GIS支持下的凡河流域农业非点源污染物时空特征分析

为了解铁岭县凡河流域农业非点源污染现状,本文以铁岭县多年乡镇统计报表为基础,结合输出系数法及源强系数法分析了凡河流域2007-2009年四种农业非点源污染物排放量及其排放强度的时空分布特征。结果表明:(1)流域内农业非点源污染物排放总量呈持续上升趋势,总氮、总磷、化学需氧量及氨氮的平均排放量为3174.5、361.4、16624.5和3980.3t/a;(2)流域内主要污染物为化学需氧量,主要污染源为畜禽养殖;(3)污染物排放总量及强度空间上大致呈中、西部高,东部低的特点,李千户乡及铁岭市区为主要污染区域。为有效地控制凡河流域农业非点源污染,当地政府应把重点放在畜禽粪便及居民生活垃圾的处理方式上。

Analysis of spatial-temporal characteristic of agricultural non-point source pollution in Fanhe river basin based on GIS

Based on long-term statistical reports of Tieling county and combined export coefficient model and source coefficient method, this paper analyzed the discharge and temporal-spatial characteristics of non-point source pollutants (NPS) in Fanhe river from 2007-2009 in order to understand the situation of the pollution.Results showed that the discharge of four types of agricultural NPS have a rising trend in this basin,the average emissions of total nitrogen, total phosphorus, chemical oxygen demand and ammonia nitrogen are 3174.5, 361.4, 16624.5 and 3980.3 tons per year;the chemical oxygen demand is the major pollutant and animal manure is the major source in Fanhe river; the spatial distribution of NPS discharge and their discharge intensity is high in the center and west, and is low in the east, Liqianhu towns and Tieling downtown are the major pollution regions in Fanhe river. It is necessary for the local government to focus on the treatment of livestock manure and household waste in order to control the agricultural non-point source pollution more efficiently.