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Inconsistent increasing of climate potential productivity resulting from global warming and land use transitions in the Dongting Lake Basin,from 2000 to 2020
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作者 WANG Ji-ren ZHENG Jian +2 位作者 SU Jian ZHENG Bo-hong SUN Zhao-qian 《Journal of Mountain Science》 SCIE CSCD 2023年第7期1954-1967,共14页
In the face of global warming and increasing impervious surfaces,quantifying the change of climate potential productivity(CPP)is of great significance for the food production planning.Targeting the Dongting Lake Basin... In the face of global warming and increasing impervious surfaces,quantifying the change of climate potential productivity(CPP)is of great significance for the food production planning.Targeting the Dongting Lake Basin,which is a key area for food production in China,this paper uses meteorological data,as well as Climate Change Initiative Land Cover,and Shuttle Radar Topography Mission digital elevation model to investigate the CPP and its changes from 2000 to 2020.The suitability of land for cultivation(SLC),and the land use/land cover change(LUCC)are also considered.The results showed that the CPP varied from 9,825 to 20,895 kg ha^(-1).Even though the newly added impervious surfaces indirectly resulted in the decrease of CPP by of 9.81×10~8 kg,overall,the CPP increased at an average rate of 83.7 kg ha^(-1)a^(-1).Global warming is the strongest driver behind CPP increase,and CPP has played an important role in the conversions between cultivated land and other land types.The structure of land types tends to be optimized against this challenge. 展开更多
关键词 Land cultivation Land use/land cover change Climate potential productivity Global warming dongting lake Basin
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Local and regional flood frequency analysis based on hierarchical Bayesian model in Dongting Lake Basin,China 被引量:1
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作者 Yun-biao Wu Lian-qing Xue Yuan-hong Liu 《Water Science and Engineering》 EI CAS CSCD 2019年第4期253-262,共10页
This study developed a hierarchical Bayesian(HB)model for local and regional flood frequency analysis in the Dongting Lake Basin,in China.The annual maximum daily flows from 15 streamflow-gauged sites in the study are... This study developed a hierarchical Bayesian(HB)model for local and regional flood frequency analysis in the Dongting Lake Basin,in China.The annual maximum daily flows from 15 streamflow-gauged sites in the study area were analyzed with the HB model.The generalized extreme value(GEV)distribution was selected as the extreme flood distribution,and the GEV distribution location and scale parameters were spatially modeled through a regression approach with the drainage area as a covariate.The Markov chain Monte Carlo(MCMC)method with Gibbs sampling was employed to calculate the posterior distribution in the HB model.The results showed that the proposed HB model provided satisfactory Bayesian credible intervals for flood quantiles,while the traditional delta method could not provide reliable uncertainty estimations for large flood quantiles,due to the fact that the lower confidence bounds tended to decrease as the return periods increased.Furthermore,the HB model for regional analysis allowed for a reduction in the value of some restrictive assumptions in the traditional index flood method,such as the homogeneity region assumption and the scale invariance assumption.The HB model can also provide an uncertainty band of flood quantile prediction at a poorly gauged or ungauged site,but the index flood method with L-moments does not demonstrate this uncertainty directly.Therefore,the HB model is an effective method of implementing the flexible local and regional frequency analysis scheme,and of quantifying the associated predictive uncertainty. 展开更多
关键词 Flood frequency analysis Hierarchical Bayesian model Index flood method Generalized extreme value distribution dongting lake Basin
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Carbon,nitrogen and phosphorus coupling relationships and their influencing factors in the critical zone of Dongting Lake wetlands,China
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作者 Yan-hao Wu Nian-qing Zhou +2 位作者 Zi-jun Wu Shuai-shuai Lu Yi Cai 《Journal of Groundwater Science and Engineering》 2022年第3期250-266,共17页
