The quality of shallow groundwater in the West Lake watershed was investigated from March to July 2000. Integrating with Blackland GRASS GIS system, the DRASTIC model was used to compile the groud-water vulnerability ...The quality of shallow groundwater in the West Lake watershed was investigated from March to July 2000. Integrating with Blackland GRASS GIS system, the DRASTIC model was used to compile the groud-water vulnerability map. A land use factor was added to the DRASTIC model and the modified model (LDRASTIC) increased the accuracy of prediction from 26.9% to 51.3%. The vulnerability map showed that the lowly, moderately and highly susceptible area predicted occupied about 11.6%, 70.9% and 17.5% of the whole watershed, respectively. Compared with the observed values of nitrate and electric conductivity, the LDRASTIC index improved the Pearson correlation coefficients from -0.010 to 0.237 and 0.380 to 0.503 both the improved coefficients were significant at the 0.01 level. The modified DRASTIC analysis showed a great potential as a screening tool for policy decision-making in groundwater management.展开更多
基金Project supported by the British Council (No. SHA/992/297) and the Zhejiang Provincial Science and Technology Development Found
文摘The quality of shallow groundwater in the West Lake watershed was investigated from March to July 2000. Integrating with Blackland GRASS GIS system, the DRASTIC model was used to compile the groud-water vulnerability map. A land use factor was added to the DRASTIC model and the modified model (LDRASTIC) increased the accuracy of prediction from 26.9% to 51.3%. The vulnerability map showed that the lowly, moderately and highly susceptible area predicted occupied about 11.6%, 70.9% and 17.5% of the whole watershed, respectively. Compared with the observed values of nitrate and electric conductivity, the LDRASTIC index improved the Pearson correlation coefficients from -0.010 to 0.237 and 0.380 to 0.503 both the improved coefficients were significant at the 0.01 level. The modified DRASTIC analysis showed a great potential as a screening tool for policy decision-making in groundwater management.
