Mangroves are a crossroad where oceans, freshwater, and land realms meet. They are among the most productive and complex ecosystems on the planet, growing under environmental conditions that would just kill ordinary plants very quickly. In general, mangroves have specialised root structures (breathing roots or pneumatophores) as a result from their physical adaptation to oxygen-poor or anaerobic sediments/soils. Mangrove forests are rich in biodiversity providing a habitat for wide varieties of animal and plant species. They are dynamic areas, rich in food. Live and decaying mangrove leaves and roots provide nutrients that nourish plankton, algae, fish and shellfish. Many of the fish caught commercially in tropical regions reproduce and spend time in the mangroves as juveniles or adults. Mangroves also help other species survive, forming dense forests that shelter monkeys, kangaroos, and tigers as well as shellfish and brightly colored corals.
Roles and benefits of mangrove forests:
- To protect coastal areas from coastal erosion and abrasionThe findings suggest that the trees shield the coastline by reducing the height and energy of ocean waves and offer hard evidence that deforestation could result in increased coastal damage from storms. The prevention of coastal erosion and sea water intrusion provides security to human settlement and sustainability of freshwater resources.
- The mangrove depends on its complex root system for stability, oxygen, and salt filtration. In 2007 U.S. Geological Survey scientists analyzing mangrove roots and soil up to 8,000 years old found that during periods of rising sea level, the roots grow faster and bolster the soil, which helps hoist the tree upward.
- To have educational and recreational potentialMangrove can be used as Ecotoursim. Such as at Bedul (Mangrove Bedul Ecotourism), Banyuwangi - East Java. Mangrove Bedul Ecotourism offers three different tours to explore its mangrove and wildlife.
- To mitigate climate change through CO2 sequestration. Mangroves are expert carbon scrubbers. A global inventory by McGill University environmental scientist Gail Chmura found that mangroves pack away carbon faster than terrestrial forests. Every year they hoard some 42 million tons, roughly equivalent to the annual carbon emissions of 25 million cars.
- Mangroves will reduce the impacts from natural disasters such as storms and tidal waves so that business activities and the surrounding human settlements can be salvaged.
Impacts and causes of mangrove degradation/loss
Degraded and loss of mangroves has caused coastal abrasion, sea water intrusion, flood, loss of settlements due to storm, loss of natural fishing areas, and opportunities to mitigate greenhouse gas emissions.
The above conditions are generally caused by:
- Over-harvesting of wood from mangrove forests.
- Conversion to aquaculture.
- Unsustainable urban and agricultural development.
- Neglected deforested mangrove areas.
Benefits from sustainable aquaculture practice:
- The construction of embankment ponds will become stronger because it will be supported by mangroves roots.
- Passer-bys can walk comfortably along the embankments as they will be protected from the sun by the canopy of mangrove forests.
- Mangrove leaves can be used as cattle feedstock (especially for goats) and its fruits can be made into jam, crackers, etc. for human consumption.
- Increased biodiversity, particularly fish and crab species will increase the income of local fishermen.
- Water quality of aquaculture will become better because mangrove roots can filter solid waste while the micro-organism found on the floor of mangrove forests can decompose organic materials from inside and outside aquaculture activities.
- The formation of coastal greenbelt not only will protect the coastal settlement from sea level rising, but also support climate change mitigation and adaptation programme because mangroves sequester CO2 from the atmosphere.