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Oxygen and hydrogen isotope characteristics of different water bodies in the Burqin River Basin of the Altay Mountains,China
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作者 XIE Yida WANG Feiteng LIU Shuangshuang 《Journal of Arid Land》 SCIE CSCD 2024年第10期1365-1379,共15页
Characterization of the spatial and temporal variability of stable isotopes in surface water is essential for interpreting hydrological processes.In this study,we collected the water samples of river water,groundwater... Characterization of the spatial and temporal variability of stable isotopes in surface water is essential for interpreting hydrological processes.In this study,we collected the water samples of river water,groundwater,and reservoir water in the Burqin River Basin of the Altay Mountains,China in 2021,and characterized the oxygen and hydrogen isotope variations in different water bodies via instrumental analytics and modeling.Results showed significant seasonal variations in stable isotope ratios of oxygen and hydrogen(δ18O andδ2H,respectively)and significant differences inδ18O andδ2H among different water bodies.Higherδ18O andδ2H values were mainly found in river water,while groundwater and reservoir water had lower isotope ratios.River water and groundwater showed differentδ18O-δ2H relationships with the local meteoric water line,implying that river water and groundwater are controlled by evaporative enrichment and multi-source recharge processes.The evaporative enrichment experienced by reservoir water was less significant and largely influenced by topography,recharge sources,local moisture cycling,and anthropogenic factors.Higher deuterium excess(d-excess)value of 14.34‰for river water probably represented the isotopic signature of combined contributions from direct precipitation,snow and glacial meltwater,and groundwater recharge.The average annual d-excess values of groundwater(10.60‰)and reservoir water(11.49‰)were similar to the value of global precipitation(10.00‰).The findings contribute to understanding the hydroclimatic information reflected in the month-by-month variations in stable isotopes in different water bodies and provide a reference for the study of hydrological processes and climate change in the Altay Mountains,China. 展开更多
关键词 water bodies stable isotopes deuterium excess(d-excess) Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)model Burqin river Basin Altay Mountains
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Morphological Characteristics of Cambodia Mekong Delta and Tonle Sap Lake and Its Response to River-Lake Water Exchange Pattern 被引量:2
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作者 Zhaoming Xu Changwen Li +4 位作者 Anqiang Li Zhongqiong You Wei Yao Yongsheng Chen Liyao Huang 《Journal of Water Resource and Protection》 2020年第4期275-302,共28页
Tonle Sap Lake is the largest river-connected lake, buffer area and ecological zone of Mekong River, which plays a huge role in dispelling flood peak and compensating water, and the conservation of biological diversit... Tonle Sap Lake is the largest river-connected lake, buffer area and ecological zone of Mekong River, which plays a huge role in dispelling flood peak and compensating water, and the conservation of biological diversity. The river-lake relationship between Mekong River and Tonle Sap Lake is unique and has always been a major focus in the international community. The land terrain and under-water topography were used to analyze the morphological characteristics of Cambodia Mekong Delta and Tonle Sap Lake. Long series of hydrological data of river-lake controlling stations were used to analyze the water level variation characteristics and water volume exchange pattern between Mekong River and Tonle Sap Lake, and the response relationship to river-lake morphological characteristics were also researched. The results show that: Cambodia Mekong Delta and Tonle Sap Lake Area is low-lying and flat with gentle channel gradient and water surface gradient, making the relationship between water level and area (or volume) smooth. The channel storage capacity of Mekong River and Tonle Sap River is not enough compared to the inflow, so vast flooding plain is extremely prone to be inundated, making the flood relationships between the left and right banks become very complicated. Tonle Sap Lake is a seasonal freshwater lake with water flowing in and flowing out, and the timing and intensity of water exchange with Mekong River are closely related to the water flow resistance at the exit section of Tonle Sap Lake and the cross-sectional area of Tonle Sap River, which can be reflected by the river-lake water level difference and the water level of Tonle Sap River. Affected by the river-lake morphological characteristics, the water exchange intensity between Mekong River and Tonle Sap Lake is great. Tonle Sap Lake not only stores 14.4% of flood volume (39.7 billion m3) from the Mekong River every year, but also supplies 29.7% of dry water (69.4 billion m3) to the Mekong River. Influenced by the adjustment of the floodplain, the water level fluctuation of Mekong River and Tonle Sap Lake is slow, and the rising and droop rates of water level are positively correlated with the floodplain storage area. The research results will help to understand the relationship mechanism between Mekong River and Tonle Sap Lake and provide a scientific basis for the comprehensive governance of Cambodia Mekong Delta and Tonle Sap Lake Area. 展开更多
