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Most probable transition paths in eutrophicated lake ecosystem under Gaussian white noise and periodic force
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作者 姜金连 徐伟 +1 位作者 韩平 牛立志 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第6期155-162,共8页
The effects of stochastic perturbations and periodic excitations on the eutrophicated lake ecosystem are explored.Unlike the existing work in detecting early warning signals,this paper presents the most probable trans... The effects of stochastic perturbations and periodic excitations on the eutrophicated lake ecosystem are explored.Unlike the existing work in detecting early warning signals,this paper presents the most probable transition paths to characterize the regime shifts.The most probable transition paths are obtained by minimizing the Freidlin-Wentzell(FW)action functional and Onsager-Machlup(OM)action functional,respectively.The most probable path shows the movement trend of the lake eutrophication system under noise excitation,and describes the global transition behavior of the system.Under the excitation of Gaussian noise,the results show that the stability of the eutrophic state and the oligotrophic state has different results from two perspectives of potential well and the most probable transition paths.Under the excitation of Gaussian white noise and periodic force,we find that the transition occurs near the nearest distance between the stable periodic solution and the unstable periodic solution. 展开更多
关键词 eutrophicated lake ecosystem Freidlin-Wentzell action functional Onsager-Machlup action functional most probable transition path
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DONGHU LAKE ECOSYSTEM EXPERIMENTAL STATION
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《Bulletin of the Chinese Academy of Sciences》 1999年第4期253-253,共1页
Location & environmental features: Donghu Lake is located at 114°23′ E and 30°33′N in the eastern suburbs of the city of Wuhan, capital of Hubei Province in central China. It is a typical shallow-botto... Location & environmental features: Donghu Lake is located at 114°23′ E and 30°33′N in the eastern suburbs of the city of Wuhan, capital of Hubei Province in central China. It is a typical shallow-bottomed, freshwater ecosystem nestling in the middle reaches of the mighty Changjiang (Yangtze) River. With a total surface area of 27.8 square and a mean depth of 2.2 meters, it sprawls in a drainage basin covering an area of 187 square kilometers. The station is situated on the southwest bank of the lake. 展开更多
关键词 DONGHU lake ecosystem EXPERIMENTAL STATION
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Microwave assisted digestion followed by ICP-MS for determination of trace metals in atmospheric and lake ecosystem 被引量:11
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作者 Manan Ahmed Ying Hui Chin +1 位作者 Xinxin Guo Xing-Min Zhao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第5期1-10,共10页
The study of trace metals in the atmosphere and lake water is important due to their critical effects on humans,aquatic animals and the geochemical balance of ecosystems. The objective of this study was to investigate... The study of trace metals in the atmosphere and lake water is important due to their critical effects on humans,aquatic animals and the geochemical balance of ecosystems. The objective of this study was to investigate the concentration of trace metals in atmospheric and lake water samples during the rainy season(before and after precipitation)between November and December 2015. Typical methods of sample preparation for trace metal determination such as cloud point extraction,solid phase extraction and dispersive liquid–liquid micro-extraction are time-consuming and difficult to perform; therefore,there is a crucial need for development of more effective sample preparation procedure. A convection microwave assisted digestion procedure for extraction of trace metals was developed for use prior to inductively couple plasma-mass spectrometric determination. The result showed that metals like zinc(133.50–419.30 μg/m^3)and aluminum(53.58–378.93 μg/m^3)had higher concentrations in atmospheric samples as compared to lake samples before precipitation.On the other hand,the concentrations of zinc,aluminum,chromium and arsenic were significantly higher in lake samples after precipitation and lower in atmospheric samples. The relationship between physicochemical parameters(pH and turbidity)and heavy metal concentrations was investigated as well. Furthermore,enrichment factor analysis indicated that anthropogenic sources such as soil dust,biomass burning and fuel combustion influenced the metal concentrations in the atmosphere. 展开更多
