Objective: Litters decomposition is an important process for the material cycling and energy flow in ecosystems. The mixture of litter components will have a non-additive effect on the decomposition rate, i.e., the decomposition rate of mixed litter is higher or lower than the weighted average of the decomposition rates of all single components. The Rhododendron delavayi forests are important sightseeing resources in the Baili Azalea Forest Area in Bijie, Guizhou Province of China. The litters and humus layer of these forests exert numerous ecological services, such as soil erosion control, carbon sequestration, and water regulation.Especially, the flower has good pharmaceutical value. Collecting fresh flower litter during the flowering season is the main approach to use this pharmaceutical value. However, an urgentissue is to determine the rationalintensity of flower collection with a precondition of no obvious effect on litter decomposition so that the structure and functions of the humus layer can be maintained. In this decomposition study of the litter of R.delavayi, a dominant species of the azalea forests, the non-additive effect in the treatments with different flower-leaf ratios was quantified, a decomposition model was developed and used to simulate the decomposition response to the variation of flower-leaf ratio, and the rational intensity of flower litter collection was explored. Method: A one year field decomposition study was implemented in fixed plots with 420 mesh bags filled with mixed litter of 7 treatments. These treatments had a flower dry weight ratio of 0 (pure leaves), 10%, 20%, 30%, 40%, 50%, 100% (pure flowers). Each treatment had 60 repeats. The loss of litter mass was measured in every two months.A litter decomposition model was set up based on the Olson equation to illustrate the litter decomposition response to the flower ratio and decomposition time. Result: The remaining rate of mixed litter treatments decreased with rising decomposition time and flower ratio. For the flower ratios of 0, 10%, 20%, 30%, 40%, 50%, and 100%, the remaining rate after one year decomposition was 63.1%, 58.7%, 60.2%, 56.8%, 56.2%, 55.5%, and 55.2%. The decomposition rate in different time periods was the highest during the 0-61 days (0.054 g·d^-1), and then decreased to 0.017 g·d^-1 during the 62-183 days, then slightly increased to 0.024 g·d^-1 during the 184-306 days, but decreased to 0.005 g·d^-1 during the 70-365 days. A non-additive effect existed for the decomposition of mixed litter, and it promoted the decomposition in this study. For the treatments with the flower ratios of 10%, 20%, 30%, 40%, and 50%, the highest non-addictive effect was found to be 7.8%, 4.7%, 6.9%, 6.8%, 6.6% after the decomposition of 365, 365, 330, 310, 207 days, respectively. A litter decomposition model consideringthe non-additive effectwas well established, with a high determination coefficient of 0.987. Based on the model simulation, the highest decomposition rate after one year was 48% for the flower ratio of 80%. For the near natural flower ratio of 20% and artificially reduced flower ratios of 15%, 10%, 5%, and 0, the simulated remaining rates after one yeardecomposition were 60%, 61%, 62%, 64%, and 66%, respectively. After one year field decomposition, the mean remaining rates of the treatments with flower ratios of 10% and 20% (close to natural ratio) were 58.7% and 60%, are no significant difference between them; but both were significantly lower than that of the treatment of pure leaves. This means that when the remained flower litter ratio after the flow litter collection is not below 10%, the decomposition rate of the litter can be basically maintained at the natural level. Conclusion: The decomposition rate of the mixed flower-leaf litter of R. delavayi forests increases with rising flower ratio. The decomposition dynamics can be predicted accurately using the established decomposition model which considers the non-additive effect. The collection intensity of flower litter from the R. delavayi forests should not exceed one half of the natural flower litter for pharmaceutical use, so that the natural decomposition rate of litter and the natural structure and functions of the humus layer can be maintained.

Objective: The objective of the study was to investigate the effects of sulfur (S) and manganese (Mn) addition on the mineralization of recalcitrant organiccarbon (C) and temperature sensitivity (Q₁₀) from forest soil and mor-humus collected from Changbai Mountains, northeastern China, in order to provide a basis for predicting the responses of biogeochemical cycling of carbon to atmospheric sulfur deposition. Method: Soil and mor-humus samples were collected from montane forests (broadleaved Korean pine and Betulaplatyphylla-Populusdavidiana mixed forest) and tundra, and then pre-incubated at 25℃ for 90-days toremovethe componentsof active carbonthat can be easily decomposed, followed by addition of 2 mL solutionsrespectivelyof MnCl₂, MnSO₄, NaCl, and Na₂SO₄, and addition of equivalent volumeofdouble distilled water to the control treatment, and further incubated at 25℃ and 35℃ for a 30-day period, respectively. Respired CO₂ was periodically measured at day 1, 3, 6, 10, 15, 21 and 30 during the 30 day's period, cumulative mineralization of recalcitrant organic carbon, recalcitrant organic carbon mineralization rate and associated Q₁₀ were calculated. Soil and mor-humus collected at the end of incubation experiment were used for measuring soil microbial biomass using phospholipid fatty acid(PLFA) method. Result: The recalcitrant organic carbon mineralization rate, cumulative mineralization of recalcitrant organic carbon and Q₁₀ were not significantly different between MnCl₂ and NaCl treatments, and betweenMnSO₄ and Na₂SO₄ treatments(P> 0.05). The addition of S rather than Mn affected the recalcitrant organic carbon mineralization rate. Mineralization rate of soil recalcitrant organic carbon under the MnSO₄ treatment were significantly higher than those of the Na₂SO₄ treatment(P < 0.05). MnSO₄ and Na₂SO₄ addition significantly increased the cumulative mineralization of recalcitrant organic carbon of the mor-humus samples from Betula platyphylla-Populus davidiana mixed forest and the three soil samples(P < 0.05), whereas the MnCl₂ and NaCl addition did not. The addition of Mn and S significantly decreased Q₁₀ of soils collected from broadleaved Korean pine forest (P < 0.05), but not those of soils from B. platyphylla-P. davidiana mixed forest and tundra. The addition of MnSO₄ significantly increased total PLFAs of the mor-humus collected from broadleaved Korean pine and B. platyphylla-P. davidiana mixed forest and total PLFAs increased after the addition of MnSO₄ solution, especially for the tundra soil. Conclusion: Our results highlighted an effect of S rather than Mn on the mineralization of soil recalcitrant organic carbon in Changbai Mountains. Hence, we suggest that more careful studies of the influence of sulfur on organic carbon mineralization are required to determine biogeochemical cycling of carbon from the ecosystem where atmospheric sulfur deposition is still not declining.

