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Flooding(or breaching)of inter-connected proglacial lakes by cascading overflow in the arid region of Western Mongolia(Mt.Tsambagarav,Mongolian Altai)
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作者 Otgonbayar DEMBEREL Chinmay DASH +6 位作者 Battsetseg DUGERSUREN Munkhbat BAYARMAA Yeong Bae SEONG Elora CHAKRABORTY Batsuren DORJSUREN Atul SINGH Nemekhbayar GANHUYAG 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3215-3233,共19页
This study investigates the glacial lake outburst flood(GLOF)hazards in the Tsambagarav mountain range in Western Mongolia,focusing on the Khukhnuruu Valley and its interconnected proglacial lakes.Over the last 30 yea... This study investigates the glacial lake outburst flood(GLOF)hazards in the Tsambagarav mountain range in Western Mongolia,focusing on the Khukhnuruu Valley and its interconnected proglacial lakes.Over the last 30 years,significant glacier retreats,driven by rising temperatures and changing precipitation patterns,have led to the formation and expansion of several proglacial lakes.Fieldwork combined with satellite data and meteorological analysis was used to assess the dynamics of glacier and lake area changes,with particular focus on the flood events of July 2021.The research reveals a substantial reduction in glacier area,particularly in the Khukhnuruu E complex,where glacier area decreased by 19.3%.The study highlights the influence of increasing temperatures and summer precipitation,which have accelerated ice melt,contributing to the expansion and eventual breaching of lakes.Additionally,lake area changes were influenced by the steepness of the terrain,with steeper slopes exacerbating peak discharge during floods.Of the studied seven lakes(Lake 1 to Lake 7),Lake 1 experienced the most dramatic reduction,with a decrease in area by 73.51%and volume by 84.84%,followed by Lake 7.This study underscores the region's vulnerability to climate-induced hazards and stresses the need for a comprehensive early warning system and disaster preparedness measures to mitigate future risks. 展开更多
关键词 Glacial lake outburst flood(GLOF) Mongolian Altai Climate change Proglacial lakes
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Glacier area change (1993-2019) and its relationship to debris cover, proglacial lakes, and morphological parameters in the Chandra-Bhaga Basin, Western Himalaya, India
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作者 VATSAL Sarvagya AZAM Mohd Farooq +5 位作者 BHARDWAJ Anshuman MANDAL Arindan BAHUGUNA Ishmohan RAMANATHAN Alagappan RAJU N.Janardhana TOMAR Sangita Singh 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1287-1306,共20页
Glacier inventories serve as critical baseline data for understanding the impacts of climate change on glaciers.The present study maps the outlines of glaciers in the Chandra-Bhaga Basin(western Himalaya)for the years... Glacier inventories serve as critical baseline data for understanding the impacts of climate change on glaciers.The present study maps the outlines of glaciers in the Chandra-Bhaga Basin(western Himalaya)for the years 1993,2000,2010,and 2019 using Landsat Thematic Mapper(TM),Enhanced Thematic Mapper(ETM),and Operational Land Imager(OLI)datasets.A total of 251 glaciers,each having an area above 0.5 km^(2),were identified,which include 216 clean-ice and 35 debris-covered glaciers.Area changes are estimated for three periods:1993-2000,2000-2010,and 2010-2019.The total glacierized area was 996±62 km^(2) in 1993,which decreased to 973±70 km^(2) in 2019.The mean rate of glacier area loss was higher in the recent decade(2010-2019),at 0.036 km^(2),compared to previous decades(0.029 km^(2) in 2000-2010 and 0.025 km^(2) in 1993-2000).Supraglacial debris cover changes are also mapped over the period of 1993 and 2019.It is found that the supraglacial debris cover increased by 14.12±2.54 km^(2)(15.2%)during 1993-2019.Extensive field surveys on Chhota Shigri,Panchi II,Patsio,Hamtah,Mulkila,and Yoche Lungpa glaciers were carried out to validate the glacier outlines and supraglacial debris cover estimated using satellite datasets.Controls of various morphological parameters on retreat were also analyzed.It is observed that small,clean ice,south oriented glaciers,and glaciers with proglacial lakes are losing area at faster rates than other glaciers in the basin. 展开更多
关键词 GLACIER Area change Debris cover MORPHOLOGY Proglacial lake
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Morphology of crater and caldera lakes in the Far Eastern region of Russia and the features of their development
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作者 Dmitrii N.KOZLOV Ekaterina V.LEBEDEVA 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1246-1258,共13页