Wetland is a transition zone between terrestrial and aquatic ecosystems,and is the source and sink of various biogenic elements in the earth’s epipelagic zone.In order to investigate the driving force and coupling me... Wetland is a transition zone between terrestrial and aquatic ecosystems,and is the source and sink of various biogenic elements in the earth’s epipelagic zone.In order to investigate the driving force and coupling mechanism of carbon(C),nitrogen(N)and phosphorus(P)migration in the critical zone of lake wetland,this paper studies the natural wetland of Dongting Lake area,through measuring and analysing the C,N and P contents in the wetland soil and groundwater.Methods of Pearson correlation,non-linear regression and machine learning were employed to analyse the influencing factors,and to explore the coupling patterns of the C,N and P in both soils and groundwater,with data derived from soil and water samples collected from the wetland critical zone.The results show that the mean values of organic carbon(TOC),total nitrogen(TN)and total phosphorus(TP)in groundwater are 1.59 mg/L,4.19 mg/L and 0.5 mg/L,respectively,while the mean values of C,N and P in the soils are 18.05 g/kg,0.86 g/kg and 0.52 g/kg.The results also show that the TOC,TN and TP in the groundwater are driven by a variety of environmental factors.However,the concentrations of C,N and P in the soils are mainly related to vegetation abundance and species which influence each other.In addition,the fitted curves of wetland soil C-N and C-P appear to follow the power function and S-shaped curve,respectively.In order to establish a multivariate regression model,the soil N and P contents were used as the input parameters and the soil C content used as the output one.By comparing the prediction effects of machine learning and nonlinear regression modelling,the results show that coupled relationship equation for the C,N and P contents is highly reliable.Future modelling of the coupled soil and groundwater elemental cycles needs to consider the complexity of hydrogeological conditions and to explore the quantitative relationships among the influencing factors and chemical constituents. 展开更多
关键词 dongting lake Wetland critical zone CARBON Nitrogen and phosphorus Driving factors Coupling mechanisms
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Flood management of Dongting Lake after operation of Three Gorges Dam 被引量:5
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作者 Xi-jun Lai Zi-ming Wang 《Water Science and Engineering》 EI CAS CSCD 2017年第4期303-310,共8页
Full operation of the Three Gorges Dam(TGD) reduces flood risk of the middle and lower parts of the Yangtze River Basin. However,Dongting Lake, which is located in the Yangtze River Basin, is still at high risk for po... Full operation of the Three Gorges Dam(TGD) reduces flood risk of the middle and lower parts of the Yangtze River Basin. However,Dongting Lake, which is located in the Yangtze River Basin, is still at high risk for potentially severe flooding in the future. The effects of the TGD on flood processes were investigated using a hydrodynamic model. The 1998 and 2010 flood events before and after the operation of the TGD, respectively, were analyzed. The numerical results show that the operation of the TGD changes flood processes, including the timing and magnitude of flood peaks in Dongting Lake. The TGD can effectively reduce the flood level in Dongting Lake, which is mainly caused by the flood water from the upper reach of the Yangtze River. This is not the case, however, for floods mainly induced by flood water from four main rivers in the catchment. In view of this, a comprehensive strategy for flood management in Dongting Lake is required. Non-engineering measures, such as warning systems and combined operation of the TGD and other reservoirs in the catchment, as well as traditional engineering measures, should be further improved. Meanwhile, a sustainable philosophy for flood control, including natural flood management and lake restoration, is recommended to reduce the flood risk. 展开更多
关键词 THREE Gorges DAM FLOOD control Water LEVEL HYDRODYNAMIC model dongting lake
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Ichthyoplankton recruitment from mainstream of the Changjiang River into the Dongting Lake, the second largest freshwater lake in China 被引量:2
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作者 MA Qin LI Mingzheng +2 位作者 QIN Xiangchao LIU Huanzhang CAO Wenxuan 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第3期1090-1101,共12页
Floodplains are important and distinctive ecosystems around the world,and the recruitment of ichthyoplankton from river to floodplain lakes is crucial to maintain this unique ecosystem.However,this process has not bee... Floodplains are important and distinctive ecosystems around the world,and the recruitment of ichthyoplankton from river to floodplain lakes is crucial to maintain this unique ecosystem.However,this process has not been well documented.In this study,ichthyoplankton were sampled to investigate the details of ichthyoplankton recruitment from the Changjiang(Yangtze)River to the Dongting Lake via a floodway channel,the Songzi River,from May to July in 2013 and 2014.During the study period,41 species of eggs and larvae were sampled.Among the samples,16 were river-lake migratory species(RL),representing 23.5%of the species in the Dongting Lake.In 2013,an estimated 130 million eggs and 3180 million larvae drifted through the sampling section,and in 2014,an estimated 1 060 million eggs and 1040 million larvae drifted through the sampling section.The amount of eggs and larvae of RL reached 3 210 million in 2013 and 1 850 million in 2014,respectively.These results demonstrated the importance of ichthyoplankton recruitment from the river to the lake,as species diversity will decrease sharply without this recruitment.Canonical correspondence analysis(CCA)showed that water temperature and water flow are the two most important factors influencing the spawning activities of fish.To maintain the high fish diversity in the Changjiang floodplain,we suggest to irrigate the channel to increase water discharge and increase the transport of ichthyoplankton from the Changjiang mainstream into the Dongting Lake. 展开更多
