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Old Pinus massoniana forests benefit more from recent rapid warming in humid subtropical areas of central-southern China
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作者 Wenxin Li Liangjun Zhu +4 位作者 Lianhua Zhu Mengdan Jing Censhi Qian Yu Zhu Paolo Cherubini 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期155-170,共16页
Trees progress through various growth stages,each marked by specific responses and adaptation strate-gies to environmental conditions.Despite the importance of age-related growth responses on overall forest health and... Trees progress through various growth stages,each marked by specific responses and adaptation strate-gies to environmental conditions.Despite the importance of age-related growth responses on overall forest health and management policies,limited knowledge exists regarding age-related effects on dendroclimatic relationships in key subtropical tree species.In this study,we employed a den-drochronological method to examine the impact of rapid warming on growth dynamics and climatic sensitivity of young(40–60 years)and old(100–180 years)Pinus mas-soniana forests across six sites in central-southern China.The normalized log basal area increment of trees in both age groups increased significantly following rapid warming in 1984.Trees in young forests further showed a distinct growth decline during a prolonged severe drought(2004–2013),whereas those in old forests maintained growth increases.Tree growth was more strongly influenced by temperature than by moisture,particularly in old forests.Spring tem-peratures strongly and positively impacted the growth of old trees but had a weaker effect on young ones.Old forests had a significantly lower resistance to extreme drought but faster recovery compared to young forests.The“divergence problem”was more pronounced in younger forests due to their heightened sensitivity to warming-induced drought and heat stress.With ongoing warming,young forests also may initially experience a growth decline due to their heightened sensitivity to winter drought.Our findings underscore the importance of considering age-dependent changes in forest/tree growth response to warming in subtropical forest man-agement,particularly in the context of achieving“Carbon Peak&Carbon Neutrality”goals in China. 展开更多
关键词 Tree rings Pinus massoniana Age effects Drought resilience Subtropical forests Rapid warming
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Achievements and challenges of primate conservation in China 被引量:1
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作者 Bao-Guo Li He Zhang +21 位作者 Ming Li Xue-Long Jiang Peng-Fei Fan Jiang Zhou Song-Tao Guo Xiao-Guang Qi Jin-Hua Li Ji-Qi Lu Dong-Po Xia Liang-Wei Cui Zuo-Fu Xiang Qi-Hai Zhou Zhi-Pang Huang Cheng-Ming Huang Wen Xiao Hui-Jian Hu Zhi-Xin Zhou Ming-Yong Chen Da-Yong Li Peng-Lai Fan Yin Yang Ru-Liang Pan 《Zoological Research(Diversity and Conservation)》 2024年第1期66-74,共9页
The dual impact of climate change and human activities has precipitated a sharp decline in primate biodiversity globally.China is home to the most diverse primate species in the Northern hemisphere,which face severe e... The dual impact of climate change and human activities has precipitated a sharp decline in primate biodiversity globally.China is home to the most diverse primate species in the Northern hemisphere,which face severe ecological threats due to the expansion of modern agriculture,extensive exploitation and consumption of natural resources,and excessive land development during its transition from an agricultural to a modern society.In response,China has implemented various ecological conservation measures,including habitat restoration and protection.These efforts have made substantial strides in biodiversity conservation,with certain regions witnessing an increase in primate populations.In the current study,we conducted a systematic review of historical documents and field research data related to Chinese primates,evaluating the endangered status of primate species in China.Despite improvements in the habitats of most primate species and some population growth,many species still face severe threats,including declining and small populations.Species such as the Myanmar snub-nosed monkey(Rhinopithecus strykeri),eastern black crested gibbon(Nomascus nasutus),and Hainan gibbon(N.hainanus)remain particularly vulnerable due to their limited distribution ranges and extremely small populations.Insufficient scientific data,fragmented information,and not enough studies in conservation biology further compound the challenges.Moreover,there is a notable lack of detailed population monitoring data for species such as the Bengal slow loris(Nycticebus bengalensis),pygmy slow loris(N.pygmaeus),Indochinese gray langur(Trachypithecus crepusculus),Shortridge’s langur(T.shortridgei),and capped langur(T.pileatus),which hinders the development of practical and targeted conservation management strategies.Therefore,for national biodiversity conservation,there is an urgent need for specialized primate surveys,enhancing habitat protection and restoration,and increasing focus on cross-border conservation strategies and regional cooperation.There is also a need to establish a comprehensive and systematic research database platform,conduct continuous and in-depth research in primate biology,and actively engage in the scientific assessment of ecotourism.Additionally,strengthening public awareness and education on wildlife conservation remains essential.Such integrated and systematic efforts will provide scientific support for the current and future conservation and management of primate species in China. 展开更多
