Question – How does an increase in greenhouse gas (GHG) emissions affect coastal and marine ecosystems? Throw light on the various measures that can be adopted for the conservation and restoration of such vulnerable ecosystems. – 8 November 2021
The increase in the level of greenhouse gas (GHG) in the earth’s atmosphere is mainly due to anthropogenic activities like combustion of fossil fuels, industrial emissions, deforestation, animal husbandry etc. It is responsible for changes in the Earth’s climate. Since global warming is now observed even at depths of 1000 m, important coastal ecosystems such as wetlands, estuaries and coral reefs are particularly vulnerable to global warming and climate change.
The emissions of GHGs such as CO2 and methane contribute to global warming, and affect coastal and marine ecosystems in the following ways:
- Physical and chemical properties of sea water: GHGs induces global warming, resulting in increased sea surface temperatures, ocean acidification and de-oxidation. This results in changes in ocean circulation and chemical composition, a rise in sea level, and an increase in storm intensity.
- Marine Life: Changes in the physical and chemical properties of ocean water have negative effects on the diversity and abundance of marine species. Acidification of the oceans reduces the ability of corals, phytoplankton and shelffish to form shell and skeletal structures.
- Human Settlements: Sea level rise causes coastal erosion, saltwater ingress, habitat fragmentation and loss of coastal human settlements.
- Security: The effects of global warming can threaten the physical, economic and food security of coastal communities of about 40% of the world’s population.
- Threat to island nations: Small island developing states, such as Tuvalu, Mauritius, Maldives, etc., are at risk of being submerged.
Important ecosystem services such as carbon storage, oxygen production, food and income generation are provided by coastal and marine ecosystems. Given the gravity of the problem, there is an urgent need for various measures for conservation and restoration to prevent future degradation of marine and coastal ecosystems.
- Establishment of Marine Protected Areas: At the IUCN World Congress of Conservation, IUCN members approved a proposal to conserve 30% of Earth’s oceans by 2030. This will help in the conservation of ecologically and biologically important marine habitats. Also, human activities can be regulated to prevent environmental degradation.
- Policies should be put in place to prevent the conversion or conversion of these ecosystems to other land uses. For example, India has notified Coastal Regulation Zone (CRZ) guidelines in this regard.
- International cooperation between countries is essential for implementing sustainable practices in all industries affecting the oceans and coasts (including the fishing and tourism industries). For example, ‘Mangroves for the Future’ is a multi-national partnership that promotes investment in coastal ecosystem conservation for sustainable development.
- Scientific research should be conducted to adopt suitable mitigation and adaptation strategies. The collaborative partnership of IUCN and the IPCC can make a significant contribution in this regard.
Sustainable management, conservation and restoration of coastal and marine ecosystems is critical to supporting the sustainable management of ecosystem services (on which people depend). A low-carbon development pathway is essential to preserve the health of these vulnerable ecosystems.