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Trade-off and synergy effects,driving factors,and spatial optimization of ecosystem services in the Wuding River Basin of China:A study based on the Bayesian Belief Network approach
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作者 FAN Liangwei WANG Ni +3 位作者 WANG Tingting LIU Zheng WAN Yong LI Zhiwei 《Journal of Arid Land》 2025年第12期1669-1693,共25页
The Wuding River Basin,situated in the Loess Plateau of northern China,is an ecologically fragile region facing severe soil erosion and imbalanced ecosystem service(ES)functions.However,the mechanisms driving the spat... The Wuding River Basin,situated in the Loess Plateau of northern China,is an ecologically fragile region facing severe soil erosion and imbalanced ecosystem service(ES)functions.However,the mechanisms driving the spatiotemporal evolution of ES functions,as well as the trade-offs and synergies among these functions,remain poorly understood,constraining effective watershed-scale management.To address this challenge,this study quantified four ES functions,i.e.,water yield(WY),carbon storage(CS),habitat quality(HQ),and soil conservation(SC)in the Wuding River Basin from 1990 to 2020 using the Integrated Valuation of Ecosystem Services and Tradeoff(InVEST)model,and proposed an innovative integration of InVEST with a Bayesian Belief Network(BBN)to nonlinearly identify trade-off and synergy relationships among ES functions through probabilistic inference.A trade-off and synergy index(TSI)was developed to assess the spatial interaction intensity among ES functions,while sensitivity and scenario analyses were employed to determine key driving factors,followed by spatial optimization to delineate functional zones.Results revealed distinct spatiotemporal variations:WY increased from 98.69 to 120.52 mm;SC rose to an average of 3.05×104 t/hm2;CS remained relatively stable(about 15.50 t/km2);and HQ averaged 0.51 with localized declines.The BBN achieved a high accuracy of 81.9%and effectively identified strong synergies between WY and SC,as well as between CS and HQ,while clear trade-offs were observed between WY and SC versus CS and HQ.Sensitivity analysis indicated precipitation(variance reduction of 9.4%),land use(9.8%),and vegetation cover(9.1%)as key driving factors.Spatial optimization further showed that core supply and ecological regulation zones are concentrated in the central-southern and southeastern basin,while ecological strengthening and optimization core zones dominate the central-northern and southeastern margins,highlighting strong spatial heterogeneity.Overall,this study advances ES research by combining process-based quantification with probabilistic modeling,offering a robust framework for studying nonlinear interactions,driving mechanisms,and optimization strategies,and providing a transferable paradigm for watershed-scale ES management and ecological planning in arid and semi-arid areas. 展开更多
关键词 ecosystem service functions trade-offs and synergies Bayesian Belief Network spatial pattern optimization Wuding river Basin
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Vitality variation and population structure of a riparian forest in the lower reaches of the Tarim River,NW China 被引量:8
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作者 Maierdang Keyimu Umut Halik +1 位作者 Florian Betz Choimaa Dulamsuren 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第3期742-753,共12页
Since 2000, the Chinese government has implemented emergency water diversion measures to restore the damaged riparian forest ecosystem with dominant tree species Euphrat poplar(Populus euphratica Oliv.)at the lower re... Since 2000, the Chinese government has implemented emergency water diversion measures to restore the damaged riparian forest ecosystem with dominant tree species Euphrat poplar(Populus euphratica Oliv.)at the lower reaches of the Tarim River. In the present study, comparative analysis of variations in the vitality of P. euphratica trees were made using 2005 and 2010 data to illustrate the revitalization process of riparian forest. Poplar trees within 300 m of the riverbed were positively revitalized, while the vitality of trees farther than 300 m from the river decreased. Population structure was studied to demonstrate the development of poplar community. In the first belt, the class structure for the diameter at breast height(DBH) of P. euphratica fit a logistic model, and the 2nd, 3rd and 4th belt curve fittings were close to a Gaussian model; in other plots they were bimodal. Cluster analysis of the composition of the DBH class of poplar trees demonstrated that those within 16–36 cm DBH were the most abundant(58.49% of total) in study area, under 16 cm of DBH were second(31.36%), and trees >40 cm DBH were the least abundant(10.15%). More than 80% of the trees were young and medium-sized, which means that the poplar forest community in the vicinity of the lower Tarim River is at a stable developmental stage. The abundance of juvenile trees of P. euphratica in the first and second measuring belts was 12.13% in 2005 and increased to 25.52% in 2010, which means that the emergency water transfer had a positive impact on the generation of young P. euphratica trees in the vicinity of the river. 展开更多
关键词 Lower Tarim river Riparian forest ecosystem Populus euphratica VITALITY Population structure Diameter at breast height
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Carbon sink response of terrestrial vegetation ecosystems in the Yangtze River Delta and its driving mechanism 被引量:5
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作者 ZHAO Haixia FAN Jinding +1 位作者 GU Binjie CHEN Yijiang 《Journal of Geographical Sciences》 SCIE CSCD 2024年第1期112-130,共19页
