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
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
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
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
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
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
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
Land use change and occupation have led to modifications in the environment causing loss of biodiversity and ecosystem services throughout the planet.Some environments with high economic relevance,such as the ferrugin...Land use change and occupation have led to modifications in the environment causing loss of biodiversity and ecosystem services throughout the planet.Some environments with high economic relevance,such as the ferruginous campo rupestre(rupestrian grassland known as Canga in Brazil),are even more susceptible to severe impacts due to their extreme habitat conditions and low resilience.The determination of reference ecosystems based on the intrinsic characteristics of the ecosystem is essential for conservation as well as to the implementation of ecological restoration.We proposed the reference ecosystem of the three main types of habitats of the ferruginous campo rupestre based on their floristic composition.We described the floristic composition of each habitat and evaluated the physicochemical properties of the soils and the relationship between plants and soils.All three habitats showed high diversity of plant species and many endemic species,such as Chamaecrista choriophylla,Cuphea pseudovaccinium,Lychnophora pinaster,and Vellozia subalata.The distribution of vegetation was strongly related with the edaphic characteristics,with a set of species more adapted to high concentration of base saturation,fine sand,organic carbon,and iron,while another set of species succeeded in more acidic soils with higher S and silt concentration.We provide support for the contention that the ferruginous campo rupestre is a mosaic of different habitats shaped by intrinsic local conditions.Failure to recognize the floristic composition of each particular habitat can lead to inappropriate restoration,increased habitat homogenization and increased loss of biodiversity and ecosystem services.This study also advances the knowledge base for building the reference ecosystem for the different types of ferruginous campo rupestre habitats,as well as a key database for highlighting those species contribute most to community assembly in this diverse and threatened tropical mountain ecosystem.展开更多
Embracing software product lines(SPLs)is pivotal in the dynamic landscape of contemporary software devel-opment.However,the flexibility and global distribution inherent in modern systems pose significant challenges to...Embracing software product lines(SPLs)is pivotal in the dynamic landscape of contemporary software devel-opment.However,the flexibility and global distribution inherent in modern systems pose significant challenges to managing SPL variability,underscoring the critical importance of robust cybersecurity measures.This paper advocates for leveraging machine learning(ML)to address variability management issues and fortify the security of SPL.In the context of the broader special issue theme on innovative cybersecurity approaches,our proposed ML-based framework offers an interdisciplinary perspective,blending insights from computing,social sciences,and business.Specifically,it employs ML for demand analysis,dynamic feature extraction,and enhanced feature selection in distributed settings,contributing to cyber-resilient ecosystems.Our experiments demonstrate the framework’s superiority,emphasizing its potential to boost productivity and security in SPLs.As digital threats evolve,this research catalyzes interdisciplinary collaborations,aligning with the special issue’s goal of breaking down academic barriers to strengthen digital ecosystems against sophisticated attacks while upholding ethics,privacy,and human values.展开更多
Methane (CH_(4)), a potent greenhouse gas, plays a pivotal role in the dynamics of climate change. While CH_(4) emissions have been widely investigated,biological removal of CH_(4) by upland soils has been less explor...Methane (CH_(4)), a potent greenhouse gas, plays a pivotal role in the dynamics of climate change. While CH_(4) emissions have been widely investigated,biological removal of CH_(4) by upland soils has been less explored. Understanding the mechanisms and factors affecting CH_(4) oxidation in soils is of paramount importance for devising successful mitigation strategies. This perspective paper discusses different types of aerobic methanotrophs and their activities under varying environmental conditions, highlighting the significant contribution of soil ecosystems to global CH_(4) sinks. We emphasize the need for in-depth research on variables controlling CH_(4) sinks on different spatiotemporal scales and the exploration of previously unidentified CH_(4) sinks, such as deserts and areas of glacier retreat.展开更多
Groundwater-Dependent Ecosystems(GDEs)in the arid region of northwest China are crucial for maintaining ecological balance and biodiversity.However,the ongoing decline in groundwater levels caused by excessive groundw...Groundwater-Dependent Ecosystems(GDEs)in the arid region of northwest China are crucial for maintaining ecological balance and biodiversity.However,the ongoing decline in groundwater levels caused by excessive groundwater exploitation poses a potential threat to GDEs.This paper reviews the current developments and future challenges associated with defining groundwater level thresholds for maintaining GDEs in arid regions.It focuses on methods for identifying and investigating these thresholds,with particular attention to recent advances in northwest China.Additionally,this paper highlights the limitations and future challenges in determining these thresholds,including the complexities of ecological processes,groundwater systems,data availability,and methodological constraints.To address these issues,a multidisciplinary approach that incorporates new technologies,such as multi-source data fusion,machine learning models,and big data and cloud computing,will be essential.By overcoming these challenges and utilizing effective methods,appropriate groundwater level thresholds can be established to ensure the longterm sustainability of GDEs.展开更多