关键词 电感耦合等离子体质谱法 湖泊生态系统 痕量金属 微波消解 大气 测定 重金属浓度 样品制备
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Valuation of Lake and Marsh Wetlands Ecosystem Services in China 被引量:13
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作者 ZHANG Yiran ZHOU Demin +1 位作者 NIU Zhenguo XU Fengjiao 《Chinese Geographical Science》 SCIE CSCD 2014年第3期269-278,共10页
Wetlands are highly productive natural ecosystems, providing valuable goods and services. There is growing interest in transferring ecosystem service value from the existing wetlands studied to other wetlands ecosyste... Wetlands are highly productive natural ecosystems, providing valuable goods and services. There is growing interest in transferring ecosystem service value from the existing wetlands studied to other wetlands ecosystems at a large geographic scale. The benefit transfer method uses the known values from wetlands to predict the value of other wetland sites. This methodology requires only limited time and resources. The present study calculated the value of the ecological services provided by lake and marsh wetlands in China in terms of biodiversity indices, water quality indices and economic indices. Basic data on wetlands were obtained through remote sensing images. The results show that: 1) The total ecosystem service value of the lake and marsh wetlands in 2008 was calculated to be 8.1841 × 1010 United States Dollars(USD), with the marsh and lake wetlands contributing 5.6329 × 1010 and 2.5512 × 1010 USD, respectively. Values of marsh ecosystem service were concentrated in Heilongjiang Province(2.5516 × 1010 USD), Qinghai Province(1.2014 × 1010 USD), and Inner Mongolia Autonomous Region(1.1884 × 1010 USD). The value of the lakes were concentrated in Tibet Autonomous Region(6.223 × 109 USD), Heilongjiang(5.810 × 109 USD), and Qinghai(5.500 × 109 USD). 2) Waste treatment and climate regulation services contributed to 26.29% and 24.74% respectively, of the total ecosystem service value of the marsh wetlands. Hydrological regulation and waste treatment contributed to 41.39% and 32.75%, respectively, of the total ecosystem service value of the lake wetlands. 3) The total ecological service value of the lake and marsh wetlands was 54.64% of the total service value of natural grassland ecosystems and 30.34% of the total service value of forests ecosystems in China. 展开更多
关键词 生态系统服务价值 沼泽湿地 中国森林 生态系统服务功能 生态服务价值 生物多样性指数 湖泊湿地 估值
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Dynamic phosphorus budget for lake-watershed ecosystems 被引量:2
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作者 LIU Yong GUO Huai-cheng +3 位作者 WANG Li-jing DAI Yong-li ZHANG Xiu-min LI Zi-hai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第3期596-603,共8页
Lake eutrophication caused by excess phosphorus(P) loading from point sources(PS) and nonpoint sources(NPS) is a persistent and serious ecological pro blem in China. A phosphorus budget, based on material flow analysi... Lake eutrophication caused by excess phosphorus(P) loading from point sources(PS) and nonpoint sources(NPS) is a persistent and serious ecological pro blem in China. A phosphorus budget, based on material flow analysis(MFA) and sys tem dynamic(SD), is proposed and applied for the agriculture-dominated Qionghai Lake watershed located in southwestern China. The MFA-SD approach will not only cover the transporting process of P in the lake-watershed ecosystems, but also c an deal with the changes of P budget due to the dynamics of watershed. P inflows include the fertilizer for agricultural croplands, soil losses, domestic sewage discharges, and the atmospheric disposition such as precipitation and dust sink ing. Outflows are