Stormwater runoff in rural townships has a high potential for water quality impairment but little information is available on strormwater runoff pollution from rural townships.To investigate the characteristics of run...Stormwater runoff in rural townships has a high potential for water quality impairment but little information is available on strormwater runoff pollution from rural townships.To investigate the characteristics of runoff pollution in a rural township,a catchment(2.32 ha) in Linshan Township,Sichuan,China was selected to examine runoff and quality parameters including precipitation,flow rate,and total nitrogen(TN),dissolved nitrogen(DN),total phosphorus(TP),dissolved phosphorus(DP),particulate phosphorus(PP),chemical oxygen demand(COD) and suspended solid(SS) in 12 rainfall events occurring between June 2006 and July 2007.Results show that the annual pollutant loads were 47.17 kg ha-1 for TN,6.64 kg ha-1 for TP,1186 kg ha-1 for COD,and 4297 kg ha-1 for SS.DN and PP were the main forms of nitrogen and phosphorus in stormwater runoff.TP,COD and SS showed medium mass first flushes,in which nearly 40% of the total pollutant masses were transported by the first 30% of total flow volume.The peak of pollutant concentration appeared before the peak of runoff due to the first flush of accumulative pollutants in impervious areas and drainage ditches.The EMC values of TN,TP,DN and PP were negatively correlated to the maximum rainfall intensity,precipitation,total flow volume,and runoff duration(P<0.05,n=12),while EMC of COD and SS were not related to any rainfall characteristics.The FF30(FF,First Flush) for TN,TP,COD and SS were positively correlated to the maximum rainfall intensity(P<0.05,n=12),and TP was also positively correlated to the average rainfall intensity(P<0.05,n=12),indicating that the magnitude of first flush increased with the rainfall intensity in the Linshan Township.展开更多
文摘根据常规观测资料、四川地面自动站资料和SWAN雷达拼图产品、四川盆地多普勒雷达PUP产品,统计分析了2010-2013年四川盆地区域性暴雨中35次个例的雷达回波形态演变特征以及线（带）状回波的列车效应特征,结果表明,在地形和850 hPa风的相互作用下,初始回波生成地点主要在盆地山区边缘附近,生成时间主要在下午到上半夜,其中16：00-19：00是回波生成的高发期;初步揭示了四川盆地线（带）状回波和块状回波的形成机制,建立了盆地西部、北部、中南部强降雨概念模型;当出现线（带）状回波或块状回波时,是发布暴雨预警信号的最佳时机,暴雨预警落区准确性高,预警时效平均可达5～8 h.
基金supports from the Western Development Plan of CAS (No. KZCX2-XB3-09)the Project of National Science & Technology Pillar Program (No. 2011BAD31B03)
文摘Stormwater runoff in rural townships has a high potential for water quality impairment but little information is available on strormwater runoff pollution from rural townships.To investigate the characteristics of runoff pollution in a rural township,a catchment(2.32 ha) in Linshan Township,Sichuan,China was selected to examine runoff and quality parameters including precipitation,flow rate,and total nitrogen(TN),dissolved nitrogen(DN),total phosphorus(TP),dissolved phosphorus(DP),particulate phosphorus(PP),chemical oxygen demand(COD) and suspended solid(SS) in 12 rainfall events occurring between June 2006 and July 2007.Results show that the annual pollutant loads were 47.17 kg ha-1 for TN,6.64 kg ha-1 for TP,1186 kg ha-1 for COD,and 4297 kg ha-1 for SS.DN and PP were the main forms of nitrogen and phosphorus in stormwater runoff.TP,COD and SS showed medium mass first flushes,in which nearly 40% of the total pollutant masses were transported by the first 30% of total flow volume.The peak of pollutant concentration appeared before the peak of runoff due to the first flush of accumulative pollutants in impervious areas and drainage ditches.The EMC values of TN,TP,DN and PP were negatively correlated to the maximum rainfall intensity,precipitation,total flow volume,and runoff duration(P<0.05,n=12),while EMC of COD and SS were not related to any rainfall characteristics.The FF30(FF,First Flush) for TN,TP,COD and SS were positively correlated to the maximum rainfall intensity(P<0.05,n=12),and TP was also positively correlated to the average rainfall intensity(P<0.05,n=12),indicating that the magnitude of first flush increased with the rainfall intensity in the Linshan Township.
