摘要
研究氮磷在底泥、上覆水以及两者间交换介质-间隙水三者之间的迁移转化规律对控制农业面源污染具有重要科学意义。本研究对降雨和无降雨情况下氮磷在沟渠底泥、间隙水和上覆水间的迁移转化规律进行了分析;同时,对扫描电子显微镜(SEM)下底泥颗粒的微观形貌进行了观测。结果表明:在水稻生长前期氮磷被吸附贮存在底泥中,中后期被再次释放出来;在整个水稻生长期内,间隙水的总氮、总磷浓度约为上覆水的3.1和6.5倍,氮主要以NH_4^+-N形式存在;在降雨过程中,沟渠底泥成为氮磷释放的源,NH_4^+-N为氮的主要迁移形态,上覆水中NH_4^+-N逐渐向NO_3^--N转化,颗粒态氮磷对TN、TP流失有较大影响;沟渠底泥颗粒表面粗糙、具有一定的微孔结构,为底泥吸附氮磷提供了条件。
Study on the migration and transformation of nitrogen and phosphorus among the sediment-inter- stitial water-overlying water can contribute to grasp the interception mechanism of nitrogen and phosphorus in farmland drainage ditch. In this paper, the migration and transformation of nitrogen and phosphorus through the three were studied and the sediment morphology was tested by scanning electron microscope （SEM）. The results show that： the nitrogen and phosphorus are adsorbed and stored in the sediment in the early stage of rice growth, and the nitrogen and phosphorus are released in the later ice growth; during the entire rice growth, the concentration of nitrogen and phosphorus in the interstitial water arc about 3.1 and 6.5 times the overlying water, which the NH4^-N as the main nitrogen form of storage; in the process of rainfall, the ditch sediment as the source of nitrogen and phosphorus which provide the nitrogen and phosphorus in the interstitial water gradually migrate to the overlying water, NHU-N gradually change to NO3--N, and the granular TN and TP had a great influence on the loss of TN and TP in the overlying wa- ter; and the surface of sediment particles is rough and has a pore structure, that is conducive to the ad- sorption of nitrogen and phosphorus.
出处
《水利学报》
EI
CSCD
北大核心
2017年第12期1410-1418,共9页
Journal of Hydraulic Engineering
基金
国家自然科学基金创新研究群体科学基金(51621092)
天津市应用基础与前沿技术研究计划(16JCYBJC23100)
关键词
农田排水沟渠
底泥
间隙水
上覆水
SEM
氮磷
ditch
sediment
interstitial water
overlying water
SEM
nitrogen and phosphorus
作者简介
王晓玲（1968-），女，重庆人，博士，教授，博士生导师，主要从事水环境治理及水环境数值模拟研究。E—mail：wangxl@tju．edu．cn
