Department of Environmental Science, School of Earth Sciences, Central University of Rajasthan, Bandar Sindri, Ajmer, Rajasthan, India.
National Institute of Urban Affairs, Ministry of Housing and Urban Affairs, Delhi, India.
Sci Rep. 2022 Jul 27;12(1):12774. doi: 10.1038/s41598-022-15422-0.
The present research has been performed to analyze the chemical behavior of rainwater of the Shaune Garang catchment (32.19° N, 78.20° E) in the Baspa basin, located at a high elevation (4221 m above mean sea level) in the Himachal Himalaya, India. During the study period, sixteen rainwater samples were collected from the Shaune Garang catchment at five different sites. The volume-weighted mean (VWM) pH value of rainwater ranged between 4.59 and 6.73, with an average value of 5.47 ± 0.69, indicating the alkaline nature of rainfall. The total ionic strength in the rainwater ranged from 113.4 to 263.3 µeq/l with an average value of 169.1 ± 40.4 µeq/l. The major dominant cations were Ca (43.10%) and Na (31.97%) and anions were Cl (37.68%), SO (28.71%) and NO (23.85%) in rainwater. The ionic ratios were calculated among all the ions. The fraction of (NO +Cl) with SO was measured as 2.3, which specifies sour faces of rainwater due to HNO, HSO, and HCl. A multivariate statistical assessment of rainwater chemistry through Principal Component Analysis (PCA) shows the significance of four factors controlling 78.37% of the total variance, including four-component (PC1 explained 27.89%, PC2 explained 24.98%, PC3 explained 14.64%, PC4 explained 10.85%). However, the individual contribution of Factor 1(PC1) explains 27.89% of the total variance (78.37%) and displays a strong optimistic loading for Ca and Cl. Further, high loading of Ca and NO and moderate loading of SO signify the contribution of burning fossil fuel and soil dust. Anthropogenic and natural pollutants influence the composition of rainwater in the pristine Himalayas due to local and long-distance transportation. The study area receives precipitation from the West and North-West, transporting dust and fossil fuel emissions from the Thar Desert and Northwestern countries.
本研究旨在分析位于印度喜马拉雅山西部巴斯帕盆地（32.19°N，78.20°E）海拔 4221 米高处的绍恩加朗集水区雨水的化学行为。研究期间，在五个不同地点采集了 16 个绍恩加朗集水区的雨水样本。雨水的体积加权平均 pH 值范围在 4.59 到 6.73 之间，平均值为 5.47 ± 0.69，表明降雨呈碱性。雨水中的总离子强度范围在 113.4 到 263.3 µeq/l 之间，平均值为 169.1 ± 40.4 µeq/l。主要的优势阳离子是 Ca（43.10%）和 Na（31.97%），阴离子是 Cl（37.68%）、SO（28.71%）和 NO（23.85%）。计算了所有离子之间的离子比值。（NO + Cl）与 SO 的比值为 2.3，表明雨水呈酸性，因为存在 HNO、HSO 和 HCl。通过主成分分析（PCA）对雨水化学进行的多元统计评估表明，有四个因素控制了总方差的 78.37%，包括四个分量（PC1 解释了 27.89%，PC2 解释了 24.98%，PC3 解释了 14.64%，PC4 解释了 10.85%）。然而，因子 1（PC1）的个体贡献解释了总方差的 27.89%（78.37%），并显示出 Ca 和 Cl 的强烈正负荷。此外，Ca 和 NO 的高负荷以及 SO 的中负荷表明燃烧化石燃料和土壤尘埃的贡献。由于当地和长距离运输，人为和自然污染物影响了原始喜马拉雅山雨水的组成。研究区域接收来自西部和西北部的降水，从塔尔沙漠和西北国家运输灰尘和化石燃料排放物。