关键词 Tonle Sap lake Mekong river Morphological Characteristic river-lake RELATIONSHIP water EXCHANGE PATTERN RESPONSE RELATIONSHIP
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Diversity and Adaptations of Immature Diptera in Semiaquatic Habitats at Shorelines of Hypersaline Lakes in the Crimea,with a Brief Review of Diptera in Mineralized Bodies of Water
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作者 Andrey PRZHIBORO 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期98-100,共3页
The order Diptera(Insecta)is one of animal groups most successful in the colonization of mineralized shallow aquatic and semiaquatic environments.At the same time,the taxonomic composition of Diptera,their role in
关键词 salt lakes mineralized bodies of water aquatic habitats shoreline semiaquatic habitats DIPTERA larvae biodiversity community taxonomic richness ADAPTATIONS heat shock proteins.
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Characteristics and Effects of Inorganic Nitrogen in East Water-source and Inflow Rivers of Chaohu Lake
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作者 张习 曹静 +2 位作者 李琪 王宁 李玉成 《Agricultural Science & Technology》 CAS 2012年第4期877-882,共6页
[Objective] To study the characteristics and effects of inorganic nitrogen in east water-source and inflow rivers of Chaohu Lake. [Method] The speciation and distribution characteristics of dissolvable inorganic nitro... [Objective] To study the characteristics and effects of inorganic nitrogen in east water-source and inflow rivers of Chaohu Lake. [Method] The speciation and distribution characteristics of dissolvable inorganic nitrogen (DIN) in east water-source and inflow rivers of Chaohu Lake were investigated, and their effects on water qual- ity were examined. [Result] The concentrations of NH3-N and NO2--N were the high in flood season, and low in non-flood season, while the concentration of NO3--N pre- sented the opposite trend; the concentration of NO3--N was the highest in Shuangqiao estuary, where the pollution was the worst. DIN in Zhegao estuary and Xiaozhegao estuary was mainly caused by domestic sewage and industrial wastewaters; surface runoff and pollution from ships contribute the most to the DIN content in Shuangqiao estuary. [Conclusion] This study provided basic data and theoretical basis for the control and management of eutrophication in Chaohu Lake. 展开更多
关键词 Chaohu lake water source area Inflow rivers Inorganic nitrogen SPECIATION
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Relationship Between Changes of River-lake Networks and Water Levels in Typical Regions of Taihu Lake Basin,China 被引量:6
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作者 YIN Yixing XU Youpeng CHEN Ying 《Chinese Geographical Science》 SCIE CSCD 2012年第6期673-682,共10页
The typical regions of the Taihu Lake Basin,China,were selected to analyze the variation characteristics of river-lake networks under intensive human activities.The characteristics of the fractal dimension of river ne... The typical regions of the Taihu Lake Basin,China,were selected to analyze the variation characteristics of river-lake networks under intensive human activities.The characteristics of the fractal dimension of river networks and lakes for different periods were investigated and the influences of river system evolution on water level changes were further explored through the comparison of their fractal characters.The results are as follows:1) River network development of the study area is becoming more monotonous and more simple;the number of lakes is reducing significantly,and the water surface ratio has dropped significantly since the 1980s.2) The box dimension of the river networks in all the cities of the study area decreased slowly from the 1960s to the 1980s,while the decrease was significant from the 1980s to the 2000s.The variations of lake correlation dimension are similar to those of the river network box dimensions.This is unfavorable for the storage capacity of the river networks and lakes.3) The Hurst exponents of water levels were all between 0.5 and 1.0 from the 1960s to the 1980s,while decreased in the 2000s,indicating the decline in persistence and increase in the complexity of water level series.The paper draws a conclusion that the relationship between the fractal dimension of river-lake networks and the Hurst exponents of the water level series can reveal the impacts of river system changes on flood disasters to some extent:the disappearance of river networks and lakes will increase the possibility of flood occurrence. 展开更多