Objective: Explore the effect of glyphosate herbicide application on soil physicochemical properties of Eucalyptus plantations and provide reference for the rational application of glyphosate. Method: Six experimental plotsin size of 20 m×20 m were set up in a 4a Eucalyptus plantations in the state-owned forest farm of Zhangzhou City, Fujian Province, 3 plots were applied with the glyphosate, and the other 3 plots were not. The glyphosate was applied to remove shrubs and weeds in May and September of 2015, 2016. The composition was41% glyphosate isopropylamine saline and water, formulated at a mass of 1:50, the dosage was 1 500 kg·hm^-2 every time. For the control plots, the glyphosate was not applied and manual weeding was used instead, other tending was kept the same as those for the treatment plots. Soil samples were collected in May 2017 to determine the glyphosate residues and soil physicochemical properties. Result: After application of glyphosate, the soil density of the layers of 0-10, 10-20, 20-40 cm was 1.23, 1.27, 1.34 g·cm^-3, which increased by 0.02, 0.02, 0.01 g·cm^-3 compared to the control. The total soil porosity was 49.79%, 48.23%, and 46.64%, which were0.49%, 0.32%, and 0.47% lower than the control plots, respectively. But the differences were not significant. Glyphosate residues were mainly concentrated in the surface layer of soil, and the residue of 0-2 cm soil layer was 4.43 mg·kg^-1 with significant difference (P < 0.05). The pH values in 0-2, 2-5, and 5-20cm soil layers were 5.26, 4.63, and 4.57, respectively, which increased by 0.90, 0.24, and 0.07 compared to the control plots, but the soil layers from 20-40 cm decreased from 4.53 to 4.34, a decrease of 0.19, and the difference between the two treatments was only significant in 0-2cm soil layer (P < 0.05). The electrical conductivity of each soil layer decreased, and the soil layers at 0-2, 2-5, 5-20, and 20-40 cm were 61.83, 42.77, 34.20, and 38.17 us·cm^-1, respectively, which were lower than the control plots by 4.27, 8.26, 9.20, 1.00 us.cm^-1, the differences were not significant.The soil electrical conductivity of the two treatments had different trends with the depth of the soil layer. The control plots showed a gradual decrease, while the treatment plots decreased first and followed by am increase. The content of organic matter in 0-2, 2-5, 5-20, and 20-40 cm soil layers were 40.38, 36.62, 28.08, and 18.99 g·kg^-1, respectively, which were 16.70, 9.90, 0.90, and 3.89 g·kg^-1 lower than those of the control plots, and only 0-2 cm soil layers was significantly different (P < 0.05). The available P content of each soil layer was increased to varying degrees. The soil layers of 0-2, 2-5, 5-20, and 20-40 cm were 5.29, 2.89, 1.51, and 0.93 mg·kg^-1, respectively, compared with the control plots, it was increased by 2.39, 0.98, 0.26, and 0.22 mg·kg^-1, and only the soil layer of 0-2 cm had significant difference (P < 0.05). The contents of total N, hydrolyzed N and total P decreased, but the contents of total K and available K increased, and the differences were not significant. Conclusion: After 2 years of application of glyphosate in the Eucalyptus plantations, the physical properties of the soil deteriorated but the impact has not yet reached a significant level. The glyphosate residual concentration was concentrated in the 0-2 cm soil layer, and the content was 4.43 mg·kg^-1, which was significantly different from the control plots(P < 0.05); The effects on soil chemical properties are mainly concentrated in the surface layer. The pH value of the 0-2 cm soil layer increased by 0.90, the organic matter content decreased by 16.70 g·kg^-1, and the available P content increased by 2.39 mg·kg^-1, which were significantly different from the control plots(P < 0.05).

Objective: In this study, five plantations of Phoebe bournei、Michelia macclurei、Schima superba、Cunninghamia lanceolata and Fokienia hodginsii in subtropical region of china were selected as the research objects.The mains purpose of this study aims to investigate effects of main afforestation species on gene abundance and community structure of soil nitrogen cycle-related functional microorganisms, and to elucidate the microbial driving mechanism of the effects of subtropical plantation species on soil nitrogen retention. Method: For five kinds of plantation growing on acidic red soil, we applied real-time quantitative PCR to characterize the abundance of nitrogen-fixing microorganisms(nifH)、nitrifying microorganisms(AOA amoA, AOB amoA)、denitrifying microorganisms(narG、nirK、nirS、nosZ)、fungi (ITS) and bacteria (16S rRNA) in forest soils, Phylogenetic analysis of AOA different terminal restriction fragments (TRFs) was performed by cloning and sequencing, and the community structure of AOA was analyzed using Terminal restriction fragment length polymorphism fingerprints.The soil nitrogen retention ability and microbial characteristics of each tree species plantation were studied. Result: 1) The pH values of the soils of the five plantations ranged from 4.63 to 4.82. Soil nitrate nitrogen content of S. superba and M. macclurei forest was significantly higher than that of P. bournei and F. hodginsii forest(P < 0.05). Soil microbial biomass of M. macclurei and S. superba forest was the highest in five plantations, while that of P. bournei and C. lanceolata forest was the lowest.Lignin and cellulose content in litter significantly inhibited soil microbial biomass; 2) There was no significant differences in the nifH gene abundance between five plantations forest, the AOA abundance of S. superba forest was significantly higher than that of P. bournei, M. macclurei and F. hodginsii foreest. The AOB abundance of S. superba forest was significantly higher than that of F. hodginsii forest, and the gene abundances of AOA and AOB in S. superba forest were the highest among the five tree species, Ammonia oxidizing microorganisms, AOA/AOB>2, AOA was dominant in quantity. There was no significant differences in gene abundance (narG, nirK, nosZ) of microorganisms involved in soil denitrification among five tree species, the nirS gene abundance of S. superba forest was significantly higher than that of M. macclurei, C. lanceolata and F. hodginsii forest. Fungal ITS abundance of P. bournei forest was significantly higher than S. superba forest, no difference in bacteria 16S rRNA gene abundance was found among five plantations; 3) Pearson correlation analysis indicated soil pH was positively correlated with AOB, narG and nosZ, and soil NO₃^--N content was positively correlated with AOA; 4) Phylogenetic analysis revealed that the AOA assemblages belonged to the Nitrosopumilus and Nitrososphaera, HpyCH4V restriction endonuclease was used to digest the PCR products of AOA and produced four TRFs, of which TRF-76 and TRF-165 are the two main fragment types. The relative abundances of TRF-76 and TRF-165 accounted for 54.88%-100% and 0-45.12% of the total fragments, respectively. The relative abundance of TRF-76 and TRF-165 was significantly different between tree species. Non-metric multi-dimensional scaling showed there were no differences in community structure of AOA among five forest soils (P>0.05). Conclusion: AOA is dominant in ammonia-oxidizing microorganisms and may play a dominant role in subtropical acidic forest soil nitrification.The gene abundances of AOA and AOB in S. superba forest are the highest among the five tree species, the nirS gene abundance of S. superba forest is significantly higher than that of M. macclurei、C. lanceolata and F. hodginsii forest, the AOA abundance of S. superba forest is significantly higher than that of P. bournei forest, which may increase the risk of nitrogen loss from forest ecosystem.There was no significant difference in AOA community structure between five forest soils. The AOA assemblages belonge to the Nitrosopumilus and Nitrososphaera.