Volcanic lakes in the Kuril-Kamchatka region are difficult to access,and for this reason,they remain poorly studied,with only scattered and brief data available.The authors have conducted a study of 10 lake basins usi... Volcanic lakes in the Kuril-Kamchatka region are difficult to access,and for this reason,they remain poorly studied,with only scattered and brief data available.The authors have conducted a study of 10 lake basins using modern digital echolocation survey techniques and have also compiled and summarized published data for 15 lakes in the region,calculating their main morphometric characteristics.It has been established that many caldera lake basins are modified by young explosive funnels,extrusive or effusive domes,and exhibit traces of hydrothermal activity.While lakes of the same genetic type in the Kuril-Kamchatka region are similar in depth and depression forms,the group of caldera lakes shows less homogeneity across all morphometric indicators.It was found that the absolute heights of the reservoirs on Kamchatka Peninsula are generally greater than those on the Kuril Islands,as is often the case with the size of their basins.The volcanic lakes under study can rapidly change their volume and shape under the influence of endogenous processes.For the first time for this region,on the base of repeated observations,underwater extrusive dome rate growth and the approximate rates of 2 lake level changes were calculated.Repeated observations of lakes in the Ksudach calderas(Kamchatka)and on Simushir Island indicate approximate rates of level changes:a decrease ranging within 0.5-0.6 m per year(over a 27-year observation interval)and an increase reaching up to 0.26 m per year(over a 48-year interval).The growth rate of the underwater extrusive dome in Lake Shtyubel has averaged 1-1.6 m per year over the past 25 years.This analysis has facilitated the first generalization regarding the morphology and developmental features of crater and caldera lakes in the Kuril-Kamchatka region of Russia,representing an important step in their study.The results obtained will provide a solid foundation for subsequent research in this region and may be of interest to researchers studying other volcanic lakes. 展开更多
关键词 Volcanic lakes Echolocation survey VOLCANISM Gashydrotherms KAMCHATKA Kuril Islands
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Quantifying freeze-melt dynamics of lakes on the Tibetan Plateau using Sentinel-1 synthetic aperture radar imagery
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作者 JIN Lu CHEN Jun +3 位作者 CAI Yu KONG Yecheng WANG Yongfeng DUAN Zheng 《Journal of Mountain Science》 SCIE CSCD 2024年第3期805-819,共15页
The ice phenology of alpine lakes on the Tibetan Plateau(TP)is a rapid and direct responder to climate changes,and the variations in lake ice exhibit high temporal frequency characteristics.MODIS and passive microwave... The ice phenology of alpine lakes on the Tibetan Plateau(TP)is a rapid and direct responder to climate changes,and the variations in lake ice exhibit high temporal frequency characteristics.MODIS and passive microwave data are widely used to monitor lake ice changes with high temporal resolution.However,the low spatial resolutions make it difficult to effectively quantify the freeze-melt dynamics of lakes.This work used Sentinel-1 synthetic aperture radar(SAR)data to derive high-resolution ice maps(about 6 days),then with the aid of Sentinel-2 optical images to quantify freeze-melt processes in three typical lakes on the TP(e.g.Selin Co,Ayakekumu Lake,and Nam Co).The results showed that three lakes had an average annual ice period of 125-157 days and a complete ice cover period of 72-115 days,from 2018 to 2022.They exhibit different ice phenology patterns.Nam Co is characterized by repeated episodes of freezing,melting,and refreezing,resulting in a prolonged freeze-up period.Meanwhile,the break-up period of Nam Co lasts for a longer duration(about 19 days),and the break-up exhibits a smooth process.Similarly,Ayakekumu Lake showed more significant inter-annual fluctuations in the freeze-up period,with deviations of up to 28 days observed among different years.Compared to the other two lakes,Selin Co experienced a relatively short freeze-up and break-up period.In short,Sentinel-1 SAR data can effectively monitor the weekly and seasonal variations in lake ice on the TP.Particularly,this data facilitates quantification of the freeze-melt dynamics. 展开更多
关键词 lake ice Sentinel-1 SAR Tibetan Plateau Climate change
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Shallow sub-lakes are essential for sustaining the successful wintering of waterbirds in Poyang Lake,China
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作者 Mengjie Lu Zhen Zhang +3 位作者 Peng Chen Changxin Xu Bin Gao Luzhang Ruan 《Avian Research》 SCIE CSCD 2024年第2期219-228,共10页