关键词 ICHTHYOPLANKTON RECRUITMENT CHANGJIANG FLOODPLAIN dongting lake
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Study on the Water Quality and Protection Measures of Dongting Lake 被引量:4
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作者 Zhangquan ZENG Canming ZHANG +3 位作者 Xiquan LI Nan Yang Yandong NIU Zijian WU 《Asian Agricultural Research》 2015年第1期57-60,共4页
From nitrogen and phosphorus,chemical oxygen demand,phytoplankton,and eutrophication,this article analyzes the current situation of water quality in the Dongting Lake area,and discusses the factors influencing the wat... From nitrogen and phosphorus,chemical oxygen demand,phytoplankton,and eutrophication,this article analyzes the current situation of water quality in the Dongting Lake area,and discusses the factors influencing the water quality of Dongting Lake. Based on the actual production,geographic characteristics and outstanding problem of grim water pollution situation in the Dongting Lake area,some specific proposed measures are put forward in order to provide the basis and reference for the future pollution control in the Dongting Lake area,such as strengthening the industrial pollution control,developing ecological agriculture,and enhancing ecological restoration and water quality early warning. 展开更多
关键词 dongting lake Water POLLUTION CURRENT SITUATION PR
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Analysis of deposition and erosion of Dongting Lake by GIS 被引量:1
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作者 Gao Jun-feng Zhang Chen +1 位作者 Jiang Jia-hu Huang Qun 《Journal of Geographical Sciences》 SCIE CSCD 2001年第4期22-30,共9页
The sediments of the Dongting Lake come from four channels (one of them was closed in 1959), connected with the Yangtze River, four tributaries (Lishui, Yuanjiang, Zishui and Xiangjiang) and local area, and some of th... The sediments of the Dongting Lake come from four channels (one of them was closed in 1959), connected with the Yangtze River, four tributaries (Lishui, Yuanjiang, Zishui and Xiangjiang) and local area, and some of them are transported into the Yangtze River in Chenglingji, which is located at the exit of the Dongting Lake, some of them deposit into drainage system in the lake region and the rest deposit into the lake. The annual mean sediment is 166,555x104 t, of which 80% come from the four channels, 18% from the four tributaries and 2% from local area, whereas 26% of the total sediments are transported into the Yangtze River and 74% deposited into the lake and the lake drainage system. Based on topographic maps of 1974, 1988 and 1998, and the spatial analysis method with geographic information system (GIS), changes in sediment deposition and erosion are studied in this paper. By overlay analysis of 1974 and 1988, 1988 and 1998, erosion and sediments deposition areas are defined. The main conclusions are: (1) sediment rate in the lake is larger than erosion rate from 1974 to 1998. The mean deposition in the lake is 0.43 m; (2) annual sediment deposition is the same between 1974-1988 and 1988-1998, but the annual volume of deposition and erosion of 1988-1998 is bigger than that in 1974-1988; (3) before the completion of the Three Gorges Reservoir, there will be 7.82x108 m3 of sediments deposited in the lake, which would make the lake silted up by 0.33 m; (4) in the lake, the deposition area is found in the north of the east Dongting Lake, the south-west of the south Dongting Lake, and the east of the west Dongting Lake; while the eroded area is in the south of the east Dongting Lake, the middle of the south Dongting Lake, the west of the west Dongting Lake, as well as Xiangjiang and Lishui river flood channels. 展开更多
关键词 dongting lake SEDIMENT DEPOSITION and EROSION SPATIAL distribution GIS
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A statistical approach for determining the environment impact of surface sediments from the Dongting Lake area, central China 被引量:11
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作者 YAO Zhigang 《Chinese Journal Of Geochemistry》 EI CAS 2009年第1期97-104,共8页
