Objective: Forest ecological compensation is an important measure to deal with environmental degradation and balancing regional development. Combined with the theory of forest ecosystem service flow and based on the direction of forest ecological benefit, horizontal compensation standards for forest ecological benefit from water retention service were studied in order to provide a scientific basis for improving the cross-provincial watershed forest ecological compensation mechanism. Method: Taking the Tingjiang (Hanjiang) river basin as an example, the equivalent factor method, water footprint method and gravitational model were used to study the overflow value of forest water retention services and their spatial transfer in the watershed under study to determine the compensation standards balancing the benefits between the receivers and the suppliers of compensation, Result: 1) The spillover value of forest water retention service in Longyan City, Zhangzhou City and Sanming City in the upstream area of the Tingjiang (Hanjiang) river basin was approximately RMB 804.49 million , RMB 58.57 million and RMB 130.38 million respectively. Guangdong Province should pay a total of about RMB 993.45 million in ecological compensation funds for water conservation to Fujian Province. 2) The region with the widest radiation area provided by Sanming City, Zhangzhou City, and Longyan City was Meizhou City, and Meizhou City undertook the main ecological compensation funds. 3) Longyan City received the most water-containing horizontal ecological compensation funds, accounting for 80.98% of the total compensation funds. The largest forest ecological compensation amount for forest water retention paid by Meizhou City, accounting for 88.89% of the total ecological compensation funds. Conclusion: The upstream areas of the watershed all have the spillover value of forest water retention services, with different radiation range and radiation amount to the downstream areas. The horizontal ecological compensation funds paid by the downstream beneficiary areas of the studied watersheds do not exceed 1% of the local GDP, which has good feasibility in compensation practice and it provides a scientific basis for the formulation of horizontal compensation standards for forest ecological benefits in watersheds.

Objective: In order to reveal the effects of forest succession and simulated warming on forest plant and soil autotrophic respiration rates and their coupling effects, we measured soil and plant root autotrophic respiration rates from the warming. The root respiration rates of different plant layers during the growing season were measured to analyze their responses to warming, intending to provide more data for the research on the response mechanism of forest soil carbon cycle to climate warming in the process of forest succession. Method: Four natural secondary forest types from Guandi Mountains were selected for the study, including poplar-birch broad-leaved deciduous forest, Pinus tabulaeformis conifer and broad-leaved mixed forest and Larix principis rupprechtii forest and Picea meyeri forest. Field fixed-point comparison test was used to simulate forest warming by building greenhouses on the forest floor. Root removal method was used to distinguish root respiration from the total soil respiration. We used Li-6400 portable CO₂ analyzer to measure the root respiration rates from 2016 to 2019 during the growing seasons. Results: The results showed that the warming increased the fine root biomass and carbon flux of total root respiration in the four forest types. Warming and its interaction with forest types significantly increased the root respiration rates of shrubs and herbs by 8.37%~15.26% and 10.88%~14.00%, respectively. As temperature increases the sensitivity of root respiration (Q₁₀) decreased. However, warming did not change the patterns of root respiration during each growing season. The fine root biomass and root respiration rates decreased with progress of forest succession while the temperature sensitivity of root respiration (Q₁₀) increased. Conclusion: Warming and its interaction with forest types did not significantly affect tree-root respiration rates. In contrast, root respiration rates of shrubs and herbs were significantly affected by warming, forest types and their interaction. With the increase of forest land temperature, forest root respiration rate increased, but its temperature sensitivity decreased, which indicated that the response of forest root respiration rate to temperature increase was complex.