consisted of hydrologic export, water resources development, f ishery and aquatic plants harvesting. The internal P recycling processes are als o considered in this paper. From 1988 to 2015, the total P inflows for Lake Qio nghai are in a rapid increase from 35.65 to 78.73 t/a, which results in the risi ng of P concentration in the lake. Among the total P load 2015, agricultural los s and domestic sewage account for 70.60% and 17.27% respectively, directly relat ed to the rapid social-economic development and the swift urbanization. Future m anagement programs designed to reduce P inputs must be put into practices in the coming years to ensure the ecosystem health in the watershed. 展开更多
关键词 湖泊 水体污染 系统动力学 生态系统
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Ecosystem Health Assessment of Honghu Lake Wetland of China Using Artificial Neural Network Approach 被引量:21
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作者 MO Minghao WANG Xuelei +3 位作者 WU Houjian CAI Shuming Xiaoyang ZHANG WANG Huiliang 《Chinese Geographical Science》 SCIE CSCD 2009年第4期349-356,共8页
Honghu Lake,located in the southeast of Hubei Province,China,has suffered a severe disturbance during the past few decades.To restore the ecosystem,the Honghu Lake Wetland Protection and Restoration Demonstration Proj... Honghu Lake,located in the southeast of Hubei Province,China,has suffered a severe disturbance during the past few decades.To restore the ecosystem,the Honghu Lake Wetland Protection and Restoration Demonstration Project(HLWPRDP) has been implemented since 2004.A back propagation(BP) artificial neural network(ANN) approach was applied to evaluatinig the ecosystem health of the Honghu Lake wetland.And the effectiveness of the HLWPRDP was also assessed by comparing the ecosystem health before and after the project.Particularly,12 ecosystem health indices were used as evaluation parameters to establish a set of three-layer BP ANNs.The output is one layer of ecosystem health index.After training and testing the BP ANNs,an optimal model of BP ANNs was selected to assess the ecosystem health of the Honghu Lake wetland.The result indicates that four stages can be identified based on the change of the ecosystem health from 1990 to 2008 and the ecosystem health index ranges from morbidity before the implementation of HLWPRDP(in 2002) to middle health after the implementation of the HLWPRDP(in 2005).It demonstrates that the HLWPRDP is effective and the BP ANN could be used as a tool for the assessment of ecosystem health. 展开更多
关键词 生态系统健康评价 人工神经网络方法 洪湖湿地 BP人工神经网络 中国 湿地生态系统 健康评估 BP神经网络
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Ecosystem Health Assessment in Wuli Lake
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作者 FAN Li-min,WU Wei,HU Geng-dong,QU jian-hong,MENG Shun-long,SONG Chao,QIU Li-ping,CHEN jia-zhang Freshwater Fisheries Research Centre,Chinese Academy of Fishery Sciences Fishery Eco-environment Monitoring Center of Lower Reaches of Yangtze River,Ministry of Agriculture /Key Open Laboratory of Ecological Environment and Resources of Inland Fisheries,Wuxi 214081,China 《Asian Agricultural Research》 2012年第8期64-67,共4页
Using the method of trophic state-composite index (TSI-CI ) and the 12 months of monitoring data in 2010,we carry out initial exploration of the status of ecosystem health in Wuli Lake. First,we select four indicators... Using the method of trophic state-composite index (TSI-CI ) and the 12 months of monitoring data in 2010,we carry out initial exploration of the status of ecosystem health in Wuli Lake. First,we select four indicators,Chla,SD,TP and TN,to conduct trophic state assessment using weighted index method; then after selecting physical,chemical and biological indicators to conduct nondimensionalization processing,we calculate the composite index and conduct comprehensive assessment. The results show that in 2010,the status of ecosystem health in Wuli Lake was the best in July,worst in August; when the composite trophic state indicators with Chla as the representative increase or decrease significantly and cross different nutritional grades,TSI will significantly deviate from CI,and the relationship between the two in the other time is not prominent. 展开更多