The Dongting Lake, the second biggest freshwater lake in China, consists of three wetlands of national importance, namely the East Dongting Lake, the South Dongting Lake, and the West Dongting Lake. Surface sediments ... The Dongting Lake, the second biggest freshwater lake in China, consists of three wetlands of national importance, namely the East Dongting Lake, the South Dongting Lake, and the West Dongting Lake. Surface sediments were sampled from 57 locations across the lake. Nutrient concentrations [total organic carbon (TOC), total N (TN) and total P (TP)] and 16 element concentrations (Al, As, B, Ca, Cd, Cr, Cu, K, Fe, Hg, Mn, Ni, Pb, Si, Ti and Zn) in the sediments were measured to investigate the impact of industrialization along the lake’s coastline and several tributaries on the profiles of nutrients and heavy metals in the lake’s surface sediments. R-mode cluster analysis (CA) was used to integrate geochemical data. The result showed that euthophication of the Dongting Lake resulted mainly from TN and TOC. The main polluting trace metals are Hg, As, Cd, Zn, Pb and Mn, which are largely adsorbed on clay minerals or Fe/Mn oxides, or deposited as carbonates. Principal component analysis (PCA) revealed the source of micropollutants. The worst affected district by heavy metals is the East Dongting Lake, the pollution sources may originate mainly from the Xiangjiang drainage area. The results demonstrated that multivariate methods are the potentially great tools for the interpretation of the environmental data on lake sediments. 展开更多
关键词 重金属 沉积物 多元方差分析 洞庭湖 地球化学
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Landscape ecological assessment and eco-tourism development in the South Dongting Lake Wetland, China 被引量:19
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作者 HE Ping 1,2, WANG Bao-zhong 1,3 (1.Central South Forestry University, Zhuzhou 412006, China 2.China International Engineering Consulting Corporation, Beijing 100044, China 3.Nanjing University, Nanjing 210093, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第2期271-278,共8页
As an important resource and the living environment of mankind, wetland has become gradually a highlight, strongly concerned and intensively studied by scientists and sociologists. The governments in the world and the... As an important resource and the living environment of mankind, wetland has become gradually a highlight, strongly concerned and intensively studied by scientists and sociologists. The governments in the world and the whole society have been paying more and more attention on it. The Dongting Lake of China is regarded as an internationally important wetland. For a rational development and protection of the wetland, an investigation and studied on its resources and its value to tourism in the South Dongting Lake was conducted, to create an assessment system of the ecological landscapes, and to evaluate qualitatively and quantitatively the value of wetland landscape to the eco-tourism. The results showed that the scenic value of the South Dongting Lake Wetland satisfied the criterion of AAAA grade of China national scenic attraction. The eco-tourism value of the landscape cultures in the South Dongting Lake Wetland was discussed with emphasis. It were formulated that a principle and frame of sustainable exploitation of the wetland landscapes and it was proposed as well that establishing a Wetland Park and developing eco-tourism in the South Dongting Lake. Wetland is a fragile ecosystem with low resistance to the impact of the exploitation. Thus, we must pay intensively attention to the influence of exploitation on the landscape, take the ecological risk in account to employ a right countermeasure and avoid the negative affection. 展开更多
关键词 南洞庭湖 湿地景观 生态旅游 中国 景观生态评价
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Eco-compensation effects of the wetland recovery in Dongting Lake area 被引量:18
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作者 XIONG Ying WANG Kelin 《Journal of Geographical Sciences》 SCIE CSCD 2010年第3期389-405,共17页
Eco 赔偿是为外部费用的成为主观的一台环境经济仪器。把农田还给湖是在中国的长江山谷恢复沼泽地生态系统功能的重要部分之一。湖恢复的工程是否能是成功的,取决于赔偿到失去了他们的原来的好处并且由把农田还给湖贡献了沼泽地生态系... Eco 赔偿是为外部费用的成为主观的一台环境经济仪器。把农田还给湖是在中国的长江山谷恢复沼泽地生态系统功能的重要部分之一。湖恢复的工程是否能是成功的,取决于赔偿到失去了他们的原来的好处并且由把农田还给湖贡献了沼泽地生态系统恢复的农民。瞄准东廷·莱克,的沼泽地恢复在这个区域的湖恢复和洪水控制的节目的实际实现被人口再定居的繁重的任务质问了,因此到达作为上面建议的学术目的,是为案例研究的一个理想的区域。基于领域调查和试验,这研究评估了重新安居的农民的利益损失,生态系统服务功能的增加的值由沼泽地恢复引起了,并且而且,为重定位的农民的 eco 赔偿的值由考虑农民赔偿呼吁的联合是计算的。为在东廷·莱克区域的重定位的农民的 eco 赔偿的值每由沼泽地生态系统恢复上的效果的合成分析的家庭是 6084.5 元。而且,这篇文章作为一个盒子拿了东廷·莱克区域由把农田还给湖学习并且探索eco赔偿的基本问题,那是谁应该付钱,谁应该被付,支付是多少并且什么支付工具是,它寻求了沼泽地恢复eco赔偿的机制并且为生态的恢复推动了人们热情。 展开更多
关键词 生态恢复 洞庭湖区 补偿效应 湿地
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Environmental Assessments of Trace Metals in Sediments from Dongting Lake, Central China 被引量:11
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作者 姚志刚 鲍征宇 高璞 《Journal of China University of Geosciences》 SCIE CSCD 2006年第4期310-319,共10页
