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Restoration boosts soil P-cycle multifunctionality in karst ecosystems by modulating soil properties and rare bacterial taxa
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作者 Fujing Pan Xuan Yu +4 位作者 Yueming Liang Peilei Hu Kelin Wang Wei Zhang Qian Yang 《Journal of Integrative Agriculture》 2026年第2期513-528,共16页
Phosphorus (P) is an essential nutrient element that is critical for plant growth and ecosystem functionality.The soil P cycle plays multiple roles,such as sustaining plant growth and productivity,regulating nutrient ... Phosphorus (P) is an essential nutrient element that is critical for plant growth and ecosystem functionality.The soil P cycle plays multiple roles,such as sustaining plant growth and productivity,regulating nutrient balance within ecosystems,and enhancing ecosystem adaptability and resilience.This cycle is influenced by factors such as the restoration approach and microbial community dynamics.However,the extent to which the restoration approach alters the P cycle in karst ecosystems and the underlying microbial mechanisms remain poorly understood.The P-cycle multifunctionality index (P-cycle MFI) serves as a comprehensive indicator for evaluating soil P cycle function,and it provides insights into changes in the P cycle between different restoration approaches.To investigate the shifts in soil P-cycle MFI and microbial mechanisms between different restoration approaches,we analyzed soil available P (AP),total P (TP),microbial biomass P (MBP),and the activities of acid phosphatase (ACP) and alkaline phosphatase (ALP).These data were used to calculate the P-cycle MFI by averaging the Z-scores between two restoration approaches(artificial restoration of forest (AF) and natural restoration of forest (NF)) and a control (cropland,CP) at six subtropical karst ecosystem sites in China.We also determined the soil organic carbon (SOC),exchangeable calcium (Ca) and magnesium (Mg),pH,bulk density (BD),microbial biomass C (MBC),and microbial biomass nitrogen (MBN),as well as the community structure,relative abundance,diversity indices,and co-occurrence networks of phoD-harboring bacteria.The results showed that the community structure of phoD-harboring bacteria varied significantly among AF,NF,and CP and across different temperature gradients.These bacteria exhibited increasing complexity and tightness in co-occurrence networks from CP to AF and then to NF,along with the ACP and ALP activities,but not the TP and AP contents.The P-cycle MFI values were significantly higher in NF compared to AF and CP,and the variation was significantly explained by restoration approach,temperature,MBC,MBN,SOC,exchangeable Ca,BD,community structure of phoD-harboring bacteria,and exchangeable Mg.Furthermore,natural restoration had a more substantial impact on the P-cycle MFI than temperature by enhancing SOC,microbial biomass,the complexity and co-occurrence network tightness of the phoD-harboring bacterial community structure,and ACP and ALP activities,but it reduced soil BD.The rare genera of phoD-harboring bacteria significantly influenced the variation of soil P-cycle MFI compared to the dominant genera.This study highlights the importance of rare genera of phoD-harboring bacteria in driving soil P-cycle multifunctionality in karst ecosystems,with natural restoration being more effective than artificial methods for enhancing soil organic matter and microbial community complexity. 展开更多
关键词 karst ecosystem RESTORATION community phoD-harboring bacteria P-cycle multifunctionality rare taxa
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Grassland ecosystems of Tajikistan:Plant species diversity,ecological restoration,and sustainable management
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作者 Hikmat HISORIEV LI Yaoming +3 位作者 HUANG Wenjun FAN Lianlian Mekhrovar OKHONNIYOZOV MA Xuexi 《Regional Sustainability》 2026年第1期23-36,共14页
Livestock farming is a critical pillar of Tajikistan’s national economy and livelihood security.However,significant economic challenges in the country have led to the degradation of grassland ecosystems.This degradat... Livestock farming is a critical pillar of Tajikistan’s national economy and livelihood security.However,significant economic challenges in the country have led to the degradation of grassland ecosystems.This degradation has not only reduced the productivity of grassland ecosystems but also severely impacted their ecological functions.A particularly concerning consequence is the threat to biodiversity,as the survival and persistence of endemic,rare,and endangered plant species are at serious risk,thereby diminishing the value of species’genetic resources.Based on the data from multiple sources such as literature reviews,field observations,and national statistics,this study employed a systematic literature review and meta-analysis to investigate the current status,causes of degradation,and restoration measures for grassland ecosystems in Tajikistan.The results revealed that Tajikistan’s grassland ecosystems support exceptionally high plant species diversity,comprising over 4500 vascular plant species,including nearly 1500 endemic and sub-endemic taxa that constitute a unique genetic reservoir.These ecosystems are experiencing severe degradation,characterized by significantly reduced vegetation cover and declining species richness.Palatable forage species are increasingly being displaced by unpalatable,thorny,and poisonous species.The primary drivers of degradation include excessive grazing pressure,which disrupts plant reproductive cycles and regeneration capacity,habitat fragmentation due to urbanization and infrastructure development,and uncontrolled exploitation of medicinal and edible plants.Climate change,particularly rising temperatures and altered precipitation patterns,further exacerbates these anthropogenic pressures.Ecological restoration experiments suggested that both ecosystem productivity and plant species diversity are significantly enhanced by systematic reseeding trials using altitude-adapted native species.These findings underscore the necessity of establishing scientifically grounded approaches for ecological restoration. 展开更多