关键词 Wuli lake ecosystem HEALTH ASSESSMENT TROPHIC STAT
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Current Situation and Ideas of Protection and Restoration of Aquatic Ecosystems in Rivers and Lakes of China
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作者 Zhang Yaohua Hu Mingming +1 位作者 Zhu Xi Wang Zhen 《Meteorological and Environmental Research》 CAS 2016年第3期27-33,共7页
Based on the investigation and analysis of protection and restoration of aquatic ecosystems in rivers and lakes of China,the ideas and measures of restoring aquatic ecosystems were proposed to build healthy aquatic ec... Based on the investigation and analysis of protection and restoration of aquatic ecosystems in rivers and lakes of China,the ideas and measures of restoring aquatic ecosystems were proposed to build healthy aquatic ecosystems of rivers and lakes in China,such as setting scientific and clear goals,improving the standard adopted by wastewater treatment plants,controlling sources of pollutants and intercepting pollutants,collection of blue-green algae,water transfer,dredging,reducing the quantity of blue-green algae,restoring reed wetlands on a large scale,combing dredging and base raise of restored reed wetlands,making full use of microorganisms,and implementing effective management,technology integration and innovation. 展开更多
关键词 水生生态系统 湖泊 河流 中国 保护 生态系统恢复 生态系统健康 芦苇湿地
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Construction and Protection of Qionghai Lake Wetland Ecosystems 被引量:1
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作者 Kaiwei CHEN 《Asian Agricultural Research》 2013年第4期76-78,82,共4页
Wetland is closely related to survival, reproduction and development of human beings. Due to population growth, industrialization, urbanization and agricultural modernization, wetland ecosystems are suffered from huge... Wetland is closely related to survival, reproduction and development of human beings. Due to population growth, industrialization, urbanization and agricultural modernization, wetland ecosystems are suffered from huge pressure of human society and the wetland ecological environment becomes extremely vulnerable. On the basis of analyzing current situations of Qionghai Lake wetland in Xichang City of Sichuan Province, this paper discussed the significance of Qionghai wetland construction and protection, and offered countermeasures and recommendations for solving existing problems in Qionghai wetland. 展开更多
关键词 WETLAND ecosystem CONSTRUCTION PROTECTION Qionghai
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Influences of 500 kV Transmission Lines on Wetland Ecosystem and Its Protective Countermeasures--A Case Study of the Lake Wetland Natural Reserve along the Yangtze River in Anqing City
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作者 Xia Shangguang Zhao Yuan 《Meteorological and Environmental Research》 CAS 2016年第4期17-22,共6页
The impact of 500 kV transmission lines of Anqing power plant across the lake wetland reserve along the Yangtze River on the safety of the ecosystem was taken as the researched object.The power frequency electric fiel... The impact of 500 kV transmission lines of Anqing power plant across the lake wetland reserve along the Yangtze River on the safety of the ecosystem was taken as the researched object.The power frequency electric field intensity(PFEFI),power frequency magnetic field intensity(PFMFI),radio interference,construction noise,vegetation destruction and the influence on water quality were investigated and monitored,and the influences of PFEFI,PFMFI,radio interference and construction noise on wild animals,especially the habitats and migration of birds were mainly researched.The direct and indirect influences on the surrounding environment as well as plants and animals in sensitive areas were analyzed and predicted.The results firstly showed there existed a 182 400m^3 stereo-space(PFEFI>4kV/m)which made flying birds unsafe under the lowest height 11 mof the lines,which fills the gap in the research of this field.Finally,some operational protection countermeasures were put forward at the current technical level to achieve the win-win goal of economic development and natural protection. 展开更多