关键词 river network lake water level changes FRACTAL Taihu lake Basin
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Maintaining healthy rivers and lakes through water diversion from Yangtze River to Taihu Lake in Taihu Basin 被引量:4
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作者 Wu Haoyun Hu Yan 《Water Science and Engineering》 EI CAS 2008年第3期36-43,共8页
On the basis of the Taihu water resources assessment, an analysis of the importance and rationality of the water diversion from the Yangtz,e River to Taihu Lake in solving the water problem and establishing a harmonio... On the basis of the Taihu water resources assessment, an analysis of the importance and rationality of the water diversion from the Yangtz,e River to Taihu Lake in solving the water problem and establishing a harmonious eco-environment in the Taihu Basin is performed. The water quantity and water quality conjunctive dispatching 'decisi"ofi-makifig support system, which ensures flood control, water supply and eco-aimed dispatching, is built by combining the water diversion with flood control dispatching and strengthening water resources monitoring and forecasting. With the practice and effect assessment, measures such as setting the -integrated basin management format, further developing water diversion and improving the hydraulic engineering projects system and water monitoring system are proposed in order to maintain healthy rivers and guarantee the development of the economy and society in the Taihu Basin. 展开更多
关键词 Taihu Basin water resources distribution water diversion from the Yangtze river to Taihu lake healthy rivers and lakes
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Comparison and Selection of Water Restoration Techniques for Artificial Landscape Lakes in Nantong City
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作者 Shengrong YAN Yuyue MA +2 位作者 Yi'an CHEN Jiafeng SUN Mingqing CHEN 《Agricultural Biotechnology》 2024年第3期90-92,95,共4页
As an important part of urban infrastructure,urban water system is of great and far-reaching significance for ensuring urban flood control and waterlogging safety,protecting ecological environment and building livable... As an important part of urban infrastructure,urban water system is of great and far-reaching significance for ensuring urban flood control and waterlogging safety,protecting ecological environment and building livable homes.Taking the urban water system of Nantong as an example,Nantong Water Resources Bureau issued R evision of Nantong Urban Water System Planning in 2017,and put forward the construction of the"two circles,eight lakes and nine veins"water system layout,giving new vitality to the urban water system.In view of problems existing in newly excavated artificial landscape lakes,such as fragile water ecosystem,strong eutrophication trend,poor environmental sensory effect and unsatisfactory water landscape effect,it is urgent to study the in-situ water ecological restoration technique of"algae-controlling zooplankton+submerged plant community"to build a"grass-type clear water"ecosystem for artificial landscape lakes,so as to improve the water sensory index and self-purification ability and finally realize the double improvement of"sensory effect and water quality"of artificial landscape lakes. 展开更多
关键词 water body remediation technique Artificial landscape lake Comparison and selection Nantong City
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Evaluation on Current Situation of the Water Ecology of the Main Rivers and Lakes in the Liaohe River Basin 被引量:1
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作者 Jisheng WU Jun LV Tuanhao LIANG 《Meteorological and Environmental Research》 CAS 2020年第2期10-14,共5页
In this paper,15 rivers and 10 lake reservoirs in the Liaohe River basin were taken as research objects. Based on six indexes: satisfaction situation of ecological water demand,standard-reaching rate of water quality ... In this paper,15 rivers and 10 lake reservoirs in the Liaohe River basin were taken as research objects. Based on six indexes: satisfaction situation of ecological water demand,standard-reaching rate of water quality in water function area,eutrophication index of lakes and reservoirs,longitudinal connectivity of rivers,reserve rate of important wetlands and status of important aquatic habitat,water ecological conditions of main rivers and lakes in the basin were evaluated. The results showed that the rivers with better ecology were mainly distributed in east mountainous area of Liaoning,such as the upper reaches of the Hunhe River and the Taizi River;the problems of water pollution,ecological water shortage and habitat shrinkage were widespread in the Liaohe River basin,and the situation of water ecological security in the Liaohe River basin still faced great pressure. 展开更多