For migratory waterbirds,the quality of wintering habitat is related to spring migration and successful breeding in the next year.The availability of food resources in the habitat is critical and varies within water l... For migratory waterbirds,the quality of wintering habitat is related to spring migration and successful breeding in the next year.The availability of food resources in the habitat is critical and varies within water levels.Although the water-level fluctuations in Poyang Lake have been extremely variable interannually in recent years,the wintering waterbird populations have remained relatively stable.Hence,the mechanism of maintaining the stability is worth exploring.This study aimed to compare the distribution of vegetation and herbivorous wa-terbirds in 2015-2016 and 2016-2017,focusing on three shallow sub-lakes and one main lake are.The results showed that the emergence of tubers and the growth of Carex spp.provided a continuous food supply and habitat for wintering waterbirds with a gradual decline in the water level.Shallow sub-lakes supported almost all of the tuber-eating waterbirds(1.42-1.62×10^(5))and most geese(1.34-1.53×10^(6)).However,the main lake area,covered with Persicaria hydropiper,did not provide adequate and accessible food.This resulted in almost no distribution of tuber-eating waterbirds,with only a few geese congregating in early winter.Our results demonstrated that the shallow sub-lakes under human control provided a different environment from the main lake and are key to sustaining the successful wintering of hundreds of thousands of migratory waterbirds in Poyang Lake.Therefore,we recommend refining the anthropogenic management of the shallow sub-lakes to regulate the water level to ensure the carrying capacity of Poyang Lake. 展开更多
关键词 Anthropogenic management Carrying capacity Seasonal lake Water level Wintering habitat
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Assessment of rehabilitation strategies for lakes affected by anthropogenic and climatic changes: A case study of the Urmia Lake, Iran
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作者 Seyed Morteza MOUSAVI Hossein BABAZADEH +1 位作者 Mahdi SARAI-TABRIZI Amir KHOSROJERDI 《Journal of Arid Land》 SCIE CSCD 2024年第6期752-767,共16页
Over the last three decades,more than half of the world's large lakes and wetlands have experienced significant shrinkage,primarily due to climate change and extensive water consumption for agriculture and other h... Over the last three decades,more than half of the world's large lakes and wetlands have experienced significant shrinkage,primarily due to climate change and extensive water consumption for agriculture and other human needs.The desiccation of lakes leads to severe environmental,economic,and social repercussions.Urmia Lake,located in northwestern Iran and representing a vital natural ecosystem,has experienced a volume reduction of over 90.0%.Our research evaluated diverse water management strategies within the Urmia Lake basin and prospects of inter-basin water transfers.This study focused on strategies to safeguard the environmental water rights of the Urmia Lake by utilizing the modeling and simulating(MODSIM)model.The model simulated changes in the lake's water volume under various scenarios.These included diverting water from incoming rivers,cutting agricultural water use by 40.0%,releasing dam water in non-agricultural seasons,treated wastewater utilization,and inter-basin transfers.Analytical hierarchy process(AHP)was utilized to analyze the simulation results.Expert opinions with AHP analysis,acted as a multi-criteria decision-making tool to evaluate the simulation and determine the optimal water supply source priority for the Urmia Lake.Our findings underscore the critical importance of reducing agricultural water consumption as the foremost step in preserving the lake.Following this,inter-basin water transfers are suggested,with a detailed consideration of the inherent challenges and limitations faced by the source watersheds.It is imperative to conduct assessments on the impacts of these transfers on the downstream users and the potential environmental risks,advocating for a diplomatic and cooperative approach with adjacent country.This study also aims to forecast the volumes of water that can be transferred under different climatic conditions—drought,normal,and wet years—to inform strategic water management planning for the Urmia Lake.According to our projection,implementing the strategic scenarios outlined could significantly augment the lake's level and volume,potentially by 3.57×109–9.38×109 m3 over the coming 10 a and 3.57×109–10.70×109 m3 in the subsequent 15 a. 展开更多
关键词 climate change DROUGHT lake ecological level agricultural water demand inter-basin water transfer
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Microscopic analysis on eukaryotic algae and cyanobacteria in nine seasonal lakes and ponds in Vestfjella,Dronning Maud Land,Antarctica
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作者 Lauri ARVOLA Matti LEPPÄRANTA LI Zhijun 《Advances in Polar Science》 CSCD 2024年第2期206-218,共13页