River ecosystems face challenges due to environmental degradation and alterations in flow and sediment transport resulting from climate change and other anthropogenic impacts.These changes may substantially affect riv...River ecosystems face challenges due to environmental degradation and alterations in flow and sediment transport resulting from climate change and other anthropogenic impacts.These changes may substantially affect river morphology,nutrient dynamics,wetland vegetation,aquatic habitats,and river ecological stability.This highlights the urgent need for systematic and quantitative studies on the interactions and feedback between changes in flow,sediment transport,and river ecology.In this study,we reviewed flow and sediment transport changes in major Chinese rivers,along with their resulting ecological impacts.We propose conducting eco-fluvial dynamic studies,a potential solution that can guide the evaluation and restoration of ecological health impacted by physical processes.These studies can provide major benefits in balancing human and environmental needs in large river systems,which is crucial for the healthy and sustainable development of rivers.展开更多
As global urbanization accelerates,urban ecosystems are facing unprecedented challenges.In the past,humans have seen themselves as masters of the universe,controlling natural resources through large-scale urbanization...As global urbanization accelerates,urban ecosystems are facing unprecedented challenges.In the past,humans have seen themselves as masters of the universe,controlling natural resources through large-scale urbanization.However,with a deeper understanding of ecosystems,people are realizing that they are only one part of the ecosystem,and that the health of urban ecosystems is directly related to the well-being and future of humanity.展开更多
Quantitative assessment of organic carbon(OC)stocks in different habitats is crucial in ecology.Understanding the drivers affecting OC stocks across distinct carbon pools is essential for comprehending current pattern...Quantitative assessment of organic carbon(OC)stocks in different habitats is crucial in ecology.Understanding the drivers affecting OC stocks across distinct carbon pools is essential for comprehending current patterns and predicting future changes.Alpine ecosystems,important for atmospheric CO_(2)regulation and highly vulnerable to climate change,are priority study areas.This research aims to estimate OC stocks in different pools(soil,organic horizons,and aboveground vegetation)and identify factors influencing these stocks in an alpine environment.We sampled 146 sites representing six forest types and two grassland types in the Gran Paradiso National Park(northern Italian Alps).Field samples of soils,organic horizons,and data on aboveground trees were collected to assess OC stocks,along with environmental variables.Our findings reveal nuanced variations in OC stocks across different ecosystem components.In grasslands,average soil OC was 5.57 kg m^(-2),while in forests it was 4.11 kg m^(-2).Organic horizons contained an average of 0.70 kg m^(-2),and aboveground vegetation in forests stored 6.61 kg m^(-2).Linear Mixed Models indicate that soil OC is influenced by habitat type,soil type,and elevation.OC in organic horizons is affected by aspect and forest habitat type,with composting further influenced by elevation.These results contribute to OC stock inventories for alpine ecosystems and enhance our understanding of how environmental factors influence carbon storage.Importantly,they underscore the need to consider soil type and other factors beyond land use when modeling OC stocks.This insight has implications for designing effective territorial strategies to address climate change,emphasizing the importance of a multifaceted approach to carbon stock assessment and management in alpine regions.展开更多
Traditional river health assessment relies on limited water quality indices and representative organism activity,but does not comprehensively obtain biotic and abiotic information of the ecosystem.Here,we propose a ne...Traditional river health assessment relies on limited water quality indices and representative organism activity,but does not comprehensively obtain biotic and abiotic information of the ecosystem.Here,we propose a new approach to evaluate the ecological and health risks of river aquatic ecosystems.First,detailed physicochemical and biological characterization of a river ecosystem can be obtained through pollutant determination(especially emerging pollutants)and DNA/RNA sequencing.Second,supervised machine learning can be applied to perform classification analysis of characterization data and ascertain river ecosystem ecology and health.Our proposed methodology transforms river ecosystem health assessment and can be applied in river management.展开更多
