湖库型水源地富营养状况及土地利用对水质的影响

Effects of Eutrophic Status and Land-use Types on Water Quality in Lake and Reservoir Water Source Reserves

  • 摘要: 以滇东南8个湖库型饮用水源地为研究对象,在2019年5—7月水源地水质常规监测数据的基础上,结合一、二级保护区内耕地、园地和住宅用地3种土地利用类型,采用相关性分析和冗余分析,探讨保护区不同土地利用方式对水源地水环境质量的影响。结果表明:红旗水库、合作水库采样周期内未达到水质考核标准(Ⅱ类水),超标因子为总氮和总磷,5—6月水质量要明显优于7月。8个水源地水体处于贫营养化状态,DO为主要驱动因子,BOD5、TN为潜在污染项目。住宅用地占比与TN、TP间呈显著正相关,与园地也是正相关关系,表明农业活动是影响水源地水环境质量的主要因素。RDA分析中园地与TP、化学需氧量均在同一象限,与溶解氧则呈显著负相关。合理调整水源地保护区土地利用结构和空间布局,是湖库型水源地面源污染控制的有效措施。

     

    Abstract: Taking 8 typical lake & reservoir water source reserves in southeast Yunnan as the study area. Based on the water quality data from May to July 2019, combined with 3 land use types of cultivated land, garden land and residential land in the first and second grade protected areas, the influence of different land use types on the quality of water sources in protected areas was explored by correlation analysis, redundancy analysis(RDA). The results showed that Hongqi and Hezuo reservoir did not meet assessment standard(class II water) within sampling period, and the excess factors were TN and TP. The water quality in May and June was better than July. On the whole, all drinking water sources were in poor eutrophication stage. DO was the main driving factor, BOD5, TN was the potential pollutionindex. There was a significant positive correlation between Res%(percentage of residential land area), Gar%(percentage of garden area) and TN, TP. This indicates agricultural activities are the main factor affecting the water quality of water sources reserve. In RDA analysis, the Gar% and TP or CODCr parameters are in the same quadrant, but negatively correlate with DO. Reasonable adjustment of landscape structure and layout has great significance for control non-point source pollution.

     

/

返回文章
返回