Objective: This study aims to clarify the differences in biomass allocation in different plots, and reveal the pattern of biomass allocation and the dynamic changes in annual productivity through studying the effects of strip clearcutting on moso bamboo forest restoration, so as to provide a theoretical basis for evaluating the quality restoration level of the strip clearcutting stand. Method: In this study, three types of plots were set up, the plots with strip cutting by 8 m width (SC), and its reserved belts (RB) plots, as well as the traditional management forest plots as control (CK) . The productivity and biomass accumulation pattern of each component of bamboo in the different sample plots were investigated in 5 years after the cutting. Correlation analysis was performed to study the relationship between the component productivity and soil nutrient content in different plots. Result: In the on-year, the productivity of each component of bamboo in different plots was shown: bamboo culm>bamboo stump>bamboo root>bamboo branch>bamboo leaves. In the off-year, it was shown: bamboo root> bamboo stump>bamboo culm>bamboo branch. There was no significant difference in productivity between SC and RB and CK in the first year after cutting. In three years after cutting, the bamboo branch productivity in CK was significantly higher than that in SC and RB (P<0.05). In five years after cutting, the bamboo root productivity in RB was significantly higher than that in SC and CK, but the bamboo stump productivity in RB was significantly lower than that in SC and CK (P<0.05). The aboveground biomass accumulation of SC (73 357.74 kg·hm^?2) reached the level of CK (63 728.99 kg·hm^?2). Correlation analysis showed that the productivity of each component of bamboo was negatively correlated with the content of alkali-hydrolyzable nitrogen in the soil, and positively correlated with the content of available phosphorus. Conclusion: Strip clearcutting does not decrease the productivity of each component in the bamboo forest, and the productivity of each component in SC increases gradually with the recovery time, while the productivity of each component in RB increases first and then decreases. After cutting, the growth of new bamboo does not allocate more productivity to the aboveground part, and in 5 years after cutting, the biomass accumulation of SC could be restored to CK level.

Objective: Taking larch near-mature plantations (Larix principis-rupprechtii) in the core area of Chongli Winter Olympics as objects, this paper was carried out to discuss the selection method of target trees thinning and its effects on forest spatial structure in order to provide scientific bases for reasonable management activities making and plantation quality improvement. Method: Six sample plots with the area of 0.09 hm² (30 m × 30 m) were set up and measured. 125 tree · hm^?2 target trees were marked according to qualitative and quantitative indicators. Based on crown overlap and crown light competition height, the method of cutting trees selection was developed, which was used to select cutting trees simulated in 6 sample plots by setting different values of light competition coefficient( $ c $ ). Changes on cutting intensity were analyzed while those of target tree and stand spatial structure indexes under different c values were analyzed by using angular scale, mingling, crowding, intersection competition index, storey index and comprehensive index. Result: The cutting intensity of both tree number and basal area varied from 10% to 35% when the value of $ c $ ranged from 0 to 1, indicating the same trend of decreasing with the increase of value of $ c $ . The spatial structure of target trees was optimized by simulated tending thinning, and the improvement increased along with the increase of cutting intensity. The maximum increase of comprehensive spatial structure index was 45.50% when value of $ c $ was 0.6. The maximum improvement of angular scale and crowding were 17.93% and 46.83%, respectively, under $ c $ value was 0.7, while other spatial structure parameters reached the maximum improvement with the values of $ c $ is 0.6. Thinning also optimized the spatial structure of stand, and improved the isolation degree of tree species, light transmission conditions and competition level among trees in different degrees. Conclusion: The thinning intensity could be controlled by adjusting the coefficient of light competition using cutting trees selection method based on crown overlap and crown light competition height. The coefficient of canopy light competition could be used as a constraint for selecting cutting trees of crop tree management. However, the thinning objects and thinning methods should be determined according to the stand characteristics and operation requirements.

