The special geography and human environment of the Qinghai-Tibet Plateau has created the unique hydrochemical characteristics of the region’s natural water,which has been preserved in a largely natural state.However,...The special geography and human environment of the Qinghai-Tibet Plateau has created the unique hydrochemical characteristics of the region’s natural water,which has been preserved in a largely natural state.However,as the intensity of anthropogenic activities in the region has continued to increase,the water environment and hydrochemical characteristics of the Qinghai-Tibet Plateau have altered.In this study,water samples from the western,southern,and northeastern border areas of the Qinghai-Tibet Plateau,where human activities are ongoing,were collected,analyzed,and measured.The regional differences and factors controlling them were also investigated.The key results were obtained as follows.(1) Differences in the physical properties and hydrochemical characteristics,and their controlling factors,occurred in the different boundary areas of the Qinghai-Tibet Plateau.These differences were mainly the consequence of the geographical environment and geological conditions.(2) The water quality was good and suitable for drinking,with most samples meeting GB (Chinese national) and WHO (World Health Organization) drinking water standards.(3) The chemical properties of water were mainly controlled by the weathering of carbonates and the dissolution of evaporative rocks,with the former the most influential.(4) The biological quality indicators of natural water in the border areas were far superior to GB and WHO drinking water standards.展开更多
This study investigated Linzhou County in Tibet, which currently hosts the most serious outbreak of Kashin-Beck disease(KBD) in China. This study uses the geographical detector(GeoDetector) algorithm to measure the in...This study investigated Linzhou County in Tibet, which currently hosts the most serious outbreak of Kashin-Beck disease(KBD) in China. This study uses the geographical detector(GeoDetector) algorithm to measure the influences that several risk factors have on KBD prevalence and validates the spatial analysis results with environmental chemistry. Based on a comprehensive examination of 10 potentially related spatial factors and an environmental chemistry analysis of the soil-water-grain-human biogeochemical cycle in the local KBD and non-KBD villages, four main conclusions are drawn.(1) KBD in Linzhou County is a consequence of multiple interrelated environmental factors, of which the most important controlling factor is the stratum factor.(2) The concentrations of selenium(Se) in all environmental media(soil, water, and food) and human tissue in the KBD villages in Linzhou County are lower than those of the non-KBD villages.(3) The intake of Se and chromium(Cr) by local residents is seriously insufficient, especially the average daily dose by ingestion(ADD) for Se in the KBD village, which is only about 4% of the World Health Organization(WHO) recommended lower limit for adult elemental intake.(4) We speculate that the main cause for the local KBD outbreak is a lack of Se in the stratum. This absence leads to a serious Se deficiency in the local population through ecosystem migration and transformation, which will eventually lead to an endemic biogeochemical Se deficiency.展开更多
The North Tibet plateau is the world highest plateau with a unique alpine grassland and water environment. To obtain a better understanding of the correct supply of Molybdenum（Mo） to livestock in north Tibet,we inve...The North Tibet plateau is the world highest plateau with a unique alpine grassland and water environment. To obtain a better understanding of the correct supply of Molybdenum（Mo） to livestock in north Tibet,we investigated the content and geographical variation of Mo in different families of pasture plants（n=1017） and water（n=40）,then discuss the Cuprum（Cu）：Mo ratio in different plant families,and calculate the total Mo intake of the yak in north Tibet. The average Mo concentration in five families preferred for grazing are： Compositae（2.71 μg g^（-1））,Leguminosae（2.70 μg g^（-1））,Gramineae（2.48 μg g^（-1））,Cyperaceae（1.63 μg g^（-1））,and Rosaceae（1.51 μg g^（-1））. There was a strong geographical variation in Mo concentration（p 0.001）. The mean value of Mo in north Tibet surface water from 15 sites is 0.89 μg L^（-1）. The Mo ingestion by yak through these plants and water in north Tibet is about 9586 μg day^（-1） which means the toxicity of Mo does not exist in the average daily diet. However,the large geographical variation found may cause some toxicity of Mo in the average daily intake of north Tibet pasture plants in some areas. The Cu：Mo ratio of 2：60 is considered the limit for risk of Mo hyperactivity,while extremely high Cu：Mo ratios may lead to chronic copper poisoning. Our survey of plant samples found 43.29% below and 29.3% above the limiting Cu：Mo ratio of 60 indicating some risk to north Tibet livestock.展开更多
基金Key R&D and Transformation Program of Tibet,No.XZ201901NB08Major Science and Technology Project of Tibet,No.XZ201901NA03,No.XZ201801NA02
文摘The special geography and human environment of the Qinghai-Tibet Plateau has created the unique hydrochemical characteristics of the region’s natural water,which has been preserved in a largely natural state.However,as the intensity of anthropogenic activities in the region has continued to increase,the water environment and hydrochemical characteristics of the Qinghai-Tibet Plateau have altered.In this study,water samples from the western,southern,and northeastern border areas of the Qinghai-Tibet Plateau,where human activities are ongoing,were collected,analyzed,and measured.The regional differences and factors controlling them were also investigated.The key results were obtained as follows.(1) Differences in the physical properties and hydrochemical characteristics,and their controlling factors,occurred in the different boundary areas of the Qinghai-Tibet Plateau.These differences were mainly the consequence of the geographical environment and geological conditions.(2) The water quality was good and suitable for drinking,with most samples meeting GB (Chinese national) and WHO (World Health Organization) drinking water standards.(3) The chemical properties of water were mainly controlled by the weathering of carbonates and the dissolution of evaporative rocks,with the former the most influential.(4) The biological quality indicators of natural water in the border areas were far superior to GB and WHO drinking water standards.