To examine the degree of contamination in the Dongting Lake (洞庭湖) area, surface sediments samples were collected and investigated in this study. This lake lies in the south of the middle Yangtze River, and it is th... To examine the degree of contamination in the Dongting Lake (洞庭湖) area, surface sediments samples were collected and investigated in this study. This lake lies in the south of the middle Yangtze River, and it is the second largest fresh-water lake in China. These samples were analyzed for the concentrations of the following 6 elements (Cd, Cr, Cu, Ni, Pb and Zn) collected from 46 locations. The index of geo-accumulation was used to assess the degree of contamination of the total trace elements and the assessments showed that the contamination of Cd reached strong to very strong pollution. The speciation of metal in sediments was analyzed using the modified BCR (Community Bureau of Reference) sequential extraction technology and the water column-contamination risk was evaluated by the calculated contamination factors. The results of the speciation of metal indicated that more easily mobilized forms (exchangeable, water soluble, and acid soluble) were predominant for Cd, especially in the samples from East Dongting Lake. In contrast, the largest amount of lead was associated with the iron and manganese oxide fractions, and Cu, Zn, Cr, and Ni analyzed were mainly distributed in residual phase at an average percentage higher than 60% of the total metals. The potential risk to the lake’s water contamination was the highest in East Dongting Lake based on the calculated contamination factors. The assessment results using geo-accumulation index were compared with the information obtained by trace metal speciation and both results were consistent. 展开更多
关键词 洞庭湖 微量元素 环境变化 堆积物 环境污染
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Soil Respiration Characteristics and Its Relationship with Environmental Factors of Different Vegetation Types during Growing Season in Dongting Lake 被引量:1
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作者 Yan YANG Jie TANG +3 位作者 Yongjin LI Yuxi TANG Changzhu LI Lijuan JIANG 《Agricultural Biotechnology》 CAS 2019年第1期126-129,179,共5页
In order to ascertain the soil carbon flux characteristics of poplar plantations and crop communities in the Dongting Lake area during the growing season and their correlation with hydrothermal conditions,soil respira... In order to ascertain the soil carbon flux characteristics of poplar plantations and crop communities in the Dongting Lake area during the growing season and their correlation with hydrothermal conditions,soil respiration rate was monitored at fixed sites and time points with an LI-8100 A automated soil flux system.Meanwhile,the surface temperature and soil temperature and humidity were measured. The soil respiration variation in the two different vegetation types and its correlation with environmental factors were analyzed. The results showed that in the growing season,the diurnal variation curves of soil respiration rate in the two different vegetation types showed a single peak variation,but there was certain difference in the appearance time of the peak. The peak of the crop appeared around11: 00 am,while the peak of soil respiration in the poplar appeared around 13: 00. The soil respiration rate of the poplar was also significantly higher than that of the crop,and the average difference of soil respiration rate between the two was 3. 09 and 3. 55 μmol/( m^2·s) in April and August,respectively. Temperature and soil moisture were the main factors affecting soil respiration of the poplar plantation and crop community. Temperature had a greater effect on the soil respiration of the crop community,and soil humidity had a greater impact on soil respiration in the poplar plantation,showing a correlation coefficient reaching 0. 952. 展开更多
关键词 dongting lake GROWING SEASON Soil RESPIRATION rate Temperature Humidity CORRELATION
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Relationship between community type of wetland plants and site elevation on sandbars of the East Dongting Lake,China 被引量:5
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作者 ZHENG Jing-ming WANG Ling-yan +2 位作者 LI Su-yan ZHOU Jin-xing SUN Qi-xiang 《Forestry Studies in China》 CAS 2009年第1期44-48,共5页
Plant communities on sandbars were important,and restoration of degraded wetland were significant to biological conservation in the East Dongting Lake region.In this study,typical wetland community types on sandbars a... Plant communities on sandbars were important,and restoration of degraded wetland were significant to biological conservation in the East Dongting Lake region.In this study,typical wetland community types on sandbars and their site elevation were surveyed to explore relationship between community distribution and site elevation.Results show that eight major communities in this region were wetland communities dominated by Juncus effusus,Carex brevicuspis,Polygonum hydropiper,Salix triandra,Oenanthe Javanica,Phalaris arundinacea,Miscanthus sacchariflorus and Phragmites communis respectively.These communities had obvious constructive species and companion species,while site elevation could affect community composition and their species diversity.On sandbars in the East Dongting Lake,vegetation was largely composed of hygrophytes companied with a few mesophytes.The higher the site elevation was,the nearer the site was to the water,and the lower community diversity became.Except soil humidity and site elevation,growth period of plants after inundation could also affect species richness in the communities. 展开更多