Antarctic continental lakes and ponds are among the most impoverished aquatic environments on earth but many of them support flourishing populations of cyanobacteria,eukaryotic algae,protozoans,and some multicellular ... Antarctic continental lakes and ponds are among the most impoverished aquatic environments on earth but many of them support flourishing populations of cyanobacteria,eukaryotic algae,protozoans,and some multicellular animals.In this study,we present results of a microscopic analysis of cyanobacteria and eukaryotic algae from nine diverse types of Antarctic continental water bodies during one austral summer.The results supplement and enlarge our previous studies on the limnological characteristics of the epiglacial and supraglacial lakes and ponds in Dronning Maud Land,an area that has received little attention from limnologists.The taxon with highest frequency among the samples(n=79)was Mesotaenium cf.berggrenii,a eukaryotic Zygnematophyceae,which occurred in 82%of the samples with a maximum cell density of 68 cells·mL^(-1).The taxa with second and third highest frequency were the prokaryotes Gloeocapsopsis(60%)and Leptolyngbya(41%),followed by Chlamydomonas(34%)and Cyanothece(29%).The number of taxa varied between 7-21 among the lakes and ponds,being highest in a supraglacial lake,and lowest in an epiglacial lake.The results did not reveal any obvious correlation between the abundance of any taxa and the water chemistry,but water bodies with inorganic sediments had higher cell densities and biomasses than those without sediment.This suggests the importance of sediment in supporting biological diversity in these ultraoligotrophic lakes and ponds. 展开更多
关键词 Antarctic continental lakes Antarctic continental ponds CYANOBACTERIA algae protozoa rotifers TARDIGRADA
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Glacial lakes under climate change: the imperative for comparative studies of microbial carbon metabolism in the Qinghai-Xizang Plateau and the Arctic
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作者 LIU Keshao LIU Yongqin 《Advances in Polar Science》 CSCD 2024年第3期324-326,共3页
Glacial lakes,intimately linked to glacier termini,are crucial landscape features of the Qinghai-Xizang Plateau(QXP,Qinghai-Tibet Plateau)and the Arctic.Climate warming has accelerated glacier retreat and the rapid ex... Glacial lakes,intimately linked to glacier termini,are crucial landscape features of the Qinghai-Xizang Plateau(QXP,Qinghai-Tibet Plateau)and the Arctic.Climate warming has accelerated glacier retreat and the rapid expansion of glacial lakes in both regions.Despite being typically considered harsh environments,these lakes serve as vital reservoirs for microbial biodiversity and carbon metabolism.In the face of climate change,glacial lake ecosystems over the QXP and the Arctic are undergoing unprecedentedtransformations.Thisopinioneditorial highlights the significance of conducting research and establishing long-term monitoring programs focused on microbial carbon metabolism in these glacial lakes. 展开更多
关键词 glacial lakes Qinghai-Xizang Plateau ARCTIC microbial carbon metabolism climate change glacier retreat
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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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Ecological Restoration Technologies of Urban Artificial Landscape Lakes
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作者 Yuyue MA Shengrong YAN +2 位作者 Yi'an CHEN Jiafeng SUN Mingqing CHEN 《Meteorological and Environmental Research》 2024年第3期21-22,31,共3页
Aiming at the problems of water pollution and ecological environment degradation in urban artificial landscape lakes,the ecological restoration technologies of artificial landscape lakes at home and abroad were studie... Aiming at the problems of water pollution and ecological environment degradation in urban artificial landscape lakes,the ecological restoration technologies of artificial landscape lakes at home and abroad were studied to provide some reference for the ecological restoration of urban artificial landscape lakes in China. 展开更多
关键词 Artificial landscape lake Ecological restoration technology CITY
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Hydrochemistry of the lakes in the southern Badain Jaran Desert and its paleosalinity reconstruction
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作者 Gao-lei Jiang Zhe Wang +4 位作者 Zhen-long Nie Zhong-shuang Cheng Pu-cheng Zhu Le Cao Jian-mei Shen 《China Geology》 CAS CSCD 2024年第4期642-652,共11页