The carbon cycle of terrestrial ecosystems is influenced by global climate change and human activities.Using remote sensing data and land cover products,the spatio-temporal variation characteristics and trends of NEP ... The carbon cycle of terrestrial ecosystems is influenced by global climate change and human activities.Using remote sensing data and land cover products,the spatio-temporal variation characteristics and trends of NEP in the Yangtze River Delta from 2000 to 2020 were analyzed based on the soil respiration model.The driving influences of ecosystem structure evolution,temperature,rainfall,and human activities on NEP were studied.The results show that the NEP shows an overall distribution pattern of high in the southeast and low in the northwest.The area of carbon sinks is larger than that of the carbon sources.NEP spatial heterogeneity is significant.NEP change trend is basically unchanged or significantly better.The future change trend in most areas will be continuous decrease.Compared with temperature,NEP are more sensitive to precipitation.The positive influence of human activities on NEP is mainly observed in north-central Anhui and northern Jiangsu coastal areas,while the negative influence is mainly found in highly urbanized areas.In the process of ecosystem structure,the contribution of unchanged areas to NEP change is greater than that of changed areas. 展开更多
关键词 carbon sinks terrestrial vegetation ecosystems driving mechanisms climate change human activities ecosystem structure Yangtze river Delta
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Functions, Problems and Countermeasures of China’s Rural Ecosystems 被引量:2
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作者 HUANG Guoqin 《Journal of Landscape Research》 2019年第5期62-69,共8页
At present,the whole country is fully implementing rural revitalization strategy and actively promoting rural ecosystems development in China.From the perspective of ecology and agroecology,the main functions of rural... At present,the whole country is fully implementing rural revitalization strategy and actively promoting rural ecosystems development in China.From the perspective of ecology and agroecology,the main functions of rural ecosystem in China,the current outstanding problems,and the corresponding countermeasures and measures are discussed in the paper,in order to provide references for promoting the implementation of the strategy of rural revitalization and the sustainable development of rural ecosystem.China’s rural ecosystem has multi-functions such as carrying population,improving environment,providing products,increasing income,expanding employment and tourism,inheriting culture,popularizing science and technology,educating people,training talents,and providing places for the aged urban residents.Currently,there are still many problems and challenges in rural ecosystem in China,such as ecological destruction,waste of resources,environmental pollution,natural disasters,economic poverty,backward science and education,laggard culture and medical care,lack of public services,bad social morality,loss of villagers and disappearance of villages.In order to promote implementation of rural revitalization strategy and to promote sustainable development of rural ecosystems in China,the following measures should be taken based on the principles of integrating “tri-benefits”(economic,ecological and social benefits),gradual progress,comprehensive governance,adaptation to local conditions and long-term efforts and success.Eventually,the following measures are suggested:① enhancing awareness;② planning well;③ improving environment;④ optimizing ecological structure;⑤ improving ecological functions;⑥ improving ecological conditions;⑦ strengthening public services;⑧ improving laws and regulations;⑨ improving great investment;⑩ accelerating personnel training. 展开更多
关键词 RURAL REVITALIZATION RURAL ECOSYSTEM ECOLOGICAL structure and function Economic ECOLOGICAL and social BENEFITS Sustainable development
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Spatiotemporal evolution of water conservation function and its driving factors in the Huangshui River Basin, China
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作者 YUAN Ximin SU Zhiwei +1 位作者 TIAN Fuchang WANG Pengquan 《Journal of Arid Land》 SCIE CSCD 2024年第11期1484-1504,共21页
The Grain for Green project has had a substantial influence on water conservation in the Huangshui River Basin,China through afforestation and grassland restoration over the past two decades.However,a comprehensive un... The Grain for Green project has had a substantial influence on water conservation in the Huangshui River Basin,China through afforestation and grassland restoration over the past two decades.However,a comprehensive understanding of the spatiotemporal evolution of water conservation function and its driving factors remains incomplete in this basin.In this study,we utilized the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model to examine the spatiotemporal evolution of water conservation function in the Huangshui River Basin from 2000 to 2020.Additionally,we employed the random forest model,Pearson correlation analysis,and geographical detector(Geodetector)techniques to investigate the primary factors and factor interactions affecting the spatial differentiation of water conservation function.The findings revealed several key points.First,the high-latitude northern region of the study area experienced a significant increase in water conservation over the 21-a period.Second,the Grain for Green project has played a substantial role in improving water conservation function.Third,precipitation,plant available water content(PAWC),grassland,gross domestic product(GDP),and forest land were primary factors influencing the water conservation function.Finally,the spatial differentiation of water conservation function was determined by the interactions among geographical conditions,climatic factors,vegetation biophysical factors,and socio-economic factors.The findings have significant implications for advancing ecological protection and restoration initiatives,enhancing regional water supply capabilities,and safeguarding ecosystem health and stability in the Huangshui River Basin. 展开更多