关键词 Grassland ecosystem degradation Plant communities OVERGRAZING Ecological restoration Climate change TAJIKISTAN
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Evaluating climate-induced productivity of typical ecosystems of the eastern margin of the Qinghai-Tibet Plateau
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作者 ZHENG Huazhu YAO Zhengyu +6 位作者 LU Jungang WU Yongjiao YE Quan ZHAO Hongfei OUYANG Maolin Claudio ODELANG HE Hongming 《Journal of Geographical Sciences》 2026年第1期107-128,共22页
Ecosystems along the eastern margin of the Qinghai-Tibet Plateau(EQTP)are highly fragile and extremely sensitive to climate change and human disturbances.To quantitatively assess climate-induced ecosystem responses,th... Ecosystems along the eastern margin of the Qinghai-Tibet Plateau(EQTP)are highly fragile and extremely sensitive to climate change and human disturbances.To quantitatively assess climate-induced ecosystem responses,this study proposes a Climate-Induced Productivity Index(CIPI)based on the Super Slack-Based Measure(Super-SBM)model using remote sensing data from 2001 to 2020.The results reveal persistently low CIPI values(0.47-0.53)across major ecosystem types,indicating widespread vulnerability to climatic variability.Among these ecosystems,forests exhibit the highest CIPI(0.55),followed by shrublands(0.54),croplands(0.53),grasslands(0.51),and barelands(0.43).The Theil index analysis further demonstrates significant intra-group disparities,suggesting that extreme climatic events amplify CIPI heterogeneity.Moreover,the dominant environmental drivers differ among ecosystem types:the Palmer Drought Severity Index(PDSI)primarily constrains grassland productivity,solar radiation(SRAD)strongly influences shrub and cropland systems,whereas subsurface factors exert greater control in forested regions.This study provides a quantitative framework for evaluating climate-ecosystem interactions and offers a scientific basis for long-term ecological monitoring and security planning across the EQTP. 展开更多
关键词 climate-induced productivity index(CIPI) Super-SBM model ecosystem vulnerability environmental drivers eastern margin of Qinghai-Tibet Plateau
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New horizons in the exploration of polar biodiversity,ecosystems,and genetic resources
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作者 JI Mukan LIAO Li +3 位作者 Maggie C.Y.LAU VETTER SHAO Changwei ZHANG Xiying Ben LUISI 《Advances in Polar Science》 2025年第4期265-267,共3页
The polar regions host one of the harshest and most unique ecosystems on Earth.These habitats,encompassing the Arctic and the Antarctic and from deep-marine sediments to glacial ice/ice sheets,represent one of the fin... The polar regions host one of the harshest and most unique ecosystems on Earth.These habitats,encompassing the Arctic and the Antarctic and from deep-marine sediments to glacial ice/ice sheets,represent one of the final frontiers of terrestrial biological exploration.Traditionally viewed as desolate,ice-covered lands,polar regions are now recognized as vibrant,complex,and highly sensitive ecosystems. 展开更多
关键词 terrestrial biological explorationtraditionally BIODIVERSITY deep marine sediments ecosystems polar regions ARCTIC ANTARCTIC genetic resources
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Valuing ecosystem products and realization pathways for farmland ecosystems in inland river basins:A case study of Zhangye City
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作者 JunXia Miao WenDing Jian +3 位作者 Na Wu Xiang Pan XueMei Liu XiaoYu Song 《Research in Cold and Arid Regions》 2025年第6期413-426,共14页
Farmland ecosystems are the primary ecosystem type in inland river basins,providing the biological and material basis for human development and survival.The foundation for monetizing the value of agricultural ecologic... Farmland ecosystems are the primary ecosystem type in inland river basins,providing the biological and material basis for human development and survival.The foundation for monetizing the value of agricultural ecological products and transforming green mountains into gold mountains is the precise assessment of ecosystem products in specific geographic units(VEP)within farmland ecosystems,which elucidates regional agricultural resource endowments and spatial distribution.However,agricultural ecological products face challenges in valuation,trading,and monetization,and research on pathways for their value transformation remains limited.This study uses Zhangye City in inland river basins as an example to construct a catalog of farmland ecosystem ecological products and explores VEP accounting methods based on multi-source data,including statistical,remote sensing,and monitoring data,at the city and county scales,and analyzes differentiated value transformation pathways according to the attributes of various agricultural ecological products.The results show that material supply value ranks highest among the VEP of farmland ecosystems in inland river basins,followed by regulatory services,while recreational agriculture value ranks lowest.The ranking of VEP varies from the ranking of farmland ecosystem area,with available agricultural water being a major constraint on the VEP of farmland ecosystems in inland river basins.Regional climate,geographic position,and transportation are linked to the value of agricultural ecosystem products within material supply products.Precipitation,soil structure,and cropping patterns are linked to the value of agricultural ecosystem products within regulatory services.The local cultural resources and tourism infrastructure are linked to the value of agricultural ecosystem products within cultural services.Regarding the pathways for achieving the value of agricultural ecological products,market-oriented strategies dominate the mainstay of material supply products,government-led mechanisms are pivotal for regulatory service products,and a combination of government and market strategies is essential for cultural service products. 展开更多
