Use of 18O, 2H and 15N to identify nitrate contamination of groundwater in a wastewater irrigated field near the city of Shijiazhuang, China

摘要: Wastewater irrigation was initiated as early 1958 in the suburb of Shijiazhuang, China. This has resulted groundwater becoming contaminated by nitrate to a depth about 100 m with an average concentration 40 mg NO(3)(-)/L. The annual rate wastewater this area is 430 mm, and water table relatively stable contrast surrounding area, where no been used. Although different composition, old are found be well mixed based on linearity delta(18)O Cl(-). high Cl-, but detectable nitrate. Dominance delta(15)N range 7-11 parts per thousand AIR (referred atmospheric N(2) standard) confirms that present originates from wastewater. Nitrate then used tracer estimate roughly movement rates, yielding vertical 2.0-2.5 m/y horizontal 41.8-62.5 m/y. Denitrification could occur zone 2 km canal, which fraction contributed calculated 76%. Health concerns should raised regarding irrigation, common practice suburbs principal cities China, especially semi-arid regions. (c) 2005 Elsevier B.V. All rights reserved.