关键词 湿地植物 社会关系 东洞庭湖 群落类型 网站 海拔 沙洲 物种多样性
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Comparison between BCR sequential extraction and geo-accumulation method to evaluate metal mobility in sediments of Dongting Lake, Central China 被引量:8
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作者 姚志刚 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第1期14-22,共9页
The form in which a metal exists strongly influences its mobility and thus, the effects on the environment. Operational methods of speciation analysis, such as the use of sequential extraction procedures, are commonly... The form in which a metal exists strongly influences its mobility and thus, the effects on the environment. Operational methods of speciation analysis, such as the use of sequential extraction procedures, are commonly applied. The Dongting Lake, the second largest fresh-water lake in China, contains three China wetlands of international importance, the East Dongting Lake, South Dongting Lake, and West Dongting Lake. In this work, an optimized BCR sequential extraction procedure was used to assess the environmental risk of Cd, Cr, Cu, Ni, Pb and Zn in contaminated sediment of the Dongting Lake. The procedure was evaluated by using a certified reference material, BCR701. The results of the partitioning study indicated that in the lake sediments, more easily mobilized forms (acid exchangeable) were predominant for Cd, particularly in the samples from the East Dongting Lake. In contrast, the largest amount of Pb was associated with the iron and manganese oxide fractions and Cu, Zn, Cr, and Ni analyzed were mainly distributed in residual phase at an average percentage greater than 60% of the total metals. The potential risk to the lake's water contamination was highest in the East Dongting Lake based on the calculated contamination factors. On the other hand, the total metal content was determined as well by inductively coupled plasma and mass spectrometry (ICP-MS) and assessed by using geo-accumulation index. The assessment results using geo-accumulation index were compared with the information on metal speciation. Both were correspondent with each other. 展开更多
关键词 中国 洞庭湖 重金属污染 物种形成 海口沉积指数
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Discussion on the Green Tax Stimulation Measure of Nitrogen Fertilizer Non-Point Source Pollution Control-Taking the Dongting Lake Area in China as a Case 被引量:8
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作者 XIANG Ping-an ZHOUYan +1 位作者 HUANG Huang ZHENG Hua 《Agricultural Sciences in China》 CAS CSCD 2007年第6期732-741,共10页
A study on designing the tax of nitrogen fertilizer can provide a new method for controlling nitrogen fertilizer non-point source pollution. The tax design of nitrogen fertilizer was discussed by utilizing the externa... A study on designing the tax of nitrogen fertilizer can provide a new method for controlling nitrogen fertilizer non-point source pollution. The tax design of nitrogen fertilizer was discussed by utilizing the external theory and the demand elasticity theory. The results indicated that the coefficient of price elasticity of nitrogen fertilizer demand is -0.21, which instructed that the market demand is in lack of elasticity in the short period and the impact of nitrogen fertilizer manufacturers is subtle. The 11 counties (cities and boroughs) in the Dongting Lake area in China, where the farmland nitrogen application surpassed the average ecological fertilization dosage, is listed to the taxation scope of nitrogen fertilizer tax. The environment loss will reduce 0.07 hundred million RMB yuan and the revenue will increase 0.89 hundred million RMB yuan in the country after levying on nitrogen fertilizer. The loss, which was brought by the decreasing food supplies production, will be 0.58 hundred million RMB yuan and the net social benefit will be 0.38 hundred million RMB yuan following revenue collection. The variation scope of the increasing expenditure of farmers will range from 0.95 to 1.49%. The variation scope of the income of farmers will range from -8.41 to 6.44%. The 5 areas, Yunxi Borough, Junshan Borough, Hanshou County, Jinshi City, and Ziyang Borough, had an increase in food supplies production after the revenue collection. The environment loss will reduce 0.01 hundred million RMB yuan and the revenue will increase 0.16 hundred million RMB yuan in the country after levying on nitrogen fertilizer. The economic benefits, which was brought by the increasing cereals production, will be 0.67 hundred million RMB yuan and the net social benefit will be 0.84 hundred million RMB yuan after revenue collection. The variation scope of the increasing expenditure of farmers will range from 0.95 to 1.06%. The variation scope of the increasing income of farmers will range from 0.69 to 6.44%. Considering the entire social welfare, taxation of nitrogen fertilizer will have more advantages than disadvantages in the Dongting Lake area. 展开更多
