Qadir Abdul, Malik Riffat Naseem, Husain Syed Z
Environmental Biology Laboratory, Department of Plant Sciences, Quaid-i-Azam University, Islamabad, PO 4600, Pakistan.
Environ Monit Assess. 2008 May;140(1-3):43-59. doi: 10.1007/s10661-007-9846-4. Epub 2007 Jul 31.
This study reports the spatio-temporal changes in water quality of Nullah Aik, tributary of the Chenab River, Pakistan. Stream water samples were collected at seven sampling sites on seasonal basis from September 2004 to April 2006 and were analyzed for 24 water quality parameters. Most significant parameters which contributed in spatio-temporal variations were assessed by statistical techniques such as Hierarchical Agglomerative Cluster Analysis (HACA), Factor Analysis/Principal Components Analysis (FA/PCA), and Discriminant Function Analysis (DFA). HACA identified three different classes of sites: Relatively Unimpaired, Impaired and Less Impaired Regions on the basis of similarity among different physicochemical characteristics and pollutant level between the sampling sites. DFA produced the best results for identification of main variables for temporal and spatial analysis and separated eight parameters (DO, hardness, sulphides, K, Fe, Pb, Cr and Zn) that accounted 89.7% of total variations of spatial analysis. Temporal analysis using DFA separated six parameters (E.C., TDS, salinity, hardness, chlorides and Pb) that showed more than 84.6% of total temporal variation. FA/PCA identified six significant factors (sources) which were responsible for major variations in water quality dataset of Nullah Aik. The results signify that parameters identified by statistical analyses were responsible for water quality change and suggest the possibility of industrial, municipal and agricultural runoff, parent rock material contamination. The results suggest dire need for proper management measures to restore the water quality of this tributary for a healthy and promising aquatic ecosystem and also highlights its importance for objective ecological policy and decision making process.
本研究报告了巴基斯坦杰纳布河支流艾克河水质的时空变化。2004年9月至2006年4月，按季节在七个采样点采集溪水样本，并对24项水质参数进行了分析。通过层次聚类分析（HACA）、因子分析/主成分分析（FA/PCA）和判别函数分析（DFA）等统计技术，评估了导致时空变化的最重要参数。HACA根据不同采样点之间不同理化特征和污染物水平的相似性，确定了三类不同的区域：相对未受损区、受损区和受损较轻区。DFA在识别用于时空分析的主要变量方面取得了最佳结果，并分离出八个参数（溶解氧、硬度、硫化物、钾、铁、铅、铬和锌），这些参数占空间分析总变化的89.7%。使用DFA进行的时间分析分离出六个参数（电导率、总溶解固体、盐度、硬度、氯化物和铅），这些参数显示出超过84.6%的总时间变化。FA/PCA确定了六个重要因素（来源），这些因素是艾克河水质数据集中主要变化的原因。结果表明，统计分析确定的参数是水质变化的原因，并表明存在工业、城市和农业径流、母岩物质污染的可能性。结果表明迫切需要采取适当的管理措施来恢复这条支流的水质，以建立一个健康且有前景的水生生态系统，同时也凸显了其对于客观生态政策和决策过程的重要性。