The reconstruction of paleohydrology,especially paleosalinity,is an important component of paleoenvironmental research.Researches on the modern characteristics of lake water chemistry and the relationship between lake... The reconstruction of paleohydrology,especially paleosalinity,is an important component of paleoenvironmental research.Researches on the modern characteristics of lake water chemistry and the relationship between lake salinity and hydrochemistry are the basis of paleoenvironment reconstruction.The modern hydrochemical characteristics and the relationship between ion composition and salinity of modern lakes are the basis of paleosalinity reconstruction.In this study,hydrochemical analysis of 21 lakes in the Badain Jaran Desert(BJD)was carried out.The relationships between the Sr/Ca and Mg/Ca ratios and total dissolved solids(TDS)were analyzed.The results show that Na^(+),K^(+),Cl-and SO_(4)^(2-)have high positive correlations with TDS,and Mg^(2+),Sr^(2+),CO_(3)_(2-)and HCO_(3)^(-)have lower correlations with TDS.The Sr/Ca and Mg/Ca ratios do not increase linearly with TDS.Hydrochemical analysis indicates that the studied lakes are in the carbonate precipitation stage and that evaporation is the main factor controlling lake evolution in the BJD.The relationships between the Mg/Ca and Sr/Ca ratios and TDS are mainly influenced by lake evolution stage and the hydrochemical types of the lakes.On the basis of comprehensive previous studies,the factors affecting lake evolution,the Mg and Sr partition coefficients and other hydrochemical parameters that change with lake evolution all affect the relationship between chemical composition and salinity.To reconstruct paleosalinity more accurately,more detailed research on the modern hydrochemical characteristics of lakes and the relationship between the element ratios of carbonates and water salinity should be carried out. 展开更多
关键词 Mg/Ca and Sr/Ca ratios Partition coefficient lake evolution Paleoenvironmental reconstruction PALEOSALINITY HYDROCHEMISTRY Badain Jaran Desert Hydrogeology survey engineering
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Future Development Direction of the Restoration of Mountains,Rivers,Forests,Farmlands,Lakes,and Grasslands and the Faced Problems
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作者 Li CHEN 《Meteorological and Environmental Research》 2024年第5期9-13,共5页
In this paper,the definition,connotation,and internal relationship of mountains,rivers,forests,farmlands,lakes,and grasslands in China are elaborated,and the current situation of ecological restoration projects for mo... In this paper,the definition,connotation,and internal relationship of mountains,rivers,forests,farmlands,lakes,and grasslands in China are elaborated,and the current situation of ecological restoration projects for mountains,rivers,forests,farmlands,lakes,and grasslands was introduced.Moreover,the problems that have arisen in the specific implementation process of pilot projects were analyzed,such as unclear target positioning,inaccurate analysis of ecological problems,insufficient engineering design systematicness,weak operability of evaluation standards,and weak coordination in engineering management.The development direction and major needs for the protection and restoration of mountains,rivers,forests,farmlands,lakes,and grasslands in the future have been proposed from four aspects:theoretical research,engineering design,effect evaluation,and monitoring and supervision. 展开更多
关键词 Mountains rivers forests farmlands lakes and grasslands Restoration project Prominent problems Development direction
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Seasonal dynamics of wintering waterbirds in two shallow lakes along Yangtze River in Anhui Province 被引量:15
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作者 陈锦云 周立志 +3 位作者 周波 许仁鑫 朱文中 徐文彬 《Zoological Research》 CAS CSCD 北大核心 2011年第5期540-548,共9页
The shallow lake wetlands in the middle and lower Yangtze River floodplain are important wintering and stopover habitats for migratory waterbirds on the East Asia-Australia Flyway.With increasing fishery practices in ... The shallow lake wetlands in the middle and lower Yangtze River floodplain are important wintering and stopover habitats for migratory waterbirds on the East Asia-Australia Flyway.With increasing fishery practices in recent years,however,the wetlands have deteriorated significantly and now threaten wintering waterbirds.To gain insight into the influence of deteriorating wetlands on waterbirds,we conducted a survey of wintering waterbird species,population size,and distribution across 11 belt transects in Caizi Lake and Shengjin Lake,two shallow lakes along the Yangtze River in Anhui Province from November 2007-April 2008 and from November 2008-April 2009,respectively.The impacts of different fishery patterns on the distribution of waterbirds were also analyzed.A total of 43 waterbirds species belong to 7 orders of 12 families were counted during the surveys,of which 38 were found in Caizi Lake with a density of 8.2 ind./hm2,and 42 in Shengjin Lake with a density of 3.5 ind./hm2.Geese(Anser cygnoides),bean geese(Anser fabalis),tundra swan(Cygnus columbianus),and dunlin(Calidris alpina) were the dominant species in the two shallow lakes.Species number and individual assemble reached maximum at the end of December and in early January of the following year,without coincidence of the largest flock for different ecological groups.Based on waterbird diversity across the 11 belt transects and the fishery patterns,habitats could be divided into three groups.Gruiformes,Anseriformes and Charadriiformes had relatively higher densities in the natural fishery zones and lower densities in the cage fishery zones;whereas,the density of Ardeidae showed little change across all lake zones.It is important to develop sustainable fishery patterns in shallow lakes along the middle and lower Yangtze River floodplain to better protect resources of wintering waterbirds. 展开更多