关键词 water conservation function Grain for Green project climate change Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model random forest geographical detector(Geodetector) Huangshui river Basin
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Oasis System and Its Reasonable Development in Sangong River Watershed in North of the Tianshan Mountains,Xinjiang,China 被引量:3
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作者 LEI Jun LUO Geping +1 位作者 ZHANG Xiaolei LU Qi 《Chinese Geographical Science》 SCIE CSCD 2006年第3期236-242,共7页
Under the guide of system theory, taking the oasis in the Sangong River watershed as a case study, this paper analyzes the oasis structure and function from 4 aspects including oasis spatial structure, water resources... Under the guide of system theory, taking the oasis in the Sangong River watershed as a case study, this paper analyzes the oasis structure and function from 4 aspects including oasis spatial structure, water resources structure, vegetation structure, economic structure and their corresponding functions. The results indicate that as a typical small-scale watershed, Sangong River watershed has the relatively complete mountain-basin structure, and ecological and productive function. Because of human drastic activity the utilization rate of water resources was as high as 98.7%, and the utilization of groundwater was not reasonable, which resulted in an average annual decline of 0.353m in the water table of alluvial-diluvial-fan oasis, and an average annual increase of 0.047m in the alluvial-plain. The layout of crop and shelter forest benefits to the utilization of water and land resources. The development of oasis economy is at low level, and its eco-economic function is weak. 展开更多
关键词 oasis structure oasis function oasis economy Sangong river watershed
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Tree structure and diversity shape the biomass of primary temperate mountain forests 被引量:2
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作者 Dheeraj Ralhan Ruffy Rodrigo +14 位作者 Heather Keith Annemiek Irene Stegehuis Jakob Pavlin Yumei Jiang Milos Rydval Juliana Nogueira Alexandre Fruleux Marek Svitok Martin Mikolas Daniel Kozak Martin Dusatko Pavel Janda Oleh Chaskovsky Catalin-Constantin Roibu Miroslav Svoboda 《Forest Ecosystems》 SCIE CSCD 2024年第4期568-579,共12页
Primary forests are spatially diverse terrestrial ecosystems with unique characteristics,being naturally regenerative and heterogeneous,which supports the stability of their carbon storage through the accumulation of ... Primary forests are spatially diverse terrestrial ecosystems with unique characteristics,being naturally regenerative and heterogeneous,which supports the stability of their carbon storage through the accumulation of live and dead biomass.Yet,little is known about the interactions between biomass stocks,tree genus diversity and structure across a temperate montane primary forest.Here,we investigated the relationship between tree structure(variability in basal area and tree size),genus-level diversity(abundance,tree diversity)and biomass stocks in temperate primary mountain forests across Central and Eastern Europe.We used inventory data from726 permanent sample plots from mixed beech and spruce across the Carpathian Mountains.We used nonlinear regression to analyse the spatial variability in forest biomass,structure,and genus-level diversity and how they interact with plot-level tree age,disturbances,temperature and altitude.We found that the combined effects of genus and structural indices were important for addressing the variability in biomass across different spatial scales.Local processes in disturbance regimes and uneven tree age support forest hete rogeneity and the accumulation of live and dead biomass through the natural regeneration,growth and decay of the forest ecosystem.Structural complexities in basal area index,supporte d by genus-level abundance,positively influence total biomass stocks,which was modulated by tree age and disturbances.Spruce forests showed higher tree density and basal area than mixed beech forests,though mixed beech still contributes significantly to biomass across landscapes.Forest heterogeneity was strongly influenced by complexities in forest composition(tree genus diversity,structure).We addressed the importance of primary forests as stable carbon stores,achieved through structure and diversity.Safeguarding such ecosystems is critical for ensuring the stability of the primary forest,carbon store and biodiversity into the future. 展开更多
关键词 Biodiversity indicators Biomass carbon stock Ecosystem functioning Forest composition Primary forest structure Tree size distribution
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Evaluation of the water conservation function in the Ili River Delta of Central Asia based on the InVEST model 被引量:3
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作者 CAO Yijie MA Yonggang +2 位作者 BAO Anming CHANG Cun LIU Tie 《Journal of Arid Land》 SCIE CSCD 2023年第12期1455-1473,共19页