Objective: In this study, we investigated the response processes of leaf photosynthesis and carbon and nitrogen distribution of a poplar under elevated atmosphere CO₂ concentration and temperature, and explored the ecophysiological acclimation mechanism of the poplar to global climate changes, which would provide theoretical basis for promoting the long-term productivity and ecological benefits of poplar plantations in northern China. Method: The potted annual cuttings of a hybrid poplar (Populus × popularis ‘35-44’) were subjected to elevated CO₂ (+200 μmol·mol^?1) and/or temperature (+2 ℃) in OTCs for 4 months, and the changes of leaf photosynthetic traits, anatomical and stomatal traits, drymass and carbon and nitrogen distribution among organs were investigated. The ecophysiological responses of P. × popularis ‘35-44’ seedlings to elevated CO₂ concentration and temperature were discussed. Result: 1) Under elevated CO₂ concentration conditions, leaf stomatal density decreased and transpiration rate decreased, resulting in an increase of instantaneous water use efficiency. Leaf photosynthetic capacity and nitrogen use efficiency significantly increased. Nitrogen content per unit leaf area, instantaneous photosynthetic characteristics, and chlorophyll fluorescence characteristics remained unchanged through thickening leaf mesophyll, increasing root shoot ratio, C∶N ratio in leaves and roots, and LMA. However, the dark respiration rate per drymass decreased, and whole-plant drymass and total carbon content significantly increased. 2) Under the elevated temperature condition by 2 ℃, leaf stomatal density significantly increased, but instantaneous gas exchanges, chlorophyll fluorescence parameters and photosynthetic traits did not change. Plant height and whole-plant nitrogen slightly decreased, but organ drymass, carbon and nitrogen distribution maintained unchanged. 3) Under the treatment of both elevated CO₂ concentration and temperature, the carbon nitrogen ratio in roots was significantly lower than that of the treatment of increasing CO₂ concentration, while the photosynthetic nitrogen utilization efficiency was significantly increased. However, the increase in CO₂ concentration and temperature did not show an obvious synergistic effect. 4) CO₂ concentration and/or temperature treatments all decreased the stem drymass distribution percentage, but the stem C∶N ratio remained unchanged. However the treatment significantly changed C:N ratio in leaves and roots. Conclusion: P. × popularis‘35-44’ young cuttings can maintain leaf photosynthetic carbon fixation capacity by regulating leaf morphology, anatomy and C:N, which might be important under the declined nitrogen concentration induced by long-term elevated CO₂. Elevated temperature does not sharply change leaf photosynthetic traits, growth and carbon and nitrogen distribution. Elevated air CO₂ concentration and temperature do not have synergistic effect to the poplar cuttings.

Objective: This study aims to clarify the effects of different ammonium to nitrate ratios on nitrogen (N) uptake preference and traits of absorptive roots of coniferous and broadleaf seedlings, so as to provide scientific basis for understanding nutrient acquisition and soil N cycle in subtropical plantations. Method: Two-year-old seedlings of common subtropical tree species, including Pinus elliottii, Pinus massoniana, Michelia maudiae, and Liquidambar formosana, were cultured in sands with addition of three different ammonium to nitrate ratios (15∶1, 8∶8, and 1∶15). The inorganic N uptake rates of plants were measured by using the ¹⁵N isotope tracer technique, and the correlations between the inorganic N uptake rates and the morphological and architectural traits of absorptive roots were analyzed. Result: 1) The inorganic N uptake rates of the seedlings of the four species varied under environments with different ammonium to nitrate ratios. The four species preferred to absorb NH₄⁺-N when ammonium was dominant in the sand culture, but preferred to absorb NO₃^?-N when nitrate was dominant. However, species showed different N uptake when the ratio of ammonium to nitrate was 8∶8. The coniferous species absorbed NO₃^?-N at a rate more than twice that of NH₄⁺-N, but there was no significant difference in the uptake of the two forms of nitrogen by broadleaved species. 2) Ammonium-nitrate ratio had a significant impact on root specific length and specific surface area, but had no effect on diameter, tissue density, branching ratio and branching intensity. 3) The inorganic N uptake rate of the four species seedlings was significantly positively correlated with root branches, and significantly negatively correlated with organ biomass. Conclusion: The N uptake rate of seedlings of four tree species depends on substrate N availability and species specificity in response to contrasting edaphic environment. The two coniferous species obtain nutrients through the trade off between physiology (decreased N uptake rate) and morphology (increased specific root length and decreased diameter). However, the two broadleaved species obtain nutrients by simultaneously strengthening the morphological (increased specific root length and surface area), architectural (increased branching ratio), and physiological (increased NH₄⁺-N uptake rate) traits of absorptive roots. These various nutrient acquisition strategies enable tree species to better adapt to changing environments.

