Environment and Sustainable Development, Central University of Gujarat, Gandhinagar, 382030, Gujarat, India.
Environ Res. 2021 Apr;195:110803. doi: 10.1016/j.envres.2021.110803. Epub 2021 Feb 2.
The present study is an attempt to assess the spatial and seasonal variation of nutrients and heavy metals in mangroves water in the Gulf of Kachchh, India. The surface water samples were collected during pre- and post-monsoon to evaluate the hydrochemical processes occurring in the region. Seasonal changes and anthropogenic inputs have influenced the nutrients and metal concentrations. The results suggest high salinity (Pre-monsoon ±45.59 PSU; post-monsoon ±45.36 PSU) and chloride (Pre-monsoon ±30251 mg/L; post-monsoon ±29536 mg/L) concentration in both the seasons. Average values of Sulfate (SO), Nitrate (NO), Dissolved silica (DSi), and Phosphate (PO) was 2503.69 mg/L, 10.47 mg/L, 35.41 mg/L and 0.85 mg/L in pre-monsoon, and 3474.50 mg/L, 13.66 mg/L, 31.54 mg/L and 0.64 mg/L in post-monsoon, respectively. Nutrient ratios indicate phosphorus limitation in both the seasons. Cluster and Principal Component analysis signifies that sampling locations in cluster 3 and factor 1 majorly impacted due to seawater mixing, high evaporation and discharge of brine from saltpans, while cluster 2, 3 and factor 2 indicates the anthropogenic source. Metal concentration was higher during pre-monsoon and among the metals, Fe, Sr, Zn and Mn were observed in high concentration. The hydrochemical characteristics of water found to be dependent on the peculiarity of sampling locations such as high tidal amplitude, less freshwater input, arid climate, extensive saltpans, tidal flushing, instinctive reducing environment and anthropogenic discharge. Gulf of Kachchh is an industrial hub of the country, where anthropogenic activities (such as fertilizer, cement, and chemicals industries, oil and petroleum refineries, metal processing units, thermal power plants and ports activities) are the prime sources of contamination, which are affecting water quality. The relatively high concentration of nutrients and metals suggests that water is in very dreadful condition, which will ultimately affect flora and fauna of this ecosystem. This study provides baseline information on mangrove water quality and impacts of ongoing anthropogenic activities on the Gulf of Kachchh.
本研究旨在评估印度卡奇湾红树林水中营养物质和重金属的空间和季节性变化。采集了前、后季风期间的地表水样本，以评估该地区发生的水化学过程。季节性变化和人为输入影响了营养物质和金属浓度。结果表明，两个季节的盐度（前季风±45.59 PSU；后季风±45.36 PSU）和氯化物（前季风±30251 mg/L；后季风±29536 mg/L）浓度均较高。前季风时硫酸盐（SO）、硝酸盐（NO）、溶解硅（DSi）和磷酸盐（PO）的平均值分别为 2503.69 mg/L、10.47 mg/L、35.41 mg/L 和 0.85 mg/L，后季风时分别为 3474.50 mg/L、13.66 mg/L、31.54 mg/L 和 0.64 mg/L。营养物质比值表明两个季节均存在磷限制。聚类和主成分分析表明，聚类 3 和因子 1 中的采样点主要受到海水混合、高蒸发和盐田卤水排放的影响，而聚类 2、3 和因子 2 则表明存在人为来源。前季风期间金属浓度较高，其中 Fe、Sr、Zn 和 Mn 浓度较高。水样的水化学特征取决于采样点的特殊性，如高潮幅、淡水输入较少、干旱气候、广泛的盐田、潮汐冲洗、本能的还原环境和人为排放。卡奇湾是该国的工业中心，人为活动（如化肥、水泥和化工、石油和炼油厂、金属加工单位、火力发电厂和港口活动）是污染的主要来源，影响着水质。相对较高的营养物质和金属浓度表明，水的状况非常糟糕，这将最终影响该生态系统的动植物。本研究提供了红树林水质的基准信息以及人为活动对卡奇湾的影响。