Objective: In this study, we investigated variations in rooting capacity and endohormones levels of subcultured shoots during long-term successive subculture of Pinus massoniana, and analyzed the correlations between endohormones levels and rooting capacity, in order to reveal rooting mechanisms and provide a theoretical basis for establishing an efficient micropropagation technique of P. massoniana. Method: The subculture buds of glm-8 genotype, derived from the 26-year-old P. massoniana 'Tongmiansong' stands, with strong rooting ability were obtained from the subculture from 2014-2018, and used as experimental materials. The rooting capacity (rooting root and root number) and endohormones levels were observed in subcultured shoots at the 1^st, 3^rd, 5^th, 8^th, 10^th, 15^th, 20^th, 30^th and 40^th subculture, respectively. The correlations between rooting capacity and endohormones levels were analyzed using linear regression, and significant differences in rooting rate, root number as well as endohormones levels among subculture times were tested based on analysis of variance. Result: 1. Subculturing times significantly affected rooting capacity of in vitro shoots in P. massoniana. For subcultured shoots of initial generations, rooting rate was 83.1% and root number was 2.4. The rooting effect of shoots was the best after subculturing of 15~20 times, reaching rooting rate of 98.7% and root number of 6.9, while the rooting ability of shoots dramatically decreased after subculturing of 40 times, when the rooting rate and root number were 65.7% and 0.5, respectively. 2. The levels of endogenous indoleacetic acid (IAA), gibberellins (GAs), abscisic acid (ABA) and zeatin riboside (ZR) significantly changed during long-term successive subculture. Among them, IAA or GAs had relatively greater correlation with the rooting capacity than ABA or ZR. Results of linear regression analysis showed that there was a significantly positive linear relationship between IAA/GAs ratio and rooting rate or root number. 3. Under the treatments of exogenous naphthaleneacetic acid (NAA), IAA and/or GA synthetic inhibitor, paclobutrazol (PAC), rooting performances were significantly different among the three subcultured buds with significant difference in rooting ability. For shoots subcultured 35~40 days, exogenous IAA improved the number of adventitious root and the optimal performance of rooting was found with the application of exogenous 4 μmol·L^-1 IAA in the rooting medium. However, PAC was obviously inhibitive for rooting of subcultured shoots. For shoots subcultured 700~800 days, NAA of low concentration (1.2 μmol·L^-1) significantly promoted adventitious rooting, while both exogenous IAA and PAC inhibited the rooting of shoots, and the inhibitive effects increased with the concentration of IAA and PAC. For shoots subcultured 1400~1600 days, IAA and PAC separately enhanced root number and rooting rate, but there was a threshold value for both IAA and PAC regarding their promotive effects on rooting. The best rooting effect was observed on the medium containing 4 μmol·L^-1 IAA+4 μmol·L^-1 PAC, and rooting rate and root number increased 49.3% and 406.7% compared with the control (NAA) treatment, respectively. Conclusion: The rooting ability of subcultured buds of Pinus massoniana is different with different subculture time, and long term subculture results in the decline of rooting ability. Endogenous IAA and GAs levels are closely related to the development of adventitious root in P. massoniana, and they regulate the occurrence and formation of adventitious roots. To achieve the efficient and stable rooting performance, we suggest that exogenous growth regulators, NAA, IAA and/or PAC, added in the medium should be chosen according to the endogenous IAA and GAs levels in micropropagated materials with different rooting capacity.

Objective: Phyllostachys edulis leaves are small and easy to be curled, which increases the difficulty and error of area measurement. Our aim of this study is to build a quick, convenient and accurate measurement of leaf area for P. edulis. Method: We collected leaves from 7 provinces and classified the leaf shapes. The data of leaf length and leaf width, as well as leaf area measure by the scanner were used to build the leaf models. The root mean square error, chi-square test, chi information criterion and predicted precision were used to test the errors and the goodness of the models. Result: 1) According to the length-width ratio, P. edulis leaves can be divided into three categories, which are triangular leaves (length-width ratio ≤ 7.2), elliptic leaves (7.2 < length-width ratio ≤ 8.3) and slender leaves (length-width ratio ≥ 8.3), respectively; 2) Morphological correlation of P. edulis showed that the product of leaf width and length was the closest factor related with leaf area, with ahigh correlation coefficient of 0.993; 3) The Classified fitting model of P. edulis leaf shape was based on the product of leaf length and width, with the determination coefficient of 0.990 1, the root-mean-square error value of 0.159 6, the chi-square value of 10.368 1, the Chi information criterion value of -6 317.10, and the prediction accuracy of 97.73%, respectively. The prediction results were better than that of area measured bya leaf area meter and predicted by whole fitting. Conclusion: The leaf area fitting model based on leaf morphology classification can accurately predict the leaf area by measuring the length and width of P. edulis leaves. In this way, it can not only measure the leaf area more accurate than leaf area meter and the whole fitting method, but also measures fast and conveniently. This model solves the difficulty in measuring the leaf area of P. edulis.

Objective: Polyploid varieties have very good performance in phenotype, nutrient content and stress resistance. The method of polyploid breeding was used, hoping to overcome the difficulties encountered in current breeding of Phyllostachys edulis, and to create new germplasm resources of polyploid varieties. Method: The imbibed seeds of P. edulis after soaking were treated with colchicine of different concentrations at different durations for mutation induction. Seed hypocotyl expansion was used as the indicator for early detection of mutation, and then DNA content of these candidates was identified by flow cytometry. The morphological, physiological and biochemical comparisons between diploid and homologous polyploid were performed. Result: 0.5 g·L^-1 colchicine could induce chromosome doubling of bamboo seeds after swelling, and 5% induction rate could be obtained by soaking with 0.5 g·L^-1 colchicine for 72 h and 1 g·L^-1 colchicine for 24 h. The flow cytometry detected that the relative DNA content of tetraploid P. edulis leaves was 2 times of diploid. Compared with diploid, the stomata density of the epidermis of the tetraploid was significantly decreased, the size of the stomata was significantly increased(P < 0.05), and the plant height, leaf length and leaf width of the tetraploid bamboo increased significantly, and the photosynthesis of the tetraploid plants was higher. Conclusion: The treatment of swelled seeds with colchicine can successfully induce tetraploid for P. edulis, and there are significant differences in physiological and biochemical characteristics between the tetraploid and the diploid.