The Ili River Delta(IRD)is an ecological security barrier for the Lake Balkhash and an important water conservation area in Central Asia.In this study,we selected the IRD as a typical research area,and simulated the w... The Ili River Delta(IRD)is an ecological security barrier for the Lake Balkhash and an important water conservation area in Central Asia.In this study,we selected the IRD as a typical research area,and simulated the water yield and water conservation from 1975 to 2020 using the water yield module of the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model.We further analyzed the temporal and spatial variations in the water yield and water conservation in the IRD from 1975 to 2020,and investigated the main driving factors(precipitation,potential evapotranspiration,land use/land cover change,and inflow from the Ili River)of the water conservation variation based on the linear regression,piecewise linear regression,and Pearson's correlation coefficient analyses.The results indicated that from 1975 to 2020,the water yield and water conservation in the IRD showed a decreasing trend,and the spatial distribution pattern was"high in the east and low in the west";overall,the water conservation of all land use types decreased slightly.The water conservation volume of grassland was the most reduced,although the area of grassland increased owing to the increased inflow from the Ili River.At the same time,the increased inflow has led to the expansion of wetland areas,the improvement of vegetation growth,and the increase of regional evapotranspiration,thus resulting in an overall reduction in the water conservation.The water conservation depth and precipitation had similar spatial distribution patterns;the change in climate factors was the main reason for the decline in the water conservation function in the delta.The reservoir in the upper reaches of the IRD regulated runoff into the Lake Balkhash,promoted vegetation restoration,and had a positive effect on the water conservation;however,this positive effect cannot offset the negative effect of enhanced evapotranspiration.These results provide a reference for the rational allocation of water resources and ecosystem protection in the IRD. 展开更多
关键词 water conservation function water yield Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model climate change land use/land cover change(LUCC) Ili river Delta Lake Balkhash
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Comprehensive evaluation and stability analysis of ecosystem quality of Yellow River Basin during 1980–2019 被引量:2
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作者 Zhiwei Cao Wensi Ma +1 位作者 Chao Zhang Peiying Tan 《River》 2023年第2期239-248,共10页
Quality and stability are the basic characteristics of ecosystems,reflecting their structure,process,functional integrity,ability to resist disturbance,self-regulation,and dynamic balance.The quantitative description ... Quality and stability are the basic characteristics of ecosystems,reflecting their structure,process,functional integrity,ability to resist disturbance,self-regulation,and dynamic balance.The quantitative description of ecosystem quality and stability is an indispensable and important task to promote the ecological protection and high-quality development of the Yellow River Basin as a major national strategy.In this study,an index evaluation system was constructed from the perspective of system governance,considering the special characteristics of the Yellow River Basin,and an entropy weight model was used to establish a multi-indicator long time series ecosystem quality evaluation index(EQI)to quantitatively describe the ecological quality changes in the Yellow River Basin over 40 years.The dissipative structure theory and Brussels apparatus model were used to establish quantitative indicators and methods,and provide ideas for the study of ecosystem homeostasis transformation in the Yellow River basin.This study found that:(1)the average EQI value of the Yellow River Basin ecosystem for 40 years was 63.96,the maximum and minimum values were 69.65 and 59.45,respectively;the overall quality showed an oscillating trend of improvement,with an annual increase of 0.03,and the spatial distribution was better in the downstream than in the midstream,and in the midstream than in the upstream;(2)The key factors influencing the system changed gradually from the total water consumption and total annual precipitation in the basin in the early stage to the average income of residents in the last 10 years.(3)The system steady-state transition force values from 1980 to 2019 were all<0,the steady-state conversion force of the Yellow River Basin ecosystem was low,but the overall trend was oscillating upward,and the overall trend was getting closer to the critical condition of steady-state conversion. 展开更多
关键词 dissipative structure ecosystem quality entropy weight STABILITY Yellow river Basin
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Ecological Disturbance Caused by Land Use Change in the Karst Area,China:A Combined Structural and Functional Perspective
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作者 ZHOU Zhongfa SUN Yaopeng +4 位作者 FANG Min SUN Jianwei YANG Pingping KONG Jie DING Shengjun 《Chinese Geographical Science》 2025年第4期755-768,共14页
Land use change is a fundamental factor affecting ecosystem’s structures and functions.However,few studies have explored the ecological disturbance caused by land use change from a combined structural and functional ... Land use change is a fundamental factor affecting ecosystem’s structures and functions.However,few studies have explored the ecological disturbance caused by land use change from a combined structural and functional perspective.In this study,the ecological structural disturbance index(SDI)and functional disturbance index(FDI)were introduced to quantitatively evaluate ecological disturbance caused by land use change in a typical karst area—Huangping County,Guizhou Province,China during 2009–2019.Results show that although the area of ecological land increased during past 10 yr,there had been a fragmentation trend of ecological land.Agricultural occupation was more severe than construction encroachment on ecological land.The grids with negative structural disturbance were consistent with areas of obvious dynamic loss and gain of ecological land.Ecological fragmentation had a greater impact than habitat gain in grids with negative structural disturbance.The ecosystem service functions of supply,adjustment,support,and culture were obviously affected by land use change,and the total FDI reflects the trade-off among them.Negative FDI values were easily observed in the rocky desertification area or water and soil loss area.The combination analysis of the SDI and FDI indicated the characteristic of codirectional ecologically structural and functional disturbance in the majority of grids.The findings improve our understanding of multiple relationships among ecological disturbances and provide valuable information for guiding land use activities. 展开更多
