自然降雨条件下淮北平原农田氮素流失特征研究  

Study on Nitrogen Loss Characteristics of Farmland in Huaibei Plain under Natural Rainfall Conditions

作　　者：杨继伟[1,2] 袁宏伟 袁先江[1,2] 李如忠 曹秀清[1,2] YANG Ji-wei1,2, YUAN Hong-wei1,2, YUAN Xian-jiang1,2(1.Water Resources Research Institute of Anhui Province and Huaihe Riv-er Commission, Ministry of Water Resources, Bengbu,Anhui 233000;2.Key Laboratory of Water Conservancy and Water Resources of AnhuiProvince, Bengbu,Anhui 23300)

机构地区：[1]安徽省水利部淮河水利委员会水利科学研究院,安徽蚌埠233000 [2]水利水资源安徽省重点实验室,安徽蚌埠233000 [3]合肥工业大学资源与环境工程学院,安徽合肥230009

出　　处：《安徽农业科学》2018年第22期65-68,共4页Journal of Anhui Agricultural Sciences

基　　金：国家青年科学基金项目(51409002);安徽省水利科技计划项目(slkj201603);安徽省水利科学研究院青年创新基金项目(sk201708)

摘　　要：[目的]研究自然降雨过程中农田氮素径流流失特征。[方法]基于淮北平原区1次典型的自然降雨,分析降雨强度、径流量及排水中TN、PN、NH_4^+-N和NO_3^--N的质量浓度变化。[结果]自然降雨条件下,降雨强度和径流量变化趋势基本一致,但产流时间较降雨时间以及径流量较降雨强度的变化均有一定滞后效应;随着径流量增大,排水中TN、PN和NH_4^+-N的质量浓度快速增大,且达到峰值的时间较径流峰值时间提前,峰值过后三者质量浓度快速下降,降雨停止后随着径流减少TN趋于稳定,PN和NH_4^+-N继续降低,NO_3^--N质量浓度与径流量呈反向变化特征;随着雨强和径流量的变化3种形态氮素比例动态变化,且降雨时颗粒态氮大于溶解态氮,降雨停止后PN和可溶态NH_4^+-N减少,可溶态NO_3^--N增加;相关性分析表明,降雨强度与径流量、NH_4^+-N、PN和TN呈正相关关系,与NO_3^--N呈负相关关系;整个径流过程TN、PN、NH_4+^-N和NO_3^--N质量浓度均值分别为11.50、6.58、2.11和2.88 mg/L,均超出了地表水Ⅴ类水的标准。[结论]自然降雨径流过程中农田排水给周围水体带来较大的环境风险,该研究为该区域氮素流失特征研究及面源污染控制提供理论基础。[Objective] The research aimed to study the characteristics of nitrogen runoff loss in farmland during natural rainfall.[Method] Basedon a typical natural rainfall process in Huaibei Plain area, the rainfall intensity,runoff and the mass concentration of TN,PN,NH4＋-N andNO3--N in drainage was analyzed.[Result]Under the condition of natural rainfall, the trend of runoff was in accord with the trend of the rainfallintensity basically, but the change of runoff time and runoff had a certain lag effect compared with the change of rainfall intensity.With increaserunoff, the mass concentration of TN, PN, and NH4＋-N increases rapidly, that the peak time of nitrogen mass concentration was earlier than thepeak time of runoff, and after the peak three mass concentration reduced rapidly.As the runoff decreased TN tends to be stable, the PN andNH4＋-N continue to reduce when the rain stopped.However the change of NO3--N reverse to the change of runoff.With the change of rainfall in-tensity and runoff, the percentage of nitrogen in the three morphologies changed dynamically, and the grainy nitrogen was larger than the dis-solved nitrogen during the rainfall.Grain nitrogen and soluble NH4＋-N decreased and soluble NO3--N increased after rainfall stopped.Correlationanalysis showed that rainfall intensity was positively correlated with runoff,TN, PN,NH4＋-N and negatively correlated with NO3--N.The averagemass concentration of TN, PN, NH4＋-N and NO3--N were 11.50, 6.58, 2.11 and 6.58 mg / L respectively, which go beyond the standard of thesurface water Ⅴclass.[Conclusion]In the course of natural rainfall runoff, agricultural drainage brings great environmental risks to surroundingwater.This paper provides a theoretical basis for the study of nitrogen loss characteristics and regional non-point source pollution control.

关 键 词：自然降雨 径流 农田 氮素流失 面源污染 

分 类 号：S181[农业科学—农业基础科学]