关键词 PRIMATES BIODIVERSITY Habitat fragmentation Habitat restoration Conservation strategies
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Aboveground carbon sequestration of Cunninghamia lanceolata forests:Magnitude and drivers
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作者 Chen Wang Shuguang Liu +3 位作者 Yu Zhu Andrew R.Smith Ying Ning Deming Deng 《Forest Ecosystems》 SCIE CSCD 2024年第1期32-41,共10页
Understanding the spatial variation,temporal changes,and their underlying driving forces of carbon sequestration in various forests is of great importance for understanding the carbon cycle and carbon management optio... Understanding the spatial variation,temporal changes,and their underlying driving forces of carbon sequestration in various forests is of great importance for understanding the carbon cycle and carbon management options.How carbon density and sequestration in various Cunninghamia lanceolata forests,extensively cultivated for timber production in subtropical China,vary with biodiversity,forest structure,environment,and cultural factors remain poorly explored,presenting a critical knowledge gap for realizing carbon sequestration supply potential through management.Based on a large-scale database of 449 permanent forest inventory plots,we quantified the spatial-temporal heterogeneity of aboveground carbon densities and carbon accumulation rates in Cunninghamia lanceolate forests in Hunan Province,China,and attributed the contributions of stand structure,environmental,and management factors to the heterogeneity using quantile age-sequence analysis,partial least squares path modeling(PLS-PM),and hot-spot analysis.The results showed lower values of carbon density and sequestration on average,in comparison with other forests in the same climate zone(i.e.,subtropics),with pronounced spatial and temporal variability.Specifically,quantile regression analysis using carbon accumulation rates along an age sequence showed large differences in carbon sequestration rates among underperformed and outperformed forests(0.50 and 1.80 Mg·ha^(-1)·yr^(-1)).PLS-PM demonstrated that maximum DBH and stand density were the main crucial drivers of aboveground carbon density from young to mature forests.Furthermore,species diversity and geotopographic factors were the significant factors causing the large discrepancy in aboveground carbon density change between low-and high-carbon-bearing forests.Hotspot analysis revealed the importance of culture attributes in shaping the geospatial patterns of carbon sequestration.Our work highlighted that retaining largesized DBH trees and increasing shade-tolerant tree species were important to enhance carbon sequestration in C.lanceolate forests. 展开更多
关键词 Carbon density Carbon accumulation rate Forest age Spatial variation Cultural influence
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Identification of banana leaf disease based on KVA and GR-ARNet
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作者 Jinsheng Deng Weiqi Huang +3 位作者 Guoxiong Zhou Yahui Hu Liujun Li Yanfeng Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3554-3575,共22页
Banana is a significant crop,and three banana leaf diseases,including Sigatoka,Cordana and Pestalotiopsis,have the potential to have a serious impact on banana production.Existing studies are insufficient to provide a... Banana is a significant crop,and three banana leaf diseases,including Sigatoka,Cordana and Pestalotiopsis,have the potential to have a serious impact on banana production.Existing studies are insufficient to provide a reliable method for accurately identifying banana leaf diseases.Therefore,this paper proposes a novel method to identify banana leaf diseases.First,a new algorithm called K-scale VisuShrink algorithm(KVA)is proposed to denoise banana leaf images.The proposed algorithm introduces a new decomposition scale K based on the semi-soft and middle course thresholds,the ideal threshold solution is obtained and substituted with the newly established threshold function to obtain a less noisy banana leaf image.Then,this paper proposes a novel network for image identification called Ghost ResNeSt-Attention RReLU-Swish Net(GR-ARNet)based on Resnet50.In this,the Ghost Module is implemented to improve the network's effectiveness in extracting deep feature information on banana leaf diseases and the identification speed;the ResNeSt Module adjusts the weight of each channel,increasing the ability of banana disease feature extraction and effectively reducing the error rate of similar disease identification;the model's computational speed is increased using the hybrid activation function of RReLU and Swish.Our model achieves an average accuracy of 96.98%and a precision of 89.31%applied to 13,021 images,demonstrating that the proposed method can effectively identify banana leaf diseases. 展开更多
