关键词: 夏玉米, 施氮时期, 氮代谢关键酶, 抗氧化特性

Abstract: This paper makes a qualitative and quantitative analysis of organic compounds in industrial pollution sources, water body and bottom mud of Xiaoqing river and soils,underground water and agricultural products of sewage-irrigated area；studies their category,source,distribution and turnover in farmland ecosystems of sewage-irrigated area；carries out germination test and pot and field experiments with wheat to reveaI the influence of sewage irrigation on crop growth and development；and studies the harm of this irrigation on human health by means of epidemiological investigation and rnutation test.Based on the influences of this sewage irrigation on ecosystems,a cornprehensive prevention and control measure is put forward.

Key words: summer maize, nitrogen application period, key nitrogen metabolism enzyme, antioxidation characteristics.