Coastal wetlands are found in the transition area (ecotone) between the land and the open sea. Coastal wetlands are not much influenced by rivers. Seagrass meadows, intertidal flats, tidal salt marshes, mangrove forests, and tidal freshwater wetlands are examples of coastal wetlands. They are found in all continents and latitudes except the poles. Coastal wetlands are crucial for adapting to climate change. They are effective carbon sequesters, and the wetland's vegetation, stable sediment, and soil conditions reduce wave velocity, protecting coastlines from storms and flooding. This article will explain to you about the Coastal Wetland Ecosystem which will be helpful in Environment preparation for the UPSC Civil service exam.

What exactly are Coastal Wetlands?

• The region of land that is permanently or periodically inundated with fresh, brackish, or saline water is known as coastal wetlands.
• Coastal wetlands are unique habitats that are influenced by changing water levels and provide habitat for a diverse range of organisms, including many endangered species.
• In certain circumstances, such as in southern Louisiana along the north-central Gulf of Mexico, coastal wetlands can cover vast swaths of land.
• These vital elements serve as a water purifier, breeding and feeding grounds for fish, and habitat for a variety of animal species.
• By providing friction against an incoming storm surge, they help buffer inland populations from the huge storm surges that tropical cyclones can create, reducing the volume and breadth of inland flooding during tropical storms.
• The more intact wetlands there are, the less probable it is that further inland places will be hit by the full brunt of a tropical cyclone.

Types of Coastal Wetlands

Coastal wetlands are classified into two main categories based on their nature of formation namely: Natural Coastal Wetland and Manmade Coastal Wetland.

Natural Coastal Wetland

• Natural coastal wetlands are wetlands that are formed naturally.
• Salt marshes, bottomland hardwood swamps, fresh marshes, mangrove swamps, and shrubby depressions are all forms of wetlands found in Natural coastal watersheds.
• Examples: Chilika lake Orissa and Ashtamudi wetland Kerala, Bhitarkanika Orissa, Sunderbans West Bengal, Gulf of Khambhat Gujarat

Lagoon

• Lagoons are shallow water bodies that are separated from large water bodies.
• They are separated from the ocean by coral reefs, barriers and sandbars.
• Lagoons also form a part of estuaries.
• They are classified in freshwater lagoons or saltwater lagoons.
• Example: Chilika lake Orissa and Ashtamudi wetland Kerala.

Creek

• A creek is defined as a narrow piece of water on the land.
• This usually acts as an inlet of seawater into the Land.
• They are smaller channels of water when compared to rivers which are voluminous.
• The creek forms an important part of coastal wetlands as they support high flora and fauna and are rich in biodiversity.
• Example: Kori creek Gujarat.

Sand/ Beaches

• The sand and beaches are formed along the coast due to the actions of waves.
• They are coastal landforms that contain loose particles.
• Sands and beaches act as a transition between the continental shelf and the slope.
• Beeches provide ecosystem services like sediment storage and transport.
• Sand beaches are rich in biodiversity and they mainly act as hatching grounds for coastal ecosystems.
• Coast of Tamilnadu, Orissa, and Gujarat are major examples.

Mangroove

• Mangroves are permanently and semi-permanently submerged in water and are mainly found in tropical and subtropical areas.
• They support extreme weather conditions and high biodiversity.
• Mangrove forests are important nesting grounds for shorebirds and migratory birds.
• Mangrove helps in coastal protection by reducing the impacts of strong waves from the open seas.
• Example: Bhitarkanika Orissa, Sunderbans West Bengal, Gulf of Khambhat Gujarat.

Salt Marsh

• Salt marshes have nonwoody vegetation (herbaceous) which is formed in wet soil conditions.
• They are characterized as tidal marshes and non-tidal marshes.
• They are seasonally filled with water.
• Salt marshes are found along the coastline of Tamilnadu, Orissa, Gujarat , Maharashtra, etc.

Coral Reef

• Coral reefs are the most vulnerable ecosystem, consisting of underground reef-building corals.
• Coral reefs facilitate the highest biodiversity of any ecosystem in the world.
• They provide ecosystem services like flood protection, sustaining fishing grounds, and social and health benefits.
• Global warming poses a major threat to the coral reef.
• Examples: Gulf of Mannar, North reef island of Andaman and Nicobar islands.