关键词 The Liaohe river BASIN MAIN riverS and lakeS EVALUATION on water ECOLOGY
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Relationship between Land Cover Changes with Water Quantity in Lake Victoria—A Case Study of Mara River Basin in Tanzania
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作者 Martine Hagai 《Journal of Environmental Science and Engineering(B)》 2018年第1期28-34,共7页
LV(Lake Victoria)is valuable to the East African sub region and Africa in general,sources of water for LV are from its catchment areas and tributaries e.g.Kagera and Mara Rivers on Tanzania part.Apparently,catchment a... LV(Lake Victoria)is valuable to the East African sub region and Africa in general,sources of water for LV are from its catchment areas and tributaries e.g.Kagera and Mara Rivers on Tanzania part.Apparently,catchment areas in proximities of LV and on MR(Mara River),indeed on MRB(Mara River Basin)in particular,are experiencing increased anthropogenic activities such as mining,fishing,settlements,agriculture etc.,which lead to increased water usage,land degradation and environmental pollution.Such activities threaten the sustainability of the environment surrounding MRB and impliedly LV and its ecosystem.The level of water in LV is reported to be declining threatening its extinction.This paper is reporting on a study undertaken to establish the relationship between land cover changes with ground water discharge from specifically MRB into LV over the period of 24 years,i.e.1986 to 2010.Methodology used is assessment of vegetation changes by using remote sensing through analysis of TM(Thematic Mapper)Landsat Images of 1986,1994,2002 and 2010 ETM(Enhanced Thematic Mapper)Landsat images,from which respective land cover change maps were generated and compared with ground water levels from MRB.Results indicates that there is a significant decline of land cover and ground water flowing into LV from MRB,and that there is positive correlation between land cover changes and the quantity of ground water flowing from MRB to LV.This phenomenon is common to all tributaries of LV,thus leading to decline of water in LV.It is recommended that relevant government institutions should endeavor formulating policies to control excessive use of wetlands and drylands in the proximity of LV and MRB in particular,such that the flow of water to LV may be sustained. 展开更多
关键词 Land COVER Changes Ground water Remote Sensing LV(lake Victoria) MRB(Mara river Basin)
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Morphological Difference and Karyotype of Pelteobagrus fulvidraco in Dongting Lake Water System 被引量:4
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作者 刘良国 邹万生 +2 位作者 杨春英 罗玉双 杨品红 《Agricultural Science & Technology》 CAS 2011年第10期1521-1524,共4页
[Objective] The research aimed to study the morphological characteristics and karyotype of Pelteobagrus fulvidraco in Dongting Lake water system.[Method] By using the conventional biological morphometry,PHA and colchi... [Objective] The research aimed to study the morphological characteristics and karyotype of Pelteobagrus fulvidraco in Dongting Lake water system.[Method] By using the conventional biological morphometry,PHA and colchicine injection method in vivo,the morphological characteristics and karyotype of P.fulvidraco in Yuanshui River and Lishui River of Dongting Lake were analyzed.[Result] In three ratio traits including standard length/head length,standard length/caudal peduncle depth,head length/snout length,P.fulvidraco of Yuanshui River and Lishui River had significant differences(P0.05).However,the number and karyotype of their chromosomes were same.The chromosome number was 2n = 52,and the karyotype formula was 20M+12SM+10ST+10T.The number of chromosome arm was 84.[Conclusion] The research result had certain theoretical guidance significance for the protection and utilization of wild P.resource in Dongting Lake water system. 展开更多
关键词 Dongting lake water system Yuanshui river and Lishui river P.fulvidraco Morphological characteristic KARYOTYPE
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Rare earth elements in tropical surface water,soil and sediments of the Terengganu River Basin,Malaysia 被引量:4
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作者 Khawar Sultan Noor Azhar Shazili 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第6期1072-1078,共7页