关键词 Inland river basin Farmland ecosystems The value of ecosystem product in specific geographic units(VEP) Realization pathways Zhangye city
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Parameter sensitivity analysis and optimization of carbon and water fluxes in grassland ecosystems based on the Biome-BGCMuSo Model
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作者 TIAN Yujie JING Changqing +2 位作者 SHAO Yuqing WANG Xiaoyi ZHU Yuhao 《Journal of Mountain Science》 2025年第11期3964-3977,共14页
Accurate quantification of carbon and water fluxes dynamics in arid and semi-arid ecosystems is a critical scientific challenge for regional carbon neutrality assessments and sustainable water resource management.In t... Accurate quantification of carbon and water fluxes dynamics in arid and semi-arid ecosystems is a critical scientific challenge for regional carbon neutrality assessments and sustainable water resource management.In this study,we developed a multi-flux global sensitivity discriminant index(D_(sen))by integrating the Biome-BGCMuSo model with eddy covariance flux observations.This index was combined with a Bayesian optimization algorithm to conduct parameter optimization.The results demonstrated that:(1)Sensitivity analysis identified 13 highly sensitive parameters affecting carbon and water fluxes.Among these,the canopy light extinction coefficient(k)and the fraction of leaf N in Rubisco(FLNR)exhibited significantly higher sensitivity to carbon fluxes(GPP,NEE,Reco;D_(sen)>10%)compared to water flux(ET).This highlights the strong dependence of carbon cycle simulations on vegetation physiological parameters.(2)The Bayesian optimization framework efficiently converged 30 parameter spaces within 50 iterations,markedly improving carbon fluxes simulation accuracy.The Kling-Gupta efficiency(KGE)values for Gross Primary Production(GPP),Net Ecosystem Exchange(NEE),and Total Respiration(Reco)increased by 44.94%,69.23%and 123%,respectively.The optimization prioritized highly sensitive parameters,underscoring the necessity of parameter sensitivity stratification.(3)The optimized model effectively reproduced carbon sink characteristics in mountain meadows during the growing season(cumulative NEE=-375 g C/m^(2)).It revealed synergistic carbon-water fluxes interactions governed by coupled photosynthesis-stomatal pathways and identified substrate supply limitations on heterotrophic respiration.This study proposes a novel multi-flux sensitivity index and an efficient optimization framework,elucidating the coupling mechanisms between vegetation physiological regulation(k,FLNR)and environmental stressors(VPD,SWD)in carbonwater cycles.The methodology offers a practical approach for arid ecosystem model optimization and provides theoretical insights for grassland management through canopy structure regulation and water-use efficiency enhancement. 展开更多
关键词 Carbon flux Water flux Biome-BGCMuSo model Sensitivity analysis Bayesian optimization Grassland ecosystems
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Influence of nitrogen inputs on biomass allocation strategies of dominant plant species in sandy ecosystems
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作者 CHENG Li ZHAN Jin +1 位作者 NING Zhiying LI Yulin 《Journal of Arid Land》 2025年第8期1118-1146,共29页
Understanding how dominant plants respond to nitrogen(N)addition is critical for accurately predicting the potential effects of N deposition on ecosystem structure and functionality.Biomass partitioning serves as a va... Understanding how dominant plants respond to nitrogen(N)addition is critical for accurately predicting the potential effects of N deposition on ecosystem structure and functionality.Biomass partitioning serves as a valuable indicator for assessing plant responses to environmental changes.However,considerable uncertainty remains regarding how biomass partitioning shifts with increasing N inputs in sandy ecosystems.To address this gap,we conducted a greenhouse N fertilization experiment in April 2024,using seeds from 20 dominant plant species in the Horqin Sandy Land of China representing 5 life forms:annual grasses,annual forbs,perennial grasses,perennial forbs,and shrubs.Six levels of N addition(0.0,3.5,7.0,14.0,21.0,and 49.0 g N/(m2•a),referred to as N0,N1,N2,N3,N4,and N5,respectively)were applied to investigate the effects of N inputs on biomass partitioning.Results showed that for all 20 dominant plant species,the root biomass:shoot biomass(R:S)consistently declined across all N addition treatments(P<0.050).Concurrently,N addition led to a 23.60%reduction in root biomass fraction,coupled with a 12.38%increase in shoot biomass fraction(P<0.050).Allometric partitioning analysis further indicated that N addition had no significant effect on the slopes of the allometric relationships(leaf biomass versus root biomass,stem biomass versus root biomass,and shoot biomass versus root biomass).This suggests that plants can adjust resource investment—such as allocating more resources to shoots—to optimize growth under favorable conditions without disrupting functional trade-offs between organs.Among different life forms,annual grasses,perennial grasses,and annual forbs exhibited increased allocation to aboveground biomass,enhancing productivity and potentially altering community composition and competitive hierarchies.In contrast,perennial forbs and shrubs maintained stable biomass partitioning across all N addition levels,reflecting conservative resource allocation strategies that support long-term ecosystem resilience in nutrient-poor environments.Taken together,these findings deepen our understanding of how nutrient enrichment influences biomass allocation and ecosystem dynamics across different plant life forms,offering practical implications for the management and restoration of degraded sandy ecosystems. 展开更多