关键词 land use ecological land ecosystem service function ecological structural disturbance index(SDI) functional disturbance index(FDI) karst area Huangping County China
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Impact of nitrogen addition and precipitation on net ecosystem exchange in the Urat desert steppe, China
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作者 ZHANG Xiaoxue YUE Ping +4 位作者 SONG Zhaobin ZUO Xiaoan ZHANG Rui WANG Zhengjiaoyi QIAO Jingjuan 《Journal of Arid Land》 2025年第3期337-349,共13页
Amid global climate change, rising levels of nitrogen(N) deposition have attracted considerable attention for their potential effects on the carbon cycle of terrestrial ecosystems. The desert steppes are a crucial yet... Amid global climate change, rising levels of nitrogen(N) deposition have attracted considerable attention for their potential effects on the carbon cycle of terrestrial ecosystems. The desert steppes are a crucial yet vulnerable ecosystem in arid areas, but their response to the combination of N addition and precipitation(a crucial factor in arid areas) remains underexplored. This study systematically explored the impact of N addition and precipitation on net ecosystem exchange(NEE) in a desert steppe in northern China. Specifically, we conducted a 2-a experiment from 2022 to 2023 with eight N addition treatments in the Urat desert steppe of Inner Mongolia Autonomous Region, China, to examine changes in NEE and explore its driving factors. The structural equation model(SEM) and multiple regression model were applied to determine the relationship of NEE with plant community characteristics and soil physical-chemical properties. Statistical results showed that N addition has no significant effect on NEE.However, it has a significant impact on the functional traits of desert steppe plant communities. SEM results further revealed that N addition has no significant effect on NEE in the desert steppe, whereas annual precipitation can influence NEE variations. The multiple regression model analysis indicated that plant functional traits play an important role in explaining the changes in NEE, accounting for 62.15% of the variation in NEE. In addition, plant height, as an important plant functional trait indicator, shows stronger reliability in predicting the changes in NEE and becomes a more promising predictor. These findings provide valuable insights into the complex ecological mechanisms governing plant community responses to precipitation and nutrient availability in the arid desert steppes, contributing to the improved monitoring and prediction of desert steppe ecosystem responses to global climate change. 展开更多
关键词 nitrogen addition net ecosystem exchange plant functional traits structural equation model(SEM) multiple regression model Urat desert steppe
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Selective logging enhances ecosystem multifunctionality via increase of functional diversity in a Pinus yunnanensis forest in Southwest China 被引量:3
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作者 Xiaobo Huang Shuaifeng Li Jianrong Su 《Forest Ecosystems》 SCIE CSCD 2020年第4期733-745,共13页
Background:The impacts of selective logging on ecosystem multifunctionality(EMF)remain largely unexplored.In this study,we analyzed the response of nine variables related to four ecosystem functions(i.e.nutrient cycli... Background:The impacts of selective logging on ecosystem multifunctionality(EMF)remain largely unexplored.In this study,we analyzed the response of nine variables related to four ecosystem functions(i.e.nutrient cycling,soil carbon stocks,decomposition,and wood production)to five selective logging intensities in a Pinus yunnanensisdominated forest.We included a control group with no harvest to evaluate the potential shifts in EMF of the P.yunnanensis forests.We also assessed the relationship between above-and belowground biodiversity and EMF under these different selective logging intensities.Additionally,we evaluated the effects of biotic and abiotic factors on EMF using a structural equation modeling(SEM)approach.Results:Individual ecosystem functions(EFs)all had a significant positive correlation with selective logging intensity.Different EFs showed different patterns with the increase of selective logging intensity.We found that EMF tended to increase with logging intensity,and that EMF significantly improved when the stand was harvested at least twice.Both functional diversity and soil moisture had a significant positive correlation with EMF,but soil fungal operational taxonomic units(OTUs)had a significant negative correlation with EMF.Based on SEM,we found that selective logging improved EMF mainly by increasing functional diversity.Conclusion:Our study demonstrates that selective logging is a good management technique from an EMF perspective,and thus provide us with potential guidelines to improve forest management in P.yunnanensis forests in this region.The functional diversity is maximized through reasonable selective logging measures,so as to enhance EMF. 展开更多
关键词 BIODIVERSITY Ecosystem multifunctionality functional traits Pinus yunnanensis Soil enzymatic activity Structural equation modeling