The 14 stable rare earth element(REE) concentrations and distribution patterns were investigated for surface waters(n=51),soils(n=52) and sediments(n=42) from the tropical Terengganu River basin,Malaysia.The chondrite... The 14 stable rare earth element(REE) concentrations and distribution patterns were investigated for surface waters(n=51),soils(n=52) and sediments(n=42) from the tropical Terengganu River basin,Malaysia.The chondrite normalized REE patterns of soils developed on four geological units showed enrichment of LREE,a pronounced negative Eu,and depletion of HREE with an enrichment order granite>>metasedimentary>alluvium>volcanic.The REE patterns in sediments reflected the soil REE patterns with an ove... 展开更多
关键词 rare earth elements river/lake water SOIL sediment MALAYSIA
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Water Quality Assessment of the River Nile System:An Overview 被引量:4
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作者 RIFAAT A.WAHAAB MOHAMED I.BADAWY 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2004年第1期87-100,共14页
Objectives The main objective of the present article is to assess and evaluate the characteristics of the Nile water system , and identify the major sources of pollution and its environmental and health consequences. ... Objectives The main objective of the present article is to assess and evaluate the characteristics of the Nile water system , and identify the major sources of pollution and its environmental and health consequences. The article is also aimed to highlight the importance of water management via re-use and recycle of treated effluents for industrial purpose and for cultivation of desert land. Method An intensive effort was made by the authors to collect, assess and compile the available data about the River Nile. Physico-chemical analyses were conducted to check the validity of the collected data. For the determination of micro-pollutants, Gas Chromatography (GC) and High Performance Liquid Chromatography (HPLC) were used. Heavy metals were also determined to investigate the level of industrial pollution in the river system. Results The available data revealed that the river receives a large quantity of industrial, agriculture and domestic wastewater. It is worth mentioning that the river is still able to recover in virtually all the locations, with very little exception. This is due to the high dilution ratio. The collected data confirmed the presence of high concentrations of chromium and manganese in all sediment samples. The residues of organo-chlorine insecticides were detected in virtually all locations. However, the levels of such residues are usually below the limit set by the WHO for use as drinking water. The most polluted lakes are Lake Maryut and Lake Manzala. Groundwater pollution is closely related to adjacent (polluted) surface waters. High concentrations of nutrients, E.coli, sulfur, heavy metals, etc. have been observed in the shallow groundwater, largely surpassing WHO standards for drinking water use. Conclusion A regular and continuous monitoring scheme shall be developed for the River Nile system. The environmental law shall be enforced to prohibit the discharge of wastewater (agricultural, domestic or industrial) to River Nile system. 展开更多
关键词 water quality river Nile lakeS Pollution sources ASSESSMENT
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Sediment transport following water transfer from Yangtze River to Taihu Basin 被引量:2
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作者 Zheng GONG Chang-kuan ZHANG +1 位作者 Cheng-biao ZUO Wei-deng WU 《Water Science and Engineering》 EI CAS 2011年第4期431-444,共14页
To meet the increasing :need of fresh water and to improve the water quality of Taihu Lake, water transfer from the Yangtze River was initiated in 2002. This study was performed to investigate the sediment distributi... To meet the increasing :need of fresh water and to improve the water quality of Taihu Lake, water transfer from the Yangtze River was initiated in 2002. This study was performed to investigate the sediment distribution along the river course following water transfer. A rainfall-runoff model was first built to calculate the runoff of the Taihu Basin in 2003. Then, the flow patterns of river networks were simulated using a one-dimensional river network hydrodynamic model. Based on the boundary conditions of the flow in tributaries of the Wangyu River and the water level in Taihu Lake, a one-dimensional hydrodynamic and sediment transport numerical model of the Wangyu River was built to analyze the influences of the inflow rate of the water transfer and the suspended sediment concentration (SSC) of inflow on the sediment transport. The results show that the water transfer inflow rate and SSC of inflow have significant effects on the sediment distribution. The higher the inflow rate or SSC of inflow is, the higher the SSC value is at certain cross-sections along the :river course of water transfer. Higher inflow rate and SSC of inflow contribute to higher sediment deposition per kilometer and sediment thickness. It is also concluded that a sharp decrease of the inflow velocity at the entrance of the Wangyu River on the river course of water transfer induces intense sedimentation at the cross-section near the Changshu hydro-junction. With an increasing distance from the Changshu hydro-junction, the sediment deposition and sedimentation thickness decrease gradually along the river course. 展开更多
