Discuss the causes of depletion of mangroves and explain their importance in maintaining coastal ecology.

Mangroves or tidal forests are salt-tolerant vegetation that grows in intertidal regions. They have significant environmental and economic benefits but are under serious threat due to anthropogenic activities.

Causes of Depletion:

1. Clearing of forest for agriculture, infra projects and shrimp farming.
2. Overexploitation for fuelwood, softwood, leaves etc.
3. Increased freshwater flow from rivers disturbs the salinity and sediment balance.
4. Rise in SST (Sea surface temperature) leading to warming up of water bodies and increased instances and intensity of cyclones, floods, etc.

Role of mangroves in maintaining coastal ecology:

1. Highly diverse ecosystem housing a variety of flora and fauna, often exotic and threatened ones.
2. Natural breakwaters to cyclones, tsunami and storm surges protecting coastal ecosystems.
3. Water filtration and aquifer recharge.
4. Provision of tangible output like wood, leaves etc.
5. Recreation, tourism and livelihood for coastal communities.

Strict policy implementation, community level participation and global consensus should be key to restoring the critical mangrove ecosystems and preventing further damage, in accordance with SDG 13.