关键词 N addition biomass accumulation biomass partitioning fraction allometric relationship plant life form sandy ecosystems Horqin Sandy Land
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Impact of Emerging Contaminants on Aquatic Ecosystems:A Mini-Review
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作者 El Mostapha Albou Asmae Nouayti +1 位作者 Ali El Mansour Ali Ait Boughrous 《Research in Ecology》 2025年第3期1-16,共16页
Emerging contaminants,such as pharmaceuticals,pesticides,microplastics,and per-and polyfluoroalkyl substances(PFAS),pose significant environmental and health risks due to their persistence,bioaccumulative nature,and e... Emerging contaminants,such as pharmaceuticals,pesticides,microplastics,and per-and polyfluoroalkyl substances(PFAS),pose significant environmental and health risks due to their persistence,bioaccumulative nature,and ecological toxicity.This mini-review examines their major sources,including industrial effluents,urban runoff,and landfill leachate,and highlights their detrimental impacts on aquatic biodiversity and human health.By synthesizing current research,the review emphasizes the urgent need for improved monitoring,regulatory interventions,and innovative mitigation strategies.It provides a concise overview to guide future research and inform policies aimed at safeguarding aquatic ecosystems and public health. 展开更多
关键词 Emerging Contaminants Aquatic ecosystems Water Pollution Water Management
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Micro-and nano-plastics:an emerging contaminant in marine and freshwater ecosystems
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作者 Minggang CAI Bin XIA +2 位作者 Wei HUANG Lei MAI Mengyang LIU 《Journal of Oceanology and Limnology》 2025年第2期343-345,共3页
Micro-and nano-plastics,defined as plastic particles measuring≤5 mm,represent a class of contaminants of emerging concern.These particles are ubiquitous in aquatic environments,posing significant threats to both fres... Micro-and nano-plastics,defined as plastic particles measuring≤5 mm,represent a class of contaminants of emerging concern.These particles are ubiquitous in aquatic environments,posing significant threats to both freshwater and marine organisms.The accumulation of micro-and nanoplastics in aquatic biota can lead to physical harm and chemical hazards,as these particles can serve as vectors for transporting toxic substances.As the research community strives to understand the transport and fate of micro-and nano-plastics,as well as their ecotoxicological implications,the scope of research questions continues to broaden.In response to these developments,the Journal of Oceanology and Limnology has recently launched a special issue entitled“Micro-and nano-plastics:an emerging contaminant in marine and freshwater ecosystems.” 展开更多
关键词 PLASTICS ecosystems TRANSPORT
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The complex impacts of fire on soil ecosystems:Insights from the 2021 Aspromonte National Park wildfire
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作者 Mariateresa Oliva Angela Maffia +4 位作者 Federica Marra Francesco Canino Santo Battaglia Carmelo Mallamaci Adele Muscolo 《Journal of Forestry Research》 2025年第5期113-124,共12页
Fires have historically played a natural role in shaping ecosystems,contributing to biodiversity and ecological renewal.However,in the Anthropocene,the interplay of climate change and human activities has exacerbated ... Fires have historically played a natural role in shaping ecosystems,contributing to biodiversity and ecological renewal.However,in the Anthropocene,the interplay of climate change and human activities has exacerbated fire frequency and intensity,with cascading impacts on soil health,biodiversity,and ecosystem resilience.This study highlights the complex effects of fire on soil ecosystems,particularly in Mediterranean environments,by analysing the aftermath of the 2021 wildfire in Aspromonte National Park.The results of this research reveal the multifaceted impact of fire on soil composition and biological activity.Burned areas exhibited altered microbial communities,characterized by a higher biomass of bacteria and actinomycetes but reduced fungal presence,aligning with findings that fungi are more sensitive to heat than other microorganisms,particularly under moist conditions.Changes in enzyme activity,such as decreased oxidoreductase and hydrolase activities but elevated catalase activity,suggest significant metabolic adjustments among surviving microbial strains.Additionally,increased potassium,magnesium,sulphates,and total phenols in burned areas point to shifts in nutrient dynamics driven by the combustion of organic matter.Fire also impacted microarthropod communities but the rapid recovery of microarthropod communities that has been recognized by numerous authors suggests that fire may not universally impair soil biodiversity in Mediterranean environments.The transition zone played a critical intermediate role,retaining a higher organic matter content than the unburned zone,suggesting its potential as a buffer or recovery zone in post-fire dynamics.Microarthropod communities,while initially affected,demonstrated resilience in line with previous research,indicating that Mediterranean soils might possess adaptive mechanisms to recover from low-to moderate-severity wildfires.Importantly,the incorporation of ashes and partially burned organic material in such fires may lead to enhanced soil fertility,fostering bacterial and actinomycetes proliferation and facilitating ecosystem recovery. 展开更多
