirements of the integrated timber board determined, according to the relevant national standards, is also relatively good. These lay the foundation for the digital detection and evaluation of the appearance quality of sawn timber. At the same time, by adjusting the relevant influence coefficient of the model, it can meet the needs of different tree species and different applications in order to achieve better evaluation result.

[Objective] In recent years, there have been few researches on the shear modulus test method for oriented strand board (OSB). It has been related to the acoustic emission method and the transverse vibration of the cantilever member to test the OSB shear modulus. This paper studies the OSB from the experimental aspect. Anisotropy, from the theoretical analysis and experimental aspects to explore the dynamic and static method for testing the in-plane shear modulus of OSB, involves the new concept of OSB free plate and cantilever plate shape coefficient, the principle of square plate static torsional strain method and its principle test implementation.[Method] Using ANSYS program to calculate the vibration shape coefficient of the OSB free plate and the cantilever plate test, it is given that the mode shape coefficient is dependent on the relational expression of length-to-width ratio and width-to-thickness ratio and verify the correctness of simulation calculation, dynamic test and static torsion test plate. The dynamic test of shear modulus about the OSB is made from a piece of the whole OSB board material, and the specimens were divided into three directions, namely, making specimen along the whole plate longitudinal(0° or x)direction, transverse(90° or y)direction and to the direction of 45° along with specimen longitudinal direction making. The test piece for testing the OSB shear modulus by square plate torsion test is made along the entire plate in the longitudinal or transverse direction. This study tests the dynamic elastic modulus of the OSB plate specimens about the longitudinal, transverse and 45° direction, and also tests the OSB plate specimen's dynamic in-plane shear modulus and shear modulus of 45° direction.[Result] The measured longitudinal elastic modulus of OSB plate is 2.89 times of its transverse elastic modulus, and the shear modulus of the 45° is smaller than that of in-plane shear modulus. It was given that the shear modulus through square plate torsion test which is suitable orthotropic material, and the calculation formula needs to use ±45°direction's difference of strain measurement value of the shear modulus calculation, for the OSB plate, the measured static shear modulus and dynamic shear modulus test very well.[Conclusion] The OSB plate's elastic modulus presents a direction tendency. The longitudinal elastic modulus is maximum, the transverse elastic modulus is minimum, and the 45° direction elastic modulus is the medium; the free plate torsional vibration shape method and cantilever plate torsional mode method are suitable for dynamic testing of OSB plate in-plane shear modulus, and its correctness is verified in square plate torsion test shear modulus; 0° and 90° OSB plate dynamic are measured almost equal, and can be used to estimate the OSB plate in-plane shear modulus value G_xy; OSB plate should not deal according to unidirectional composite processing, and in the theoretical analysis should be according to the orthotropic plate processing, OSB 45°direction of shear modulus G_45° < G_0° or G_90°; square plate torsion test for testing OSB in-plane shear modulus, should be in the center of the surface two square plate along the two diagonal paste ±45° degrees of strain gages, according to the difference of ±45° direction strain measurement calculation; shear modulus by dynamic test agrees with the shear modulus by square plate torsion test, which shows that the torsional vibration method is feasible in the test of OSB sheet shear modulus.

[Objective] To explore the main socio-economic drivers of forest transition and provide reference for promoting the coordinated development of regional socio-economy and forest ecology.[Method] Based on the remote sensing images and socio-economic statistics of 32 sample counties in Fujian Province from 2000 to 2016, this paper studies the impact of socio-economic and institutional factors on forest transition under different resource endowments by quantile regression method.[Result] 1) Farmer per capita income has a significantly positive effect on the growth of forest area, and in counties with moderate forest resources endowment, per capita income has a greater effect on forest transition, while in counties with rich or relatively low forest resources endowment, per capita income has a smaller effect. 2) Grain yield per capita has a significantly positive impact on forest area, and in counties with relatively low forest resources endowment, grain yield per capita has a greater effect on forest transition. 3) The collective forest tenure reform has a negative effect on forest transition.[Conclusion] Increase of farmers income and grain yield per capita is an important factor to promote forest transition in Fujian Province, which shows that raising the per capita income level in rural areas and promoting intensive use of agricultural land contribute to the restoration and growth of forest area. The reform of collective forest tenure system has a negative effect on forest transformation, which indicates that the collective forest tenure reform should be further improved to form a long-term incentive for forest farmers to invest in forestry.