The question of the impact of war on ecosystems still remains secondary in the internal and external policy of states, society and the agenda of international organizations. From the point of view of losses in monetar...The question of the impact of war on ecosystems still remains secondary in the internal and external policy of states, society and the agenda of international organizations. From the point of view of losses in monetary terms, the values of ecosystem damages obtained in the work, which are a consequence of the impact of hostilities on the environment, correspond to the annual budgets of the largest countries in the world or exceed them. The presented calculations significantly exceed the known normative methods, the use of which in the conditions of war is limited in space and time. Objective difficulties associated with the uncertainty of many processes of the development of ecological systems and their reaction to the multifactorial impact of war are also significant limitations. Therefore, as part of the study, a method of assessing the impact of war on the environment is proposed, which is based on the patterns of energy flows in ecosystems from the moment it is binding by producers. This made it possible to take into account in the calculations the principle of functional integrity of the ecological system, according to which the destruction or damage of the components of a functionally whole environment will necessarily cause negative phenomena in the development of ecological systems. The results are presented in the form of real values of ecological losses in energy and monetary equivalents, as consequences of the loss of ecosystem services. As the results of the research show, the minimum amount of damage to ecosystems from Russian tanks is 43,500 USD per day. Environmental damage from Russian fighter jets has been estimated at $1.5 billion per week since the start of the war. Noise from military operations causes losses of at least 2.3 billion US dollars per year. The obtained results create prerequisites for improving the system of ensuring environmental safety at the local, state, and international levels and transferring the obtained solutions into safety-shaping practice.展开更多
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
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
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
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
基金supported by the National Grassland Technology Innovation Centre(Preparation)Project(CCPTZX2023B02-2)the National Natural Science Foundation of China(32071845)the Key Science and Technology Project of Inner Mongolia Autonomous Region(2021ZD001505).
文摘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.
文摘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.
基金Supported by the Natural Science Key Foundation of Fujian Province,China(No.2020J02002)the Hainan Province Science and Technology Special Fund(No.ZDYF2022SHFZ317)。
文摘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.”
基金funding provided by Universitàdegli Studi Mediterranea di Reggio Calabria within the CRUI-CARE Agreementfunded by Calabrian Region,grant number DDL n°16315657 del 13-12-2022,POR CALABRIA FESR-FSE 2014-2020 ASSE I-PROMOZIONE DELLA RICERCA 658 E DELL’INNOVAZIONE.
文摘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.
基金supported by the National Natural Science Foundation of China(No.32471608)the Open Project of Key Laboratory of Environmental Biotechnology,CAS(No.kf2020002)Yunnan Collaborative Innovation Center for Plateau Lake Ecology and Environmental Health.
文摘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.
基金supported in part by the Fundamental Research Project of the Science and Technology Department of the Qinghai Province(Grant No.2025-ZJ-739)the National Natural Science Foundation of China(Grant No.U21A2021)+1 种基金the Open Fund of Greenhouse Gas and Carbon Neutral Key Laboratory of Qinghai Province(Grant No.ZDXM-2023-3)the Key Projects of Qinghai Meteorological Bureau(Grant No.QXZD2024-08)。
文摘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.
基金National Key R&D Program of China,No.2018YFD1100101。
文摘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.
基金Anglo American and Knowledge Center for Biodiversity for financial supportthe research funding agencies CNPq(Conselho Nacional de Desenvolvimento Científico e Tecnológico)+2 种基金scholarship from CNPq(151341/2023-0,150001/2023-1)FAPEMIG(Fundação de AmparoàPesquisa do Estado de Minas Gerais)Peld-CRSC 17(Long Term Ecology Program-campo rupestre of Serra do Cipó)。
文摘Land use change and occupation have led to modifications in the environment causing loss of biodiversity and ecosystem services throughout the planet.Some environments with high economic relevance,such as the ferruginous campo rupestre(rupestrian grassland known as Canga in Brazil),are even more susceptible to severe impacts due to their extreme habitat conditions and low resilience.The determination of reference ecosystems based on the intrinsic characteristics of the ecosystem is essential for conservation as well as to the implementation of ecological restoration.We proposed the reference ecosystem of the three main types of habitats of the ferruginous campo rupestre based on their floristic composition.We described the floristic composition of each habitat and evaluated the physicochemical properties of the soils and the relationship between plants and soils.All three habitats showed high diversity of plant species and many endemic species,such as Chamaecrista choriophylla,Cuphea pseudovaccinium,Lychnophora pinaster,and Vellozia subalata.The distribution of vegetation was strongly related with the edaphic characteristics,with a set of species more adapted to high concentration of base saturation,fine sand,organic carbon,and iron,while another set of species succeeded in more acidic soils with higher S and silt concentration.We provide support for the contention that the ferruginous campo rupestre is a mosaic of different habitats shaped by intrinsic local conditions.Failure to recognize the floristic composition of each particular habitat can lead to inappropriate restoration,increased habitat homogenization and increased loss of biodiversity and ecosystem services.This study also advances the knowledge base for building the reference ecosystem for the different types of ferruginous campo rupestre habitats,as well as a key database for highlighting those species contribute most to community assembly in this diverse and threatened tropical mountain ecosystem.