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Estimation of Turbulent Kinetic Energy Dissipation Rate in the Bottom Boundary Layer of the Pearl River Estuary
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作者 刘欢 吴超羽 任杰 《China Ocean Engineering》 SCIE EI 2011年第4期669-678,共10页
A structure function approach is applied to estimate the turbulent kinetic energy (TKE) dissipation rate in the bottom boundary layer of the Pearl River Estuary (PRE). Simultaneous measurements with an acoustic Do... A structure function approach is applied to estimate the turbulent kinetic energy (TKE) dissipation rate in the bottom boundary layer of the Pearl River Estuary (PRE). Simultaneous measurements with an acoustic Doppler velocimeter (ADV) supplied independent data for the verification of the structure function method. The results show that, 1) the structure function approach is reliable and successfully applied method to estimate the TKE dissipation rate. The observed dissipation rates range between 8.3 ×10^-4 W/kg and 4.9× 10^-6 W/kg in YM01 and between 3.4×10^-4 W/kg and 4.8×10^-7 W/kg in YM03, respectively, while exhibiting a strong quarter-diurnal variation. 2) The balance between the shear production and viscous dissipation is better achieved in the straight river. This first-order balance is significantly broken in the estuary by non-shear production/dissipation due to wave-induced fluctuations. 展开更多
关键词 structure function turbulent kinetic energy dissipation rate bottom boundary layer Pearl river Estuary
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Tree-based attributes of large trees more effectively regulate aboveground carbon stock than trait-based ones in temperate deciduous forests
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作者 Maryam Kazempour Larsary Hassan Pourbabaei +2 位作者 Ali Salehi Rasoul Yousefpour Arshad Ali 《Plant Diversity》 2025年第4期653-665,共13页
In forests,a few large trees(L-trees)versus small-medium trees(S-trees)are often considered the major reservoir of aboveground carbon stock(AGCS).Here,we hypothesize that tree species'functional strategies regulat... In forests,a few large trees(L-trees)versus small-medium trees(S-trees)are often considered the major reservoir of aboveground carbon stock(AGCS).Here,we hypothesize that tree species'functional strategies regulate AGCS by tree sizes in temperate deciduous forests across local scale environmental gradients.Using data from 99 plots,we modelled the multivariate effects of the tree-based(tree diversity,stand density and multidimensional tree size inequality)versus the trait-based(multi-trait diversity and single-trait dominance)attributes of L-trees versus S-trees,along topographic and soil conditions,to predict AGCS through four L-trees threshold size(i.e.,≥50 cm fixed-diameter,top 95th percentile,≥top 50%cumulative AGCS descending-ranked ordered,and mean threshold size)approaches.The tree-based and trait-based attributes of L-trees and S-trees shaped species co-occurrence processes but L-trees regulated AGCS more effectively(31.29-93.20%)than S-trees and abiotic factors across four thereshold size approaches and two concepts.Although L-trees threshold size and tree-based attributes mattered for AGCS,the dominant resource-acquisitive strategy of structurally complex L-trees having higher specific leaf area but lower leaf dry matter content and lesser multi-trait dispersion could promote AGCS better than the resource-conservative strategy(low specific leaf area)of S-trees.Capturing tree species'functional strategies,synergies and trade-offs across tree sizes can enhance our understanding of how to achieve nature-based carbon neutrality and lessen climate change.Thus,forest management and restoration initiatives should prioritize high-functioning tree species with dominant productive traits while conserving multi-trait diversified species in temperate deciduous forests. 展开更多
关键词 Ecological mechanisms Ecosystem functioning Plant physiological characteristics Species diversity Soil nutrients Stand structure
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Crust and uppermost mantle structure of the Ailaoshan-Red River fault from receiver function analysis 被引量:11
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作者 XU Mingjie1, WANG Liangshu1, LIU Jianhua2, ZHONG Kai1, LI Hua1, HU Dezhao1 & XU Zhen1 1. Department of Earth Sciences, Nanjing University, Nanjing 210093, China 2. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 《Science China Earth Sciences》 SCIE EI CAS 2006年第10期1043-1052,共10页
S-wave velocity structure beneath the Ailaoshan-Red River fault was obtained from receiver functions by using teleseismic body wave records of broadband digital seismic stations. The average crustal thickness, Vp/Vs r... S-wave velocity structure beneath the Ailaoshan-Red River fault was obtained from receiver functions by using teleseismic body wave records of broadband digital seismic stations. The average crustal thickness, Vp/Vs ratio and Poisson’s ratio were also estimated. The results indicate that the interface of crust and mantle beneath the Ailaoshan-Red River fault is not a sharp velocity discontinuity but a characteristic transition zone. The velocity increases relatively fast at the depth of Moho and then increases slowly in the uppermost mantle. The average crustal thickness across the fault is 36―37 km on the southwest side and 40―42 km on the northeast side, indicating that the fault cuts the crust. The relatively high Poisson’s ratio (0.26―0.28) of the crust implies a high content of mafic materials in the lower crust. Moreover, the lower crust with low velocity could be an ideal position for decoupling between the crust and upper mantle. 展开更多
关键词 RECEIVER function Ailaoshan-Red river fault velocity structure Poisson's ratio CRUST and UPPER mantle.