关键词 banana leaf diseases image denoising Ghost Module Res Ne St Module Convolutional Neural Networks GR-ARNet
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Improving Semi-Dried Brown Rice Noodle Quality via Mixed Fermentation of Lactobacillus and Yeast
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作者 LUO Lijuan CHENG Zixuan +6 位作者 QIAO Fan XIONG Gangping LIU Jun HUANG Qingming LI Jiangtao LIN Qinlu LIU Chun 《Rice science》 SCIE CSCD 2024年第5期489-493,I0001-I0005,共10页
To address the coarse texture and poor cooking quality of brown rice flour,we employed fermentation using lactobacillus and yeast in varying proportions.The fermented flour from early indica rice Pear 13 was then proc... To address the coarse texture and poor cooking quality of brown rice flour,we employed fermentation using lactobacillus and yeast in varying proportions.The fermented flour from early indica rice Pear 13 was then processed into semi-dried brown rice noodles. 展开更多
关键词 DRIED COOKING YEAST
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KnowledgeMapping of Hybrid Solar PV andWind Energy Standalone Systems: A Bibliometric Analysis
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作者 Quan Zhou Haiyang Li 《Energy Engineering》 EI 2024年第7期1781-1803,共23页
Renewable energy is becoming more attractive as traditional fossil fuels are rapidly depleted and expensive,and their use would release pollutants.Power systems that use both wind and solar energy are more reliable an... Renewable energy is becoming more attractive as traditional fossil fuels are rapidly depleted and expensive,and their use would release pollutants.Power systems that use both wind and solar energy are more reliable and efficient than those that utilize only one energy.Hybrid renewable energy systems(HRES)are viable for remote areas operating in standalone mode.This paper aims to present the state-of-the-art research on off-grid solar-wind hybrid energy systems over the last two decades.More than 1500 published articles extracted from the Web of Science are analyzed by bibliometric methods and processed by CiteSpace to present the results with figures and tables.Productive countries and highly cited authors are identified,and hot topics with hotspot articles are shown in landscape and timeline views.Emerging trends and new developments related to techno-economic analysis and microgrids,as well as the application of HOMER software,are predicted based on the analysis of citation bursts.Furthermore,the opportunities of hybrid energy systems for sustainable development are discussed,and challenges and possible solutions are proposed.The study of this paper provides researchers with a comprehensive understanding and intuitive representation of standalone solar-wind hybrid energy systems. 展开更多
关键词 Wind energy solar PV standalone citation bursts emerging trends
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Development Status and Countermeasures of Farmers' Professional Cooperatives in Shangqiu City
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作者 Xiaofan XIAO 《Agricultural Biotechnology》 2024年第3期41-44,共4页
Farmers' professional cooperatives develop in various forms,and with the continuous improvement of development level,social effects have gradually appear.Based on the specific situation of farmers' professiona... Farmers' professional cooperatives develop in various forms,and with the continuous improvement of development level,social effects have gradually appear.Based on the specific situation of farmers' professional cooperatives in Shangqiu City,this paper expounded the development status of farmers' professional cooperatives in Shangqiu City,analyzed and discussed various problems encountered in the development process of farmers' professional cooperatives,and put forward some countermeasures and suggestions,such as establishing and perfecting cooperative rules and regulations,financing from multiple channels,introducing technical talents in various ways,breaking the information asymmetry restriction by various means,and giving full play to government functions,aiming to further promote standardized,large-scale,healthy and sustainable development of farmers' professional cooperatives. 展开更多
关键词 Farmers'professional cooperatives Shangqiu city Development status Existing problems Countermeasure analysis
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Problems and Countermeasures in the Training of Master of Translation and Interpreting Talents in the Context of Technological Empowerment
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作者 Tangxikun He 《Journal of Contemporary Educational Research》 2024年第8期76-87,共12页
