Aquatic Coastal Ecosystems of Monsoon Asia (ACEMON): Their Biogeochemical Response to Natural and Anthropogenic Perturbations

Monsoon Asia region is among some of the densely populated areas of the world. Its climate is characterized by seasonal weather patterns associated with the two monsoons which drive physical and biogeochemical processes in this physiographically diverse region with its rich natural and crop- agriculture related biodiversity. Their diverse aquatic ecosystems have been a source of resources that sustain the lives of millions of people with very large number of rivers and lakes ( both natural as well as manmade) acting as major food suppliers for the population Multiple stress from natural and anthropogenic changes including those within river drainage basins have altered their structure and dynamics reducing their ability to provide goods and services.

Glaciers in the Himalayas feed some of World’s largest rivers which contribute to the bulk of material flux from land to the sea. Deforestation and topsoil erosion have added to their naturally high sediment loads, causing turbidity and siltation on estuaries, lakes and coastal lagoons. On the other hand, hydrological alterations retain nutrients and sediments in artificial lakes and reservoirs behind dams. Activities related to the ongoing rapid regional development have increased the risk of pollution from domestic and industrial waste. All these have an impact of waterbodies located between high altitude plateaus and low-lying coastal plains in the region.

The impact is manifested in their changing environmental carrying capacity and perturb the biogeochemical processes that sustain these waterbodies. The scales and degrees of the perturbation vary, and are reflected in their biogeochemistry, and in the quality of the ecosystems they sustain. These anthropogenic perturbations are exacerbated by the projected climate change (e.g., changing monsoon strengths, sea level rise, inundation and flooding, salination and extreme events). The impact of climate change is accelerating the hydrological processes of the water bodies in such as way the UN sustainability goals are increasingly becoming unachievable.