In Tunisia,water scarcity is only adding pressure on water demand in agriculture.In the context of sustainable development goals,Tunisia has been reusing treated wastewater(TWW)as a renewable and inexpensive source fo...In Tunisia,water scarcity is only adding pressure on water demand in agriculture.In the context of sustainable development goals,Tunisia has been reusing treated wastewater(TWW)as a renewable and inexpensive source for soil fertigation and groundwater(GW)recharge.However,major risks can be expected when the irrigation water is of poor quality.This study aims for evaluating the potential risk of TWW and GW irrigation on soil parameters.Accordingly,we evaluated the suitability of water quality through the analysis of major and minor cations and anions,metallic trace elements(MTEs),and the sodium hazard by using the sodium adsorption ratio(SAR)and the soluble sodium percentage(SSP).The risk of soil sodicity was further assessed by SAR and the exchangeable sodium percentage(ESP).The degree of soil pollution caused by MTEs accumulation was evaluated using geoaccumulation index(Igeo)and pollution load index(PLI).Soil maps were generated using inverse spline interpolation in ArcGIS software.The results show that both water samples(i.e.,TWW and GW)are suitable for soil irrigation in terms of salinity(electrical conductivity<7000μS/cm)and sodicity(SAR<10.00;SSP<60.00%).However,the contents of PO_(4)^(3-),Cu^(2+),and Cd^(2+)exceed the maximum threshold values set by the national and other standards.Concerning the soil samples,the average levels of SAR and ESP are within the standards(SAR<13.00;ESP<15.00%).On the other hand,PLI results reveal moderate pollution in the plot irrigated with TWW and no to moderate pollution in the plot irrigated with GW.Igeo results indicate that Cu^(2+)is the metallic trace element(MTE)with the highest risk of soil pollution in both plots(Igeo>5.00),followed by Ni^(2+)and Pb^(2+).Nevertheless,Cd^(2+)presents the lowest risk of soil pollution(Igeo<0.00).Statistical data indicates that Ca^(2+),Na+,Ni^(2+),and Pb^(2+)are highly distributed in both plots(coefficient of variation>50.0%).This study shows that the use of imagery tools,such as ArcGIS,can provide important information for evaluating t展开更多
This study was conducted to reveal the vertical distribution and concentration variation of heavy metals（Cr, Co, Ni, Cu, Zn, As, Cd and Pb） in the mangrove sediments of Dongzhai Harbor, Hainan by using inductively-c...This study was conducted to reveal the vertical distribution and concentration variation of heavy metals（Cr, Co, Ni, Cu, Zn, As, Cd and Pb） in the mangrove sediments of Dongzhai Harbor, Hainan by using inductively-coupled plasma mass spectrometry（ICP-MS）. The surface sediment samples were collected from 15 sites, and a geoaccumulation index（Igeo） was estimated to quantify the pollution status of the mangrove sediments. The results showed that the concentrations of heavy metals in sediments followed the order of Cr〉 Zn〉 Ni〉 Cu 〉Pb 〉Co〉 Cd. A common pattern was found in some heavy metals（Cu, Zn, As and Pb） as their concentrations were significantly and negatively correlated with depth. Cr concentration in upper layer was slightly lower than that in middle and lower layers,while the concentrations of Ni and Cd in middle layer were slightly higher than in upper and lower layers. The geoaccumulation index indicated that the surface sediments at sites QT-1-01, QT-1-02, QT-2, GN-1, GN-2 and GN-3 were strongly polluted by Cd, and unpolluted to moderately polluted or moderately polluted by As.展开更多
文摘In Tunisia,water scarcity is only adding pressure on water demand in agriculture.In the context of sustainable development goals,Tunisia has been reusing treated wastewater(TWW)as a renewable and inexpensive source for soil fertigation and groundwater(GW)recharge.However,major risks can be expected when the irrigation water is of poor quality.This study aims for evaluating the potential risk of TWW and GW irrigation on soil parameters.Accordingly,we evaluated the suitability of water quality through the analysis of major and minor cations and anions,metallic trace elements(MTEs),and the sodium hazard by using the sodium adsorption ratio(SAR)and the soluble sodium percentage(SSP).The risk of soil sodicity was further assessed by SAR and the exchangeable sodium percentage(ESP).The degree of soil pollution caused by MTEs accumulation was evaluated using geoaccumulation index(Igeo)and pollution load index(PLI).Soil maps were generated using inverse spline interpolation in ArcGIS software.The results show that both water samples(i.e.,TWW and GW)are suitable for soil irrigation in terms of salinity(electrical conductivity<7000μS/cm)and sodicity(SAR<10.00;SSP<60.00%).However,the contents of PO_(4)^(3-),Cu^(2+),and Cd^(2+)exceed the maximum threshold values set by the national and other standards.Concerning the soil samples,the average levels of SAR and ESP are within the standards(SAR<13.00;ESP<15.00%).On the other hand,PLI results reveal moderate pollution in the plot irrigated with TWW and no to moderate pollution in the plot irrigated with GW.Igeo results indicate that Cu^(2+)is the metallic trace element(MTE)with the highest risk of soil pollution in both plots(Igeo>5.00),followed by Ni^(2+)and Pb^(2+).Nevertheless,Cd^(2+)presents the lowest risk of soil pollution(Igeo<0.00).Statistical data indicates that Ca^(2+),Na+,Ni^(2+),and Pb^(2+)are highly distributed in both plots(coefficient of variation>50.0%).This study shows that the use of imagery tools,such as ArcGIS,can provide important information for evaluating t
基金Supported by the National Natural Science Foundation of China(41261062)Key Science and Technology Project of Hainan(ZDXM20130021)~~
文摘This study was conducted to reveal the vertical distribution and concentration variation of heavy metals（Cr, Co, Ni, Cu, Zn, As, Cd and Pb） in the mangrove sediments of Dongzhai Harbor, Hainan by using inductively-coupled plasma mass spectrometry（ICP-MS）. The surface sediment samples were collected from 15 sites, and a geoaccumulation index（Igeo） was estimated to quantify the pollution status of the mangrove sediments. The results showed that the concentrations of heavy metals in sediments followed the order of Cr〉 Zn〉 Ni〉 Cu 〉Pb 〉Co〉 Cd. A common pattern was found in some heavy metals（Cu, Zn, As and Pb） as their concentrations were significantly and negatively correlated with depth. Cr concentration in upper layer was slightly lower than that in middle and lower layers,while the concentrations of Ni and Cd in middle layer were slightly higher than in upper and lower layers. The geoaccumulation index indicated that the surface sediments at sites QT-1-01, QT-1-02, QT-2, GN-1, GN-2 and GN-3 were strongly polluted by Cd, and unpolluted to moderately polluted or moderately polluted by As.
