ABSTRACT
The Caspian Sea, the world's largest enclosed water body, experiences significant transformations in its physico-chemical properties and a decline in bioresources due to extensive anthropogenic activities. These activities include the discharge of diverse pollutants and bio-physical alterations such as over-fishing, hunting, and physical alterations to rivers. While acute manifestations such as a fall in the Caspian water levels and wetland desiccation are more overt, the pervasive impact of human activities contributes to a likely irreversible decline in environmental quality that we aim to spotlight in this discussion in order to facilitate its restoration.
ABSTRACT
Mand River is one of four permanent rivers flowing into the Persian Gulf. Intense industrial activities have significantly impacted its watershed and estuary. In order to evaluate metal contamination and their provenance nine sediment samples were taken from the Mand Delta. Enrichment factors were employed to detect anthropogenic contributions to levels of metal pollution. We also calculated weathering indices in order to identify the source of the metals, related to geological units. Pollution levels were assessed using the modified degree of contamination. Geological units, oil combustion, aerosols and industrial activities are the main factors controlling the abundance of Cr, As, Ni and Pb. Wave action, coastal currents, grain-size parameters, mineralogy, bio-accommodation and organic matter are the factors affecting the distribution and concentration of metals in the study area. More studies are needed to evaluate the impact of metal pollution on the fisheries industry and public health.