基金supported via funding from Ministry of Defense,Government of Pakistan under Project Number AHQ/95013/6/4/8/NASTP(ACP).Titled:Development of ICT and Artificial Intelligence Based Precision Agriculture Systems Utilizing Dual-Use Aerospace Technologies-GREENAI.
文摘Embracing software product lines(SPLs)is pivotal in the dynamic landscape of contemporary software devel-opment.However,the flexibility and global distribution inherent in modern systems pose significant challenges to managing SPL variability,underscoring the critical importance of robust cybersecurity measures.This paper advocates for leveraging machine learning(ML)to address variability management issues and fortify the security of SPL.In the context of the broader special issue theme on innovative cybersecurity approaches,our proposed ML-based framework offers an interdisciplinary perspective,blending insights from computing,social sciences,and business.Specifically,it employs ML for demand analysis,dynamic feature extraction,and enhanced feature selection in distributed settings,contributing to cyber-resilient ecosystems.Our experiments demonstrate the framework’s superiority,emphasizing its potential to boost productivity and security in SPLs.As digital threats evolve,this research catalyzes interdisciplinary collaborations,aligning with the special issue’s goal of breaking down academic barriers to strengthen digital ecosystems against sophisticated attacks while upholding ethics,privacy,and human values.
基金support from the Ministry of Environment of Korea(Nos.2022003640002 and RS-202300232066)。
文摘Methane (CH_(4)), a potent greenhouse gas, plays a pivotal role in the dynamics of climate change. While CH_(4) emissions have been widely investigated,biological removal of CH_(4) by upland soils has been less explored. Understanding the mechanisms and factors affecting CH_(4) oxidation in soils is of paramount importance for devising successful mitigation strategies. This perspective paper discusses different types of aerobic methanotrophs and their activities under varying environmental conditions, highlighting the significant contribution of soil ecosystems to global CH_(4) sinks. We emphasize the need for in-depth research on variables controlling CH_(4) sinks on different spatiotemporal scales and the exploration of previously unidentified CH_(4) sinks, such as deserts and areas of glacier retreat.
基金financially supported by the China Geological Survey Project(No.DD20230472).
文摘Groundwater-Dependent Ecosystems(GDEs)in the arid region of northwest China are crucial for maintaining ecological balance and biodiversity.However,the ongoing decline in groundwater levels caused by excessive groundwater exploitation poses a potential threat to GDEs.This paper reviews the current developments and future challenges associated with defining groundwater level thresholds for maintaining GDEs in arid regions.It focuses on methods for identifying and investigating these thresholds,with particular attention to recent advances in northwest China.Additionally,this paper highlights the limitations and future challenges in determining these thresholds,including the complexities of ecological processes,groundwater systems,data availability,and methodological constraints.To address these issues,a multidisciplinary approach that incorporates new technologies,such as multi-source data fusion,machine learning models,and big data and cloud computing,will be essential.By overcoming these challenges and utilizing effective methods,appropriate groundwater level thresholds can be established to ensure the longterm sustainability of GDEs.
基金National Key Research and Development Program of China,Grant/Award Number:2022YFC3201803National Natural Science Foundation of China,Grant/Award Numbers:12272209,U2040214。
文摘River ecosystems face challenges due to environmental degradation and alterations in flow and sediment transport resulting from climate change and other anthropogenic impacts.These changes may substantially affect river morphology,nutrient dynamics,wetland vegetation,aquatic habitats,and river ecological stability.This highlights the urgent need for systematic and quantitative studies on the interactions and feedback between changes in flow,sediment transport,and river ecology.In this study,we reviewed flow and sediment transport changes in major Chinese rivers,along with their resulting ecological impacts.We propose conducting eco-fluvial dynamic studies,a potential solution that can guide the evaluation and restoration of ecological health impacted by physical processes.These studies can provide major benefits in balancing human and environmental needs in large river systems,which is crucial for the healthy and sustainable development of rivers.