关键词 Wintering waterbirds Community diversity Seasonal dynamic Fishery disturbance Caizi lake Shengjin lake
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低温下基于Lakes液的皖西白鹅精液稀释液研究 被引量:3
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作者 黄仁术 《畜牧与兽医》 北大核心 2009年第3期62-64,共3页
为研究低温(2—5℃)条件下皖西白鹅精液稀释液,以Lakes液为参考,通过更换糖(果糖、葡萄糖、蔗糖)和缓冲物质(柠檬酸钾、Tris、EDTA)来筛选最佳组合。结果表明:①Lakes液(果糖+柠檬酸钾)中,精子有效保存时间为42h,总保存... 为研究低温(2—5℃)条件下皖西白鹅精液稀释液,以Lakes液为参考,通过更换糖(果糖、葡萄糖、蔗糖)和缓冲物质(柠檬酸钾、Tris、EDTA)来筛选最佳组合。结果表明:①Lakes液(果糖+柠檬酸钾)中,精子有效保存时间为42h,总保存时间为234h。②与Lakes液相比,“果糖+Tris”组合最佳,精子有效保存时间为48h(P〈0.01),总保存时间为264h(P〈0.01);其次为“葡萄糖+Tris”组合,精子有效保存时间为43h(P〉0.05),总保存时间为240h(P〈0.01)。③其他组合的有效保存时间及总保存时间均低于Lakes液(P〈0.01)。 展开更多
关键词 精液稀释液 lakes 低温 皖西白鹅
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常温下基于Lakes液的皖西白鹅精液稀释液研究 被引量:1
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作者 黄仁术 《湖南农业科学》 2009年第1期125-126,130,共3页
为研究常温(20~25℃)条件下皖西白鹅精液稀释液,以Lakes液为参考,通过更换糖(果糖、葡萄糖、蔗糖)和缓冲物质(柠檬酸钾、Tris、EDTA)来筛选最佳组合。结果表明:①Lakes液(果糖+柠檬酸钾)中,精子有效保存时间为13h,总保存时间为74h。②... 为研究常温(20~25℃)条件下皖西白鹅精液稀释液,以Lakes液为参考,通过更换糖(果糖、葡萄糖、蔗糖)和缓冲物质(柠檬酸钾、Tris、EDTA)来筛选最佳组合。结果表明:①Lakes液(果糖+柠檬酸钾)中,精子有效保存时间为13h,总保存时间为74h。②与Lakes液相比",果糖+Tris"组合最佳,精子有效保存时间为16h(p<0.01),总保存时间为80h(p<0.01);其次为"葡萄糖+Tris"组合,精子有效保存时间为14h(p﹥0.05),总保存时间为78h(p<0.01)。③其它组合有效保存时间及总保存时间均低于Lakes液(p<0.01)。 展开更多
关键词 精液稀释液 lakes 常温 皖西白鹅
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Dynamic changes in lakes in the Hoh Xil region before and after the 2011 outburst of Zonag Lake 被引量:11
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作者 LIU Wen-hui XIE Chang-wei +6 位作者 ZHAO Lin WU Tong-hua WANG Wu ZHANG Yu-xin YANG Gui-qian ZHU Xiao-fan YUE Guang-yang 《Journal of Mountain Science》 SCIE CSCD 2019年第5期1098-1110,共13页
Zonag, Kusai, Hedin Noel and Yanhu Lakes are independent inland lakes in the Hoh Xil region on the Qinghai-Tibet Plateau. In September2011, Zonag Lake burst after the water level had increased for many years. Floods f... Zonag, Kusai, Hedin Noel and Yanhu Lakes are independent inland lakes in the Hoh Xil region on the Qinghai-Tibet Plateau. In September2011, Zonag Lake burst after the water level had increased for many years. Floods flowed through Kusai and Hedin Noel Lakes into Yanhu Lake; since then, the four small endorheic catchments merged into one larger catchment. This hydrological process caused the rapid shrinkage of Zonag Lake and continuous expansion of Yanhu Lake. In this study,based on satellite images, meteorological data and field investigations, we examined the dynamic changes in the four lakes and analyzed the influencing factors. The results showed that before 2011, the trends in the four lake areas were similar and displayed several stages. The change in the area of Zonag Lake corresponded well to the change in annual precipitation(AP), but the magnitude of the change was less than that of a non-glacier-fed lake. Although increased precipitation was the dominant factor that caused Zonag Lake to expand, increased glacier melting and permafrost thawing due to climate warming also had significant effects. After the 2011 outburst of Zonag Lake, due to the increasing AP and accelerating glacier melting, the increases in water volume of the three lakes were absorbed by Yanhu Lake, and Yanhu Lake expanded considerably. According to the rapid growth rates in water level and lake area, Yanhu Lake is likely to burst in 1-2 years. 展开更多
关键词 Dynamic CHANGE lake areas Influencing factors GLACIER CHANGE PERMAFROST thawing Zonag lake
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Ecological and environmental water demand of the lakes in the Haihe-Luanhe Basin of North China 被引量:18
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作者 LiuJL YongZF 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第2期234-238,共5页