基金The Key Research and Development and Transformation Program of Tibet(XZ201901NB08)The Major Science and Technology Project of Tibet(XZ201901NA03,XZ201801NA02).
文摘This study investigated Linzhou County in Tibet, which currently hosts the most serious outbreak of Kashin-Beck disease(KBD) in China. This study uses the geographical detector(GeoDetector) algorithm to measure the influences that several risk factors have on KBD prevalence and validates the spatial analysis results with environmental chemistry. Based on a comprehensive examination of 10 potentially related spatial factors and an environmental chemistry analysis of the soil-water-grain-human biogeochemical cycle in the local KBD and non-KBD villages, four main conclusions are drawn.(1) KBD in Linzhou County is a consequence of multiple interrelated environmental factors, of which the most important controlling factor is the stratum factor.(2) The concentrations of selenium(Se) in all environmental media(soil, water, and food) and human tissue in the KBD villages in Linzhou County are lower than those of the non-KBD villages.(3) The intake of Se and chromium(Cr) by local residents is seriously insufficient, especially the average daily dose by ingestion(ADD) for Se in the KBD village, which is only about 4% of the World Health Organization(WHO) recommended lower limit for adult elemental intake.(4) We speculate that the main cause for the local KBD outbreak is a lack of Se in the stratum. This absence leads to a serious Se deficiency in the local population through ecosystem migration and transformation, which will eventually lead to an endemic biogeochemical Se deficiency.
基金Key Science and Technology Research Program of Tibet(ZDZX2017000122,XZ201801NA02)Natural Science Foundation of Tibet(2016ZR-15-76)Key Science and Technology Research Program of Tibet(Z2016C01G01)
文摘The North Tibet plateau is the world highest plateau with a unique alpine grassland and water environment. To obtain a better understanding of the correct supply of Molybdenum（Mo） to livestock in north Tibet,we investigated the content and geographical variation of Mo in different families of pasture plants（n=1017） and water（n=40）,then discuss the Cuprum（Cu）：Mo ratio in different plant families,and calculate the total Mo intake of the yak in north Tibet. The average Mo concentration in five families preferred for grazing are： Compositae（2.71 μg g^（-1））,Leguminosae（2.70 μg g^（-1））,Gramineae（2.48 μg g^（-1））,Cyperaceae（1.63 μg g^（-1））,and Rosaceae（1.51 μg g^（-1））. There was a strong geographical variation in Mo concentration（p 0.001）. The mean value of Mo in north Tibet surface water from 15 sites is 0.89 μg L^（-1）. The Mo ingestion by yak through these plants and water in north Tibet is about 9586 μg day^（-1） which means the toxicity of Mo does not exist in the average daily diet. However,the large geographical variation found may cause some toxicity of Mo in the average daily intake of north Tibet pasture plants in some areas. The Cu：Mo ratio of 2：60 is considered the limit for risk of Mo hyperactivity,while extremely high Cu：Mo ratios may lead to chronic copper poisoning. Our survey of plant samples found 43.29% below and 29.3% above the limiting Cu：Mo ratio of 60 indicating some risk to north Tibet livestock.
