稻田氮素流失规律测坑研究

通过测坑试验，研究了稻田水中氮素的变化动态、渗漏流失规律。结果表明，施肥后田水中氮素的浓度有逐日递减的趋势，但各种形态氮素的变化趋势有所不同，铵氯在第二天就减少了75％；不同施肥期氮素的渗漏流失量以基肥期为最大；在前茬为草莓的情况下以NO^-3-N渗漏流失为主；NO^-3-N作为氮素在土壤中淋失移动的主要形态将成为施用氮肥造成地下水污染的重要来源。

Study of the Testing-hole on the Nitrogen Loss in the Rice Field

Based on the testing hole experimentation, this paper studied on the transformation process, leakage loss of nitrogen in the rice field water. The result showed that the concentration of nitrogen in the rice field water was decreased day by day after fertilization, however the transformation trend of diversified form of nitrogen was different, for instance, ammonium reduced as much as 75 %on the next day. The leakage quantity of nitrogen in ground fertilizer period was maximal at different fertilization periods. Leakage loss of NO-3 N was the main loss of nitrogen when the former stubble plant was strawberry. As the main form of nitrogen in soil leakage movement , NO-3 N would be important source to pollute the groundwater after fertilization.