关键词 氮肥 非点源污染控制 绿色税收刺激措施 洞庭湖地区 化肥污染
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Assessment on soil fertility of Dongting Lake wetland area (China) based on GIS and fuzzy evaluation 被引量:6
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作者 李忠武 黄金权 +2 位作者 李裕元 郭旺 朱剑峰 《Journal of Central South University》 SCIE EI CAS 2011年第5期1465-1472,共8页
Using soil data of the Second National Field Survey,the soil fertility of wetland ecosystem of Dongting Lake was evaluated by using the technology of GIS and method of fuzzy evaluation.Integrated with the wetland actu... Using soil data of the Second National Field Survey,the soil fertility of wetland ecosystem of Dongting Lake was evaluated by using the technology of GIS and method of fuzzy evaluation.Integrated with the wetland actuality of Dongting Lake and particularity of paddy,seven factors (including soil organic matter,total nitrogen,total phosphorus,total potassium,available phosphorus,available potassium,and pH value),closely related with soil fertility,were chosen to establish the index system of synthetical evaluation.Based on the effect degree of each selected index on soil fertility,a judgment matrix was built,and the weight coefficient was determined by the method of correlation coefficient.Finally,under the support of the spatial analysis module of GIS (Geographic Information System),the spatial distribution properties of soil fertility in wetland ecosystem of Dongting Lake were studied.The results show that the soil fertility of Dongting Lake wetland ecosystem is not very good,and the area of type III and type IV achieves 69.8%.As a result,many countermeasures should be taken to improve the soil fertility.As for the spatial properties,the soil fertility level of central and west Dongting Lake is much higher than that of north and south part.The soil fertility of paddy field surpasses that of red soil,and the contents of soil organic matter and total nitrogen in paddy field are large. 展开更多
关键词 土壤肥力评价 地理信息系统 洞庭湖湿地 模糊评价方法 湿地面积 基础 湿地生态系统 综合评价指标体系
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Temporal Distribution of Fish Community Structure in Dongting Lake Estuary 被引量:1
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作者 Xiping Yuan Xin Yang +2 位作者 Hongzi Ge Hong Li Daqing Deng 《Agricultural Sciences》 2019年第3期294-301,共8页
The Dongting Lake Estuary is migration pathways for some river-lake migratory and semi-migratory fishes. In the present study, an annual survey of fish was conducted from January to November 2018 covering a total of 6... The Dongting Lake Estuary is migration pathways for some river-lake migratory and semi-migratory fishes. In the present study, an annual survey of fish was conducted from January to November 2018 covering a total of 6 sites in Dongting Lake Estuary. A total of 57 freshwater species and subspecies belonging to 5 orders and 10 families were recorded. The catches at the Dongting Lake Estuary were mainly composed of Lake settled fish. The biomass of Cyprinus (Cyprinus) carpio Linnaeus was the highest, accounting for 25.53% of the total catches, followed by Hypophthalmichthys molitrixs, Culter alburnus Basilewsky and Ctenopharyngodon idellus, accounting for 10.41%, 8.99% and 7.10% of the total catches, respectively. The four major domestic carps accounted for 26.13% of the total catch. The range of richness of species varied between 40 and 51 species. The trend was fewer species in spring, with the arrival of summer and autumn gradually increasing, peaking at the turn of summer and autumn, and then gradually decreasing with the arrival of winter, to the lowest in spring. The Shannon, Simpson, Pielou and Margalef indices showed the consistent trends with richness of species. 展开更多
关键词 BIODIVERSITY dongting lake ESTUARY FRESHWATER FISH
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Application of Bayesian regularized BP neural network model for analysis of aquatic ecological data—A case study of chlorophyll-a prediction in Nanzui water area of Dongting Lake 被引量:5
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作者 XU Min ZENG Guang-ming +3 位作者 XU Xin-yi HUANG Guo-he SUN Wei JIANG Xiao-yun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第6期946-952,共7页