关键词 Ultra-high-voltage transmission line Electromagnetic pollution lake WETLAND ecosystem safety Protective measures China
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Paragenese of the vegetation in ecosystems contact zones (in Lake Baikal basin)
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作者 Alexander Sizykh Victor Voronin +1 位作者 Michail Azovsky Svetlana Sizykh 《Natural Science》 2012年第5期271-275,共5页
Phytocenoses in the ecosystems contact zones are characterized by a rather complex structural and dynamical more than one features and by specific development characters under definite physical and geographical condit... Phytocenoses in the ecosystems contact zones are characterized by a rather complex structural and dynamical more than one features and by specific development characters under definite physical and geographical conditions. Unlike zonal vegetation, such phytocenoses respond to all environment changes more rapidly. The structure of such phytocenoses allows to determine the way this or that scenarios of climate change would develop at any level of more than one ecosystems. A possibility to use the notion “paragenese” for characterization of phytocenoses under contrast conditions is considered. Paragenese is the development of phytocenoses which are not related to zonal vegetation types by their composition and structure. Probably, the communities from ecosystems contact zones are to be related to a particular “type” of vegetation. Phytocenoses in the contact of light coniferous taiga and extrazonal steppes, as well as relations between zonal forest-steppe at main areas of Lake Baikal basin served as examples for justification of use of the notion “paragenese” to characterize the development of such communities. 展开更多
关键词 Paragenese Phytocenoses lake BAIKAL BASIN ecosystemS
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Using Remote Sensing Technologies for the Research of the Transformation of Ecosystems (Case Study: Lake Sevan Basin)
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《Journal of Earth Science and Engineering》 2013年第6期363-370,共8页
关键词 流域生态系统 盆地 案例分析 遥感技术 归一化植被指数 土地覆盖类型 LANDSAT 转化
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Characteristic Relationships between Phosphorous Accrual, Ecosystem Aspects and Water Level Fluctuations in Tropical Lakes: Naivasha Ramsar Site, Kenya
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作者 Beatrice N. Obegi George M. Ogendi +4 位作者 Reuben Omondi Boston J. Siriba George N. Morara Nehemiah M. Rindoria Paul Orina 《Journal of Geoscience and Environment Protection》 2021年第1期53-67,共15页
Hydrological dynamics affect water levels and thus affecting ecosystem structure and functions. Lake levels in tropical ecosystems affect phosphorous input through runoff from adjacent watersheds. The resultant biolog... Hydrological dynamics affect water levels and thus affecting ecosystem structure and functions. Lake levels in tropical ecosystems affect phosphorous input through runoff from adjacent watersheds. The resultant biological community, water and sediment quality of the lakes due to water level changes is a reflection of the geology of the area and the anthropogenic activities in the watershed. The study conducted between January 2018 and December 2019 was to explore relationships between the phosphorous input and Water Level Fluctuations (WLF) recorded by Water Resource Authority (WRA). Lake water samples were analyzed in the laboratory for phosphorous using molybdenum blue-ascorbic method and recorded using spectrophotometer. Chlorophyll-<em>a</em> was determined by extracting a filtered sample with 15 ml acetone and incubating overnight and thereafter read using a double beam spectrophotometer. Total Suspended Solids (TSS) was determined by filtering 200 ml of a water sample and dried overnight at 105<span style="white-space:nowrap;">°</span>C. The lowest and highest phosphorous concentrations recorded were 0.2 mg/l and 0.42 mg/l at NST7 and NST2, respectively. Measurements of Chlorophyll-<em>a</em> were 0.32 mg/l and 0.42 mg/l at NST9 and NST2, respectively. Secchi transparency measurements were 32.9 cm at NST3 and 84 cm at NST1. The highest and lowest TSS concentrations were 0.14 mg/l and 0.13 mg/l at NTS1 and NST8, respectively. The hydrodynamic regime in most tropical lakes plays a significant role in the re-reaction of phosphorous that consequently influences productivity. Tropical lakes have extreme lake level fluctuations which accelerate the production process. The influence of water level changes on aquatic productivity is crucial in most tropical lakes and should be taken into consideration when assessing the environmental impacts. 展开更多