Objective: This study aims to investigate the growth and physiological responses of Fraxinus mandshurica inoculated with arbuscular mycorrhizal fungi （AMF） to drought environment, so as to provide theoretical basis for the application of AMF in drought environment, and technical support for the seedling cultivation and production of F. mandshurica in drought environment. Method: F. mandshurica seedlings were used as test plants, and inoculated with AMF of Glomusetunicatum and Glomus mosseae.Three methods of inoculation were set up, namely, single inoculation of G. etunicatum (Ge), single inoculation of G. mosseae (Gm) and mixed inoculation (Mix: Ge+Gm). The non-inoculated seedlings served as the control group (CK). In the greenhouse, potted plants were subjected to different water regimes to simulate natural drought, including light drought (LD) (water control for 5 days), moderate drought (MD) (water control for 10 days) and severe drought (SD) (water control for 15 days), which were compared with normal water (NW) supply in the whole process, to study the response of F. mandshurica seedlings inoculated with AMF in mycorrhizal infection rate, growth, osmotic regulation and antioxidant system under different water conditions. Result: 1）Under drought stress, inoculation was able to promote seedling growth and improve seedling quality. Mixed inoculation was more helpful to improving seedling growth than single inoculation. Mix treatment had a higher mycorrhizal infection rate. Correlation analysis showed that mycorrhizal infection rate was significantly positively correlated with seedling height increment, ground diameter increment, biomass increment, root length, root surface area, average root diameter, soluble protein（Sp）and proline content（Pro）, peroxidase（POD）and superoxide dismutase（SOD）activity (P<0.05), and significantly negatively correlated with malondialdehyde（MDA）content (P<0.05). 2）Under light drought, the increase of seedling height in Mix treatment was 230.30% of CK; Sp content of Mix treatment was 1.1, 1.3 and 1.5 times of that of Ge, Gm and CK, respectively, and Pro content was 25.12%, 34.03% and 68.30% higher than that of Ge, Gm and CK, respectively. Under drought stress, the MDA content in inoculated seedlings was significantly lower than that in non-inoculated seedling（P<0.05）. The activities of POD , SOD and catalase（CAT）were significantly higher than those of non-inoculated seedlings（P<0.05）. Conclusion: Under drought stress, inoculation promotes the growth of seedlings, enhances the osmotic regulation and antioxidant system regulation of seedlings. Compared with single inoculation, mixed inoculation seedlings have stronger drought resistance.

Objective: In this study, the chemical constituents of Cajanus cajan seeds and pods were separated and identified, as well as their antioxidant and anti-inflammatory activities were investigated, in order to provide a scientific basis for the discovery of new natural antioxidant and anti-inflammatory active constituents and the development and utilization of C. cajan resources. Method: The seeds and pods of C. cajan were extracted by 95% ethanol reflux, respectively, and the extracts were filtered and concentrated by reduced pressure to obtain the seed and pod residues. The residues were extracted with different organic solvents, and the ethyl acetate extraction section was further separated and purified by column chromatography techniques such as silica gel and gel. The structures of the isolated compounds were identified using MS and NMR techniques. The antioxidant activities of the isolated compounds were evaluated by measuring the scavenging capacities of DPPH free radicals. The anti-inflammatory activities of the isolated compounds were evaluated by Griess method for determining the inhibitory abilities of the compounds on the NO production in mouse macrophage RAW 264.7 induced by LPS. Result: Four compounds were isolated from the ethyl acetate extraction of C. cajan seeds and identified by ESI-MS and NMR techniques as hydroquinone (S1), 1-linoleoyl-3-palmitoyl glycerol (S2), daucosterol linoleate (S3) and stigmastane-3β,6α-diol (S4). Five compounds were isolated from the ethyl acetate extraction of C. cajan pods and preliminarily identified as flavonoids based on their physicochemical properties, and further identified by ESI-MS and NMR techniques as 2',5,7-trihydroxy-4'-methoxyisoflavone (P1), calycosin (P2), daidzein (P3), 2'-hydroxygenistein (P4) and genistein (P5). Compounds S1–S4, P1–P2 were isolated from the genus Cajanus for the first time, while compound S2 was a new compound. Antioxidant and anti-inflammatory activities studies showed that compounds S1, P1, P2, P4 had relatively strong DPPH free radical scavenging activities, with the EC₅₀ values of 63.10 ± 0.15, 64.97 ± 0.67, 79.63 ± 1.14 and 79.43 ± 1.29 μmol·L^?1, respectively, while compounds S1–S2, P1–P5 showed strong NO inhibitory activities, with the IC₅₀ values of 31.36±0.44, 52.08±1.11, 30.66±0.83, 46.30±0.90, 55.18±2.07, 44.11±0.79 and 44.92±2.24 μmol·L^?1, respectively. The antioxidant and anti-inflammatory activities of compound P1 and the anti-inflammatory activity of compound P4 were reported for the first time. Conclusion: C. cajan seeds mainly contain fatty acid and sterol derivatives, with relatively weak antioxidant and anti-inflammatory activities, while C. cajan pods contain multiple isoflavones with better antioxidant and anti-inflammatory activities. Therefore, C. cajan pods are more valuable for development and utilization, and can be used as a source of raw materials for extracting natural antioxidant and anti-inflammatory components.