关键词 Ecosystem resilience Mediterranean environment WILDFIRE Soil biodiversity Soil quality
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Vertical exchange versus horizontal dispersal in structuring local planktonic and sedimentary bacterial communities in polluted lotic ecosystems
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作者 Wei Zhang Wei Xiong +3 位作者 Min Wang Dongliang Zhao Xiaoyu Guo Aibin Zhan 《Journal of Environmental Sciences》 2025年第10期859-870,共12页
Elucidating the mechanisms underlying community assembly remains a central question in community ecology,especially in aquatic ecosystems disrupted by human activities.Understanding the causes and consequences of comm... Elucidating the mechanisms underlying community assembly remains a central question in community ecology,especially in aquatic ecosystems disrupted by human activities.Understanding the causes and consequences of community responses to changing environment is essential for revealing the ecological effects of anthropogenic disturbances and proposing practical strategies for ecological restoration.While stochastic dispersal and species sorting are known to influence local biological communities,most studies have focused on horizontal dispersal,often neglecting the vertical exchange of organisms between planktonic and sedimentary communities when studying stochastic dispersal.We used a highly disturbed urban river in Beijing as a model system to investigate the relative roles of stochastic dispersal versus species sorting driven by local pollution,as well as two components of stochastic dispersal,vertical exchange and horizontal dispersal,in structuring local bacterial communities.Our integrated analyses of planktonic and sedimentary bacterial communities revealed that,despite different spatial patterns along the river,both types of bacterial communities were primarily shaped by stochastic dispersal processes rather than species sorting influenced by the environmental gradient.Notably,in addition to the effect of horizontal dispersal along the river,the vertical exchange between planktonic and sedimentary bacterial communities significantly contributed to the formation of local communities.These findings suggest that both vertical exchange and horizontal dispersal should be considered when assessing the role of stochastic dispersal in shaping local community structure in microbial communities. 展开更多
关键词 Water pollution Vertical dispersal Species sorting Bacterial communities River management Urban ecosystem
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Dew Water as Sustainable Ecological Resource:Mitigating Heavy Metal Pollution in Aquatic Ecosystems and Enhancing Water Security
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作者 Jonny Jonny Pepita Zenia Fachira Rachel Agfata 《Research in Ecology》 2025年第4期292-305,共14页
Groundwater overextraction and contamination by heavy metals such as cadmium and arsenic have resultedin ecological degradation and increased risks of renal disease,particularly in water-scarce regions.To address thes... Groundwater overextraction and contamination by heavy metals such as cadmium and arsenic have resultedin ecological degradation and increased risks of renal disease,particularly in water-scarce regions.To address thesechallenges,this review aimed to evaluate the ecological potential of dew water harvesting as a sustainable and safealternative water source.Literature published between 2000 and 2024 was systematically searched in PubMed,Scopus,Web of Science,and Google Scholar using the terms“dew water,”“atmospheric water harvesting,”“groundwaterpollution,”“heavy metals,”“ecosystem restoration,”and“sustainable water systems.”Studies were included if theyfocused on dew water quality,ecological functions,or health-related outcomes,while non-English publications,conference abstracts without full text,and studies not directly addressing dew water were excluded.A total of 46 studiesand 7 official guidelines met the eligibility criteria.Findings indicate that natural dew water generally exhibits a neutralpH(6.5–8.5),negligible concentrations of heavy metals,and relatively high dissolved oxygen content(~9 mg/L).Casestudies from Morocco,Israel,China,and India illustrate its contributions to soil moisture retention,plant survival,biodiversity support,and microclimate regulation.Moreover,dew water produced through the Systemized Dew Process(SDP)consistently complied with WHO(2024)standards for drinking water,showing contaminant levels belowdetection thresholds.In conclusion,dew water harvesting represents a low-impact,climate-resilient,and safe alternativethat mitigates exposure to nephrotoxic pollutants,reduces reliance on overexploited groundwater,and enhances longtermecological restoration and water security in degraded and water-scarce environments. 展开更多
关键词 Ecological Sustainability Water Conservation Heavy Metal Pollution Ecosystem Restoration Climate Change Adaptation Renewable Water Sources Applied Ecology
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Response of carbon flux of alpine ecosystems to hydrological and meteorological factors on the Qinghai-Tibet Plateau
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作者 WANG Xiuying MA Yuancang +7 位作者 ZHOU Bingrong LI Fu SU Shulan DU Huali MA Honglu SUN Shujiao JI Haijuan ZHANG Rui 《Journal of Mountain Science》 2025年第8期2916-2935,共20页