Manmade Coastal Wetlands

• Man-made coastal wetlands are wetlands that are formed due to human activities.
• Man-made wetlands are used in various activities to support the livelihood of the community.
• Examples include aquaculture ponds like shrimp ponds. They are also called fish ponds which support marine and freshwater diversity of species.
• Examples: Sambhar lake Rajasthan, Gulf of Kachchh Gujarat.

Aquaculture Ponds

• They are manmade ponds that serve the purpose of nurturing aquatic species.
• They are also called fish ponds which support marine and freshwater diversity of species.
• They are artificial and provide commercial services.
• Examples: Kolleru Lake Andhra Pradesh.

Salt Pan

• A salt pan is a surface that is covered with salt and other minerals.
• They are commonly found in deserts.
• The minerals present in the salt pan act as a reflector in sun rays.
• Salt pan holds rich species like birds and insects which survive there.
• The significance of the salt pan here is that it has a high water-holding capacity which assists in flood control.
• Examples: Sambhar lake Rajasthan, Gulf of Kachchh Gujarat.

Coastal Wetlands in India

• The coastal wetlands of India include those on the east coast, the west coast of mainland India, and the Andaman and Nicobar islands, and have a peninsular structure along with eight states in the south.
• Coral reefs, rocky shores, and coastal wetlands such as mangroves, estuaries, lagoons, creeks, tidal/mud flats, and salt marshes may be found along India's coast, covering a total area of 3,880,569 hectares.
• Natural coastal wetlands account for 24.27 percent of all wetlands in India.
• In India, mangroves are the most common type of coastal wetlands, covering 4,87,100 hectares.

Importance of Coastal Wetlands

• Flood protection: Coastal wetlands protect upland areas from floods caused by sea-level rise and storms, including important residential and commercial property.
• Erosion Control: Coastal wetlands can help to reduce coastline erosion by absorbing the energy produced by ocean currents, which would otherwise erode a shoreline and its related development.
• Wildlife Food & Habitat: Coastal wetlands provide temporary habitat for waterfowl and shorebirds on two of North America's migratory bird flyways, which travel across the Pacific and Atlantic coasts. Many vulnerable and endangered species, such as the Whooping Crane, Louisiana Black Bear, and Florida Panther, rely on coastal wetlands for their survival.
• Coastal Commercial Fisheries: Coastal wetlands are home to more than half of the commercial fish and shellfish species in the Southeast United States.
• Water Quality: Coastal Wetlands improve the water quality of the water. It acts as a filtering agent by protecting and filtering the chemicals in the water.
• Recreational Property: Canoeing, kayaking, wildlife observation and photography, recreational fishing, and hunting are some of the recreational activities available in coastal wetlands.
• Carbon Sequestration: Due to their rapid growth rates and slow breakdown rates, many coastal wetland ecosystems (such as salt marshes and mangroves) may sequester and store huge amounts of carbon.

Threats to Coastal Wetlands

Human activities

• Human activities play a vital role in the decline of natural coastal wetlands.
• Urban and rural development, agriculture, and silviculture are all human activities that may result in the loss of coastal wetlands.
• These land-use changes can also have an indirect impact on surrounding wetlands by affecting hydrology in the watershed, which can result in increased runoff or water withdrawals.

Natural Processes

• Natural processes coupled with accelerated climate change affect wetlands in most parts of the world.
• High-energy events, such as erosion and inundation from sea level rise and storms, naturally affect coastal wetlands, particularly estuarine and marine wetlands.
• Climate change and shoreline armoring may amplify the effects of these processes.
• Estuarine wetlands protect the shoreline from erosion and flooding, but as sea levels rise and development prevents wetlands from migrating inland, more wetlands will be converted to open water.

