于丹+刘琼琼+邵晓龙+刘红磊+田晶+张青

摘要：针对北运河下游流域设施农业快速发展、化肥农药施用量剧增、肥料利用效率不高的特点，选取北运河下游典型设施农田—北辰双街农业种植园作为研究区，结合其降水径流形成特征，分析设施农业非点源污染流失特征。结果表明，研究区降雨的流量过程线呈正态单峰型特征，降雨的径流过程都表现为陡涨、陡落;随着降雨径流的产生和径流流量的增加，径流污染物的浓度快速升高，达到峰值后迅速下降，后期较均匀稳定;污染物浓度的峰值提前于径流的峰值，在整个径流污染过程中整体表现为初期径流中污染物的浓度高于后期径流中污染物的浓度;研究区年污染负荷量TN为990.8 kg、TP为17.19 kg、NH4+-N为304.17 kg、NO3-N为469.72 kg、COD为5 879.65 kg。从污染负荷数值来看，大棚种植区的年平均氮磷释放量远小于露天种植方式。

关键词：北运河下游流域;设施农田;氮磷流失;污染负荷;

中图分类号：S157.1        文献标识码：A        文章编号：0439-8114（2015）23-5881-06

DOI：10.14088/j.cnki.issn0439-8114.2015.23.021

Characteristics of Nitrogen and Phosphorus Loss of Facility Farmland in the Downstream of the North Canal River Watershed

YU Dan1，LIU Qiong-qiong1，SHAO Xiao-long1，LIU Hong-lei1，TIAN Jing2，ZHANG Qing2

（1.Tianjin Environmental Protection Science Research Institute，Tianjin 300191，China; 2.Tianjin Professional College，Tianjin 300191，China）

Abstract： Beichen Shuangjie Agricultural Demonstrational Park， a typical facility farmland in the downstream of North Canal River， was selected as the research area. The formation mechanism of non-point source pollution and the characteristics of nitrogen and phosphorus loss of the typical facility farmland were analyzed by the formation characteristics of rainfall-runoff in this park. Results showed that the discharge curve of the rainfall in the research area was normally unimodal and its runoff process showed a steep rise and fall. With the production of rainfall runoff and an increase in runoff， the concentrations of runoff pollutant rose to a peak rapidly and then fell rapidly， later became uniform and stable. The peak of pollutant concentrations was ahead of that of runoff， showing that the pollutant concentrations in early runoff was higher than that in the late runoff throughout the process of the runoff pollution.A pollution load accounting model for greenhouse region was presented using an improved export coefficient method. Results showed that total nitrogens， total phosphorus， ammonium nitrogen， nitrate nitrogen and COD release were 990.80，17.19，304.17，469.72，5 879.65 kg/a， respectively. With the data of pollution load， the nitrogen and phosphorus release in facility farmland system was much less than that in open farmland systems.

Key words： North Canal River watershed; facility farmland; nitrogen and phosphorus loss; pollution load

氮、磷是生物体必需元素，同时也是引起水体富营养化的主要影响因素[1]。近年来，随着经济发展，人类活动日益剧烈，中国河流水体中营养元素质量浓度呈上升趋势。营养盐质量浓度上升会导致河流水体富营养化风险增加，这将成为河流水环境治理的重要问题之一[2]。endprint

海河水系在全国七大水系中污染状况最为严重，总体为重度污染，尤其是氮磷污染严重，若未能得到及时有效的控制，将严重制约华北地区的可持续发展，造成重大及难以逆转的后果[3]。……