Objective: Variation of growth traits in 12 hybrid clones of Populus×euramericana in different environments was investigated to study the genotype by environment interaction. We screened superior genotypes that can be promoted for stable and high yield, summarized patterns of the interaction how varieties adapting to site conditions in the trials, and evaluated the discrimination and representation of the test sites. It aims to provide technical support for the follow-up work of the Populus×euramericana. Method: The test materials were 12 different genotypes of 3-year-old Populus×euramericana hybrid clones. Six test sites in Heishan, Luannan, Zhucheng, Yuncheng, Ningyang and Shishou were used in the trials. The tree height and DBH were measured, and the coefficient of variation and the mean were calculated for preliminary comparison. A mixed effect model was established using the ASReml-R package, and the predicted trait values were used to generate GGE biplots. Patterns of variation were analyzed and used to evaluate the test site and to select superior genotypes. Result: Overall, the variation is greater in DBH than in tree height, and the variation in Heishan and Shishou is larger. The statistics show that the growth traits of different genotypes behave differently under the same environment, and that the growth traits of the same genotype behave differently under different environments. The test by the mixed linear model shows that genotype, environment, and genotype-environment interaction have very significant (P < 0.01) effects on the tree height and DBH of Populus×euramericana in the early growth, and the effect brought by the block is also very significant (P < 0.01). The predicted values of the traits are extracted as GGE biplots, the fitting degrees are all above 80%, and the results are almost consistent with the actual situation. The GGE biplots show that the relationship between the environment of tree height and DBH is similar but not the same; there is crossover interaction in the tree height and DBH; the selected genotypes are 5, 7, 3, 4 and 9. Among them, genotype 4, 5 and 7 belong to a full sib family. The genetic material and provenance of the male parent have a visible effect on the performance of hybrid clones, and N146 is an excellent genetic material. Conclusion: 1) The tree height and DBH of Populus×euramericana in the early growth stage are highly variable in Northeast China and Central China; the growth traits of Populus×euramericana in the early growth stage are significantly affected by genotype and environment and their interaction. 2) From the information in the GGE biplots, selected genotypes are the genotype 7 with high yield and the highest stability of yield, the genotype 5 with high yield, and the genotype 4 with a yield higher than the average and a high yield stability. 3) It is suitable to grow the genotype 3 and 4 in Heishan and Zhucheng areas; it is suitable to grow genotype 5 in Ningyang and Shishou areas; it is suitable to grow genotype 7 in Luannan and Yuncheng areas.

Objective: The main objective of this study is to investigate the diversity and distribution of entomopathogenic fungi in the Western Sichuan Plateau. Method: The soil total DNA, sampled from the samples of 13 different altitudes in the Western Sichuan Plateau, was sequenced by illumina HiSeq sequencing. The composition of fungi community, the species composition of entomopathogenic fungi and their correlation with altitudes were analyzed. Result: 1) At the Phylum level, Ascomycota and Bassiodiomycota together accounted for more than 69% of each altitude sample, which was absolutely dominant. At the Genus level, there were significant differences in the relative abundance of pathogenic fungi among the 13 altitudes, and the most dominant genera were different at each altitude.2) The entomopathogenic fungi detected in 13 soil samples belonged to 18 genera of three families of Hypocreales, among which the dominant species of Clavicipitaceae was Metarhizium, the dominant species of Cordyceps were Isaria and Cordyceps, and the dominant genus of Ophiocordycipitaceae differed in different samples. 3) The ratio of Cordyceps and Isaria in the Hypocreales reached two peaks at 4 300 m and 3 700 m. Conclusion: The diversity of pathogenic fungi is rich and varies at different altitudes in the Western Sichuan Plateau. The entomopathogenic fungi are mainly distributed in three families of Ascomycota Hypocreales, among which the abundance of Cordycipitaceae is significantly different in different altitudes. The abundance of Cordyceps is located at the altitudes of 3 400 m to 4 300 m, while the abundance of Isaria is located at 3 400 m to 3 700 m, indicating that the abundance of Cordycipitaceae is comparatively higher at the altitude range from 3 400 m to 4 300 m.

Objective: This study aims to clarify the relationship between landscape patterns and population density and adulthood occurrence period of Monochamus alternatus, which may lay the theoretical foundation for formulating the technical measures to control the population of M. alternatus with landscape patterns. Method: With the method of landscape ecology, the population number of M. alternatus in Pinus massoniana stands in 4 townships of Shunchang County, Fujian Province was monitored by the trapping method. The occurrence period of M. alternatus adulthood was divided into three periods and time dynamic model was established. ARCGIS, ENVI and FRAGSTATS software were used to extract and divide the landscape information and calculate the landscape index. The correlations between the landscape index at the Class-level and the landscape-level and the population density and adulthood occurrence period of M. alternatus were analyzed. Result: A total of 139 321 M. alternatus were captured in the four study areas. The peak period (T) in Pushang Town ended the earliest, the peak period (P) and the late period (L) in Shuangxi Subdistrict ended the earliest, while Dagan Town ended the latest in these two periods. At the patch type level, the population density of M. alternatus was significantly positively correlated with the area of forest patch and the number of roads patch, and the correlation coefficient was 0.952 and 0.959, respectively. The population density of M. alternatus was significantly negatively correlated with farmland patch area (R=-0.963) and the division index of roads (R=-0.968). At the landscape-level, the total area of landscape was significant positively correlated with the population density of M. alternatus (R=0.970), and the population density of M. alternatus decreased with the increase of the landscape richness, with a correlation coefficient of -0.958. The density and aggregation of forest patch had an important impact on the different period of adult occurrence. The peak period of adult occurrence had a strong positive correlation with the density and area of road patches. The density and area of urban, farmland and water patches were negatively correlated with the occurrence period of M. alternatus adults, but the total area of landscape was significant positively correlated with the different occurrence periods of adults. Conclusion: The area of forest patch and the number of roads patch are significantly positively correlated with the density of M. alternatus, but there was a negative correlation between division of road patch and the patch area of farmland and the density in this species. The density of forest patch and road patch is positively correlated with the end time of thriving, peak and late period of M. alternatus, while the density and area of urban, farmland and water patches are negatively correlated. In general, landscape pattern cannot only affect the population density of M. alternatus, but also affect the temporal dynamics of the occurrence of the population.

