Photo: Nan Liu Estuar, Guangxi, China; by Sun Ting; 31.08.2010

Changing Coastal Lands - Mangroves vs. Aquaculture

Mangrove forests occupy the coasts of many tropical and subtropical areas. There they serve a variety of functions important for both terrestrial and marine coastal systems. Among these is the reduction of human created water pollution. Unfortunately, mangroves have widely been perceived as useless and even dangerous swamps. Their position at the border between land and sea is also attractive for land-based aquaculture in need of brackish water supply. So for several decades these diverse and productive habitats have been destroyed to make space for aquaculture ponds. New areas are converted because of the growing industry and because ponds can only be used for a relatively short span of time. The ecological consequences of this change are more far-reaching than the destruction of the forests. However, generalizations are difficult to make due to the dynamic nature of the coastal zone and the multitude of influencing factors. Despite the uncertainties, authorities in many countries have realized the importance of protecting and understanding mangrove ecosystems. In China, today the largest producer of aquaculture products, mangroves are placed under general national protection.

In my GLOMAR-supported studies in the south of China, I aim to understand thebiogeochemical dynamics of an estuarine system that is strongly impacted byaquaculture. One focus lies on the role of the remaining mangrove forestsinhabiting the river mouth. .

David Kaiser, GLOMAR PhD-student