Sex differentiation in angiosperms has a tremendous contribution to genetic diversity, offspring and environmental adaptation. Unisexual flower species, which are widely available in nature, play significant roles in economic development and social life, and their formation is an important way to avoid self-fertilization, promote cross-breeding, maintain genetic diversity and avoid sexual functional interference. The distribution of unisexual flower species in different evolutionary branches indicates that sex differentiation may be important in the evolution of genetic diversity and have a complicated regulatory network. Therefore, the study of the mechanism of sexual differentiation has vital theoretical significance and practical application value. Sex expression research involves morphology, biochemistry, cytology and molecular genetics. After reviewing the literature published in recent years, this paper presents a systematic summary of studies on sex differentiation from four aspects. 1) The formation of unisexual flowers originated from the ancestors of the bisexual flower, mainly through the two systematic evolutionary pathways of sexual organ loss or degradation. From the perspective of floral position and structures, unisexual flowers that have a variety of external morphological structures are divided into dioecy and monoecy. In terms of the flower development, the phenotypic characteristics of unisexual flowers are formed during four developmental stages, i.e., stage 0 (before the appearance of the sexual organ primordium), stage 1 (early development of the sexual organ primordium), stage 2 (pre-meiosis) and stage 3 (post-meiosis). The sex regulatory mechanisms of the species, which are involved in stages 0, 1 and 3, were discovered and proven. 2) Six major phytohormones, such as gibberellin, auxin and ethylene, play important roles in the regulation of sex differentiation. Gibberellin mainly promotes the development of stamens, while auxins, cytokinins and ethylene mainly promote the growth of carpels. The regulation mechanisms of related hormones has been elucidated, such as the ethylene synthesis pathway to regulate sex differentiation. 3) The molecular basis of organ loss or abortion has been investigated in different types of unisexual flowers. We integrated the sex-related or sex-determining genes in the identified species, and we explain the mechanisms of epigenetic regulation of sex formation, such as DNA methylation and small RNA, as well as the XY system, the X:A system and the ZW chromosome system, that are all used to regulate the pattern of sex differentiation. 4) Effects of environmental factors such as temperature, light intensity and mineral nutrition on sex differentiation. This paper presents a review of existing studies on sex differentiation in order to summarize different regulatory mechanisms of unisexual flower development, it deepens our understanding of sex expression, phylogeny evolution and regulatory mechanisms of sex differentiation.

Lignin is the second most abundant plant biopolymer on earth after cellulose. However, lignin is not used extensively due to its complex structures. Lignin micro/nano-particles can provide many opportunities for value-added applications of lignin. Self-assembly method of lignin micro/nano-spheres, which possess regular structure, include solvent and anti-solvent method, aerosol flow reactor and interfacial miniemulsion polymerization.When lignin and its derivatives are dissolved in solvent, such as tetrahydrofuran, dioxane and ethanol, and then dropped disionized water, the micro/nano-spheres can be formed. However, the micro/nano-spheres obtained through solvent and anti-solvent method may agglomerate in the drying process. Lignin precursor solution is directly atomized aerosol through aerosol flow reactor. When the micro/nano-spheres are prepared through interfacial microemulsion polymerization, lignin molecules will be linked by covalent and non-covalent bonded. Currently the micro/nano-spheres are mainly used in the fields of ultraviolet protection, drug carriers and nano-filler. When hydrophobic drugs are loaded by the micro/nano-spheres, the solubility of drugs in aqueous solution will be improved. And the loaded drugs exhibit the controlled release, a longer action time and a lower toxic and side effects. When photosensitive pesticides are loaded by the micro/nano-spheres, they display the characteristics of the controlled release and anti-photodegradation. The micro/nano-spheres are used to encapsulate the enzyme, which exhibit good stability and catalytic activity. Hydrophilic or hydrophobic outside surface of the micro/nano-spheres can be controlled through the change of self-assembly. Therefore, strong intermolecular interaction can be formed between the micro/nano-spheres and corresponding hydrophilic or hydrophobic polymer at the time of blending. In addition, the applications of the micro/nano-spheres have also been reported in the fields of adsorption materials, aggregation-induced emission nanomaterials and li-ion battery electrode materials. At present, studies on the micro/nano-spheres have been still in its infancy, there are much more to do. Because the interfacial miniemulsion polymerization can achieve synergies between non-covalent bond and covalent bond in the self-assembly process of lignin molecules, hollow lignin microspheres can be obtained by this method, which provides a new direction for the preparation of hollow lignin micro/nano-spheres. Moreover, light-emitting nanomaterials based on lignin may be as an important development direction due to the fact that lignin molecules have the characteristic of autofluorescence and aggregation-induced emission through J-aggregates.

