天山森林地表水污染及其与土壤重金属含量的关系

Pollution characteristics of forest surface water and the relationship with the soil heavy metal content in Tianshan

为探究新疆天山森林地表水污染特征,以天山北麓中段雪岭云杉林为靶区,分析溪流地表水污染特征,结合相关性分析和主成分分析对地表水污染来源进行探讨,并运用冗余分析探究pH值、总磷(TP)、总氮(TN)、氨氮(NH3-N)、硝酸盐氮(NO3-N)、高锰酸盐指数(CODMn)、化学需氧量(COD)7项地表水污染指标与砷(As)、汞(Hg)、铅(Pb)、镉(Cd)、铬(Cr)、铜(Cu)、锌(Zn)、铝(Al)8种土壤重金属元素的相关关系。结果表明:桦树沟溪流地表受高锰酸盐、TN和TP污染;小渠子和甘沟溪流地表水为TN和TP污染。地表水污染特征评价表明,溪流地表水整体水质为劣V类,水体呈富营养化。主成分分析得出,森林地表水污染指标中TN和NH3-N呈极显著相关(P≤0.01),COD Mn与COD、TN呈显著相关(P≤0.05),TP为水质恶化的污染源。冗余分析表明,Cu、Hg、Cd、Al四种森林土壤重金属元素是森林水质资源的重要影响因子,影响次序为Cu>Hg>Cd>Al,其中Cu对水资源污染指标影响最大。森林地表水污染特征研究是森林资源状况研究的基础,对水资源的污染防治以及区域可持续发展具有重要意义。

To explore the characteristics of forest surface water pollution in Tianshan forest,Xinjiang,a target area of Picea schrenkiana forest in the middle of the northern foot of Tianshan Mountain was selected to analyze the characteristics of stream surface water pollution.Correlation and principal component analyses were used to explore the source of the surface water pollution.Redundancy analysis was used to explore the correlation between seven water pollution indexes,including the pH,total phosphorus(TP),total nitrogen(TN),ammonia nitrogen(NH3-N),nitrate nitrogen(NO3-N),permanganate index(CODMn),and chemical oxygen demand(COD),and eight soil pollution indexes,including those of arsenic(As),mercury(Hg),lead(Pb),cadmium(Cd),chromium(Cr),copper(Cu),zinc(Zn),and aluminum(Al).The results showed that:the surface water pollution was characterized by permanganate,TN,and TP pollution in Huashugou,while the surface water pollution in Xiaoquzi and Gangou was characterized by TN and TP pollution;the evaluation of the surface water pollution characteristics indicated that the overall water quality of the stream surface water was poor,and the water was undergoing eutrophication;the results of the principal component analysis showed that the TN and NH3-N were significantly correlated(P≤0.01),CODMn was significantly correlated with the COD and TN(P≤0.05),and the total phosphorus was the pollution source causing the deterioration in the water quality;the redundancy analysis showed that four heavy metals in the forest soil,Cu、Hg、Cd、and Al,were the important influencing factors affecting forest water quality resources,with an order of Cu>Hg>Cd>Al.Among these heavy metals,Cu had the greatest impact on the water pollution indicators.Research concerning the characteristics of forest surface water pollution is the basis for researching forest resources,which is of great significance for the prevention and control of the pollution of water resources and regional sustainable development.