This paper aims to explore the problems and countermeasures in the training of Master of Translation and Interpreting(MTI)talents in the context of technological empowerment.Through methods such as questionnaires and ... This paper aims to explore the problems and countermeasures in the training of Master of Translation and Interpreting(MTI)talents in the context of technological empowerment.Through methods such as questionnaires and literature review,the study analyzes the problems in the training of MTI talents under technological empowerment and,by examining the feasibility and applicability of technologies,proposes countermeasures to these problems.The research finds that there are still problems in four areas:training concept,teaching content,research in the current training of MTI talents,and mutual empowerment of technology and education.Four countermeasures are suggested to address these problems,including utilizing technology to promote personalized training and optimize teaching content.This study provides valuable references for future educators to leverage technology in the training of MTI talents. 展开更多
关键词 PROBLEM COUNTERMEASURE Talent training Master of Translation and Interpreting Technological empowerment
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Inhibition of Propionibacterium acnes by refined bamboo vinegar and preparation of the slow-release system with bamboo charcoal as the carrier
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作者 Ziyi Li Yanan Wang Sheng Zhang 《Journal of dermatologic science and cosmetic technology》 2024年第2期17-25,共9页
Background:Acne vulgaris is one of the most common skin diseases that can significantly impact a considerable proportion of individuals over their lifetime.Objective:This study focuses on the exploration of the applic... Background:Acne vulgaris is one of the most common skin diseases that can significantly impact a considerable proportion of individuals over their lifetime.Objective:This study focuses on the exploration of the application potential of bamboo vinegar in cosmetics.Materials and Methods:The stock solution of bamboo vinegar is subjected to reduced-pressure distillation at different temperatures to obtain refined bamboo vinegar.Then,inhibition of Propionibacterium acnes(P.acnes)by refined bamboo vinegar is observed.Moreover,the refined bamboo vinegar is adsorbed and released with activated bamboo charcoal as the carrier.In all,this study aims to probe into the mechanism of the controlledrelease system of bamboo vinegar.Results:The results shows that the harmful substances(tar)in bamboo vinegar distilled at 70℃decreased by 94.44%,which is a more notable decrease compared with that in the stock solution.The total organic acid content in bamboo vinegar after reduced-pressure distillation is 11.840%,reaching the national standard for refined bamboo vinegar(GB/T 31734–2015).Additionally,the minimum inhibitory concentration of refined bamboo vinegar against P.acnes using the punch method is 7.90 mg/mL.This indicates that refined bamboo vinegar has the potential as a prospective raw material for formulations in anti-acne cosmetic products.Furthermore,the release rate of bamboo charcoal/bamboo vinegar in water for 15 min reaches 70.57%,which then slows down to a plateau.The slow-release behavior is agreed with the Ritger-Peppas model and is beneficial to relieve the irritation of bamboo vinegar to the skin and lengthen its bacteriostatic duration.Conclusion:The foregoing conclusions can serve as the theoretical foundation for the application of bamboo vinegar in anti-acne cosmetics. 展开更多
关键词 Bamboo vinegar REFINEMENT Propionibacterium acne Bamboo charcoal
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Neotype designation and redescription of Tropidophorus guangxiensis Wen, 1992(Squamata:Sauria: Scincidae), with description of a new subspecies from central South China 被引量:2
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作者 Ke-Ji Guo Fu Shu +4 位作者 Nan-Fei Wu Shun-De Chen Mian Hou Sheng-Chao Shi Xue-Jian Deng 《Zoological Research》 SCIE CAS CSCD 2021年第5期606-613,共8页
The genus Tropidophorus consists of small semi-aquatic lizards that dwell in lowland forest steams(Barbour,1921;Bauer&Jackman,2008).Here,we designate the neotype and re-describe T.guangxiensis Wen,1992 based on ne... The genus Tropidophorus consists of small semi-aquatic lizards that dwell in lowland forest steams(Barbour,1921;Bauer&Jackman,2008).Here,we designate the neotype and re-describe T.guangxiensis Wen,1992 based on newly collected topotypic specimens.We also describe a new subspecies from Xuefeng Mountain,Hongjiang County。 展开更多
关键词 forest SUBSPECIES
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Spatial and temporal patterns of the sensitivity of radial growth response by Picea schrenkiana to regional climate change in the Tianshan Mountains 被引量:5
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作者 Zhongtong Peng Yuandong Zhang +6 位作者 Liangjun Zhu Mingming Guo Qingao Lu Kun Xu Hui Shao Qifeng Mo Shirong Liu 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第6期1669-1681,共13页