[Objective] The suitable culture conditions for somatic embryos maturation and germination of Picea schrenkiana var. tianschanica were established to provide a basis for large-scale propagation and industrial production of somatic embryos of P. schrenkiana var. tianschanica.[Method] Embryogenic callus induced from mature zygotic embryos of P. schrenkiana var. tianschanica were cultured in 14 strains, 4 mature media and 100, 150, 200 mg fresh embryogenic callus. ABA concentrations (1.9, 3.8, 7.6, 19, 38 μmol·L^-1) were used for mature culture of somatic embryos, and the morphological characteristics of seedlings from different origins (somatic embryos, zygotic embryos and seeds) were compared. The optimum conditions for somatic embryos maturation and germination of P. schrenkiana var. tianschanica were selected. The somatic embryos were statistically analyzed using SPSS 18.0 and other statistical software.[Result] 1) 14 strains of P. schrenkiana var. tianschanica were used to induce cell embryos. The results showed that there were differences in the number of induced cell embryos among different strains on the same mature medium. Different strains and different quantity of embryogenic callus used for culture resulted in different number of induced somatic embryos. When the quantity of embryogenic callus was 100 mg, the number of edsomatic embryos induced of strain T36 was the highest (3 470±546), significantly higher than those of the other strains. 2) Mature somatic embryos of P. schrenkiana var. tianschanica were formed on all the 4 different media for maturing. The media with 1/2BLG+30 g·L^-1 maltose produced a higher number of somatic embryos than other media, at respectively 2 044(strain T6) and 2 282(strain T36), indicating a significant difference (P<0.05). 3) There was no significant difference in the number of imduced somatic embryos among different concentrations of ABA (P>0.05). When the concentration of ABA was 1.9-38 μmol·L^-1, the average number of somatic embryogenesis was 2 850-2 913, among which 7.6 μmol·L^-1 ABA was a better treatment. The average number of normal somatic embryos was 2 913, higher than that of the other treatments. 4) The germinating plantlets of different origins (somatic embryos, naked zygotic embryos and mature seed) were compared. The results showed that the seedling development stages of somatic embryos and naked zygotic embryos were basically the same. However, the plantlets of naked zygotic embryos were about twice as large as those of the somatic embryos, but there was no significant difference between them (P>0.05). There was no significant difference between somatic embryos and zygotic cotyledons (P>0.05). The number of cotyledons in most plantlets was 7-8.[Conclusion] The suitable condition for somatic embryos maturation of P. schrenkiana var. tianschanica was 100 mg embryogenic callus, 1/2BLG medium supplemented with 7.6 μmol·L^-1 ABA and 75% PEG4000, 30 g·L^-1 maltose, and added with 750 mg·L^-1 L-glutamine or 50 mg·L^-1 L-asparagine. In addition, there were differences in the number of induced cell embryos among different strains. Somatic embryos regeneration plant is similar in morphology to zygotic embryos plant, which can be used for large scale propagation and industrial production of somatic embryos of P. schrenkiana var. tianschanica.

