安徽省非点源污染氮磷负荷时空变化及来源分析

Temporal and Spatial Changes and Source Analysis of Non-point Source Nitrogen and phosphorus Pollution Load in Anhui Province

探究安徽省非点源污染状况,对保障安徽省水生态安全以及安徽省的高质量发展具有重要意义。采用输出系数模型以及等标污染负荷法,估算安徽省2005-2020年氮磷污染负荷总量;结合GIS技术,分析其时空变化特征;在计算各污染源的等标污染负荷量以及等标污染贡献率的基础上,进一步探究安徽省非点源氮磷污染的主要污染源。结果表明:安徽省非点源氮磷污染存在很大的空间分异性,整体表现为皖北和皖中较高,皖南较低的特点,其中非点源氮磷污染负荷最高的是阜阳市,最低的为铜陵,前者约为后者的6~7倍;在时间上,在全省不同地区及各市,氮污染负荷总量整体呈上升趋势,而磷污染负荷变化则呈现不同的变化趋势;从类型看,非点源氮污染负荷的主要贡献源是土地利用,非点源磷污染负荷主要贡献源是畜禽养殖;从具体指标看,耕地为安徽省非点源氮的主要污染源,农村生活排放和耕地是安徽省非点源磷的主要污染源。

Exploring the non-point source pollution situation in Anhui Province is of great significance to ensuring water ecological security and achieving high-quality development in Anhui Province.The total nitrogen and phosphorus pollution load in Anhui Province from 2005 to 2020 was estimated using the output coefficient model and the equal standard pollution load method.By combining GIS technology,the spatiotemporal variation characteristics were analyzed.On the basis of calculating the equivalent pollution load and contribution rate of each pollution source,the main sources of non-point source nitrogen and phosphorus pollution in Anhui Province were further explored.The results showed that there was significant spatial differentiation in non-point source nitrogen and phosphorus pollution in Anhui Province,with the overall characteristics of higher levels in northern and central Anhui,and lower levels in southern Anhui.Fuyang City had the highest nitrogen and phosphorus pollution load of non-point sources,while Tongling had the lowest,The former is about 6-7 times that of the latter;In terms of time,at the provincial,regional,and municipal scales,the total nitrogen pollution load shows an overally upward trend,while the changes in phosphorus pollution load show different trends.The main contributor to non-point source nitrogen pollution load is land use,while the main contributor to non-point source phosphorus pollution load is livestock and poultry feeding.Farmland is the main source of non-point source nitrogen pollution in Anhui Province,while rural household emissions and farmland are the main sources of non-point source phosphorus pollution in Anhui Province.