A detailed study on potential sources, variation, and environmental effects of the rainwater ions was carried out at Lothian Island, Sundarban mangrove forest, India, during the southwest monsoon (June–September) in 2019. On an event basis, the maximum rainwater precipitation was observed 17.65 mm Day ⁻¹ and a minimum of 1.02 mm Day ⁻¹. The maximum amount of total precipitation was recorded in the month of July (237 mm). The volume weighted mean (VWM) concentration shows that the total ionic composition was 93.7 μeq L⁻¹, whereas the percentage contribution of the total ionic concentration is found to be 45.97% to anions and 54.02% to the cations. Temporal variation was observed between early (June- July) and late monsoon (August—September), which shows a high concentration of major ions in early monsoon and low concentration in late monsoon due to the washout of atmospheric particles with the frequent and increasing precipitation. The pH values of the 78% samples show neutral pH and neutralization factors (NF) followed a sequence of NF_Ca ˃NF_Mg ˃ NF_NH4 with factors of 0.77, 0.34, and 0.14 indicating Ca²⁺ was the most potential species to balance the acidic ions (NO₃⁻, SO₄²⁻) over the study area. Source apportionment study indicates the significant influence of marine actions (long-range transport by monsoonal wind from marine origin, Sea spray, salty soil profile of mangrove) as the major source of ions over Sundarban. The rate of nutrient wet deposition in the form of rainwater was estimated and average monsoonal nitrogen flux was observed 0.87 kg ha⁻¹where NO₃ contributes the most (0.60 kg ha⁻¹). N and P deposition flux also showed a simultaneous pattern with the seasonal nutrient concentration of surrounding river water, which may be an indication of a possible contribution of atmospheric wet deposition in the spike of monsoonal nutrient concentration in river water.

在 2019 年西南季风期间（6 月至 9 月），在印度孙德尔班红树林洛锡安岛对雨水离子的潜在来源、变化和环境影响进行了详细研究。根据事件，最大雨水降水量在第^-1天观察到 17.65 毫米，在第^-1天观察到最少 1.02 毫米。7 月份（237 毫米）记录了最大总降水量。体积加权平均 (VWM) 浓度显示总离子组成为 93.7 μeq L ^-1，而总离子浓度的百分比贡献被发现为阴离子的 45.97% 和阳离子的 54.02%。观测到季风早期（6-7月）和季风晚期（8-9月）的时间变化，主要离子浓度在季风早期高，在季风晚期由于大气颗粒物的冲刷，降水频繁且增加. 78% 样品的 pH 值显示中性 pH 值和中和因子 (NF) 遵循 NF Ca˃NF Mg˃ NF NH4 的序列，因子为_{0.77、0.34和}0.14 _，表明Ca ²⁺是最有可能平衡酸性离子 (NO ₃ ^- , SO ₄ ^2-) 在研究区域。源解析研究表明，海洋活动（来自海洋的季风远距离运输、海浪、红树林的盐渍土壤剖面）作为孙德尔班上空的主要离子来源具有显着影响。估计了雨水形式的养分湿沉降速率，观测到平均季风氮通量为 0.87 kg ha ^-1其中 NO ₃贡献最大（0.60 kg ha ^-1）。N 和 P 沉降通量也显示出与周围河水季节性养分浓度同步的模式，这可能表明大气湿沉降可能对河水中季风养分浓度的峰值有贡献。