北運河下游流域設施農田氮磷流失特征及污染負荷研究

于丹+劉瓊瓊+邵曉龍+劉紅磊+田晶+張青

摘要：針對北運河下游流域設施農業快速發展、化肥農藥施用量劇增、肥料利用效率不高的特點，選取北運河下游典型設施農田—北辰雙街農業種植園作為研究區，結合其降水徑流形成特征，分析設施農業非點源污染流失特征。結果表明，研究區降雨的流量過程線呈正態單峰型特征，降雨的徑流過程都表現為陡漲、陡落;隨著降雨徑流的產生和徑流流量的增加，徑流污染物的濃度快速升高，達到峰值后迅速下降，后期較均勻穩定;污染物濃度的峰值提前于徑流的峰值，在整個徑流污染過程中整體表現為初期徑流中污染物的濃度高于后期徑流中污染物的濃度;研究區年污染負荷量TN為990.8 kg、TP為17.19 kg、NH4+-N為304.17 kg、NO3-N為469.72 kg、COD為5 879.65 kg。從污染負荷數值來看，大棚種植區的年平均氮磷釋放量遠小于露天種植方式。

關鍵詞：北運河下游流域;設施農田;氮磷流失;污染負荷;

中圖分類號：S157.1 ? ? ? ?文獻標識碼：A ? ? ? ?文章編號：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、磷是生物體必需元素，同時也是引起水體富營養化的主要影響因素[1]。近年來，隨著經濟發展，人類活動日益劇烈，中國河流水體中營養元素質量濃度呈上升趨勢。營養鹽質量濃度上升會導致河流水體富營養化風險增加，這將成為河流水環境治理的重要問題之一[2]。endprint

海河水系在全國七大水系中污染狀況最為嚴重，總體為重度污染，尤其是氮磷污染嚴重，若未能得到及時有效的控制，將嚴重制約華北地區的可持續發展，造成重大及難以逆轉的后果[3]。……