【作者】 王芳；

【导师】 贾德彬；

【作者基本信息】 内蒙古农业大学 ， 工程硕士（专业学位）， 2021， 硕士

【摘要】 岱海位于内蒙古自治区乌兰察布市境内,是自治区内重要的内陆湖之一,是环京津冀地区重要的生态屏障。近年来,由于岱海流域生态环境不断恶化,岱海湖泊出现了水量减少、湖面萎缩、水质污染等问题。为明确岱海湖水环境状况及重要污染物的时空分布规律,本文以岱海湖泊为研究对象,研究期从2019年4月至2020年10月,运用Arcgis插值分析、相关性分析和主成分分析等方法,对主要污染物的时空分布规律进行了分析,并评价了水质状况;运用综合营养状态指数法、模糊综合评价法、投影寻踪模型,评价了岱海湖泊的营养状况,结果如下:(1)岱海湖泊水体呈碱性,溶解氧、五日生化需氧量、氨氮等水质指标相对较好;高锰酸盐指数、化学需氧量、总磷、总氮的浓度较高。时间分布上大部分水质指标呈现出明显的季节性变化,空间分布上湖泊水质各季节差异较小,大多数指标间存在显著的相关性。(2)通过对岱海湖泊还原性污染物的相关指标作水质评价,结果表明综合污染指数时空差异显著,研究期内有11个月的综合污染指数P超过了2.00,属于重污染水质,占比57.9%;其余月份综合污染指数P介于1.00和2.00之间,属于中污染水质。2019年和2020年都表现为夏季7、8月污染较重。主成分分析法结果显示五日生化需氧量、高锰酸盐指数、总磷和化学需氧量是影响水质评价的主要因子。(3)通过运用综合营养状态指数法、模糊综合评价法和投影寻踪模型对岱海富营养化评价结果表明:岱海湖泊营养状态为轻度—中度富营养化。基于加速遗传算法的投影寻踪模型考虑各评价指标对营养状态的不同贡献,解决了权重赋值问题,很好的揭示了各水质指标之间的内在联系,使评价结果更加合理。更多还原

【Abstract】 Located in Ulanqab City,Inner Mongolia Autonomous Region,Daihai Lake is one of the important inland lakes in the region.It is an important ecological barrier around Beijing,Tianjin and Hebei.In recent years,the ecological environment of Daihai basin has been deteriorating,the water quantity has decreased,the lake surface has shrunk,and the water quality has deteriorated.In order to make clear the water environment condition of Daihai Lake and the temporal and spatial distribution law of important pollutants,based on the water quality data from April 2019 to October 2020,this paper comprehensively uses spatial interpolation by Arc GIS,correlation analysis,PCA and other statistical methods to deeply explore the temporal and spatial distribution of pollutants.The eutrophication status of Daihai Lake was evaluated by TLI,the fuzzy comprehensive evaluation,RAGA-PPE.The results show that:（1）Daihai Lake is alkaline as a whole,DO,BOD₅,NH₃-N and other water quality indicators are relatively good,The concentration of COD_Cr,COD_Mn,TP,TN were higher.Most of the water quality indicators showed obvious seasonal changes in time distribution.The spatial distribution of lake water quality has little difference among seasons.There is close correlations between the indicators.（2）The results showed that the comprehensive pollution index of Daihai Lake was significantly different in time and space.The comprehensive pollution index p of 11 months in the study period exceeded 2.00,which belonged to heavy pollution,accounting for 57.9%;In other months,the comprehensive pollution index p was between 1.00 and 2.00,which belonged to moderately polluted water quality.In both 2019 and 2020,the pollution is heavy in July and August.The results of principal component analysis showed that BOD₅,COD_Mn,TP、COD were the main factors affecting the water quality evaluation.（3）The eutrophication of Daihai Lake was evaluated by TLI,fuzzy comprehensive evaluation method and RAGA—PPE.The results showed that the eutrophication of Daihai Lake was mild to moderate.The projection pursuit model considers the different contribution of each evaluation index to the nutritional status,solves the problem of weight assignment,and reveals the internal relationship between each water quality index,which makes the evaluation results more reasonable.更多还原