Climate change significantly impacts forest ecosystems in arid and semi-arid regions.However,spatiotemporal patterns of climate-sensitive changes in individual tree growth under increased climate warming and precipita... Climate change significantly impacts forest ecosystems in arid and semi-arid regions.However,spatiotemporal patterns of climate-sensitive changes in individual tree growth under increased climate warming and precipitation in north-west China is unclear.The dendrochronological method was used to study climate response sensitivity of radial growth of Picea schrenkiana from 158 trees at six sites during 1990-2020.The results show that climate warming and increased precipitation significantly promoted the growth of trees.The response to temperature first increased,then decreased.However,the response to increased precipitation and the self-calibrating Palmer Drought Severity Index(scPDSI)increased significantly.In most areas of the Tianshan Mountains,the proportion of trees under increased precipitation and scPDSI positive response was relatively high.Over time,small-diameter trees were strongly affected by drought stress.It is predicted that under continuous warming and increased precipitation,trees in most areas of the Tianshan Mountains,especially those with small diameters,will be more affected by precipitation. 展开更多
关键词 Regional climate change Picea schrenkiana Climate response sensitivity Spatiotemporal patterns Tianshan mountains
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Spatial-temporal changes and driving factors of eco-environmental quality in the Three-North region of China 被引量:3
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作者 LONG Yi JIANG Fugen +2 位作者 DENG Muli WANG Tianhong SUN Hua 《Journal of Arid Land》 SCIE CSCD 2023年第3期231-252,共22页
Eco-environmental quality is a measure of the suitability of the ecological environment for human survival and socioeconomic development.Understanding the spatial-temporal distribution and variation trend of eco-envir... Eco-environmental quality is a measure of the suitability of the ecological environment for human survival and socioeconomic development.Understanding the spatial-temporal distribution and variation trend of eco-environmental quality is essential for environmental protection and ecological balance.The remote sensing ecological index(RSEI)can quickly and objectively quantify eco-environmental quality and has been extensively utilized in regional ecological environment assessment.In this paper,Moderate Resolution Imaging Spectroradiometer(MODIS)images during the growing period(July-September)from 2000 to 2020 were obtained from the Google Earth Engine(GEE)platform to calculate the RSEI in the three northern regions of China(the Three-North region).The Theil-Sen median trend method combined with the Mann-Kendall test was used to analyze the spatial-temporal variation trend of eco-environmental quality,and the Hurst exponent and the Theil-Sen median trend were superimposed to predict the future evolution trend of eco-environmental quality.In addition,ten variables from two categories of natural and anthropogenic factors were analyzed to determine the drivers of the spatial differentiation of eco-environmental quality by the geographical detector.The results showed that from 2000 to 2020,the RSEI in the Three-North region exhibited obvious regional characteristics:the RSEI values in Northwest China were generally between 0.2 and 0.4;the RSEI values in North China gradually increased from north to south,ranging from 0.2 to 0.8;and the RSEI values in Northeast China were mostly above 0.6.The average RSEI value in the Three-North region increased at an average growth rate of 0.0016/a,showing the spatial distribution characteristics of overall improvement and local degradation in eco-environmental quality,of which the areas with improved,basically stable and degraded eco-environmental quality accounted for 65.39%,26.82%and 7.79%of the total study area,respectively.The Hurst exponent of the RSEI ranged from 0.20 to 0.76 and the future trend of eco-environmental quality was generally consistent with the trend over the past 21 years.However,the areas exhibiting an improvement trend in eco-environmental quality mainly had weak persistence,and there was a possibility of degradation in eco-environmental quality without strengthening ecological protection.Average relative humidity,accumulated precipitation and land use type were the dominant factors driving the spatial distribution of eco-environmental quality in the Three-North region,and two-factor interaction also had a greater influence on eco-environmental quality than single factors.The explanatory power of meteorological factors on the spatial distribution of eco-environmental quality was stronger than that of topographic factors.The effect of anthropogenic factors(such as population density and land use type)on eco-environmental quality gradually increased over time.This study can serve as a reference to protect the ecological environment in arid and semi-arid regions. 展开更多
关键词 eco-environmental quality remote sensing ecological index Google Earth Engine Hurst exponent geographical detector Three-North region of China
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Selecting the Technology of Sodium Silicate Modified Poplar with the Highest Performance by Fuzzy Orthogonal Method 被引量:1
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作者 Xiaoqian Bi Pengfei Guan +3 位作者 Ping Li Yuan Zhang Xingong Li Yingfeng Zuo 《Journal of Renewable Materials》 SCIE EI 2023年第5期2399-2415,共17页