关键词 Taihu Basin Taihu lake river network water transfer rainfall-runoff model 1-D hydrodynamic numerical model cohesive sediment
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Formation and water environmental evolution of the Nansihu Lake 被引量:1
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作者 ZHANGZulu SHENJi +2 位作者 LIUEnfeng SUNQingyi JIANGLuguang 《Journal of Geographical Sciences》 SCIE CSCD 2003年第2期241-249,共9页
Through high-resolution research of sedimental chronology and the sediment environmental indexes, such as graininess, minerals, magnetic parameters, pigment content, organic carbon and chronology in Ds-co... Through high-resolution research of sedimental chronology and the sediment environmental indexes, such as graininess, minerals, magnetic parameters, pigment content, organic carbon and chronology in Ds-core and Ws-core in Nansihu Lake, the authors analyze the formation cause of the Nansihu Lake and its water environmental changes. Historical documents are also analyzed here in order to reach the conclusion. Researches indicate that the Nansihu Lake came into being about 2500 aBP and its evolution succession can be divided into four stages. In this evolution process, several scattered lakes merge into one large lake in the east of China. This process is distinctively affected by the overflow of the Yellow River, the excavation of the Grand Canal and other human activities. 展开更多
关键词 Nansihu lake lake sediment study water environment evolution migration and overflow of the Yellow river excavation of the Grand Canal CLC number:X144
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Evaluation of the water conservation function in the Ili River Delta of Central Asia based on the InVEST model 被引量:2
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作者 CAO Yijie MA Yonggang +2 位作者 BAO Anming CHANG Cun LIU Tie 《Journal of Arid Land》 SCIE CSCD 2023年第12期1455-1473,共19页
The Ili River Delta(IRD)is an ecological security barrier for the Lake Balkhash and an important water conservation area in Central Asia.In this study,we selected the IRD as a typical research area,and simulated the w... The Ili River Delta(IRD)is an ecological security barrier for the Lake Balkhash and an important water conservation area in Central Asia.In this study,we selected the IRD as a typical research area,and simulated the water yield and water conservation from 1975 to 2020 using the water yield module of the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model.We further analyzed the temporal and spatial variations in the water yield and water conservation in the IRD from 1975 to 2020,and investigated the main driving factors(precipitation,potential evapotranspiration,land use/land cover change,and inflow from the Ili River)of the water conservation variation based on the linear regression,piecewise linear regression,and Pearson's correlation coefficient analyses.The results indicated that from 1975 to 2020,the water yield and water conservation in the IRD showed a decreasing trend,and the spatial distribution pattern was"high in the east and low in the west";overall,the water conservation of all land use types decreased slightly.The water conservation volume of grassland was the most reduced,although the area of grassland increased owing to the increased inflow from the Ili River.At the same time,the increased inflow has led to the expansion of wetland areas,the improvement of vegetation growth,and the increase of regional evapotranspiration,thus resulting in an overall reduction in the water conservation.The water conservation depth and precipitation had similar spatial distribution patterns;the change in climate factors was the main reason for the decline in the water conservation function in the delta.The reservoir in the upper reaches of the IRD regulated runoff into the Lake Balkhash,promoted vegetation restoration,and had a positive effect on the water conservation;however,this positive effect cannot offset the negative effect of enhanced evapotranspiration.These results provide a reference for the rational allocation of water resources and ecosystem protection in the IRD. 展开更多
