Mangroves are salt-tolerant vegetation that grows in intertidal regions of rivers and estuaries. They are referred to as ‘tidal forests’ and belong to the category of ‘tropical wetland rainforest ecosystem’.
Causes of Depletion of mangroves
Sea level rise and coastal erosion
Due to global warming, the sea levels are continuously rising. The rising sea levels have flooded large areas of mangrove forests. This has resulted in their depletion. This has been supplemented by continuous erosion by sea towards the land.
Reduction in river water levels
The mangroves are more prevalent in areas where the rivers meet the sea. The system requires a fine balance between salt and sweet water to survive. Reduction of river water due to dams has caused destruction of mangroves.
Invasion by alien species
Introduction of non-native and alien species of plants and animals are causing threat to the endemic species of the region. This has led to imbalance in ecological structure, resulting in their depletion.
Clearing
Large tracts of mangrove forests have been cleared to make room for agricultural land, human settlements, industrial areas, shrimp aquaculture etc. As a result, mangroves get depleted to the tune of 2-8 percent annually.
Environmental monitoring in the existing mangrove areas should be taken up systematically and periodically. Various threats to the mangrove resources and their root causes should be identified, and earnest measures should be taken to eliminate those causes.
The participation of the local community should be made compulsory for conservation and management. Floristic survey of mangroves along the coast is to be taken up to prepare biodiversity atlas for mangroves.
Potential areas are to be identified for implementing the management action plan for mangroves, especially in cyclone prone areas. Socioeconomic studies on the mangrove-dependent people need to be taken up to involve them in management of mangrove biodiversity.
Coastal industries and private owners need to be persuaded to actively participate in protecting and developing mangrove biodiversity. The forest department officials should be trained on taxonomy, biology and ecology of mangrove species.