Bayesian regularized BP neural network(BRBPNN) technique was applied in the chlorophyll-a prediction of Nanzui water area in Dongting Lake. Through BP network interpolation method, the input and output samples of the ... Bayesian regularized BP neural network(BRBPNN) technique was applied in the chlorophyll-a prediction of Nanzui water area in Dongting Lake. Through BP network interpolation method, the input and output samples of the network were obtained. After the selection of input variables using stepwise/multiple linear regression method in SPSS 11.0 software, the BRBPNN model was established between chlorophyll-a and environmental parameters, biological parameters. The achieved optimal network structure was 3-11-1 with the correlation coefficients and the mean square errors for the training set and the test set as 0.999 and 0.00078426, 0.981 and 0.0216 respectively. The sum of square weights between each input neuron and the hidden layer of optimal BRBPNN models of different structures indicated that the effect of individual input parameter on chlorophyll-a declined in the order of alga amount > secchi disc depth(SD) > electrical conductivity(EC). Additionally, it also demonstrated that the contributions of these three factors were the maximal for the change of chlorophyll-a concentration, total phosphorus(TP) and total nitrogen(TN) were the minimal. All the results showed that BRBPNN model was capable of automated regularization parameter selection and thus it may ensure the excellent generation ability and robustness. Thus, this study laid the foundation for the application of BRBPNN model in the analysis of aquatic ecological data(chlorophyll-a prediction) and the explanation about the effective eutrophication treatment measures for Nanzui water area in Dongting Lake. 展开更多
关键词 贝叶斯定理 人工神经网络 水体生态系统 叶绿素 洞庭湖 营养作用
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The spatial-temporal changes of the land use/cover in the Dongting Lake area during the last decade 被引量:4
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作者 LIRendong LIUJiyuan +1 位作者 ZHUANGDafang WANGHongzhi 《Journal of Geographical Sciences》 SCIE CSCD 2003年第3期259-264,共6页
The research on the land use/cover change is one of the frontiers and the hot spots in the global change research. Based on the Chinese resource and environment spatial-temporal database, and using the Landsat TM and ... The research on the land use/cover change is one of the frontiers and the hot spots in the global change research. Based on the Chinese resource and environment spatial-temporal database, and using the Landsat TM and ETM data of 1990 and 2000 respectively, we analyzed the spatial-temporal characteristics of land use/cover changes in the Dongting Lake area during the last decade. The result shows that during the last ten years there were three land-use types that had changed remarkably. The cultivated land decreased by 0.57% of the total cultivated land. The built-up land and water area expanded, with an increase of 8.97% and 0.43% respectively. The conversion between land use types mostly happened among these three land-use types, especially frequently between cultivated land and water area. The land-use change speed of land-use type is different. Three cities experienced the greatest degree of land-use change among all the administrative districts, which means that the land use in these cities changed much quickly. The following changed area was the west and south of the Dongting Lake area. The slowest changed area is the north and east area. 展开更多
关键词 空间-时间关系 遥感技术 洞庭湖 土地利用
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THE PRELIMINARY STUDY ON LANDSCAPE CULTURE ORIENTATION AND EXPLOITATION OF THE SOUTH DONGTING LAKE WETLAND 被引量:4
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作者 HEPing WANGBao-zhong 《Chinese Geographical Science》 SCIE CSCD 2002年第3期254-261,共8页
Dongting Lake is internationally a n important wetland.We studied and s ummarized the conception,func-tion,classification and current situation of the wetland-landscape cu lture in this region.The results showed that ... Dongting Lake is internationally a n important wetland.We studied and s ummarized the conception,func-tion,classification and current situation of the wetland-landscape cu lture in this region.The results showed that the cul-ture of Dongting Lake wetland was ric h in diversity,which are the Rice Cul tivation Culture,high-balustrade dwelling,Nuo Culture,Ship Culture,Dragon Bo at Culture,Chu Culture,Ancient Arc hitecture Landscape,Wetland Foodstuff and Cuisine Culture,Civil Art,Historic Heritage and Cultural Relics,Revolutionary Sites and Ruins,and Production and Living Culture,etc.We also evaluated the eco-tourism value of wetland l andscape culture,and analyzed its f eatures and orientation.The results revealed t hat the south Dongting Lake wetland p lays a key role on the Changjiang(Yangtze)River reaches civilization and Chinese civilization,even has great influence on the global civilization.We summ arized that the soul of the south Dongting Lake Cultu re was Wetland Culture,Water Cultur e,Rice Cultivation and Chu Culture.The thoughts,principles and approaches of sustainable exploitation and ut ilization of the wetland landscape c ulture were formulat-ed and suggested. 展开更多
关键词 洞庭湖 湿地景观 地形 地貌 环境旅游 湿地文化
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