秦皇岛水质时空分布特征及归因分析

为分析秦皇岛市水环境质量的时空变化特征,本研究收集秦皇岛市17个监测断面2017年1-12月逐月COD、NH+4-N、TP、高锰酸盐指数监测数据,运用单因子评价法和主成分分析法评价水环境质量,结合土地利用类型进行归因分析。结果显示:①时间上,研究区污染物浓度全年表现为春季>冬季>夏季>秋季,春、冬季受TP污染严重,夏、秋季污染相对较低,汛期、非汛期水质差异不显著,汛期污染物主要为NH+4-N,非汛期为TP;②空间上,64.7%的监测断面水质为劣Ⅴ类,其中减河、饮马河污染相对严重,下游沿海诸河污染程度大于上游山区;③子流域污染物浓度与土地利用结构的相关性表明居民用地等人类活动用地的增加是造成研究区内水体污染的主要原因,反之,林地、草地等自然用地面积的增加有助于缓解水体污染。

Spatial and Temporal Distribution Characteristics and Evaluation Analysis of Surface Water Quality in Qinhuangdao City

In order to analyze the temporal and spatial variation characteristics of water environment quality in Qinhuangdao City,the monitoring data of COD,NH+4-N,TP and permanganate index of 17 monitoring sections in Qinhuangdao City were collected monthly in 2017.The water environment quality is evaluated by single factor evaluation and principal component analysis,and the causes of pollution are analyzed by combining the land use structure.The results show that:①In time,TP and NH+4-N pollution is serious in spring and winter,but relatively low in summer and autumn,and the water quality in flood season is better than that in non-flood season on the whole.②In space,64.7%of the monitoring sections'water quality are inferior typeⅤ.The pollution of Jian River,Yinma River and Tang River are relatively serious,and the pollution degree of downstream coastal rivers is greater than that of upstream rivers.③The correlation between pollutant concentration and land use structure shows that human land use is the main cause of water pollution in the study area,and the increase in natural land area such as woodland and grassland is helpful to alleviating water pollution.