Objective: Research on fruit development and seed oil accumulation of Kadsura coccinea can provide a theoretical basis for the cultivation and management of fruit development and the development and utilization of seed oil. Method: In this study, the phenotype, transverse diameter and shape index of fruits and seeds were observed at 8 different stages of fruit development of K. coccinea. The Soxhlet extraction, laser confocal microscopy and gas chromatography methods were used to observe and determine the oil content, oil body shape and distribution as well as fatty acid composition of the seeds. Result: The fruit development period of K. coccinea was about 110 days, which was able to be divided into three stages: green fruit stage (14?56 DAF, days after flowing), color turning stage (56?84 DAF), and red fruit stage (84?112 DAF). The growth curves of horizontal diameter, vertical diameter and mass of fruits and seeds showed a single "S" shape, which was in line with the Logistic regression model, with the determination coefficient as high as 0.967 2?0.998 6. From 14 to 98 DAF was the fruit growth period, and the horizontal diameter, vertical diameter and mass increased rapidly. At maturity, the horizontal diameter of fruit was 115.99 mm, the vertical diameter of fruit was 105.65 mm, and the mass of single fruit was 526.08 g. From 14 to 84 DAF was the seed growth period. At maturity, the horizontal diameter of seed was 12.38 mm, the vertical diameter of seed was 14.26 mm, and the mass of 100-seed was 47.85 g. The oil accumulation rule of seeds was "slow-fast-slow". The accumulation was slow at green fruit stage, rapid accumulation at color change stage, and slow accumulation at red fruit stage. The oil accumulation equation wasy = 56.261 2 · (1+ $ {\mathrm{e}}^{6.582\mathrm{ }\mathrm{ }\mathrm{ }\mathrm{ }\mathrm{ }\mathrm{ }1-0.102t} $ ) ^?1. The seed oil body ofK. coccinea was spherical, and the volume became larger and the number increased, and gradually filled the whole cell with the development of seeds. A total of 16 fatty acids were detected during oil accumulation, mainly palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid, with the highest content of linoleic acid. The oil content of mature seeds of K. coccinea was up to 55.51 g·100 g^?1, in which unsaturated fatty acids accounted for 77.10%, and the relative content of linoleic acid was 66.88%, belonging to high quality vegetable oils. Conclusion: The patterns of fruit development and seed oil accumulation of K. coccinea conform to the Logistic regression model. The Logistic equation can reflect the situation of fruit development and oil accumulation, which has important guiding significance for fruit production. K. coccinea seed has high oil content, regular oil shape and high oil quality, so that it has great potential and development value as plant edible oil.

Objective: The aril cracking of Torreya grandis cv. ‘Merrilii’ (T. grandis) is an important process for obtaining its seeds. The cracking period of T. grandis aril is long, which leads to high harvesting cost. This study aims to study the changes of cell wall metabolism and structure of T. grandis aril during the different growth stages, and provide theoretical basis for further exploring the mechanism of aril cracking and exploring measures to promote aril cracking. Method: During the different development stages of seeds, the changes of the cracking rate and firmness of T. grandis aril were measured, and the changes in cell wall components and its related degradation enzyme activity were also analyzed. Combined with anatomic structure observation of aril at different growth stages, the role of cell wall metabolism and structural changes in the cracking process was investigated. The ethylene production rate of T. grandis seeds was measured during growth stages, and the role of ethylene in the cracking process of aril was explored by using the inhibitor of ethephon/ethylene (1-methylcyclopropylene, 1-MCP), and the relationship between ethylene and the cracking of the aril was analyzed. Result: 1) From 134?154 days after the seeds protrusion (DASP), the cracking rate of aril inT. grandis significantly increased by 10 times, the firmness significantly decreased by 61%, and thickness of aril increased by 43%. When arils were cracking (154 DASP), there were obvious separation layers between the resin canal near the inner epidermis and its nearby resin canal, as well as between the middle parenchyma cell layer and the inner epidermis. 2) From 134?154 DASP, the water-soluble pectin (WSP) in aril significantly increased, while the CDTA soluble pectin (SSP) and Na₂CO₃ soluble pectin (CSP) significantly decreased, and the activities of related degradation enzymes, such as pectin methyl esterase (PME) and polygalacturonase (PG) showed a significant increasing trend. In addition, PME and PG activities were negatively correlated with its firmness. 3) From 134?154 DASP, the ethylene production rate ofT. grandis seeds showed an increased at first and then decreased trend, and the spraying of ethephon solution was able to significantly increase the cracking rate of T. grandis aril, and decrease firmness. There was significantly positive correlation between ethylene production rate and cracking rate, or negative correlation between ethylene production rate and firmness. Conclusion: T. grandis aril starts to gradually go into cracking stage since 134 DASP, and the cracking of T. grandis aril is affected by the inner epidermis layer and the parenchyma cell layer. Besides, the cracking of aril is closely related to the metabolism of pectin and ethylene production.