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The Ecosystem Service Function of Shandong Xiajin Yellow River Ancient Mulberry Trees System and Its Effect on Regional Ecosystem 被引量:2
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作者 孙雪萍 王斌 +1 位作者 刘某承 刘伟玮 《Journal of Resources and Ecology》 CSCD 2016年第3期223-230,共8页
The Shandong Xiajin Yellow River Ancient Mulberry Trees System is a model of desertification control in the floor area in the Luxibei Plain,and of sustainable development.The current study about ancient mulberry trees... The Shandong Xiajin Yellow River Ancient Mulberry Trees System is a model of desertification control in the floor area in the Luxibei Plain,and of sustainable development.The current study about ancient mulberry trees in Xiajin county is mainly qualitative representation,lack of quantitative research.In addition,the relevant important ecological functional assessment should not only confine to quantitative assessment which illustrate the current condition,but also analyze the eco-service changes,derived from ecosystem structure develop,from the time dimension.Based on quantitative eco-service assessment of the ancient mulberry tree group,this paper intend to conduct a comprehensive analysis of ecological functions of ancient mulberry group focuses on the perspective of system structure and function evolution.Quantitative evaluation results show that the system has significant eco-efficiency in water conservation,reducing sediment loss,adjust atmosphere,etc.On timescale,thanks to mulberry cultivation,ecosystem structure and services have also undergone a corresponding change.In ecosystem structure:Planting pioneer trees such as mulberries and other species which can tolerate hostile site conditions,improves the micro-environment.This makes it possible for other crops to grow.The mixed forests and the combination of forestry and agriculture protect biodiversity.What's more,they make the structure of the ecosystems more robust,giving full play to their functions.In terms of ecosystem services:ecosystem services of Xiajin Yellow River Ancient Mulberry Trees have shown diversified development.And its main function has transferred from supply products to leisure and entertainment functions. 展开更多
关键词 Yellow river old river course ancient mulberry trees ecosystem services ecosystem structure evolution eco-service change
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Review of forest ecology studies in China 被引量:3
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作者 王庆礼 邓红兵 +1 位作者 王绍先 李杨 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第3期231-234,252,共4页
As the most important type or component in the terrestrial ecosystems, forest ecosystem makes its role obviously prominent and important on environment and human being. It possesses non-substitutable functions in the ... As the most important type or component in the terrestrial ecosystems, forest ecosystem makes its role obviously prominent and important on environment and human being. It possesses non-substitutable functions in the process of sustainable development. However, due to the complexity of the forest ecosystem and the relatively delay or lack of the related research technology, the science is still in the case of immature and questions. This paper summarized and reviewed briefly the development and the present case of the forest ecology, then pointed out the existing problems in the forest ecosystem researches. In the end, we discussed several fields that need to pay more attention to in future researches. 展开更多
关键词 FOREST ECOSYSTEM Forest ecology structure and function MANAGEMENT HEALTH WATERSHED
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Regionalization Methodology Systems of Aquatic Ecosystems in China and the Case Study of Huaihe River Basin 被引量:1
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作者 左其亭 梁静静 窦明 《Journal of Resources and Ecology》 CSCD 2010年第4期375-382,共8页
本文提出的水生态区划方法体系包括指导思想、基本原则、分区方法、命名与编码规则几个部分。其核心指导思想是科学发展观及人与自然和谐的理念;基本原则有区域相关性原则、协调原则、主导功能原则和分及区划原则;分区方法、命名与编码... 本文提出的水生态区划方法体系包括指导思想、基本原则、分区方法、命名与编码规则几个部分。其核心指导思想是科学发展观及人与自然和谐的理念;基本原则有区域相关性原则、协调原则、主导功能原则和分及区划原则;分区方法、命名与编码规则则随分区等级和研究尺度而异。本文采用2级分区的思路,提出了全国水生态区划分方案,包括6个水生态一级区和34个水生态二级区。基于以下3类7种水生态服务功能:水生态保育类(包括水源涵养、水土保持和物种保护),水生态调控类(包括洪水调蓄和生境维持),水生态服务类(包括产品提供和景观保障),以淮河流域为例,将3级水生态区划方法应用于流域尺度。在实例区共划分出2个水生态一级区、3个水生态二级区和21个水生态三级区。 展开更多
关键词 aquatic ecoregion regionalization approach aquatic ecosystem service function regionalization scheme Huaihe river Basin