Objective: In this study, efficient cellulose-degrading fungi to degrade surface fuel of Maoer Mountain plantation were screened for investigating the effect of cellulose-degrading fungi on forest surface fuel decomposition, so as to reduce the fuel accumulations in the forest and reduce the potential risk for forest fire. Method: In this study, the fuels in Larix gmelinii, Juglans mandshurica, Fraxinus mandshurica and Picea asperata plantations were collected from Maoer Mountain Experimental Forest Station of Northeast Forestry University. The fungi were isolated and cultured using the rose bengal chloramphenicol agar medium, and then Congo red staining was used to screen strains with high cellulase activity according to the cellulose decomposition index. Morphological and molecular identification were performed. The suspensions of different strains with high cellulase activity were inoculated into flasks with three kinds of decomposition substrates (coniferous, broad-leaved and broadleaf-conifer mixed) and then cultured in a constant temperature incubator for 80 days. Samples were taken regularly, and the content of holo-cellulose was determined for analyzing the cellulose decomposition rule. The strain with the most efficient degradation effect on natural cellulose in forest fuel was selected, which was verified by scanning electron microscope. The screened efficient cellulose-degrading fungi were used to prepare the fungal disks, which were put into the malt extract medium, and the shaking culture was performed for 5 days. The fungal suspension was used as a single microbial agent, and the mixed microbial agent was obtained by mixing two fungal suspensions with equal volume. The microbial agents were sprayed into litter bags with different fuels of J. mandshurica, L. gmelinii and their mix in low, medium and high dosages. Litter bags were collected each month to determine holo-cellulose content in the fuels, and analyze the degradation effect of different microbial agents on the holo-cellulose in fuels. Result: Among fifteen fungi selected by RBC medium, eight had high cellulase activity, according to the distinct hydrolytic circles they produced on CMC-Na medium. Fungus B2 (Cladosporium ramotenellum) had the highest cellulolytic index. Fungus A4 (Sarocladium strictum) had the strongest degradation capable of holo-cellulose in the three fuel substrates based on the cellulose decomposition result, followed by fungus A2 (Peniophord incarnata). Further, the scanning electron micrographs indicated that the mycelia of isolate A4 could adhere to the leaf surface and invade the leaf tissue to degrade holo-cellulose in leaves by secreting cellulolytic enzymes. The degradation rate of holo-cellulose in the three substrates with different dosages was higher than that of the control, and the order was high concentration, medium concentration, low concentration and control. The degradation rate of holo-cellulose in the three fuel substrates with microbial agents was as follows:microbial agent C(mixed microbial agent)> microbial agent B(fungus A4)> microbial agent A(fungus A2). Conclusion: Fungus A4 is a highly effective fungus selected in this study. It also has a strong degradation ability in the field test, and the mixed microbial agent constructed with strain A2 has a better degradation effect on the holo-cellulose in the fuels. The optimal conditions of enzyme production can be explored in the follow-up study, so as to realize the degradation of forest surface fuels to a greater extent.

Objective: Monitoring wetland vegetation is of great significance for the protection and management of coastal wetlands. In order to improve the monitoring effect of coastal wetland vegetation, this paper attempted to propose a more effective method. Method: A part of Hangzhou Bay coastal wetland in Cixi, Ningbo was taken as the study area. Based on high spatial resolution satellite images of QuickBirds, the method of combined fully convolutional networks (FCN) and object oriented was applied to monitor coastal wetland vegetation. The images were improved the spatial resolution by integrating the multispectral data and panchromatic data, the label maps were made by the way of artificial visual interpretation, the training samples were selected with a 100×100 window, then were flipped and rotated, finally 4 904 pairs of training samples and 544 pairs of test samples were prepared. The corresponding model parameters were applied to the whole image after the FCN model training is completed with samples, and the classification results of the whole image were obtained. Multiscale segmentation was performed on the original image, and the optimal segmentation scale was determined to be 170 by using the average global score index method. The classification results of FCN were bounded by the optimal segmentation results, and the final classification results were obtained and the coastal wetland vegetation classification map was made. The confusion matrix was used to evaluate the final accuracy. Accuracy evaluation was performed on the results from FCN and the results processed by the FCN combined with the object-oriented method. Result: The overall accuracy of image classification results from the FCN is 94.39%, the accuracy of the typical wetland vegetation is more than 85%. However, there is a phenomenon of "salt and pepper", the main reason for the error is that the background of the coastal wetland is complex, and the spatial distribution of different vegetation types is chaotic. The result image after combining the two methods reduces the salt and pepper, the overall precision is 97.56%, the accuracy of typical wetland vegetation is above 90%. Conclusion: The coastal wetland vegetation monitoring method based on the FCN could effectively extract the typical wetland vegetation information from the high resolution images. On the basis of this, combined with the object-oriented multi-scale segmentation method, it could effectively eliminate the salt and pepper, make up for the defects based on pixel classification, optimize the classification results of coastal wetland vegetation, and it is worthy of promotion and application in the monitoring of coastal wetland vegetation.

Objective: This study analyzed biochars pyrolyzed from urban green wastes of wood bark, branch, leaf and grass biomass in a bench pyrolyzer, in order to explore its value for potential application to urban soil and environment improvement in recycling green waste through biomass carbonization. Method: Physico-chemical, and elemental analysis of carbon and metals as well as nutrients, surface morphology and tomography analysis and proximate analysis of biochar particles, and GC/MS analysis of dissolvable organic matter (DOM) pool of biochars were conducted to characterize the organic composition, particle adsorption capacity and moisture retention, existence of bioactive molecules and potentially toxic metal elements (PTEs) of the biochars. Result: The organic carbon content of the urban green waste biochars varied from 46.8% to 76.1%. With high thermal value up to 30 MJ·kg^-1, wood bark and branch biochars contained higher organic carbon by over 20% than leaf and grass derived biochars. However, the leaf and grass biochars were rich in N, P and K nutrients, with higher porosity and surface area, than the wood and branch ones. DOM pool of the biochars ranged from 2.86 to 31.20 g·kg^-1, with totally 177 chemical compounds, including organic acid, alcohols and saccharide. Contents of the PTEs were all beyond the guideline limits for organic amendments in agriculture. Concerning the significant content of PTEs, green waste biochars could not directly applied to agricultural soils, but meet the guideline limit for non-agricutural lands. Conclusion: The biochars from urban green wastes are rich in organic carbon with bioactive molecules, inorganic nutrients and micropores, but limited concentration of PTEs, indicating a great potential utilization use to improve urban soils. Particularly, the bark and branch biochars could be used as biomass fuels or water-absorbing materials, while the leaf and grass derived biochars could be applied as soil conditioner and nutritional growth media for enhancing urban vegetation. Furthermore, the bioactive components from leaf and grass would be expected to be used as foliar conditioners for plant growth in urban green zones.