Alpine meadows,alpine wetlands,and alpine desert steppes are the three typical vegetation types on the Qinghai-Tibet Plateau.The complex terrain and harsh climatic conditions across this region lead to considerable di... Alpine meadows,alpine wetlands,and alpine desert steppes are the three typical vegetation types on the Qinghai-Tibet Plateau.The complex terrain and harsh climatic conditions across this region lead to considerable diversification in the vegetation growth environment,resulting in substantial spatial heterogeneity in ecosystem carbon flux and its controlling mechanisms.Using eddy covariance data collected from March to August 2019,this study examined the responses of carbon and water fluxes in different ecosystems on the Tibetan Plateau to typical hydrometeorological factors,focusing on Net Ecosystem CO□Exchange(NEE)and Evapotranspiration(ET).The results indicate that:1)The Longbao alpine wetland primarily acted as a carbon sink from May to August,while serving as a carbon source from March to April.In the Maqin alpine meadow,it functioned as a carbon sink during June and July but acted as a carbon source in March,April,May,and August.The Tuotuohe alpine desert strppe was predominantly a net carbon sink from March to August.Overall,after the entire growing season(March to August),the Longbao alpine wetlands,Maqin alpine meadow,and Tuotuohe alpine desert steppe all showed net carbon sink properties,with net CO_(2)uptakes of 236.12 g/m^(2),291.45 g/m^(2),and 290.28 g/m^(2),respectively.2)The importance of meteorological factors to NEE varies with scale and ecosystem type,with global radiation(Rg)being the most critical factor influencing NEE variation.Volumetric soil water content(Soil_VWC)and soil temperature(Soil_T)had a positive effect on NEE at Maqin alpine meadow and Tuotuohe alpine desert steppe,while higher values of these variables showed a negative contribution.Furthermore,the sensitivity of NEE to Soil_T at Longbao alpine wetland and Tuotuohe alpine desert steppe was greater than its sensitivity to air temperature(Tair).3)The effect of Gross Primary Productivity(GPP)on NEE in alpine desert steppes is significantly greater than in alpine meadows.Both Ecosystem Respiration(Reco)and NEE were substantially limited by GPP,with 84%of GPP in alpine wetlands contributing to Reco and 16%to NEE;92%of GPP in alpine meadows contributing to Reco and 8%to NEE;and 40%of GPP in high-altitude desert grasslands contributing to Reco and 60%to NEE.4)The strong correlation between NEE and evapotranspiration suggests that water availability is the primary factor controlling changes in the carbon and water budgets of alpine ecosystems. 展开更多
关键词 Alpine wetland Alpine meadow Alpine desert steppe Eddy covariance Net ecosystem CO_(2)exchange(NEE)
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Increased soil organic carbon storage in Chinese terrestrial ecosystems from the 1980s to the 2010s 被引量:54
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作者 XU Li YU Guirui HE Nianpeng 《Journal of Geographical Sciences》 SCIE CSCD 2019年第1期49-66,共18页
Soil stores a large amount of the terrestrial ecosystem carbon (C) and plays an important role in maintaining global C balance. However, very few studies have addressed the regional patterns of soil organic carbon (SO... Soil stores a large amount of the terrestrial ecosystem carbon (C) and plays an important role in maintaining global C balance. However, very few studies have addressed the regional patterns of soil organic carbon (SOC) storage and the main factors influencing its changes in Chinese terrestrial ecosystems, especially using field measured data. In this study, we collected information on SOC storage in main types of ecosystems (including forest, grassland, cropland, and wetland) across 18 regions in China during the 1980s (from the Second National Soil Survey of China, SNSSC) and the 2010s (from studies published between 2004 and 2014), and evaluated its changing trends during these 30 years. The SOC storage (0-100 cm) in Chinese terrestrial ecosystems was 83.46 ± 11.89 Pg C in the 1980s and 86.50 ± 8.71 Pg C in the 2010s, and the net increase over the 30 years was 3.04 ± 1.65 Pg C, with an overall rate of 0.101 ± 0.055 Pg C yr<sup>-1</sup>. This increase was mainly observed in the topsoil (0-20 cm). Forests, grasslands, and croplands SOC storage increased 2.52 ± 0.77, 0.40 ± 0.78, and 0.07 ± 0.31 Pg C, respectively, which can be attributed to the several ecological restoration projects and agricultural practices implemented. On the other hand, SOC storage in wetlands declined 0.76 ± 0.29 Pg C, most likely because of the decrease of wetland area and SOC density. Combining these results with those of vegetation C sink (0.100 Pg C yr<sup>-1</sup>), the net C sink in Chinese terrestrial ecosystems was about 0.201 ± 0.061 Pg C yr<sup>-1</sup>, which can offset 14.85%-27.79% of the fossil fuel C emissions from the 1980s to the 2010s. These first estimates of soil C sink based on field measured data supported the premise that China’s terrestrial ecosystems have a large C sequestration potential, and further emphasized the importance of forest protection and reforestation to increase SOC storage capacity. 展开更多
关键词 CHINESE TERRESTRIAL ecosystems CHANGE storage soil ORGANIC carbon
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Microclimate and Its Formation Mechanism in Cunninghamia lanceolata Hook. Plantation Ecosystems in the Subtropical Zone of China 被引量:2
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作者 张合平 田大伦 +1 位作者 康文星 艾顺儒 《Forestry Studies in China》 CAS 2001年第2期26-31,共6页
Microclimate characteristics and related environmental energy mechanisms were examined based on the long term located observations in the mature, thinned and young Cunninghamia lanceolata plantation ecosystems in... Microclimate characteristics and related environmental energy mechanisms were examined based on the long term located observations in the mature, thinned and young Cunninghamia lanceolata plantation ecosystems in western Hunan Province, China. The results show that the mature plantation ecosystem can improve the microclimate significantly by regulating the amount and spatial distribution of environmental energy, which delineates the pattern of the microclimate in forest ecosystems in the process of ecological restoration. Compared with the young plantation, the mature plantation ecosystem decreased annual mean air temperature by 0 4℃. The maximum decrease in monthly mean air temperature was 2 3℃. The mature plantation ecosystem decreased annual mean ground temperature by 1 2℃ with a maximum decrease in monthly mean ground temperature of 2 3℃. Mainly due to the dense canopy, the mature forest ecosystem regulates the distribution of radiation energy, and expenditure ratios of heat budget and principal energy components to decrease temperature or make it even. 展开更多