Sodium silicate modification can improve the overall performance of wood.The modification process has a great influence on the properties of modified wood.In this study,a new method was introduced to analyze the wood ... Sodium silicate modification can improve the overall performance of wood.The modification process has a great influence on the properties of modified wood.In this study,a new method was introduced to analyze the wood modification process,and the properties of modified wood were studied.Poplar wood was modified with sodium silicate by vacuum-pressure impregnation.After screening using single-factor experiments,an orthogonal experiment was carried out with solution concentration,impregnation time,impregnation pressure,and the cycle times as experimental factors.The modified poplar with the best properties was selected by fuzzy mathematics and characterized by SEM,FT-IR,XRD and TG.The results showed that some lignin and hemicellulose were removed from the wood due to the alkaline action of sodium silicate,and the orderly crystal area of poplar became disorderly,resulting in the reduction of crystallinity of the modified poplar wood.FT-IR analysis showed that sodium silicate was hydrolyzed to form polysilicic acid in wood,and structural analysis revealed the formation of Si-O-Si and Si-O-C,indicating that sodium silicate reacted with fibers on the wood cell wall.TG-DTG curves showed that the final residual mass of modified poplar wood increased from 25%to 67%,and the temperature of the maximum loss rate decreased from 343℃ to 276℃.The heat release and smoke release of modified poplar wood decreased obviously.This kind of material with high strength and fire resistance can be used in the outdoor building and indoor furniture. 展开更多
关键词 Poplar wood sodium silicate impregnation modification fuzzy orthogonal method process optimization flame retardant
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Integration of semi-in vivo assays and multi-omics data reveals the effect of galloylated catechins on self-pollen tube inhibition in Camellia oleifera 被引量:1
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作者 Yihong Chang Wenfang Gong +4 位作者 Jinming Xu Han Gong Qiling Song Shixin Xiao Deyi Yuan 《Horticulture Research》 SCIE CSCD 2023年第1期260-273,共14页
Camellia oil extracted from the seeds of Camellia oleifera Abel.is a popular and high-quality edible oil,but its yield is limited by seed setting,which is mainly caused by self-incompatibility(SI).One of the obvious b... Camellia oil extracted from the seeds of Camellia oleifera Abel.is a popular and high-quality edible oil,but its yield is limited by seed setting,which is mainly caused by self-incompatibility(SI).One of the obvious biological features of SI plants is the inhibition of self-pollen tubes;however,the underlying mechanism of this inhibition in C.oleifera is poorly understood.In this study,we constructed a semi-in vivo pollen tube growth test(SIV-PGT)system that can screen for substances that inhibit self-pollen tubes without interference from the genetic background.Combined with multi-omics analysis,the results revealed the important role of galloylated catechins in self-pollen tube inhibition,and a possible molecular regulatory network mediated by UDP-glycosyltransferase(UGT)and serine carboxypeptidase-like(SCPL)was proposed.In summary,galloylation of catechins and high levels of galloylated catechins are specifically involved in pollen tube inhibition under self-pollination rather than cross-pollination,which provides a new understanding of SI in C.oleifera.These results will contribute to sexual reproduction research on C.oleifera and provide theoretical support for improving Camellia oil yield in production. 展开更多
关键词 VIVO oleifera INTEGRATION
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Optical and Mechanical Properties of Ramie Fiber/Epoxy Resin Transparent Composites
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作者 Chunhua Liu Dongfang Zou +3 位作者 Qinqin Huang Shang Li Xia Zheng Xingong Li 《Journal of Renewable Materials》 EI 2023年第10期3613-3624,共12页
The residual resources of ramie fiber-based textile products were used as raw materials.Ramie fiber felt(RF)was modified by NaClO_(2) aqueous solution and then impregnated with water-based epoxy resin(WER).RF/WER tran... The residual resources of ramie fiber-based textile products were used as raw materials.Ramie fiber felt(RF)was modified by NaClO_(2) aqueous solution and then impregnated with water-based epoxy resin(WER).RF/WER transparent composite materials were prepared by lamination hot pressing process.The composite materials’color difference,transmittance,haze,density,water absorption,and mechanical properties were determined to assess the effects of NaClO_(2) treatment and the number of ramie fiber layers on the properties of the prepared composites.The results showed significantly improved optical and mechanical properties of the RF/WER transparent composites after NaClO_(2) treatment.With the increase of ramie fiber layers,the composites’whiteness,transmittance,and water absorption decreased while the haze increased.For material with three layers,the optical transmittance in the visible light region was 82%,and the haze was 96%,indicating the material has both high transmittance and high haze characteristics.The tensile strength increases with the increase of the number of layers,and the tensile strength of the composite with six layers is 243 MPa.This study broadens the scope of application of ramie fiber as a new option for home decoration materials. 展开更多