Objective: This study explored the effects of different combinations of inorganic salts and hormones induced to agarwood and its mechanisms in Aquilaria sinensis, with the aim to effectively promote agarwood formation. Method: Uniform test design was used to deal with ten-year-old trees. NaCl, FeSO₄, CaCl₂, methyl jasmonate and ethephon were selected as the induction factors, and each factor covered 3 levels, totally 5 induction treatments. The content of starch, soluble sugar, alcohol soluble extract and the discoloration range of stem wood were determined, and histochemical and inclusion changes were, respectively, observed by optical microscopy and scanning electron microscope(SEM) through wood core samples that taken 0.5, 1, 3, 6, 10 months after treated. Result: 1) With the increase of induction time, the content of starch firstly decreased and then increased, and the time to reach to the lowest value was different between different treatments. While the content of soluble sugar was opposite, which firstly increased and then decreased, and the peak values were reached all at the 6th month. 2) It was found that the content of lipid substance in the ray cells, axial parenchyma cells and vessel of each treatment increased with time. 3) Wood parenchyma tylosis accumulated into adjacent vessel through half bordered pit between the vessel and parenchyma cells until complete blockage. 4) The effect of each treatment on the lateral discoloration range of wood core was not significant, but the length of the longitudinal discoloration was longer. The longitudinal discoloration length of treatment 2(0.5%NaCl+1.5%FeSO₄+0.1%CaCl₂+0.01%methyl jasmonate +0.05%ethephon)reached 77.0 cm after 10 months of induction. 5) The content of alcohol soluble extract increased with time, and the differences between different treatments were significant. Conclusion: 1) Among the five induction treatments, the optimal treatment was 0.5%NaCl+1.5%FeSO₄+0.1%CaCl₂+0.01%methyl jasmonate +0.05%ethephon, and the content of alcohol soluble extract reached 19.07% after 10 months of treatment. 2) NaCl and ethephon were the main factors to promote the aloes yield, and ethephon played a leading role. Theoretically, the optimum combination of agarwood induction was 0.16%NaCl+0.21%ethephon. 3) The lipids were firstly formed in parenchyma cells and then accumulated in vessel and parenchyma cells. The accumulation of lipids in the vascular was related to the changes of starch content in the parenchyma cells, the stronger the ability of starch transformed to soluble sugar, the more lipid accumulated and the more favorable for agarwood formed.

Objective: The purpose of this study was to explore the effects of bamboo moisture content, hot pressing pressure, glue consumption and hot pressing temperature on the mechanical properties of glued laminated bamboo after high-frequency hot pressing, and to optimize the processing technology of bamboos with better mechanical properties. Method: This research was carried out by orthogonal design of experiment, using the high frequency heating mode of processing, with phenolic resin (PF) as adhesive. The effects of four variables including moisture content, hot pressing pressure, glue consumption and hot pressing temperature on mechanical performance of bamboo integrated timber molded by high-frequency hot press were investigated, during which the measuring parameters included bending strength and shearing strength. By variance analysis and further establishing the mathematical model of bending strength and shearing strength, analysis of the mechanical properties of the optimal solution were analyzed. Result: Range analysis showed that the order of influence of thermal pressure parameters on bending strength was hot pressing pressure, moisture content, hot pressing temperature and glue consumption, while the order of influence of thermal hot pressure parameters on shear strength was glue consumption, moisture content, hot pressing pressure and hot pressing temperature. According to the main effect analysis, grade 4 moisture content, grade 1 hot pressing pressure, grade 1 glue consumption and grade 3 hot pressing temperature were hot pressing parameters for the best bending strength, and grade 1 moisture content, grade 1 hot pressing pressure, grade 2 glue consumption and grade 3 hot pressing temperature were hot pressing parameters for the best shear strength. The interaction analysis results showed that there was an interaction among the thermal pressure parameters. The analysis of variance showed that the hot pressing pressure was the most important factor influencing the bending strength of glued laminated bamboo, and the glue consumption was the most important factor influencing the shear strength of glued laminated bamboo. According to the mathematical model, the optimal solution of maximum bending strength was obtained:15% moisture content, 2.0 MPa hot pressing pressure, 260 g·m^-2 glue consumption, 130℃ hot pressing temperature, and the bending strength was 168.51 MPa. The optimal solution of shear strength was obtained:10.2% moisture content, 2.0 MPa hot pressing pressure, 240 g·m^-2 glue consumption and 130℃ hot pressing temperature, and the shear strength was 263.26 MPa. Conclusion: In this paper, our study showed that four parameters of moisture content, hot pressing pressure, glue consumption and hot pressing temperature have an effect on the mechanical properties of high-frequency hot pressing glued laminated bamboo. A mathematical model which can effectively reflect the influences of hot pressing parameters on the mechanical properties ofglued laminated bamboo is proposed. The mechanical properties of glued laminated bamboo produced by high-frequency hot pressing technology can meet the relevant standards and utilization requirements, and can provide technical reference for glued laminated bamboo molded by high-frequency hot pressing.

Wood multiscale structures are usually described at three different structural levels from nanometer to millimeter,including nanoscale polymer structure,microscale multilayer structure and macroscale growth ring structure. There were differences between these multiscale hierarchical structures,including the structures and properties of wood polymers; polymer contents and microfibril angles(MFAs)of different cell wall layers; cell types,sizes and arrangement orientation in growth ring structure. Those structure differences lead to differences in mechanical properties between multiscale hierarchical structure elements. Furthermore,the processes of wood fracture include crack initiation and propagation,which are related to structure and mechanical properties differences between multiscale hierarchical structure elements and irregular evolution of "natural defects". In this paper,the structures and mechanical properties differences of multiscale hierarchical structure elements,the effects of those differences on wood fracture were reviewed. Meanwhile,it should be studied from the following aspects in the future:1) The properties differences of wood micro- and nano-scale structure. Molecular deformations of wood polymers are revealed by the differences of arrangement orientation and response to load of wood polymers. The mechanical properties differences and stress transfer mechanism between wall layers due to the difference of wood polymers distribution and orientation of microfibrils in each layer of cell wall should be analyzed. 2) The crack initiation and propagation of growth ring and cell wall structure are studied,and cell fracture types of different fracture surface also are pointed out. 3) The effects of structure differences between multiscale hierarchical structure elements on the stress distribution and stress concentration of wood growth ring and cell wall structures are analyzed that will be revealed the influence mechanism of multi-scale structure difference on wood fracture.