Objective: This study aims to understand the reproductive and developmental anatomical characteristics of Taxodium mucronatum × T. distichum. Method: In this study, the changes in morphology and anatomy structure of ovulate strobilus of T. mucronatum were systematically observed throughout its whole developmental process from flower bud initiation to seed maturation. Result: The results showed that the period of megasporogenesis and development of female gametophytes was from January to May. The meiotic division of the megasporocyte produced four megaspores, among which the megaspore near the chalaza developed into a functional megaspore, while the other three megaspores near the micropyle degenerated. The archegonia complex was composed of 13 to 19 archegonia covered by a layer of jacket cells with two nucleuses, and positioned terminally without ventral canal nucleus. Fertilization took place in the middle of June. With the growth of the pollen tube, the spermatogenous cell enlarged continuously and before fertilization, it divided into two homotypic sperms, and one of the sperms fertilized the egg to form a zygote. The fusion of sperm and egg occurred mainly in the center and upper of the archegonium. The proembryony development was from late June to early July, early embryo development was from mid-July to early August, and mature embryo development was from mid-August to mid-September. The proembryony of T. mucronatum belongs to the standard type of coniferales. Simple polyembryony and cleaved polyembryony were found frequently, and the development of the embryo was not synchronous. The mature embryo is linear, with 4~9 cotyledons, and no pith in the embryonal axis. Conclusion: This study for the first time has observed the cytological process of megasporogenesis, female gametophyte development of T. mucronatum, reproductive fusion and embryo development of T. mucronatum × T. distichum, which would provide a reproductive biological basis for interspecific hybridization breeding of T. mucronatum × T. distichum.

This paper describes a new species of the genus Nematus (Hymenoptera: Tenthredinidae), Nematus maculostigmatus Liu & Wei, sp. nov. The insect is collected from Pinggu District, Beijing, where its larvae feed on leaves of Quercus variabilis and even can defoliate entire tree leaves at high densities. Recurrent defoliation can cause major dieback. The new species is similar to N. princeps Zaddach, 1876, but can be distinguished from the latter by the following characters: labrum, tegula, large stripe on dorsal side of fore and middle femora, spot of hind femur, except apical 1/5 on dorsal side of fore and middle tibiae, basal 2/3 of hind tibia, whole tergum 1, and most parts of tergum 2 yellow; malar space 0.5 times as long as diameter of median ocellus; ovipositor sheath 1.3 times as long as front tibia; each middle serrula of lancet with 4–6 distal teeth; annular suture 1 oblique to apex, 2^nd–15^th sutures with setae bands, longest setae band about 3/5 length of annulus; radix 0.7 times as long as lamnium; valvispina of penis valve obliqued distinctly. N. princeps Zaddach, 1876 is recognized as follow: labrum and part of tegula dark brown; femora and tibiae of fore and middle legs, except apical margins of each tarsomere of fore and middle tarsi, basal 1/3 of hind femur reddish yellow; most parts of terga 3–4 yellow; malar space 1.5 times as long as diameter of median ocellus; ovipositor sheath 0.8 times as long as front tibia; each middle serrula of lancet with 9–12 distal teeth; annular suture 1 not obliqued; 2^nd–13^th sutures with setae bands, longest setae band about 1/3 length of annulus; radix 0.9 times as long as lamnium; valvispina of penis valve not obliqued, ventral side of apex with a protrusion. The genomic DNA of the new species was extracted by using the DNeasy Tissue Kit (Qiagen, Valencia, CA), sequence of the mitochondrial gene Cytochrome oxidase Ⅰ (COⅠ) were obtained from sequencing, with 810 bp in length; another 14 COⅠ sequences of known Nematus and Pristiphora species used in previous phylogenetic analyses were downloaded from GenBank, and formed the CO I sequence data set with the new species sequence. The results of Kimura 2-parameter model distance of the 12 Nematus COⅠ sequences showed that the K2P distance between N. maculostigmatus and N. princeps was the smallest, 0.116. Phylogenetic tree of Nematus and related genus species based on Bayesian phylogenetic analysis of COⅠ sequences was constructed, and the results showed that all the Nematus species formed a monophyletic group, including the new species. The holotype and all paratypes of the new species were deposited in the Asian Sawfly Museum, Nanchang, China (ASMN).