The purpose of this paper is to present a brief concept of the ecological and environmental water demand of lake. The present situation and affecting factors of lake ecological system in the Haihe\|Luanhe Basin of Nor... The purpose of this paper is to present a brief concept of the ecological and environmental water demand of lake. The present situation and affecting factors of lake ecological system in the Haihe\|Luanhe Basin of North China was analyzed. The calculating method of the ecological and environmental water demand of the lake basis on the water body and the calculating method of the ecological and environmental water demand of the lake basis on the aquatic ecosystem, wetland and vegetation were compared and discussed. As the examples of Baiyangdian Lake and Beidagang Lake in Haihe\|Luanhe river basin, the ecological and environmental water demand of the two lakes was calculated to be 27×10\+8m\+3. It is 6.75 times to the water demand according to the calculating method of the ecological and environmental water demand of the lake basis on the water body. The research result indicated: (1) The calculating methods of the ecological and environmental water demand of the lake basis on the aquatic ecosystem should be better than only basis on the water body of lake. (2) The data, such as area of the vegetation kind around and in the lake, the vegetation coefficient, the evaporating amount of the vegetation and the vegetation water demand itself around and in the lake are lack and urgent need. Some suggestions for controlling and regulating the water resource of the lake in North China were proposed. 展开更多
关键词 eco\|environment water demand lake the Haihe\|Luanhe Basin
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Middle-Late Pleistocene Glacial Lakes in the Grand Canyon of the Tsangpo River,Tibet 被引量:9
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作者 ZHU Song WU Zhenhan +2 位作者 ZHAO Xitao LI Jianping WANG Hua 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第1期266-283,共18页
Many moraines formed between Daduka and Chibai in the Tsangpo River valley since Middle Pleistocene. A prominent set of lacustrine and alluvial terraces on the valley margin along both the Tsangpo and Nyang Rivers for... Many moraines formed between Daduka and Chibai in the Tsangpo River valley since Middle Pleistocene. A prominent set of lacustrine and alluvial terraces on the valley margin along both the Tsangpo and Nyang Rivers formed during Quaternary glacial epoch demonstrate lakes were created by damming of the river. Research was conducted on the geological environment, contained sediments, spatial distribution, timing, and formation and destruction of these paleolakes. The lacustrine sediments 14C (10537±268 aBP at Linzhi Brick and Tile Factory, 22510±580 aBP and 13925±204 aBP at Bengga, 21096±1466 aBP at Yusong) and a series of ESR (electron spin resonance) ages at Linzhi town and previous data by other experts, paleolakes persisted for 691±305 kaBP middle Pleistocene ice age, 75-40 kaBP the early stage of last glacier, 27-8 kaBP Last Glacier Maximum (LGM), existence time of lakes gradually shorten represents glacial scale and dam moraine supply potential gradually cut down, paleolakes and dam scale also gradually diminished. This article calculated the average lacustrine sedimentary rate of Gega paleolake in LGM was 12.5 mm/a, demonstrates Mount Namjagbarwa uplifted strongly at the same time, the sedimentary rate of Gega paleolake is more larger than that of enclosed lakes of plateau inland shows the climatic variation of Mount Namjagbarwa is more larger and plateau margin uplifted more quicker than plateau inland. This article analyzed formation and decay cause about the Zelunglung glacier on the west flank of Mount Namjagbarwa got into the Tsangpo River valley and blocked it for tectonic and climatic factors. There is a site of blocking the valley from Gega to Chibai. This article according to moraines and lacustrine sediments yielded paleolakes scale: the lowest lake base altitude 2850 m, the highest lake surface altitude 3585 m, 3240 m and 3180 m, area 2885 km2, 820 km2 and 810 km2, lake maximum depth of 735 m, 390 m and 330 m. We disclose the reason that previous experts discovered there were different age moraines dividing line of altitude 3180 m at the entrance of the Tsangpo Grand Canyon is dammed lake erosive decay under altitude 3180 m moraines in the last glacier era covering moraines in the early ice age of late Pleistocene, top 3180 m in the last glacier moraine remained because ancient dammed lakes didn't erode it under 3180 m moraines in the early ice age of late Pleistocene exposed. The reason of the top elevation 3585 m moraines in the middle Pleistocene ice age likes that of altitude 3180 m. There were three times dammed lakes by glacier blocking the Tsangpo River during Quaternary glacial period. During other glacial and interglacial period the Zelunglung glacier often extended the valley but moraine supplemental speed of the dam was smaller than that of fluvial erosion and moraine movement, dam quickly disappeared and didn't form stable lake. 展开更多
关键词 Zelunglung glacier blocking river dammed lakes Tsangpo River Namjagbarwa
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Mapping of moraine dammed glacial lakes and assessment of their areal changes in the central and eastern Himalayas using satellite data 被引量:3