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Soil nutrients drive the spatial variability of wetland productivity along degradation gradients through plant functional traits
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作者 Junxiang Ding Mingli Zhang +11 位作者 Xiaowen Zeng Ming Dou Wenjing Ge Yingshu Cao Qingbin Mi Jihua Wang Fengmin Lu Liang Zhao Deliang Kong Huajun Yin Lin Wang Guangsheng Zhou 《Journal of Plant Ecology》 2025年第2期328-342,共15页
The stability mechanisms of ecosystem functions have been a hot topic in ecology. However, in wetland ecosystems, the mechanisms by which biotic and abiotic factors interact to affect ecosystem stability in changing e... The stability mechanisms of ecosystem functions have been a hot topic in ecology. However, in wetland ecosystems, the mechanisms by which biotic and abiotic factors interact to affect ecosystem stability in changing environments remain largely unclear. This study investigated the key factors and underlying mechanisms that regulate the spatial variability of wetland productivity by measuring community productivity, multiple components of biodiversity (i.e. species diversity, community functional composition and diversity) and environmental factors along a well-characterized gradient of wetland degradation in the lower reaches of the Yellow River. The results showed that the spatial variability of productivity in wetlands increased with intensified degradation. The spatial variability of wetland productivity was not related to species richness but was mainly affected by changes in community functional composition and diversity. Furthermore, degradation-induced changes in soil nutrients drove the spatial variability of productivity to increase with shifts in functional composition towards more conservative traits (i.e. higher leaf dry matter content and root tissue density), and to decrease with higher functional trait diversity. These findings reveal the driving mechanism of spatial variability in wetland productivity under degradation, and suggest that reduced nutrient availability, by altering plant resource strategies, can affect the spatial reliability of key ecosystem functions in wetlands. 展开更多
关键词 BIODIVERSITY community functional composition plant functional traits productivity spatial variability species richness the Yellow river wetland ecosystems
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Development and applications of functional gene microarrays in the analysis of the functional diversity,composition,and structure of microbial communities 被引量:10
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作者 Zhili HE Joy DVAN NOSTRAND +1 位作者 Ye DENG Jizhong ZHOU 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2011年第1期1-20,共20页
Functional gene arrays(FGAs)are a special type of microarrays containing probes for key genes involved in microbial functional processes,such as biogeochemical cycling of carbon,nitrogen,sulfur,phosphorus,and metals,b... Functional gene arrays(FGAs)are a special type of microarrays containing probes for key genes involved in microbial functional processes,such as biogeochemical cycling of carbon,nitrogen,sulfur,phosphorus,and metals,biodegradation of environmental contaminants,energy processing,and stress responses.GeoChips are considered as the most comprehensive FGAs.Experimentally established probe design criteria and a computational pipeline integrating sequence retrieval,probe design and verification,array construction,data analysis,and automatic update are used to develop the GeoChip technology.GeoChip has been systematically evaluated and demonstrated to be a powerful tool for rapid,specific,sensitive,and quantitative analysis of microbial communities in a high-throughput manner.Several generations of GeoChip have been developed and applied to investigate the functional diversity,composition,structure,function,and dynamics of a variety of microbial communities from different habitats,such as water,soil,marine,bioreactor,human microbiome,and extreme ecosystems.GeoChip is able to address fundamental questions related to global change,bioenergy,bioremediation,agricultural operation,land use,human health,environmental restoration,and ecological theories and to link the microbial community structure to environmental factors and ecosystem functioning. 展开更多
关键词 functional gene arrays(FGAs) GeoChip microbial communities functional diversity/composition/structure environmental factor ecosystem functioning
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