关键词 lake Level Fluctuations Total Phosphorous ecosystem Aspects lake Naivasha
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Sustainable Ecosystem Management versus Economic Exploitation: A Case Study of Lake Naivasha Basin, Kenya
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作者 P.M. Njogu J.J. Kitetu J.M. Keriko 《Journal of Environmental Science and Engineering》 2010年第7期50-55,共6页
关键词 经济开发 生态系统管理 肯尼亚 淡水生态系统 底栖生物群落 盆地 案例 废水排放
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Building a Database for the Future:Humans and Lakes within Ecosystems
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作者 LIN Hebin Jeffrey THORNTON Thomas SLAWSKI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期186-187,共2页
1 Introduction Fresh or saline,lakes constantly exchange with other water bodies on the Earth.Together,they form a crucial part of the water cycle–one of the most important ecosystem functions supporting humans and o... 1 Introduction Fresh or saline,lakes constantly exchange with other water bodies on the Earth.Together,they form a crucial part of the water cycle–one of the most important ecosystem functions supporting humans and other biological communities.Lakes have provided invaluable and irreplaceable ecosystem services(benefits)for 展开更多
关键词 ecosystem FUNCTIONS ecosystem services DATABASE lakeS RESOURCE management
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Ecosystem Service Flow Insights into Horizontal Ecological Compensation Standards for Water Resource: A Case Study in Dongjiang Lake Basin, China 被引量:7
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作者 XU Jie XIAO Yu +1 位作者 XIE Gaodi JIANG Yuan 《Chinese Geographical Science》 SCIE CSCD 2019年第2期214-230,共17页
Water supply services(WSSs) are critical for the regional water balance and water circulation, but relevant studies have not established the relationship between WSSs and human well-being. This research identifies the... Water supply services(WSSs) are critical for the regional water balance and water circulation, but relevant studies have not established the relationship between WSSs and human well-being. This research identifies the scope of areas that benefit from WSSs from an ecosystem service flow perspective. Moreover, the path and quantity of the flow of WSSs are simulated to provide a scientific theoretical basis for ecosystem service management and ecological compensation. The Dongjiang Lake Basin is a national priority river basin in China where ecological compensation pilot programmes concerning water resources are top priorities. Dongjiang Lake Basin experienced an increase and then a decrease in the overall supply of water, with an average net water supply of 1096–1500 mm for the years 1995, 2000, 2005 and 2010. The water demand increased each year in service beneficiary areas(SBAs), varying from 387 to 580 mm. Overall, Dongjiang Lake Basin met the net water demands of the actual SBAs in the lower reaches, but a gap in the water supply and demand emerged gradually. This research provides an understanding of the functional mechanisms for the provision, demand and flow of WSSs and provides a scientific theoretical basis for ecosystem service management and ecological compensation. 展开更多
关键词 ecosystem service flow water supply services Dongjiang lake Basin SPATIOTEMPORAL patterns HORIZONTAL ECOLOGICAL compensation
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Less Mixing Can Affect Lake's Ecosystem
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作者 E.Sohn 《数理天地(高中版)》 2005年第7期50-,共1页
Lakescanbelikebowlsofsoupinthemicrowave:Theyneedalittlestirringeverynowandthen.Otherwise,alltheheatendsupontop.That’sexactlywhat’shappenedinrecentyearstoAfrica'sLakeTanganyika,scientistsarereporting.