关键词 water conservation function water yield Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model climate change land use/land cover change(LUCC) Ili river Delta lake Balkhash
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Extracting water body data based on SDWI and threshold segmentation:A case study in permafrost area surrounding Salt Lake in Hoh Xil,Qinghai-Tibet Plateau,China 被引量:1
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作者 QingSong Du GuoYu Li +4 位作者 Dun Chen ShunShun Qi Yu Zhou Fei Wang YaPeng Cao 《Research in Cold and Arid Regions》 CSCD 2023年第4期202-209,共8页
There are a large number of lakes,rivers,and other natural water bodies distributed in the permafrost area of the Qinghai-Tibet Plateau(QTP).The changes in water bodies will affect the distribution of water resources ... There are a large number of lakes,rivers,and other natural water bodies distributed in the permafrost area of the Qinghai-Tibet Plateau(QTP).The changes in water bodies will affect the distribution of water resources in sur-rounding areas and downstream areas,resulting in environmental impact and bringing potential flood disasters,which will induce more serious issues and problems in alpine and high-altitude areas with a fragile habitat(such as the QTP in China).Generally,effective,reasonable,and scientific monitoring of large-scale water bodies can not only document the changes in water bodies intuitively,but also provide important theoretical reference for subsequent environmental impact prediction,and disaster prevention and mitigation in due course of time.The large-scale water extraction technology derived from the optical remote sensing(RS)image is seriously affected by clouds,bringing about large differences among the extracted water result products.Synthetic aperture radar(SAR)RS technology has the unique advantage characteristics of all-weather,all-day,strong penetration,and not being affected by clouds,which is hopeful in extracting water body data,especially for days with cloudy weather.The data extraction of large-scale water bodies based on SAR images can effectively avoid the errors caused by clouds that become prevalent at present.In this paper,the Hoh Xil Salt Lake on the QTP and its surrounding five lakes are taken as the research objects.The 2-scene Sentinel-1 SAR image data covering the whole area on 22 August 2022 was used to verify the feasibility of extracting water body data in permafrost zones.Furthermore,on 22 August 2022,the wealth here was cloudy,which made the optical RS images,e.g.,Sentinel-2 images full of clouds.The results show that:using the Sentinel-1 image and threshold segmentation method to extract water body data is efficient and effective with excellent results in permafrost areas.Concretely,the Sentinel-1 dual-polarized water index(SDWI),calculated by combining dual vertical–vertical(VV)polarized and verti-cal–horizontal(VH)polarized data is a useful index for water extraction and the result is better than each of the VV or VH polarized images. 展开更多
关键词 Permafrost region water body extraction Salt lake in Hoh Xil Qinghai-Tibet Plateau Sentinel-1 Ecological environment impact Disaster prevention and mitigation
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Characteristics of Salt Water Movement in Iwaki River Estuary, Japan
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作者 Mikio Sasaki Hitoshi Tanaka Makoto Umeda 《Journal of Earth Science and Engineering》 2017年第1期10-19,共10页
The present study aims to investigate the characteristics of the motion of salt water and to show the temporal fluctuation of the vertical salinity distribution in Lake Jusan located in the estuary of Iwaki River in A... The present study aims to investigate the characteristics of the motion of salt water and to show the temporal fluctuation of the vertical salinity distribution in Lake Jusan located in the estuary of Iwaki River in Aomori Prefecture, Japan. The Lake Jusan is the best productive water area of the shellfish, corbicula, in Japan in 2013. Then, the lake is very important in Aomori Prefecture as corbicula's home. The change of the brackish environment influences the ecology of the corbicula shellfish, then, the shellfish harvest changes every year. Now, it is important to make clear the characteristics of the motion of salt water in the lake. In the present study, observations for the motion of the salt water going up to the lake and going down from the lake to the sea were carried out from June to September in 2015. The present study investigates the time change of the salinity distribution in a perpendicular direction and shows that the movement of the saltwater in the lake can be generated well by the theory given by Sasaki et al., 2009. 展开更多
关键词 ESTUARY river mouth brackish water saltwater stratified flow salt wedge Iwaki river lake Jusan.
