Abstract:
Understanding heavy metals in rivers is crucial, as their presence and distribution impact water quality, ecosystem health, and human well-being. This study examined the presence and levels of nine heavy metals (Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn) in 16 surface water samples along the Chao Phraya River, identifying Fe, Mn, Zn, and Cr as predominant metals. Although average concentrations in both rainy and dry seasons generally adhered to WHO guidelines, Mn exceeded these limits yet remained within Thailand\'s acceptable standards. Seasonal variations were observed in the Chao Phraya River, and Spearman\'s correlation coefficient analysis established significant associations between season and concentrations of heavy metals. The water quality index (WQI) demonstrated varied water quality statuses at each sampling point along the Chao Phraya River, indicating poor conditions during the rainy season, further deteriorating to very poor conditions in the dry season. The hazard potential index (HPI) was employed to assess heavy metal contamination, revealing that during the dry season in the estuary area, the HPI value exceeded the critical threshold index, indicating the presence of heavy metal pollution in the water and unsuitable for consumption. Using the species sensitivity distribution model, an ecological risk assessment ranked the heavy metals\' HC5 values as Pb > Zn > Cr > Cu > Hg > Cd > Ni, identifying nickel as the most detrimental and lead as the least toxic. Despite Cr and Zn showing a moderate risk, and Cu and Ni posing a high risk to aquatic organisms, the main contributors to ecological risk were identified as Cu, Ni, and Zn, suggesting a significant potential ecological risk in the Chao Phraya River\'s surface water. The results of this study provide fundamental insights that can direct future actions in preventing and managing heavy metal pollution in the river ecosystem.
摘要:
了解河流中的重金属至关重要,因为它们的存在和分布会影响水质,生态系统健康,和人类福祉。这项研究检查了9种重金属(Cd,Cr,Cu,Fe,Hg,Mn,Ni,Pb,和锌)在湄南河沿岸的16个地表水样品中,识别Fe,Mn,Zn,和Cr作为主要金属。尽管雨季和旱季的平均浓度通常符合世卫组织的准则,锰含量超过了这些限值,但仍在泰国可接受的标准范围内。在湄南河中观察到了季节性变化,Spearman的相关系数分析在季节和重金属浓度之间建立了显着的关联。水质指数(WQI)显示了湄南河沿岸每个采样点的不同水质状况,表明雨季条件差,在旱季进一步恶化到非常恶劣的条件。危险潜在指数(HPI)用于评估重金属污染,揭示了在河口地区的旱季,HPI值超过临界阈值指数,表明水中存在重金属污染,不适合食用。使用物种敏感性分布模型,生态风险评估将重金属的HC5值排序为Pb>Zn>Cr>Cu>Hg>Cd>Ni,确定镍是最有害的,铅是毒性最小的。尽管Cr和Zn显示出中等风险,铜和镍对水生生物构成高风险,生态风险的主要贡献者是铜,Ni,Zn,这表明湄南河地表水存在显著的潜在生态风险。这项研究的结果提供了基本见解,可以指导未来在预防和管理河流生态系统中重金属污染方面的行动。