关键词 Ramie fiber water-based epoxy transparent composites TRANSMITTANCE HAZE tensile strength
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Distribution and conservation of near threatened plants in China
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作者 Qin Liu Tian-Tian Xue +6 位作者 Xiao-Xia Zhang Xu-Dong Yang Fei Qin Wen-Di Zhang Lei Wu Rainer W.Bussmann Sheng-Xiang Yu 《Plant Diversity》 SCIE CAS CSCD 2023年第3期272-283,共12页
Plants classified as Near Threatened(NT) are at high risk of becoming threatened because of anthropogenic interference and climate change.Especially in conservation efforts,such species have however long been overlook... Plants classified as Near Threatened(NT) are at high risk of becoming threatened because of anthropogenic interference and climate change.Especially in conservation efforts,such species have however long been overlooked.Here,we obtained 98,419 precise occurrence points for 2442 NT plants in China,and used species richness,species complementarity,and weighted endemism that consider all,endemic and narrow-ranged species in order to identify the diversity hotspots of NT plants.Then we evaluated the conservation effectiveness of current nature reserves for them.Our results indicate that the diversity hotspots of NT plants were mainly confined to southwestern and southern China,and only 35.87% of hotspots and 71.5% of species were protected by nature reserves.Numerous hotspots in southwestern China(e.g.,Sichuan,Yunnan,Guangxi,and Hainan) were identified as conservation gaps.Given that NT plants include large proportions of endemic and narrow-ranged species,they represent an important value in conservation priority.So,more conservation efforts in the future should be tilted towards NT plants.Additionally,when comparing with the recently updated NT list,there are already 87 species raised to threatened categories,while 328 species were lowered to least concern,56 species were now categorized as data deficient,and 119 species considered as uncertain due to changes of scientific names.It is essential to carry out a continuous assessment of species’ threatened categories to realize targeting conservation. 展开更多
关键词 CONSERVATION Distribution patterns Diversity hotspots Nature reserves Red list Near threatened species
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The 218th amino acid change of Ser to Ala in TaAGPS-7A increases enzyme activity and grain weight in bread wheat
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作者 Xiaoling Ma Xiang Ouyang +1 位作者 Dongcheng Liu Aimin Zhang 《The Crop Journal》 SCIE CSCD 2023年第1期140-147,共8页
ADP-glucose pyrophosphorylase(AGPase)influences cereal productivity.There are few reports on the function of cytosolic AGPase small subunit in bread wheat(TaAGPS).In the present study,TaAGPS was preferentially express... ADP-glucose pyrophosphorylase(AGPase)influences cereal productivity.There are few reports on the function of cytosolic AGPase small subunit in bread wheat(TaAGPS).In the present study,TaAGPS was preferentially expressed in developing endosperm during grain-filling stages in bread wheat.TaAGPS allelic variations were characterized in 143 wheat accessions by PacBio RS II sequencing.Two haplotypes(TaAGPS-7A-TG and TaAGPS-7A-CT)of TaAGPS-7A were identified and corresponding functional markers were developed,whereas no variants of TaAGPS-7B and TaAGPS-7D were detected.TaAGPS-7A was associated with thousand-kernel weight(TKW)by haplotype–trait association analysis in two populations.Near-isogenic lines(NILs)with TaAGPS-7A-TG showed higher TKW and total kernel starch content than those with TaAGPS-7A-CT,owing to the higher AGPase activity of TaAGPS-7A-TG than TaAGPS-7A-CT both in vitro and in vivo.Overexpression of TaAGPS-7A-TG in bread wheat doubled the transcription levels of TaAGPS and increased AGPase activity by 55.7%,resulting in a 3.0-g higher TKW than in the wild type(WT).Knockdown of TaAGPS led to reduced expression of TaAGPS,AGPase activity,and TKW than in the WT.Thus,owing to the 218th amino acid change of Ser to Ala in TaAGPS-7A,the favorable haplotype TaAGPS-7A-TG showed higher AGPase activity,resulting in higher kernel starch content and grain weight.This finding could be applied to increasing starch content and grain weight in bread wheat. 展开更多
关键词 Triticum aestivum Grain weight TaAGPS HAPLOTYPE Starch synthesis
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Canopy gap characteristics and spatial patterns in a subtropical forest of South China after ice storm damage 被引量:2
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作者 LIU Feng YANG Zhi-gao ZHANG Gui 《Journal of Mountain Science》 SCIE CSCD 2020年第8期1942-1958,共17页
