Centre of Environmental Studies, University of Allahabad, Prayagraj, Uttar Pradesh, 211002, India.
Environ Monit Assess. 2024 Mar 2;196(4):336. doi: 10.1007/s10661-024-12499-0.
River nutrient enrichment is a significant issue, and researchers worldwide are concerned about phosphorus. The physicochemical characteristics and phosphorus (P) fractions of 36 sediment and water samples from the Ganga (Kanpur, Prayagraj, Varanasi) and Yamuna (Mathura, Agra, Prayagraj) rivers were examined. Among the physicochemical parameters, pH exceeded the permissible limit in Ganga and Yamuna River water and sediment samples. Electrical conductivity (EC) and alkalinity were within the permissible limits, whereas total nitrogen (TN) exceeded the limit in Yamuna water. The analysis of phosphorus fractions indicated the dominance of inorganic phosphorus (IP) (76% in Ganga and 96% in Yamuna) over organic phosphorus in both rivers, suggesting the mineralization and microbial degradation as major processes responsible for transforming OP to IP. The positive correlation of pH with IP, AP (apatite phosphorus), and NAIP (non-apatite inorganic phosphorus) explains the release of inorganic phosphorus under alkaline conditions. The correlation between total organic carbon (TOC), TN, and organic phosphorus (OP) indicated the organic load in the rivers from allochthonous and autochthonous sources. Phosphorus released from river sediments and the concentration of phosphate in overlying river water show a positive correlation, suggesting that river sediments may serve as phosphorus reservoirs. The average phosphorus pollution index (PPI) was above one in both rivers, with relatively higher PPI values observed in the Yamuna River, indicating the contamination of sediment with phosphorus, indicating the contamination of sediment with phosphorus. This study revealed variations in the P fractionation of the sediment in both rivers, primarily as a result of contributions from different P sources. This information will be useful for applying different mitigation techniques to lower the phosphorus load in both river systems.
河流富营养化是一个重大问题，全球研究人员都在关注磷。本研究对恒河（坎普尔、阿拉哈巴德、瓦拉纳西）和亚穆纳河（马图拉、阿格拉、阿拉哈巴德）的 36 个泥沙和水样的理化特性及磷形态进行了分析。在理化参数中，恒河和亚穆纳河水和泥沙样品的 pH 值超过了允许限值。电导率（EC）和碱度在允许范围内，而亚穆纳河水的总氮（TN）则超过了限值。磷形态分析表明，无机磷（IP）（恒河占 76%，亚穆纳河占 96%）在两条河中均占主导地位，超过有机磷，这表明矿化和微生物降解是将有机磷转化为无机磷的主要过程。pH 值与 IP、AP（磷灰石磷）和 NAIP（非磷灰石无机磷）呈正相关，这解释了在碱性条件下无机磷的释放。总有机碳（TOC）、TN 和有机磷（OP）之间的相关性表明，河流中的有机负荷来自异源和同源来源。河流沉积物释放的磷和上覆河水中磷酸盐的浓度呈正相关，这表明河流沉积物可能是磷的储存库。两条河的平均磷污染指数（PPI）均高于 1，亚穆纳河的 PPI 值相对较高，这表明沉积物受到磷的污染。本研究揭示了两条河泥沙中磷形态的变化，主要是由于不同磷源的贡献。这些信息将有助于应用不同的缓解技术来降低这两个河流系统的磷负荷。
