博斯腾湖水质空间变化特征及评价

Characteristics and evaluation of spatial variation of water quality in Bosten lake

利用空间插值法、主成分分析法、内梅罗污染指数法分析及评价博斯腾湖水质污染状况。结果表明,博斯腾湖水质指标总氮(TN)、总磷(TP)、氨氮(NH_(3)-N)、高锰酸盐指数(COD_(Mn))、悬浮物(SS)及浊度具有明显的空间差异性,湖西南岸和湖东北岸浓度高于湖中心,溶解氧(DO)自东向西呈逐渐递减趋势,pH值由湖西南岸向湖中心及北岸中部地带呈递增态势;各水质指标间存在极强的相关性,DO与TN、TP、NH_(3)-N、COD_(Mn)及浊度呈显著负相关,TP与TN、NH_(3)-H、COD_(Mn)、浊度,NH_(3)-N与COD_(Mn)和浊度,COD_(Mn)与浊度呈显著正相关,湖泊受DO、TN、TP、NH_(3)-N有机物污染程度高,湖区各水岸污染程度从大到小依次为,湖南岸>湖北岸>湖西岸>湖中心>湖东岸;污染评价结果显示,博斯腾湖东岸、湖中心和湖西岸属轻污染,湖北岸和湖南岸属中污染。水质空间变化特征能够指出主要污染因子,直观反映湖泊水质污染状况,为干旱区内陆湖泊水资源保护和治理提供参考依据。

Methods such as spatial interpolation,principal component analysis,and the Nemero pollution index were used to analyze and evaluate the water pollution of Bosten lake.According to the result,the total nitrogen(TN),total phosphorus(TP),ammonia nitrogen(NH_(3)-N),potassium permanganate index(COD_(Mn)),suspended solids(SS)and turbidity of Bosten lake water quality indicators indicated an obvious spatial difference,with the concentration of the southwest shore and the northeast shore of the lake being higher than that of central lake.the dissolved oxygen(DO)showed decreasing from east to west,and the pH value increasing from the southwest shore of the lake to the center and the middle zone of the north shore.There was a strong correlation between the water quality indicators.The DO and TN,TP,NH_(3)-N,COD_(Mn) and turbidity were significantly negatively correlated while TP and TN,NH_(3)-H,COD_(Mn),turbidity,NH_(3)-N and COD_(Mn) and turbidity.COD_(Mn) and turbidity were significantly positively correlated.Organic matters such as DO,TN,TP,NH_(3)-N polluted the waterfront in the lake area heavily,with the pollution level of the south shore being the highest,then the north shore,the west shore,lake centre,followed by the east shore.The results of the pollution assessment showed that the east shore,centre and west bank of Bosten lake were lightly polluted with class Ⅲ water quality,and the north shore and the south shore of the lake were medium pollution with class Ⅳ water quality.The spatial variation characteristics of water quality could reflect the main pollution factors and the pollution level of lake water quality,thus providing a reference for the protection and treatment of water resources in inland lakes in arid areas.