文档介绍：Nitrogen fertilizer application under double cropping
systems of wheat-maize impacting on the nitrate
contents of ground water in North China
Dafu Wu, Hongwei Chen, Yanbing Wu S. J. Chapman
Henan Institute of Science and Technology Macaulay Institute, Craigiebuckler
Xinxiang, 453003, Aberdeen, AB15 8QU, UK
******@hist.
Abstract—Sixty households were surveyed in Jingxian County, concern for both health and environmental reasons. Elevated
Hebei Province, and Xinxiang County, Henan Province, North concentrations of nitrate N may be reduced to nitrite by
China. Sampling of ground water from wells showed that nitrate bacteria in the intestines of newborn infants and thereby cause
contents were no more than 3 mg l-1. In contrast, water samples the disease methemoglobinemia[3]. mission of the
drawn from Huantai County, Shandong Province, and Wenxian munities, in particular with its Green Book, for
County, Henan Province gave nitrate contents for five water
-1 the first time did officially recognize the need for
samples over the EC standard, reaching 95 mg l . The environmental safeguards in the field of agriculture. As a
proportions of samples over standard were % and % in safeguard against methemoglobinemia, the European
Wenxian and Huantai counties, respectively. In these munity (EC) imposed a limited of 50 mg l-1 for nit