Distribution of nitrate and its implication for the contaminant source in groundwater of Huaibei Plain, Anhui Province

High concentration of NO3-N in groundwater can pose risk to human's health, thus the study of NO3-N contamination in groundwater is a very important issue related to public health. Using a typical agriculture zone, Huaibei plain in Anhui Province of China as a field site, the temporal and spatial variation of groundwater NO3-N concentration was studied using a multivariate statistical factor analysis combined with Kaiser-Meyer-Olkin method based on a hydrogeological investigation from 2005 to 2009 year. The results show: (1) The contaminant in the groundwater of Huaibei Plain in Anhui Province are serious. 10% of the shallow groundwater samples in non-rainy season of 2005 exceeds the recommended value of NO3-N by Chinese drinking water standard (<= 20 mg/L), while 17.5% exceeds the recommended value (11.3 mg/L) by EC. (2) About 15% of shallow groundwater in the whole study area was polluted in 2005 with the maximum of 97.67 mg/L; Groundwater NO3-N concentration is higher in non-rainy season than in rainy season. And the NO3-N content in groundwater shows the increasing trend at all three depths sampled from 2005 to 2009 year. (3) Groundwater nitrate pollution mainly derives from anthropogenic activities in Huaibei Plain, Anhui Province. Further quantitative analysis need to be studied in the future.