Heavy metal pollution is hazardous for the environment and human health.However,there are few studies of heavy metal pollution caused by historic metallurgical activity.The Laoniupo site in the Bahe River valley,Guanz...Heavy metal pollution is hazardous for the environment and human health.However,there are few studies of heavy metal pollution caused by historic metallurgical activity.The Laoniupo site in the Bahe River valley,Guanzhong Basin,China,was an important settlement of the Shang Culture(1600-1046 BCE).We studied two stratigraphic profiles at the Laoniupo site,which were used for measurements of magnetic susceptibility,heavy metal concentrations,and AMS 14C ages to provide evidence of copper smelting activity at the site during the Shang Dynasty.The Nemerow Pollution Index and Geoaccumulation Index were calculated to assess the heavy metals record(Cu,Zn,Ni,Pb,Cr,and As)in the topsoil on the loess tableland.According to the Single Pollution Index,the topsoil was slightly polluted by As and unpolluted by Cu,Zn,Ni,Pb and Cr;according to the Nemerow Composite Pollution Index the topsoil was mildly polluted;and according to the Geoaccumulation Index,the topsoil was moderately polluted by As,slightly polluted by Cu,and unpolluted by Zn,Ni,Pb and Cr_The main cause of the heavy metal pollution in the topsoil is the presence of copper slag in the cultural layers that was disturbed by modern farming activity.展开更多
In recent years, global reanalysis weather data has been widely used in hydrological modeling around the world, but the results of simulations vary greatly. To consider the applicability of Climate Forecast System Rea...In recent years, global reanalysis weather data has been widely used in hydrological modeling around the world, but the results of simulations vary greatly. To consider the applicability of Climate Forecast System Reanalysis(CFSR) data in the hydrologic simulation of watersheds, the Bahe River Basin was used as a case study. Two types of weather data(conventional weather data and CFSR weather data) were considered to establish a Soil and Water Assessment Tool(SWAT) model, which was used to simulate runoff from 2001 to 2012 in the basin at annual and monthly scales. The effect of both datasets on the simulation was assessed using regression analysis, Nash-Sutcliffe Efficiency(NSE), and Percent Bias(PBIAS). A CFSR weather data correction method was proposed. The main results were as follows.(1) The CFSR climate data was applicable for hydrologic simulation in the Bahe River Basin(R^2 of the simulated results above 0.50, NSE above 0.33, and |PBIAS| below 14.8. Although the quality of the CFSR weather data is not perfect, it achieved a satisfactory hydrological simulation after rainfall data correction.(2) The simulated streamflow using the CFSR data was higher than the observed streamflow, which was likely because the estimation of daily rainfall data by CFSR weather data resulted in more rainy days and stronger rainfall intensity than was actually observed. Therefore, the data simulated a higher base flow and flood peak discharge in terms of the water balance, except for some individual years.(3) The relation between the CFSR rainfall data(x) and the observed rainfall data(y) could berepresented by a power exponent equation: y=1.4789x0.8875(R2=0.98,P〈0.001). There was a slight variation between the fitted equations for each station. The equation provides a theoretical basis for the correction of CFSR rainfall data.展开更多
基金National Natural Science Foundation of China,No.41801060The Strategic Priority Research Program of the Chinese Academy of Sciences,No.XDA20060201The Open Foundation of the Key Laboratory of Cultural Heritage Research and Conservation of the Education Ministry in Northwest University of China,No.GXYDFA2018XBD003,No.WYSYS2019。
文摘Heavy metal pollution is hazardous for the environment and human health.However,there are few studies of heavy metal pollution caused by historic metallurgical activity.The Laoniupo site in the Bahe River valley,Guanzhong Basin,China,was an important settlement of the Shang Culture(1600-1046 BCE).We studied two stratigraphic profiles at the Laoniupo site,which were used for measurements of magnetic susceptibility,heavy metal concentrations,and AMS 14C ages to provide evidence of copper smelting activity at the site during the Shang Dynasty.The Nemerow Pollution Index and Geoaccumulation Index were calculated to assess the heavy metals record(Cu,Zn,Ni,Pb,Cr,and As)in the topsoil on the loess tableland.According to the Single Pollution Index,the topsoil was slightly polluted by As and unpolluted by Cu,Zn,Ni,Pb and Cr;according to the Nemerow Composite Pollution Index the topsoil was mildly polluted;and according to the Geoaccumulation Index,the topsoil was moderately polluted by As,slightly polluted by Cu,and unpolluted by Zn,Ni,Pb and Cr_The main cause of the heavy metal pollution in the topsoil is the presence of copper slag in the cultural layers that was disturbed by modern farming activity.
基金International Partnership Program of Chinese Academy of Sciences,No.131551KYSB20160002 National Natural Science Foundation of China,No.41401602+2 种基金 Natural Science Basic Research Plan in Shaanxi Province of China,No.2014JQ2-4021 Key Scientific and Technological Innovation Team Plan of Shaanxi Province,No.2014KCT-27 Graduate Student Innovation Project of Northwest University,No.YZZ15011
文摘In recent years, global reanalysis weather data has been widely used in hydrological modeling around the world, but the results of simulations vary greatly. To consider the applicability of Climate Forecast System Reanalysis(CFSR) data in the hydrologic simulation of watersheds, the Bahe River Basin was used as a case study. Two types of weather data(conventional weather data and CFSR weather data) were considered to establish a Soil and Water Assessment Tool(SWAT) model, which was used to simulate runoff from 2001 to 2012 in the basin at annual and monthly scales. The effect of both datasets on the simulation was assessed using regression analysis, Nash-Sutcliffe Efficiency(NSE), and Percent Bias(PBIAS). A CFSR weather data correction method was proposed. The main results were as follows.(1) The CFSR climate data was applicable for hydrologic simulation in the Bahe River Basin(R^2 of the simulated results above 0.50, NSE above 0.33, and |PBIAS| below 14.8. Although the quality of the CFSR weather data is not perfect, it achieved a satisfactory hydrological simulation after rainfall data correction.(2) The simulated streamflow using the CFSR data was higher than the observed streamflow, which was likely because the estimation of daily rainfall data by CFSR weather data resulted in more rainy days and stronger rainfall intensity than was actually observed. Therefore, the data simulated a higher base flow and flood peak discharge in terms of the water balance, except for some individual years.(3) The relation between the CFSR rainfall data(x) and the observed rainfall data(y) could berepresented by a power exponent equation: y=1.4789x0.8875(R2=0.98,P〈0.001). There was a slight variation between the fitted equations for each station. The equation provides a theoretical basis for the correction of CFSR rainfall data.