【作者】 金洁； 杨京平；

【Author】 Jin Jie,Yang Jingping(Ecological Institute of Life Science College Zhejiang University ,Hangzhou 310029)

【机构】 浙江大学生命科学学院生态研究所；

【摘要】 本试验通过自行设计的渗漏计研究在控水灌溉条件下稻田不同氮肥处理的氮素淋失的动态规律,结果表明:在水稻整个生育期间,渗漏水中铵态氮,硝态氮保持较低的浓度,均小于1mg/L,但对硝态氮而言,仍是氮素淋失的主要类型。从总的趋势来看,渗漏水中氮素浓度随着施肥量的增加而增加。每次施肥后,不同处理渗漏水中的NO3--N浓度均表现为短期内迅速上升、后期逐渐下降的趋势,其中NH4+-N浓度与NO3--N的消长规律相似,但表现出峰值超前的特征。而且各小区渗漏计中NH4+-N、NO3--N及TN累积渗漏量与施肥量之间存在显著相关性,R2分别达到0.933*,0.984**和0.982**。另外从环境和经济角度考虑,建议在土壤质地粘重、基础肥力较高的水稻土施肥量控制在75-150kg/hm2为宜,控制氮素淋失主要时期为施肥后一周内,特别在基肥施后尤为关键。更多还原

【Abstract】 Using a lysimeter self-designed, the dynamic variation of nitrogen leaching and its amount loss in paddy field were studied under 5 different Nitrogen treatments with controlled water irrigation systems in 2003. The result showed that NH4+-N and NO3--N concentration of the leakage water remained at a very low level during the whole growing Period of rice,which were lower than 1mg/L. The main leaching form in the leakage water was dominated by NO3--N. Nitrogen loss from leaching in this experiment increased gradually with fertilizer applications increase. After the application of fertilizer for each time, the concentration of NO3--N in different treatments increased rapidly during a short period and then decreased gradually. The concentration dynamic patterns Of NH4+-N had the similar trends and regularity as N03--N, but it showed the peak concentration value Of NH4 +-N exceeded that Of N03--N .There were significant correlation between nitrogen fertilizer applied and the accumulative amount of NH4+-N ,N03--N and TN of the leakage water in the lysimeter of different plots and the coefficient is 0.933*,0.984**,0.982** respectively. Based on the point of economy and environment consideration, it is suggested that 75-150 kg/hm2 with N application in Paddy field with sticky and higher soil fertility could be reasonable for better yield and reducing the N leaching. The period within a week after the N application was critical time to control N leaching from paddy field, especially for the first N application in Paddy field.更多还原