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作者 Sazeda BEGAM Dhrubajyoti SEN 《Journal of Mountain Science》 SCIE CSCD 2019年第1期77-94,共18页
The relatively rapid recession of glaciers in the Himalayas and formation of moraine dammed glacial lakes(MDGLs) in the recent past have increased the risk of glacier lake outburst floods(GLOF) in the countries of Nep... The relatively rapid recession of glaciers in the Himalayas and formation of moraine dammed glacial lakes(MDGLs) in the recent past have increased the risk of glacier lake outburst floods(GLOF) in the countries of Nepal and Bhutan and in the mountainous territory of Sikkim in India. As a product of climate change and global warming, such a risk has not only raised the level of threats to the habitation and infrastructure of the region, but has also contributed to the worsening of the balance of the unique ecosystem that exists in this domain that sustains several of the highest mountain peaks of the world. This study attempts to present an up to date mapping of the MDGLs in the central and eastern Himalayan regions using remote sensing data, with an objective to analyse their surface area variations with time from 1990 through 2015, disaggregated over six episodes. The study also includes the evaluation for susceptibility of MDGLs to GLOF with the least criteria decision analysis(LCDA). Forty two major MDGLs, each having a lake surface area greater than 0.2 km2, that were identified in the Himalayan ranges of Nepal, Bhutan, and Sikkim, have been categorized according to their surface area expansion rates in space and time. The lakes have been identified as located within the elevation range of 3800 m and6800 m above mean sea level(a msl). With a total surface area of 37.9 km2, these MDGLs as a whole were observed to have expanded by an astonishing 43.6% in area over the 25 year period of this study. A factor is introduced to numerically sort the lakes in terms of their relative yearly expansion rates, based on their interpretation of their surface area extents from satellite imageries. Verification of predicted GLOF events in the past using this factor with the limited field data as reported in literature indicates that the present analysis may be considered a sufficiently reliable and rapid technique for assessing the potential bursting susceptibility of the MDGLs. The analysis also indicates that, as of now, there are eight MDGLs in the region which appear to be in highly vulnerable states and have high chances in causing potential GLOF events anytime in the recent future. 展开更多
关键词 GLACIER RETREAT lakes MAPPING MORAINE dammed GLACIAL lake(MDGL) Surface area change of lakes Landsat imagery data Least criteria decision analysis(LCDA)
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Profile of hepatocyte apoptosis and bile lakes before and after bile duct decompression in severe obstructive jaundice patients 被引量:9
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作者 Toar JM Lalisang Raden Sjamsuhidajat +1 位作者 Nurjati C Siregar Akmal Taher 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2010年第5期520-523,共4页
BACKGROUND:Excessive hepatocyte apoptosis and bile lakes in severe obstructive jaundice might impair liver functions.Although decompression of the bile duct has been reported to improve liver functions in animal studi... BACKGROUND:Excessive hepatocyte apoptosis and bile lakes in severe obstructive jaundice might impair liver functions.Although decompression of the bile duct has been reported to improve liver functions in animal studies,the mechanism of obstruction differs from that in humans.This study aimed to determine the profiles of hepatocyte apoptosis and bile lakes following bile duct decompression in patients with severe obstructive jaundice in the clinical setting.METHODS:We conducted a 'before and after study' on severe obstructive jaundice patients as a model of inhibition of the excessive process by bile duct decompression.Specimens of liver biopsies were taken before and after decompression of the bile duct and then stained by terminal deoxynucleotide transferase-mediated dUTP nick end-labeling(TUNEL) to identify hepatocyte apoptosis and by hematoxilin-eosin(HE) to identify bile lakes.All measurements were independently done by 2 observers.RESULTS:Twenty-one severe obstructive jaundice patients were included.In all patients,excessive hepatocyte apoptosis and bile lakes were apparent.After decompression,the hepatocyte apoptosis index decreased from 53.1(SD 105) to 11.7(SD 13.6)(P<0.05),and the bile lakes from 23.6(SD 14.8) to 10.9(SD 6.9)(P<0.05).CONCLUSION:Bile duct decompression improves hepatocyte apoptosis and bile lakes in cases of severe obstructive jaundice,similar to the findings in animal studies. 展开更多
关键词 hepatocyte apoptosis bile lakes TUNEL obstructive jaundice bile duct decompression
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