[Objective] In this study, soil samples of Chinese fir plantations were collected to study the effects of biochar with different preparation materials and preparation temperatures on soil bacterial community structure and diversity through soil culture experiments in laboratory. The purpose of this study was to provide scientific basis for improving acid red soil in southern China and rational application of biochar.[Method]The V3+V4 region of 16S rDNA sequence of soil bacteria, amplified by PCR, was determined by high-throughput sequencing technique after 80 days of culture in the following different media:original soil with 3% Chinese fir leaf biochar produced at temperature of 300℃ (BL300) and 600℃ (BL600), original soil with 3% Chinese fir wood chip biochar produced at temperature of 300℃(BW300) and at temperature of 600℃ (BW600), and original soil only (served as control).[Result]The OUT-Wayne diagram analysis showed that the soil bacteria abundance with BL300 was higher than that of the control, while the abundance of other biochar treatments was lower. The results of PcoA analysis, Beta diversity analysis and UPGMA cluster analysis showed that the community structure and diversity of soil bacteria of fir leaf biochar treatment were significantly different from those of the control, among which BL600 was the most different from the control. The results of adding wood chip biochar were similar to those of control. The addition of biochar had a certain effect on the structure and function of soil bacteria at different species levels, among which the treatment of fir leaf biochar had very significant effect on the abundance of dominant bacterial species, and the treatment of the wood chip biochar had a relatively small effect on dominant bacteria.[Conclusion]The addition of BL300 biochar increased the abundance of soil bacteria, while other biochar treatments reduced the abundance of bacteria. Different raw materials and temperatures had effects on biochar. Because of the insufficient available nitrogen of fir wood chip biochar, the effect of Chinese fir leaf biochar on soil bacterial structure and diversity was more significant than fir wood chip biochar. The content of high-temperature biochar ash was more, so the influence on bacterial diversity was greater. Different soil bacterial populations have different living habits and functions, and the utilization degree of biochar components is different, so adding biochar can change the relative abundance of dominant populations in soil and the overall function of soil bacterial community.

[Objective] The wildland-urban interface (WUI) fires are increasingly frequent and cause serious damage to people's livelihood and economy. In this paper, a random forest (RF) model was used to spatially model the relationship between fire risk and its influencing factors in the WUI at the provincial scale, and the advantages of the random forest model in fitting and interpreting fire risk in the WUI were explored, and the influencing factors in the WUI fire were compared with the factors of forest fire risk to provide a basis for further assessment of fire risk in the WUI.[Method] Based on the historical fire data of Anhui Province from 2002 to 2011, in this study 9 factors from climate, geographical environment, human activities and social economy were designated as independent variables, and the monthly average fire density was used as the dependent variable. The feature selection method was used to obtain the contribution of different independent variables within the model, statistical characteristics and the average performance of the internal model, to select the independent variables into the final model. The random forest (RF) model was used to explain the fire risk of the WUI and analyze the important factors affecting fire risk in the WUI and Forest.[Result] The ranking of influence degree of key independent variables on fire risk in the WUI was Line density of roads, Line density of rails, Monthly average maximum temperature, Normalized Difference Vegetation Index, Population density and Elevation. The ranking on fire risk in the Forest was Monthly average maximum temperature, Normalized Difference Vegetation Index, Line density of roads, Line density of rails, Population density and Elevation. Through the training and calculation, it was found that the performance of random forest (RF) model in the five sub-models' training set was basically consistent with that of the test set. The simple correlation coefficient between fitted value and actual value reached more than 0.90, indicating that the RF model had remarkable ability to explain fire risk in the WUI and Forest. In addition, the RF model was fitted on the overall data set, and the correlation between fitted value and actual value of fire risk in the WUI was 0.997, and the correlation between fitted value and actual value of the forest fire risk was 0.996, indicating that the RF model had extremely strong fitting performance in the field of fire risk.[Conclusion] The most important independent variables that affect the WUI fire occurrence are the line density of roads and the line density of rails, while for forest fires, these variables are the monthly average maximum temperature and the normalized difference vegetation index. It is shown that the occurrence of fire in the WUI is closely related to human activities. Random Forest algorithm can show robust and extremely accurate fitting ability for fire risk in the WUI and Forest, which is a very useful tool.