The quality changes of shallow groundwater from karst hilly areas in Guiyang region of China impacted by the urbanization were investigated. The results show that the major ions in shallow groundwater from the karst h...The quality changes of shallow groundwater from karst hilly areas in Guiyang region of China impacted by the urbanization were investigated. The results show that the major ions in shallow groundwater from the karst hilly areas are mainly composed of HCO3^-, SO4^2-, Ca^2＋ and Mg^2＋, and the concentrations scopes of NO3^-, Cl^-, K^＋ and Na^＋ of the groundwater in agricultural, residential and industrial areas are 4.5-9.6, 2.8-7.1, 3.9-6.3 and 2.5-4.9 times higher than those in the forest areas, respectively. The concentrations of As, Pb and Cd of shallow groundwater in the industrial areas are also significantly enhanced, followed by those in the residential areas and the agricultural areas. The concentrations of NO3^-, SO4^2- , As, Pb and Cd of the groundwater in the industrial areas and those of NO3^- , SO4^2-, As and Cd of shallow groundwater in the residential areas reach grade Ⅲ of the Groundwater Quality Standard of China （GB/T 14848-93）, while the concentration of NO3^- in the groundwater from the industrial areas exceeds grade V. With the process of urbanization, NO3^- is the key factor to influence the groundwater quality in karst hilly areas, followed by SO4^2-, As, Pb and Cd.展开更多
The Covered Karst, which formed in subsoil environment and distributed in the Tibet Plateau and its eastern district, denuded on the ground surface in different degrees (forming stone pinnacles), but they had the good...The Covered Karst, which formed in subsoil environment and distributed in the Tibet Plateau and its eastern district, denuded on the ground surface in different degrees (forming stone pinnacles), but they had the good consistency in their characteristics. First, some kind of landform, such as stone pinnacles, rock well etc, kept the slippery rock surface. It was believed that they were resulted from the process in soil. Nearer the foot of rock the site was; more clear and integrated the form was. Second, the covered karst often associated with red weathering crust. Based on the character of the red weathering crust of the summit plane of Anduo Mountain, its forming environment was relatively humid and hot. Third, the best geomorphologic position, where the karst was bare, was not on the summit plane but on the slope.The baring degrees and later reworked characteristics of the covered karst made up of an integrated series. They could be divided into three kinds of districts according to their response to the Plateau uplift. (1) The western district, where the uplift was intensive, was mainly Tibet Plateau. For example, in Anduo Mountain, the covered karst was entirely denuded on the ground surface, and the rock surface was turned into mottled rock well because the frost weathering intensively reworked it. The red weathering crust was only kept in the bottom of rock, most of which was observed in the crack of limestone. The present karst process on the ground surface stopped. (2) The middle district, where the uplift degree was moderate, was mainly Yungui Plateau. The covered karst was partly denuded to form the stone pinnacles. Its part, which is baring, is changed to be aciculate and sharp\|pointed, and is active now. (3) The eastern district, where the uplift was weak, was mainly the northern part of Guangxi Province and the southern part of Hunan Province. The covered karst was entirely covered by soil and only observed in the section, which was excavated by human. The form of the covered karst generally had the typical character of the process below the soil.展开更多
The karst aquifers are the most important water resources in Southwest China,where displays the most continuous bare karst around the world and hold about 100 million people.With the rapid expansion of the urbanizatio...The karst aquifers are the most important water resources in Southwest China,where displays the most continuous bare karst around the world and hold about 100 million people.With the rapid expansion of the urbanization,development of the industry and agriculture,the groundwater quality has been degraded.Mineralization of the karst groundwater increases because of development of intensive agriculture.Concentrations of nitrate and sulphate increase notably as a result of the large amount of chemical fertilizer used in agriculture.Waste gas, waste water and waste residues produced in the processes of industrialization and urbanization cause groundwater acidification and an increase of pollutants such as nitrogen,phosphate,chloride,展开更多
基金Project(2006CB403205) supported by the National Key Basic Research Program of ChinaProject(40961030) supported by the National Natural Science Foundation of China
文摘The quality changes of shallow groundwater from karst hilly areas in Guiyang region of China impacted by the urbanization were investigated. The results show that the major ions in shallow groundwater from the karst hilly areas are mainly composed of HCO3^-, SO4^2-, Ca^2＋ and Mg^2＋, and the concentrations scopes of NO3^-, Cl^-, K^＋ and Na^＋ of the groundwater in agricultural, residential and industrial areas are 4.5-9.6, 2.8-7.1, 3.9-6.3 and 2.5-4.9 times higher than those in the forest areas, respectively. The concentrations of As, Pb and Cd of shallow groundwater in the industrial areas are also significantly enhanced, followed by those in the residential areas and the agricultural areas. The concentrations of NO3^-, SO4^2- , As, Pb and Cd of the groundwater in the industrial areas and those of NO3^- , SO4^2-, As and Cd of shallow groundwater in the residential areas reach grade Ⅲ of the Groundwater Quality Standard of China （GB/T 14848-93）, while the concentration of NO3^- in the groundwater from the industrial areas exceeds grade V. With the process of urbanization, NO3^- is the key factor to influence the groundwater quality in karst hilly areas, followed by SO4^2-, As, Pb and Cd.
文摘The Covered Karst, which formed in subsoil environment and distributed in the Tibet Plateau and its eastern district, denuded on the ground surface in different degrees (forming stone pinnacles), but they had the good consistency in their characteristics. First, some kind of landform, such as stone pinnacles, rock well etc, kept the slippery rock surface. It was believed that they were resulted from the process in soil. Nearer the foot of rock the site was; more clear and integrated the form was. Second, the covered karst often associated with red weathering crust. Based on the character of the red weathering crust of the summit plane of Anduo Mountain, its forming environment was relatively humid and hot. Third, the best geomorphologic position, where the karst was bare, was not on the summit plane but on the slope.The baring degrees and later reworked characteristics of the covered karst made up of an integrated series. They could be divided into three kinds of districts according to their response to the Plateau uplift. (1) The western district, where the uplift was intensive, was mainly Tibet Plateau. For example, in Anduo Mountain, the covered karst was entirely denuded on the ground surface, and the rock surface was turned into mottled rock well because the frost weathering intensively reworked it. The red weathering crust was only kept in the bottom of rock, most of which was observed in the crack of limestone. The present karst process on the ground surface stopped. (2) The middle district, where the uplift degree was moderate, was mainly Yungui Plateau. The covered karst was partly denuded to form the stone pinnacles. Its part, which is baring, is changed to be aciculate and sharp\|pointed, and is active now. (3) The eastern district, where the uplift was weak, was mainly the northern part of Guangxi Province and the southern part of Hunan Province. The covered karst was entirely covered by soil and only observed in the section, which was excavated by human. The form of the covered karst generally had the typical character of the process below the soil.
文摘The karst aquifers are the most important water resources in Southwest China,where displays the most continuous bare karst around the world and hold about 100 million people.With the rapid expansion of the urbanization,development of the industry and agriculture,the groundwater quality has been degraded.Mineralization of the karst groundwater increases because of development of intensive agriculture.Concentrations of nitrate and sulphate increase notably as a result of the large amount of chemical fertilizer used in agriculture.Waste gas, waste water and waste residues produced in the processes of industrialization and urbanization cause groundwater acidification and an increase of pollutants such as nitrogen,phosphate,chloride,