Objective: This study aims to explore the cause of heat tolerance formation in Agrilus planipennis (emerald ash borer, EAB) adults from the physiological level, so as to provide guidance for revealing the formation mechanism of insect resistance to environmental stress. Method: EAB male and female adults were incubated in different high temperature (30, 33, 37 and 41 ℃) and 25 ℃ (served as the control) conditions for 4, 8 and 12 h, respectively, and the insects were collected to measure the water content, fat content, and glycogen, glucose, trehalose, and protein content. Result: With the increase of temperature and the extension of the duration of high temperature, the contents of water and fat in both male and female adults of EAB showed a downward trend. With temperature increasing, the glycogen content was increased, while the contents of glucose and trehalose increased first and then decreased, reaching the highest level at 33?37 ℃. The contents of glycogen, glucose and trehalose in the male and female adults all generally showed an upward trend with increasing time under high temperature. The protein content in the male and female adults increased with fluctuation with the increase of temperature, but gradually decreased with the extension of high temperature duration. The contents of water, fat and glycogen in EAB male adults were significantly higher than those in the female adults, while the contents of trehalose and protein were relatively lower than those in female adults. Conclusion: Under short-time high-temperature conditions, the fat content, and various sugars and protein contents of EAB adults have changed obviously to some extent. The water and fat contents are less affected by temperature and the treatment duration, while the sugar and protein contents are significantly influenced by temperature and the treatment duration. Many stress-resistant substances, such as sugar and protein, play an important role in regulating the resistance of EAB adults against high temperature conditions.

Objective: There are many forest pest species, and some of them are morphologically similar with small visual differences, and are difficult to be distinguished, which makes it difficult for forestry prevention and control technicians to quickly and accurately identify them. In regard to those problems, this paper proposes a fine-grained image identification method of forest pests based on deep bilinear transformation attention mechanism network (DBTANet). Method: The images of 60 forest pests and 14 harmful forest plants were targeted. The original images were enhanced by methods including horizontal mirror, brightness adjustment, Gaussian blur and Gaussian noise. All images were divided into training dataset, verification dataset and test dataset by a 6∶2∶2 ratio. The bilinear interpolation method was used to scale each image to a uniform size. The residual module in the ResNet network was improved. A deep bilinear conversion module and an attention mechanism module were added. DBTANet-101 model was developed to extract features and classify forest pest species. Three evaluation indexes of average accuracy, average recall rate and average F₁ score were used to evaluate the identification results of forestry pests by thd different models. Result: A total of 74 forest pest species were identified by five models of VGGNet-19, ResNet-50, ResNet-101, improved ResNet-50 and improved ResNet-101, respectively, and the average accuracy rates of the five models were 78.6%, 74.9%, 76.3%, 79.7% and 81.1%, respectively. On the basis of improved ResNet-101 of the residual module, the deep bilinear conversion module and the attention mechanism module were added, after then the average recognition rate and recall rate of 74 forestry pests increased by 10.2% and 12.1%, respectively. The average recognition rate of fine-grained images of 22 similar pests increased by 15.7%. Conclusion: The fine-grained image recognition method of forest pests based on deep bilinear transformation attention mechanism network (DBTANet) achieves the average identification rate of 74 forest pests by 91.3% and the average identification rate of 22 similar forest pest species by 85.1%. The bilinear transformation module and the attention mechanism can effectively improve the accuracy of the forest pest identification model.