Objective: The direct and indirect effects of the Grain for Green project on the income of households at different poverty levels were analyzed to explore whether the project can effectively improve the income of households at different poverty levels and alleviate rural poverty in the project area,and to understand the mechanisms that the project influences household income,in order to provide a scientific basis for a long-term mechanism of ecological poverty reduction by the project. Method: Based on the survey data of Chinese household income in 2013, excluding samples of urban household and migrant population,and provinces where the project was not implemented,a sample of 7 150 rural households was retained and an endogenous switching regression model (ESR) was used to construct the "counter factual" analytical framework. The average treatment effect of participation in the land conversion project on the household income of farmers at different poverty levels was estimated respectively to test whether the land conversion project can effectively improve the income level of households who made land conversion. Based on the type of income,the direct and indirect effects were further analyzed of the project on the household income of farmers with different levels of poverty,therefore clarifying the mechanisms the impacts of the land conversion project on the income of households who made the land conversion. Result: Based on counterfactual assumptions,in terms of overall household income,participating in the conversion project significantly increased the family income level of general poor farmers and severely poor farmers,and the income increase of severely poor households was more obvious; The direct effect of the project on household income was shown as follows:compared to the counter factual,the per capita transfer income and per capita operating income of severely poor peasant households participating in land conversion increased by 15.9% and 18.6% respectively; The indirect effects of the project on the income of households at different poverty levels were shown as follows:the per capita wage income of non-poor households,general poor households and severely poor households increased by 4.0%,7.9% and 24.6% respectively. Conclusion: The project has increased the family income of general poor farmers and severely poor farmers. Among them,per capita transfer income and per capita operating income have a direct impact on the family income of severely poor farmers. Per capita wage income has a positive indirect effect on households at different poverty levels,and as poverty deepens,the indirect effect grows. Therefore,the implementation of policies for differentiated subsidies for households at different poverty levels and training on knowledge and skills for employment in non-agricultural production can make more effective and rational use of the project funds. It provides a useful idea for the project to achieve the goal of income increase and poverty alleviation,and to establish a long-term mechanism for poverty alleviation.

Objective: Emission-control enterprise(ECE) is not only one of the vital participants in carbon emission trading,but also the key party demanding for forest carbon sink (FCS) in the carbon market. Studying the process of forming the demands for FCS,and important influencing factors of ECE's demand willing of FCS is of great significance to scientifically guide the ECE to choose the way of emission reduction,to realize market and ecological forest ecological compensation. Method: Based on the framework of Theory of Planned Behavior (TPB) and Enterprise'Natural Resources-based views,this paper illustrates theoretical foundation and deep logical relationship of the influencing factors with behavior attitude,subjective norm and behavior control in ECE's demand willingness of FCS under the carbon emission trade,constructs a theoretical model of the demand willingness of FCS of ECE,uses 396 ECE's data to identify the important influencing factors with Heckman two-stage model. Result: Most of the ECEs will use FCS as much as possible on the premise that they are willing to choose FCS. Manager's environmental view,green enterprise'culture,double advantages,partnership,emission reduction cost,policy support have significant effects on the choice of FCS in ECE; while manager's environmental view,double advantages,partnership,emission reduction cost,policy support,consumer have significant effects on the demand degree of FCS in ECE; manager's environmental view,double advantages,partnership,emission reduction cost,policy support as the vital factors of FCS's demand willingness in ECE. Conclusion: From the perspective of managers' environmental ethics,stakeholders and enterprise emission reduction stress,this paper provides a new theoretical explanation for the formation process of FCS demand willingness in ECE,broadens the applicable scope of planned behavior theory in enterprise green emission reduction research,and provides theoretical reference and management enlightenment for increasing choice of FCS and promoting the realization of FCS market value in ECE.

Objective: The relationship between wind load and wind speed of trees under different arrangement modes was studied,and the flow field characteristics behind trees were analyzed in order to find out the wind load and flow field characteristics when there is mutual interference among trees,and then provide a basis for tree protection and wind resistance. Method: The relationship between wind load and wind speed of a single tree,a row of trees and a column of trees was studied through wind tunnel test. At the same time,the flow field characteristics of specific plane behind a single tree and a row of trees were studied. Result: The resistance and overturning moment of the trees in the three arrangements increase with wind speed in a power way; The force of trees under a row arrangement was slightly less than that under a single arrangement,but the difference between the two decreased with the increase of wind speed; The force of the trees in a column is significantly reduced,and the resistance value is only 1/3 of the single arrangement; The resistance coefficient and the overturning moment coefficient of trees under the two arrangement modes of a single tree and a row decrease with wind speed in a power way; The resistance coefficients of trees in a column arrangement are almost independent of wind speed,while the overturning moment coefficients increase approximately linearly with the increase of wind speed; Under the incoming wind speed of 10 m·s^-1,the minimum relative wind speed in the cross-wind planebehind the tree is 0.47,and the maximum relative turbulence is 2.1. The isolines of relative wind speed and relative turbulence are radial distribution centered on the tree crown. The minimum value of relative wind speed and maximum value of relative turbulence are 0.42 and 2.2 in the cross-wind direction plane behind a row of trees. The isolines of relative wind speed and relative turbulence are parallel zonal distribution centered on the tree crown. The isolines of relative wind speed and relative turbulence in the downwind plane behind the tree under the two arrangements are elliptical centered on the tree crown. Conclusion: The wind load of trees increases as a power function with the increase of wind speed,but different arrangements will affect the wind load of trees. When the wind speed is the same,the resistance and overturning moment of trees under the three arrangement modes of a single tree,a row and a column decrease in turn. There is a wind-affected zone on the leeward side of the tree,and the flow field characteristics of this zone will change significantly,which is reflected by the decrease of wind speed and the increase of turbulence. When a single tree is arranged,the wind-affected area of the tree is a radial area centered on the canopy,and the wind-affected zone of the tree is a relatively continuous zone when arranged in a row.