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Distinguishing different subclasses of water bodies for long-term and large-scale statistics of lakes:a case study of the Yangtze River basin from 2008 to 2018
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作者 Jin Luo Zeqiang Chen Nengcheng Chen 《International Journal of Digital Earth》 SCIE 2021年第2期202-230,共29页
Long-term and large-scale lake statistics are meaningful for the study of environment change,but many of the existing methods are labourintensive and time-consuming.To overcome this problem,a novel method for long-te... Long-term and large-scale lake statistics are meaningful for the study of environment change,but many of the existing methods are labourintensive and time-consuming.To overcome this problem,a novel method for long-term and large-scale lake extraction by shape-factorsand machine-learning-based water body classification is proposed.An experiment was conducted to extract the lakes in the Yangtze River basin(YRB)from 2008 to 2018 with the Joint Research Centre’s Global Surface Water Dataset(JRC GSW)data and OSM data.The results show:1)The proposed method is automatically and successfully executed.2)The number of river–lake complexes is between 3008 and 4697,representing 3.56%–5.70%of the total water bodies.3)The areas of the lakes and rivers in the YRB were obtained,and the accuracy of water classification in each year was stable between 90.2%and 93.6%.Comparing the back propagation neural network,random forest,and support vector machine models,we found that the three machine learning models have similar classification accuracy for the scenario.4)Fragmented and incomplete small rivers in the JRC GSW data,unchecked training samples,and overlapped shape factors are the three error sources.Future work will focus on addressing these three error sources. 展开更多
关键词 lake extraction water bodies classification the Yangtze river shape metrics machine learning
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Climate effects on an inland alpine lake in Xinjiang, China over the past 40 years 被引量:7
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作者 HuiXia CHAI WeiMing CHENG +2 位作者 ChengHu ZHOU ShangMin ZHAO HaiJiang LIU 《Journal of Arid Land》 SCIE CSCD 2013年第2期188-198,共11页
Inland lakes are important water resources in arid and semiarid regions. Understanding climate effects on these lakes is critical to accurately evaluate the dynamic changes of water resources. This study focused on th... Inland lakes are important water resources in arid and semiarid regions. Understanding climate effects on these lakes is critical to accurately evaluate the dynamic changes of water resources. This study focused on the changes in Sayram Lake of Xinjiang, China, and addressed the effects of climate fluctuations on the inland lake based on long-term sequenced remote sensing images and meteorological data from the past 40 years. A geo- graphic information system (GIS) method was used to obtain the hypsometry of the basin area of Sayram Lake, and estimation methods for evaporation from rising temperature and water levels from increasing precipitation were proposed. Results showed that: (1)Areal values of Sayram Lake have increased over the past 40 years. (2) Both temperature and precipitation have increased with average increases of more than 1.8~C and 82 mm, respectively. Variation of the water levels in the lake was consistent with local climate changes, and the areal values show linear relationships with local temperature and precipitation data. (3) According to the hypsometry data of the basin area, the estimated lake water levels increased by 2.8 m, and the water volume increased by 12.9×108 m3 over the past 40 years. The increasing area of Sayram Lake correlated with local and regional climatic changes because it is hardly affected by human activities. 展开更多
关键词 Sayram lake climate change water body extraction areal variation inland alpine lake
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Analysis of the distribution characteristics of ^(226)Ra and ^(228)Ra and their sources in the western part of Qinghai Lake 被引量:3
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作者 孔凡翠 沙占江 +5 位作者 杜金洲 苏维刚 于晨光 赵顺利 胡菊芳 冶梅 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第6期1402-1412,共11页
The ^226Ra and ^228Ra activities of Qinghai Lake surface water, groundwater, river water, suspended particles, and bottom sediments were measured in a gamma-ray spectrometer. The sources of ^226Ra and ^228Ra were disc... The ^226Ra and ^228Ra activities of Qinghai Lake surface water, groundwater, river water, suspended particles, and bottom sediments were measured in a gamma-ray spectrometer. The sources of ^226Ra and ^228Ra were discussed according to their distribution characteristics. ^226Ra and ^228Ra activities (dpm/(100 L)) ranged from 14.13±0.22 to 19.22±0.42 and 17.724-0.66 to 30.96:kl.47 in the surface water of the North Bay, respectively, and from 7.88±0.24 to 33.80±0.47 and 15.73±0.74 to 57.31±1.44, respectively, in the South Bay. The surface water near the estuary had a lower salinity and had a higher concentration of radium isotopes than the samples collected further away. The farther offshore the sample, the higher the salinity was, and the lower the radium isotope activity. The distribution of radium activities in the western part of Qinghai Lake is controlled by several factors, including Buha River runoff, desorption from suspended particles derived from the river, groundwater discharge, and a small amount of diffusion from the sediment. 展开更多
关键词 ^226RA ^228Ra surface water of Qinghai lake groundwater river water Qinghai lake
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