关键词 Less Mixing Can Affect lake’s ecosystem
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Impact of LUCC on Ecosystem Service Value in the Up and Middle Reaches of Dongting Lake Basin,China 被引量:1
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作者 XIONG Ying WANG Kelin LIU Chun 《湿地科学》 CSCD 2009年第4期327-334,共8页
Supported by geographical information system,using Costanza method and referring to terrestrial ecosystem service value in China,the influence of land use and land cover change(LUCC)between 1980 and 2000 on ecosystem ... Supported by geographical information system,using Costanza method and referring to terrestrial ecosystem service value in China,the influence of land use and land cover change(LUCC)between 1980 and 2000 on ecosystem service value in the up and middle reaches of Dongting Lake basin was analyzed in this study.The results showed that the estimated value of ecosystem services decreased 8.416 9×108 CNY over a 21-year period,and the main reasons were that the land for forest use was exploited for cropland and construction land use in study area.Further analysis results showed that the value of single ecosystem service function such as gas regulation,climate regulation,soil formation and conservation,biodiversity conservation,raw materials as well as recreation decreased significantly;and that of provision of water conservation,waste treatment and food production increased obviously in the area.The results of coefficient sensitivity analysis indicated that these estimates were reliable. 展开更多
关键词 生态学 LUCC 湿地 地貌学
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基于水供需服务流及外溢价值核算的太湖流域横向生态补偿机制
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作者 王健 曹巍 黄麟 《生态学报》 CAS CSCD 北大核心 2024年第3期955-965,共11页
通过生态补偿协调流域内经济发展与生态保护的关系、缓解上下游利益相关者之间的矛盾是保障流域经济社会可持续发展的关键措施,而流域生态补偿核定的关键在于两点:一是如何模拟并量化水供需服务流动的流向、流量、流速及路径以明确供需... 通过生态补偿协调流域内经济发展与生态保护的关系、缓解上下游利益相关者之间的矛盾是保障流域经济社会可持续发展的关键措施,而流域生态补偿核定的关键在于两点:一是如何模拟并量化水供需服务流动的流向、流量、流速及路径以明确供需双方及其空间关系;二是如何实现栅格尺度-地理单元-行政单元的尺度推演以实现不同行政单元之间生态系统服务的盈余、占用、外溢核算。整合卫星遥感、经济社会统计、水文气象观测等多源异构数据,集成水量平衡、水供需服务流动、生态价值核算等方法,构建了基于水供需流动及其外溢价值核算的流域横向生态补偿标准核定框架,利用D8流向法解决了水供需服务流动的流向、流量、流速及路径模拟与量化,实现了“栅格尺度-地形单元-行政单元”空间尺度推演的外溢价值核算,形成了流域内横向水生态补偿资金收取与分配方案。以太湖流域为例,在全面分析水资源外溢、占用及其价值的基础上,解析了县域尺度的水供需时空关系、流动路径及属性特征,辅以水质指标进而明确界定了责任方与补偿对象,形成了补偿资金收取与分配方案。结果表明,太湖流域水供需双方界线清晰、服务流近似于自然汇流过程,供给方以流域西部、西南部、中部县域为主,特别是西部至中部的县域,应受偿资金较多,平均各县应受偿资金比例超过2%/a,应受偿资金最多的嘉善区,比例超过19.66%/a;需求方聚集于流域中部、东部,特别是黄浦江自然汇流沿岸县域,应收取补偿资金较多,平均各县应收取资金比例超过5%/a,应收取最多的浦东新区,比例超过15.48%/a;净补偿资金基本呈现西高东低的分布特征,流域的大部分城市核心区的县域净补偿资金为负值。研究的核定框架、量化核算方法、资金统筹方案可应用到其他流域的横向生态补偿机制构建,实现流域内部与流域之间生态保护和经济发展的整体协调。 展开更多
关键词 水供需服务流 外溢价值核算 横向生态补偿 补偿标准核定 太湖流域
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一类考虑空间异质环境的湖泊生态系统模型的全局稳定性
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作者 喻梦瑶 黄刚 《应用数学》 北大核心 2024年第1期115-123,共9页
本文研究一类空间异质环境下具有扩散的湖泊生态系统模型.引入空间异质环境影响,模型中浮游动物的扩散及相互作用系数具有空间依赖性.本文首先证明了模型解的全局存在和唯一性以及共存平衡解的存在唯一性,通过构造Lyapunov泛函,建立了... 本文研究一类空间异质环境下具有扩散的湖泊生态系统模型.引入空间异质环境影响,模型中浮游动物的扩散及相互作用系数具有空间依赖性.本文首先证明了模型解的全局存在和唯一性以及共存平衡解的存在唯一性,通过构造Lyapunov泛函,建立了模型非齐次共存平衡解的全局渐近稳定性条件,并通过数值模拟验证了理论结果.本文推广了含有外来有机物的湖泊生态系统模型,进一步证明了空间异质环境下的扩散不会改变湖泊生态系统共存平衡解的稳定性. 展开更多
关键词 湖泊生态系统 扩散 空间异质性 LYAPUNOV泛函 全局稳定性
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