Objective: This study aims to explore the effects of rainfall and irrigation on the particulate matter on leaves that grow in the lowest part of the canopy of poplar,and analyze whether the rainfall affects the physiological traits of leaves to provide a basis for the research and development of urban forest air pollution mitigation capacity improvement technology and the in-depth understanding of the interaction between tree physiological activities and atmospheric particulate pollution. Methods: Full drip irrigation(DIFI) treatment with the control(CK) were conducted in the experiment,and in each treatment,5 trees were selected as the sample trees. Two branches were selected from the lowest part of the canopy of each tree for two experimental treatments:(i)rainfall exclusion; (ii) no rainfall exclusion. Leaves on the two branches were used to measure. Results: 1) The retention quality of all types and diameter PM in DIFI treatment was slightly higher than that in CK treatment(except for water-soluble PM_2.5-10),but there was no significant difference(P>0.05). 2) The long-term cumulative retention quality of PM of each type and diameter size on the leaves per unit area under no rainfall exclusion treatment was slightly lower than that of the leaves under rainfall exclusion treatment,but there was no significant difference (P>0.05). 3) The quality of the wax layer on the leaves and the PM in the wax layer significantly decrease at the end of the experiment(P < 0.01),but there was no significant difference between the two treatments(P>0.05). 4) At the middle and the final stage of the experiment,the stomatal conductance of the leaves under no rainfall exclusion was significantly lower than that of the leaves under rainfall exclusion(P < 0.05). And at the final stage of the experiment,the midday leaf water potential of the leaves under no rainfall exclusion was significantly lower than that of the leaves under rainfall exclusion(P=0.032).After rainfall(no rainfall exclusion),although the net photosynthetic rate(P_n),transpiration rate(Tr),and water use efficiency(WUE) of the leaves did notchange significantly(P>0.05),P_n and WUE had a decrease trend,while Trdid notalways show the trend. Conclusions: At the leaf level,irrigation has a small effect on the retention of the particulate matter on leaves of Populus tomentosa,and rainfall can wash away larger diameter particulate matter on leaves to a certain extent. The increase of foliar particulate matter can significantly improve the stomatal conductance of P. stomentosa, thus affect its gas exchange rate.

Objective: Rhagoletis batava obseuriosa(RBO) is one of the major fruit borers of sea buckthorn. There are some limitations in using attractant or pesticide alone have limitations to control the RBO adults,thus the microsphere techniques were used to embed pesticides and attractants into microspheres in order to attract and kill the RBO adults,and prolong their effectiveness period in the field. Method: Gelatin and polylactic acid were used as the wall materials of microspheres,and spinosad and ammonium carbonate were used as the core materials. The microspheres containing the insecticide and attractant were prepared by the solvent evaporation method. Since ammonium carbonate is water-solubile and spinosad is oil-solubile,a water-in-oil- and then in-water(W1/O/W2) double-emulsion method was used to encapsulate the attractant and the insecticide. A single factor experimental design was adopted by taking different quantities of ammonium carbonate as variable,and polylactic acid,spinosad,gelatin and reaction temperature as fixed value,to evaluate the influence of different ammonium carbonate contents encapsulated in the microspheres on the physical and chemical properties of the microspheres. Infrared spectroscopy was used to detect if spinosad and ammonium carbonate were successfully embedded in the microspheres. The spinosad contents in the microspheres were determined using HPLC(High Performance Liquid Chromatography),and the ammonium carbonate content could be calculated by measured the N content within a sample using the Kjeldahl apparatus. Dialysis bag techniques and HPLC method were used to evaluate the release rates of spinosad from the microspheres. The quantities of ammonia released from the microspheres were evaluated every day by using an ammonia detector. The morphology of the microspheres was checked by the scanning electron microscope. The sizes and the span index were measured using a laser particle size analyzer. The attractiveness and lethal effect of the microspheres on the RBO adults were studied by bioassay. The microspheres were also sprayed in the field by the drone to test their control of the RBO adults. Result: The result of the infrared spectroscopy test showed that both the spinosad and the ammonium carbonate were successfully embedded in the microspheres. With increasing the quantities of ammonium carbonate,the quantities of spinosad and ammonium carbonate encapsulated in the microspheres firstly increasing then decreasing. The release of spinosad from the microspheres was able to last for 15 days,which was longer than the release time by the given same quantity of pure spinosad 7 days. The release of ammonium carbonate from the microspheres could last 14 days,also longer than that by the same quantities of pure ammonium carbonate only 6 days. Therefore,the prepared microspheres could fulfil the objective of prolonging the release period of insecticide and the attractant. The microspheres prepared by the different ammonium carbonate contents were spherical and dispersed,with uniform size,porous surface. The average diameter of microsphere was about 60 μm. There were significant differences (P < 0.05) in the attractiveness and lethal effect between the four kinds of ammonium carbonate content microspheres and the control,indicating that the prepared microspheres had attracting and killing ability to the RBO adults. Compared with the control,the population densities of the RBO decreased by about 76.13%,and the damage rates of the sea buckthorn fruits decreased by about 75.38%. Conclusion: The spinosad and ammonium carbonate have been successfully encapsulated into the microspheres,and both embedded compounds had continuous release effect. The prepared microspheres have the attractive and lethal effect on RBO adults,and could be used for the control of RBO.

Objective: This paper aimed to study ablation mechanisms on the surface of limber processed by water-jet guided nanosecond laser,and to discuss the influences of laser power and cutting speed on cutting width,with or without water-jet guided system. Additionally,it aimed to obtain the relationships of laser power,cutting speed and cutting width,and to analyze the influence factors of the surface quality of Korean pine. Method: On the basis of introducing test bench of water-jet guided nanosecond laser,the ablation mechanisms on the surface of Korean pine processed by water-jet guided nanosecond laser was researched,and the coupling mechanisms of water jet and nanosecond laser on the surface of the Korean pine was deeply analyzed; the experiment of water jet-guided nanosecond laser cutting Korean pine was carried out; Korean pine was used as the materials,the cutting width of Korean pine was repeatedly measured and average value was obtained. By adopting the method of single factor experiment,with or without water-jet guided system,the influences of different laser powers and cutting speeds on cutting width was discussed; the morphology of the surface of the cutting width was observed by scanning electron microscopy(SEM); the experimental data was processed through the multiple linear regression analysis by the IBM SPSS Statistics 23,and the predicted model was established. Result: Cutting width increased with the increase of laser power,and decreased with the increase of cutting speed. Without water-jet guided system,when the cutting speed of 50 mm·s^-1 and laser power of 6 W,minimum cutting width of Korean pine surface was 0.53 mm; with water-jet guided system,when the cut speed of 50 mm·s^-1 and laser power of 6 W,minimum cutting width of Korean pine surface was 0.31 mm. Through the observation of cutting surface morphology,without the water-jet assisted system,some residues were left on the inner walls of tracheids,and cutting surface was rough; with the water-jet assisted system,nearly no residues were left on the inner walls of tracheids,the cutting surface was smooth and the surface quality of Korean pine cutting was better. Through multiple linear regression analysis,the relationships of laser power,cutting speed and cutting width was obtained. The prediction model had a good prediction precision. Conclusion: The relationships between the process parameters and the cutting width should be controlled when processing water-jet guided nanosecond laser machining wood. When the cutting speed is larger and laser power is smaller,a minimum cutting width could be obtained. Compared with the without water-jet guided system,the surface quality of Korean pine with water-jet guided system would be better.