海河流域农村非点源污染现状及空间特征分析

采用污染排放系数法估算了2008年海河流域农村生活源、畜禽分散养殖、农田化肥流失3个主要农村非点源COD、TN、TP和NH3-N 4种污染物的排放量,并对其排放强度和空间分布特征进行了分析.结果表明,海河流域农村非点源污染源排放COD、TN、TP和NH3-N总量分别为2435826, 3042079, 540568, 1798760t/a,平均排放强度分别为11.10, 13.97, 2.98, 8.28t/(km2·a).海河流域内河北省的3个农村非点源的4种污染物排放量均居首位,农村居民生活源对海河流域非点源污染贡献最大,是流域非点源污染控制最主要的对象;子牙河水系农村非点源污染物排放总量最大,而徒骇马颊河水系排放强度最大,是海河流域内污染最严重的水系,其首要非点源污染源是山东省的农村生活源.流域内非点源污染排放量和排放强度均呈现区域性分布,山区和平原区分别呈现出低污染等级和高污染等级.

Characteristics and spatial distribution of the rural non-point source pollution in Haihe River Basin

The emission characteristics of COD, TN, TP and NH3-N in Haihe River Basin which were discharged from three main kinds of rural non-point sources (NPS) including rural sewage, livestock and fertilizer loss were evaluated using pollution emission coefficient based on the national and provincial statistics in 2008, and the emission intensities and spatial distribution were analyzed. Total COD, TN, TP and NH3-N emission were 2435826, 3042079, 540568, 1798760 t/a, and emission intensities were 11.10, 13.97, 2.98, 8.28 t/(km2·a), respectively. The maximum NPS emission was from Hebei Province among the seven provinces in Haihe River Basin, and the rural sewage became the largest and top-priority controlling pollution sources among three kinds of NPS. Ziya River System was the largest receiving water of NPS pollutants among the nine river systems in Haihe River Basin. Tuhaimajia River System suffered from the largest NPS emission intensity and became the most heavily polluted river system, which was mainly resulted from the rural sewage discharged from Shandong Province. Moreover, the NPS pollutants emissions and emissions intensity were significantly regional distribution, the mountainous area presented a low pollution level and the plain area presented a high pollution levels.