文摘As global urbanization accelerates,urban ecosystems are facing unprecedented challenges.In the past,humans have seen themselves as masters of the universe,controlling natural resources through large-scale urbanization.However,with a deeper understanding of ecosystems,people are realizing that they are only one part of the ecosystem,and that the health of urban ecosystems is directly related to the well-being and future of humanity.
文摘Quantitative assessment of organic carbon(OC)stocks in different habitats is crucial in ecology.Understanding the drivers affecting OC stocks across distinct carbon pools is essential for comprehending current patterns and predicting future changes.Alpine ecosystems,important for atmospheric CO_(2)regulation and highly vulnerable to climate change,are priority study areas.This research aims to estimate OC stocks in different pools(soil,organic horizons,and aboveground vegetation)and identify factors influencing these stocks in an alpine environment.We sampled 146 sites representing six forest types and two grassland types in the Gran Paradiso National Park(northern Italian Alps).Field samples of soils,organic horizons,and data on aboveground trees were collected to assess OC stocks,along with environmental variables.Our findings reveal nuanced variations in OC stocks across different ecosystem components.In grasslands,average soil OC was 5.57 kg m^(-2),while in forests it was 4.11 kg m^(-2).Organic horizons contained an average of 0.70 kg m^(-2),and aboveground vegetation in forests stored 6.61 kg m^(-2).Linear Mixed Models indicate that soil OC is influenced by habitat type,soil type,and elevation.OC in organic horizons is affected by aspect and forest habitat type,with composting further influenced by elevation.These results contribute to OC stock inventories for alpine ecosystems and enhance our understanding of how environmental factors influence carbon storage.Importantly,they underscore the need to consider soil type and other factors beyond land use when modeling OC stocks.This insight has implications for designing effective territorial strategies to address climate change,emphasizing the importance of a multifaceted approach to carbon stock assessment and management in alpine regions.
基金supported by the NationalNatural Science Foundation of China (No.52293442)the Special Fund from the State Key Joint Laboratory of Environment Simulation and Pollution Control (No.22Z01ESPCR)。
文摘Traditional river health assessment relies on limited water quality indices and representative organism activity,but does not comprehensively obtain biotic and abiotic information of the ecosystem.Here,we propose a new approach to evaluate the ecological and health risks of river aquatic ecosystems.First,detailed physicochemical and biological characterization of a river ecosystem can be obtained through pollutant determination(especially emerging pollutants)and DNA/RNA sequencing.Second,supervised machine learning can be applied to perform classification analysis of characterization data and ascertain river ecosystem ecology and health.Our proposed methodology transforms river ecosystem health assessment and can be applied in river management.
文摘The question of the impact of war on ecosystems still remains secondary in the internal and external policy of states, society and the agenda of international organizations. From the point of view of losses in monetary terms, the values of ecosystem damages obtained in the work, which are a consequence of the impact of hostilities on the environment, correspond to the annual budgets of the largest countries in the world or exceed them. The presented calculations significantly exceed the known normative methods, the use of which in the conditions of war is limited in space and time. Objective difficulties associated with the uncertainty of many processes of the development of ecological systems and their reaction to the multifactorial impact of war are also significant limitations. Therefore, as part of the study, a method of assessing the impact of war on the environment is proposed, which is based on the patterns of energy flows in ecosystems from the moment it is binding by producers. This made it possible to take into account in the calculations the principle of functional integrity of the ecological system, according to which the destruction or damage of the components of a functionally whole environment will necessarily cause negative phenomena in the development of ecological systems. The results are presented in the form of real values of ecological losses in energy and monetary equivalents, as consequences of the loss of ecosystem services. As the results of the research show, the minimum amount of damage to ecosystems from Russian tanks is 43,500 USD per day. Environmental damage from Russian fighter jets has been estimated at $1.5 billion per week since the start of the war. Noise from military operations causes losses of at least 2.3 billion US dollars per year. The obtained results create prerequisites for improving the system of ensuring environmental safety at the local, state, and international levels and transferring the obtained solutions into safety-shaping practice.
基金The Chinese Academy of Sciences Strategic Priority Research Program,No.XDA19020302National Key Research Project of China,No.2016YFC0500202National Natural Science Foundation of China,No.31290221,No.41571130043,No.31570471
文摘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.
文摘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.
基金supported by the Key Direction in Knowledge Innovation Program of Chinese Academy of Sciences (No. KZCX2-EW-310)the National Natural Science Foundation of China (No. 41171153)
文摘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.
文摘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.
