基于Mann-Kendall检验分析里畈水库水质变化趋势研究

Analysis on Variation Trend of Water Quality Based on Mann-Kendall Test in Lifan Reservoir

根据临安市环境监测站2006-2016年里畈水库的监测数据,采用Mann-Kendall非参数统计检验法对里畈水库水质变化趋势进行分析。趋势分析表明,pH和溶解氧的值总体呈上升趋势,氨氮、总磷和高锰酸盐的值总体呈下降趋势,11年间里畈水库水质总体呈上升趋势;总磷是影响里畈水库水质类别的主要因素。对各参数突变次数及时间分析表明,总磷突变最为复杂;溶解氧和氨氮变化趋势最为简单;水质突变主要集中在2007年和2016年。

According to the monitoring data from Lin＇an environmental monitoring station in Litan reservoir, the water quality trend of Lifan Reservoir from 2006 to 2016 were analyzed by using the Mann - Kendall method. The analysis shows that pH and DO had an increasing trend, while NH3 - N, TP and CODMn presented a decreased trend, indicating that the water quality of Li- fan reservoir had improved over the past eleven years. Total phosphorus was the main factor affecting the water quality of the reser- voir. The mutation frequency and time of every parameter were analyzed, which showed that abrupt water changes mainly occurred in years 2007 and 2016. The changes of total phosphorus were most complex, while the change of DO and NH3 - N was easiest.