Mangroves in India
- Mangroves are salt-tolerant plants, also called halophytes that are adapted to harsh coastal conditions of tropical and subtropical intertidal regions receiving rainfall between 1,000 to 3,000 mm and temperature ranging between 26-35°C.
- Since mangroves are located between the land and sea, they represent the best example of ecotone.
- About one third of the world’s mangroves are found in Asia (39%), followed by Africa (21%) and North and Central America (15%).
Ecological adaptations
Pneumatophores, commonly found in mangrove species that grow in saline mud flats, are lateral roots that grow upward out of the mud and water to function as the site of oxygen intake for the submerged primary root system.
Buttress roots also known as plank roots/ stilt roots are large, wide roots on all sides of a shallowly rooted tree. Typically, they are found in nutrient-poor tropical forest soils that may not be very deep. They prevent the tree from falling over (hence the name buttress) while also gathering more nutrients.
- Adaptations to low oxygen: By propping themselves above the water level with stilt roots and can then absorb air through pores in their bark (lenticels).
- Nutrient uptake: Pneumatophores (aerial roots) allow mangroves to absorb gases directly from the atmosphere.
- Limiting salt intake: Mangroves exclude salt by having significantly impermeable roots.
- Limiting water loss: They can restrict the opening of their stomata (pores on the leaf surfaces, which exchange carbon dioxide gas and water vapor during photosynthesis).
- Increasing survival of offspring: Mangrove seeds are buoyant and are therefore suited to water dispersal.
Importance of Mangroves
- Act as a Buffer Zone between the land and sea. Act as nature’s shield against cyclones and ecological disasters and as a protector of shorelines.
- Breeding and nursery grounds for a variety of marine animals. Harbours a variety of life forms like invertebrates, fish, amphibians, reptiles, birds & even mammals like tigers.
- Good source of timber, fuel and fodder.
- Main source of income generation for shoreline communities like fisher folk.
- Purify the water by absorbing impurities and harmful heavy metals and help us to breathe clean air by absorbing pollutants in the air.
- Potential source for recreation and tourism.
Distribution of mangroves in Indian subcontinent
| Sundarbans, West Bengal | Largest single block of tidal halophytic mangrove in the world. Famous for Royal Bengal Tiger & saltwater crocodiles. |
| Bhitarkanika, Odisha | 2nd largest mangrove forest in India. High concentration of typical mangrove species & high genetic diversity. |
| Godavari-Krishna delta, Andhra Pradesh | Mangrove swamps occur in profusion in the intertidal mudflats on both side of the creeks |
| Maharashtra, Goa & Karnataka | Mostly scrubby & degraded mangroves occur along the intertidal region of estuaries and creeks |
| Kerala | Very sparse and thin. |
| Gulf of Kutch & Kori creek, Gujarat | Dwarf mangroves. Gujarat has India’s second largest area under Mangroves after Sundarbans. |
| Andaman & Nicobar Islands | Small tidal estuaries, neritic inlets and lagoons support a dense & diverse undisturbed mangrove flora. |
| According to the State of Forest Report 2021 Mangroves cover 0.15% of the country’s total geographical area.There has been a net increase of 17 sq km of mangrove cover in the country as compared to 2019 assessment. Odisha has shown most gain in 8 sq km and Maharashtra 4 sq km.Order of States by Mangrove Cover: West Bengal (42.5%), Gujarat (23.6%). The ‘State of World Mangroves 2022’ points out that mangroves are estimated to hold up to four times the amount of carbon as some other ecosystems.The loss of even 1% of remaining mangroves could lead to the loss of 0.23 gigatons of CO2 equivalent. | |
Budget 2023-24 FOR GREEN DEVELOPMENT MISHTI Program: (Mangrove Initiative for Shoreline Habitats & Tangible Incomes): mangrove plantation will be taken up along the country’s coastline and salt pan lands.
Initiative to protect Mangrove
- MANGROVES FOR FUTURE (MFF): A collaboration between multiple partners, including governments, NGO, research institutes etc. It is co-chaired by the IUCN and UNDP. The goal is to promote an integrated ocean-wide approach to coastal management and to building the resilience of ecosystem-dependent coastal communities. MFF is inclusive of all types of coastal ecosystem, such as coral reefs, estuaries, lagoons, sandy beaches, seagrass and wetlands. India is a member country.
