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Sand mining is a global activity that is receiving increasing media attention due to perceived negative environmental and social impacts. As calls grow for stronger regulation of mining, there is a need to understand the scientific evidence to support effective management. Mpenjati river is one of the longest rivers in the lower south of KwaZulu Natal its flows in between mountains that is reach in variety of vegetation types and grasslands, sand mining has been spotted as the highest threat to the river and caused the water quality and quantity becomes harmful to plants, vertebrates and invertebrates fauna in the river. Several methods and material has been used to analyse, interpreted to reveal reliable results of the study of the river. The results of the research disclosed that there were many negative impacts which affects the river besides sand mining that changes water quality e.g. in July month had lot of wind that collects all sediments and deposited to the river, solar radiation and absence of riparian vegetation increased the temperature of the water which lead to high turbidity as well, quarry sediments also affected water quality of the river and extraction of sand at the banks of river system affected the quality of the river system .Rivers are dynamic and their physical and chemical characteristics can change over a scale of hours to years. Consequently, river and estuarine fish assemblages often exhibit large temporal variations in abundance and composition related to changes in a range of parameters such as river flow, river mouth phase, habitat availability, temperature, salinity and turbidity, all of which are likely to be highly affected by climate change. Many organisms become more stressed towards their range boundaries and the distributions of these species can be expected to shift as environmental conditions change. |