关键词 Cunninghamia lanceolata plantation ecosystem MICROCLIMATE environmental energy
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Nitrate in shallow groundwater in typical agricultural and forest ecosystems in China,2004-2010 被引量:12
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作者 Xinyu Zhang Zhiwei Xu +2 位作者 Xiaomin Sun Wenyi Dong Deborah Ballantine 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第5期1007-1014,共8页
The nitrate-nitrogen(NO 3-N) concentrations from shallow groundwater wells situated in 29 of the Chinese Ecosystem Research Network field stations,representing typical agroand forest ecosystems,were assessed using m... The nitrate-nitrogen(NO 3-N) concentrations from shallow groundwater wells situated in 29 of the Chinese Ecosystem Research Network field stations,representing typical agroand forest ecosystems,were assessed using monitoring data collected between 2004 and 2010.Results from this assessment permit a national scale assessment of nitrate concentrations in shallow groundwater,and allow linkages between nitrate concentrations in groundwater and broad land use categories to be made.Results indicated that most of the NO 3--N concentrations in groundwater from the agroand forest ecosystems were below the Class 3 drinking water standard stated in the Chinese National Standard:Quality Standard for Ground Water(≤ 20 mg/L).Over the study period,the average NO 3--N concentrations were significantly higher in agro-ecosystems(4.1 ± 0.33 mg/L) than in forest ecosystems(0.5 ± 0.04 mg/L).NO 3-N concentrations were relatively higher(〉 10 mg N /L) in 10 of the 43 wells sampled in the agricultural ecosystems.These elevated concentrations occurred mainly in the Ansai,Yucheng,Linze,Fukang,Akesu,and Cele field sites,which were located in arid and semiarid areas where irrigation rates are high.We suggest that improvements in N fertilizer application and irrigation management practices in the arid and semi-arid agricultural ecosystems of China are the key to managing groundwater nitrate concentrations. 展开更多
关键词 Chinese Ecosystem Research Network shallow groundwater AGRICULTURAL forest ecosystems nitrate concentration
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Mitigation Options for Methane, Nitrous Oxide and NitricOxide Emissions from Agricultural Ecosystems 被引量:14
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作者 郑循华 王明星 +7 位作者 王跃思 沈壬兴 李晶 J.Heyer M.Koegge H.Papen 金继生 李老土 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2000年第1期83-92,共10页
An experimental study on mitigation of greenhouse gas (CH4, N2O and NO) emission has been conducted in a typical cropping system of Southeast China for 4 years. By simultaneous measurement, the CH4, N2O and NO emissio... An experimental study on mitigation of greenhouse gas (CH4, N2O and NO) emission has been conducted in a typical cropping system of Southeast China for 4 years. By simultaneous measurement, the CH4, N2O and NO emission fluxes from rice-wheat rotation fields, effects of fertilization, water management, temperature and soil moisture were investigated. Temperature, fertilization and water status were found to be the key factors to regulate CH4, N2O and NO emis-sions. Based on the experimental results, some agricultural measures were recommended as techni-cal options to mitigate greenhouse gas emissions from rice-wheat rotation ecosystems. These miti-gation measures are reducing mineral N input, coupling organic manure with chemical fertilizers, applying fertilizers which release available N slowly during periods with intensive plant activity, and applying dry fermented organic manure and well management of water and fertilizer. Key words Mitigation options - Emission - Greenhouse gases - Ecosystems This study was supported by projects “ Experimental and Modeling Study on N2O Emission from the Rice-Wheat Rotation Fields of Southeast China” and “ Experimental and Modeling Study on NO Emission from Croplands” , which were granted by the National Natural Science Foundation of China, the State Key Fundamental Research Project “ Predicting the Future (20–50 years) Trend of Environmental Change in China”, and the project of Chinese Academy of Sciences “ Theory and Methodology on Air Pollution Prediction”.Thanks are due to Professor Zhang Wen, Dr. Bai Jianhui, Mr. Gong Yanbang, Mrs. Luo Dongmei and Mr. Liu Guangren from the Institute of Atmospheric Physics, Chinese Academy of Sciences for their help in experiments. 展开更多
关键词 Mitigation options Emission Greenhouse gases ecosystems
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Prevalence and Phylogenetic Analysis of Crimean-Congo Hemorrhagic Fever Virus in Ticks from Different Ecosystems in Xinjiang,China 被引量:9
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作者 Abulimiti Moming Xihong Yue +9 位作者 Shu Shen Chenchen Chang Cheng Wang Tao Luo Yanfang Zhang Rong Guo Zhihong Hu Yujiang Zhang Fei Deng Surong Sun 《Virologica Sinica》 SCIE CAS CSCD 2018年第1期67-73,共7页