The divergent gap characteristics and spatial patterns of canopy gaps created by natural or artificial disturbances can exert a dominant influence on forest structure and composition.However,little research has been c... The divergent gap characteristics and spatial patterns of canopy gaps created by natural or artificial disturbances can exert a dominant influence on forest structure and composition.However,little research has been conducted on the effects of ice storm damage on canopy gaps in subtropical mature forests of South China.In this study,one semi-natural site was dominated by a broad-leaf forest and two managed sites were representative of plantations with coniferous forests.Based on airborne laser scanning data and field evidence across sites,statistical analyses were used to examine gap characteristics following ice storms of moderate severity.Generalized Ripley’s K-function analysis was applied to test gap spatial patterns at a range of scales,and spatial point pattern analysis was used to quantitate the relative importance of specific influences on patterns of gap occurrence.The results revealed that the average gap size was 75.7 m^2 and that 12.2 gaps occurred per hectare.Most gaps were single-tree fall events.In addition to more gaps,the mean gap size was smaller and the shape was more complex in the semi-natural site than in two managed sites.Large differences in gap characteristics were observed among snapped,uprooted,snag,and artificial gap damage types.Gaps generally showed a clustered distribution at large scales(e.g.70 m),whereas spatial patterns varied with gap damage types at different sites.The occurrence of gaps was strongly related to slope and topographic position at the semi-natural site,whereas slope,stem density,and human accessibility(proximity to pathways)were the most important factors affecting gap occurrence at the managed sites.We suggest that gap-based silvicultural treatments and natural disturbances regimes conjoin,highlighting interactions with other factors such as microsite conditions,non-tree vegetation and more. 展开更多
关键词 Canopy gap DISTURBANCE Spatial point pattern Influence factors SILVICULTURE
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Modeling Scenic Quality of Wetland Landscape Resources in South Dongting Lake,China 被引量:1
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作者 WANG Baozhong HE Ping +1 位作者 AN Shuqing SHEN Shouyun 《Chinese Geographical Science》 SCIE CSCD 2012年第5期578-589,共12页
This study introduces a method to quantify the sceaic value of wetland landscapes and provides the guid- ance on the allocation of efforts for the purpose of preserving the most important environments. Dongting Lake, ... This study introduces a method to quantify the sceaic value of wetland landscapes and provides the guid- ance on the allocation of efforts for the purpose of preserving the most important environments. Dongting Lake, a tra-ditional tourist location, is one of the five largest freshwater lakes in China and a Grade 5A National Scenic Region. This study objectively analyzes the scenic resources of South Dongting Lake, and presents a model based on Quantifi- cation Theory I to assess wetland scenic landscapes. Employing a multilinear regression relationship between land-scape factors and their associated scenic value, we built up the Wetland Landscape Quantification Model (WLQM), which was used to classify 221 landscapes into five grades. Finally, some suggestions are proposed regarding quantita-tive assessment and its use for the sustainable development of wetland environments. 展开更多
关键词 wetland landscape scenic quality assessment Quantification Theory I South Dongting Lake
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A New Species of the Genus Protobothrops(Squamata: Viperidae) from Southern Tibet, China and Sikkim, India 被引量:1
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作者 Hujun PAN Basundhara CHETTRI +4 位作者 Daode YANG Ke JIANG Kai WANG Liang ZHANG Gernot VOGEL 《Asian Herpetological Research》 SCIE 2013年第2期109-115,共7页
A new species of the genus Protobothrops Hoge & Romano-Hoge, 1983, was described from Jilong County, southern Tibet, China, and Chungthang, northern Sikkim, India. It differs from congeners by the following character... A new species of the genus Protobothrops Hoge & Romano-Hoge, 1983, was described from Jilong County, southern Tibet, China, and Chungthang, northern Sikkim, India. It differs from congeners by the following characters: 1) relatively large body size (total length up to 1510 mm); 2) dorsal scale rows 25-25-19; 3) except for the smooth outermost row, dorsal scales are weakly keeled; 4) relatively high number of ventral (198-216) and subcaudal (65-76 pairs) scales; 5) 7-8 supralabials; 6) 11 to 13 infralabials; 7) dorsal head uniform dark brown, laterally a reddish-brown obscure postocular streak; 8) dorsum of trtmk and tail olive, with distinct black edged red brown transverse bands across the body and tail; and 9) eye from bright brown and reddish brown to mildly brown. The new species was also observed from the Haa Valley in western Bhutan. 展开更多
关键词 new species Protobothrops VIPERIDAE SQUAMATA Himalayan region
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