The Crimean-Congo hemorrhagic fever virus(CCHFV),a member of the genus Orthonairovirus and family Nairoviridae,is transmitted by ticks and causes severe hemorrhagic disease in humans.To study the epidemiology of CCHFV... The Crimean-Congo hemorrhagic fever virus(CCHFV),a member of the genus Orthonairovirus and family Nairoviridae,is transmitted by ticks and causes severe hemorrhagic disease in humans.To study the epidemiology of CCHFV in different ecosystems in Xinjiang,China,a total of 58,932 ticks were collected from Tarim Basin,Junggar Basin,Tianshan Mountain,and Altai Mountain from 2014 to 2017.Hyalomma asiaticum asiaticum was the dominant tick species in Tarim and Junggar basins,whereas Dermacentor nuttalli and Hyalomma detritum were found in Tianshan Mountain and Altai Mountain,respectively.Reverse transcription-polymerase chain reaction of the CCHFV small(S)genome segment was used for the molecular detection.The CCHFV-positive percentage was 5.26%,6.85%,1.94%,and 5.56% in Tarim Basin,Junggar Basin,Tianshan Mountain,and Altai Mountain,respectively.Sequences of the S segment were used for phylogenetic analysis and the results showed that the newly identified CCHFV strains belonged to two clades.Our study confirms that H.asiaticum asiaticum is the major vector of CCHFV in desert habitats which is consistent with previous studies,and also suggests that H.detritum and D.nuttalli are emerging vectors for CCHFV in Xinjiang.Moreover,this study reports the presence of CCHFV in the mountain habitat of Xinjiang for the first time,suggesting that future surveillance of CCHFV should also include mountainous areas. 展开更多
关键词 Crimean-Congo hemorrhagic fever virus (CCHFV) PREVALENCE Homology TICK ecosystems XINJIANG
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A review of ecological impacts of global climate change on persistent organic pollutant and mercury pathways and exposures in arctic marine ecosystems 被引量:7
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作者 Melissa A. MCKINNEY Sara PEDRO +5 位作者 Rune DIETZ Christian SONNE Aaron T. FISK Denis ROY Bjorn M. JENSSEN Robert J. LETCHER 《Current Zoology》 SCIE CAS CSCD 2015年第4期617-628,共12页
Bioaccumulative and biomagnifying contaminants, such as persistent organic pollutants (POPs) and mercury (Hg), have for decades been recognized as a health concern in arctic marine biota. In recent years, global c... Bioaccumulative and biomagnifying contaminants, such as persistent organic pollutants (POPs) and mercury (Hg), have for decades been recognized as a health concern in arctic marine biota. In recent years, global climate change (GCC) and related loss of arctic sea ice have been observed to be driving substantial change in arctic ecosystems. This review summarizes findings documenting empirical links between GCC-induced ecological changes and alterations in POP and Hg exposures and pathways in arctic marine ecosystems. Most of the studies have reported changes in POP or Hg concentrations in tissue in relation to GCC-induced changes in species trophic interactions. These studies have typically focused on the role of changes in abun- dance, habitat range or accessibility of prey species, particularly in relation to sea ice changes. Yet, the ecological change that re- suited in contaminant trend changes has often been unclear or assumed. Other studies have successfully used chemical tracers, such as stable nitrogen and carbon isotope ratios and fatty acid signatures to link such ecological changes to contaminant level variations or trends. Lower sea ice linked-diet changes/variation were associated with higher contaminant levels in some popula- tions of polar bears, ringed seals, and thick-billed murres, but the influence of changing trophic interactions on POP levels and trends varied widely in both magnitude and direction. We suggest that future research in this new area of GCC-linked ecotox- icology should focus on routine analysis of ancillary ecological metrics with POP and Hg studies, simultaneous consideration of the multiple mechanisms by which GCC and contaminant interactions can occur, and targeted research on changing exposures and toxicological effects in species known to be sensitive to both GCC and contaminants [Current Zoology 61 (4): 617-628, 2015]. 展开更多
关键词 Climate change Ecological change CONTAMINANTS TRENDS ARCTIC Marine ecosystems
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Differentiation of Soil Fauna Populations in Conventional Tillage and No-Tillage Red Soil Ecosystems 被引量:8
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作者 HU FENG LI HUIXIN and WU SHANMEI(Nanjing Agriculturol University, Nanjing 210095 (China)) 《Pedosphere》 SCIE CAS CSCD 1997年第4期339-348,共10页
In a field experiment, the populations of major soil fauna groups including earthworms, enchytraeids,arthropods and nematodes were examined in conventional tillage (CT) and no-tillage (NT) red soil ecosystems to evalu... In a field experiment, the populations of major soil fauna groups including earthworms, enchytraeids,arthropods and nematodes were examined in conventional tillage (CT) and no-tillage (NT) red soil ecosystems to evaluate their responses to tillage disturbance. Earthworms, macrry and micro-arthropods were stimulated under NT with earthworms showing the highest population increase by four times, while enchytraeids and nematodes favored CT system, predicting certain adaptability of these animals to plow-disturbed soil environment. On the basis of relative response index it was found that soil fauna was more sensitive to tillage than soil resource base (C and N pools) and microflora. The population structure of soil fauna was also affected by tillage treatments. Analysis on nematode trophic groups showed that bacteria-feeding and plant parasitic nematodes were more abundant in CT soil whereas the proportions of fungivores and omnivorepredators increased in NT soil. Possible reasons for the differentiation in both size and structure of the fauna population were discussed and the ecological significance involved in these changes was emphasized. 展开更多
关键词 conventional tillage NO-TILLAGE red soil ecosystems soil fauna
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