Conclusion

Coastal wetlands are quickly disappearing while being one of the most widely exploited and threatened natural systems on the planet. The most significant difficulty is a lack of information about how to link changes in ecosystem structure and function to the production of valuable commodities and services, particularly nonmarketable goods and services. These values can then be used to lead adjustments in coastal policies and management that are required to regulate the human drivers of ecosystem change.Keywords: Coastal wetlands, transition area, ecotone, salt pan, Coral Reef, Salt Marsh, Mangrove, Seagrass meadows, intertidal flats, tidal salt marshes, mangrove forests, tidal freshwater wetlands,

FAQs

MCQs

1. Which of the following is a type of coastal wetland?

A) Desert
B) Forest
C) Mangrove
D) Grassland

2. Which of the following is a major threat to coastal wetlands?

A) Excessive rainfall
B) Land reclamation
C) Overhunting
D) Desertification

3. Which of the following ecosystems helps in carbon sequestration?

A) Coastal wetlands
B) Mountain ecosystems
C) Desert ecosystems
D) Urban forests

4. Which of the following is a direct benefit of coastal wetlands?

A) Agricultural expansion
B) Flood protection
C) Increased industrial activity
D) Deforestation

5. Which of the following is NOT a feature of coastal wetlands?

A) Salt-tolerant vegetation
B) High biodiversity
C) Inundated with saltwater
D) Located in the interior of continents

GS Mains Questions and Model Answers

Q1: Discuss the role of coastal wetlands in mitigating the impacts of climate change.

Answer: Coastal wetlands play a crucial role in mitigating the impacts of climate change by acting as carbon sinks. Mangroves, salt marshes, and seagrass beds sequester large amounts of carbon in the form of organic material in sediments, helping to reduce the concentration of greenhouse gases in the atmosphere. These ecosystems also provide protection from extreme weather events, such as storms and floods, by acting as natural barriers. Coastal wetlands absorb excess water, reduce erosion, and shield coastal communities from the effects of rising sea levels, making them integral to climate change adaptation and mitigation strategies.

Q2: How can the destruction of coastal wetlands affect human populations?

Answer: The destruction of coastal wetlands can have severe consequences for human populations, especially those living in coastal areas. Wetlands provide a natural buffer against storm surges, flooding, and erosion, helping to protect infrastructure, agriculture, and human settlements. The loss of these ecosystems increases vulnerability to extreme weather events, leading to greater damage during storms and floods. Additionally, coastal wetlands support fisheries by acting as nurseries for marine species, so their destruction can negatively impact local livelihoods. The degradation of wetlands also leads to the loss of biodiversity and the ecosystem services they provide, exacerbating environmental and socio-economic challenges.

Q3: What conservation measures can be adopted to protect coastal wetlands from further degradation?

Answer: Conservation measures for coastal wetlands include the enforcement of laws to prevent land reclamation, pollution, and unregulated development in wetland areas. Restoration projects that involve replanting mangroves and seagrasses can help rehabilitate degraded wetlands. Coastal zoning regulations should be established to limit human activities that harm wetlands, and protected areas should be created to preserve these ecosystems. Furthermore, integrating wetland protection into broader climate change adaptation strategies, such as reducing emissions and managing water resources, will ensure long-term sustainability. Public awareness campaigns and community involvement in conservation efforts are also essential to safeguard the future of coastal wetlands.

Previous Year Questions on Coastal Wetlands

1. UPSC CSE Prelims 2020:

Question: Which of the following is an important function of coastal wetlands?

A) Mitigating air pollution
B) Sequestering carbon
C) Controlling desertification
D) Promoting biodiversity in forests

Answer: (B)

Explanation: Coastal wetlands act as carbon sinks, helping to sequester carbon and mitigate climate change by storing carbon in the form of organic material in sediments.

2. UPSC CSE Mains 2019 (GS Paper 3):

Question: Examine the role of coastal wetlands in maintaining biodiversity and their significance in the context of climate change.

Answer: Coastal wetlands are rich in biodiversity, providing habitats for numerous plant and animal species. They are especially important for migratory birds, juvenile fish, and other marine organisms. By acting as carbon sinks, coastal wetlands help mitigate climate change. They absorb large amounts of carbon dioxide and store it in the form of organic matter. Furthermore, these ecosystems protect coastal areas from erosion, storm surges, and rising sea levels. Preserving coastal wetlands is essential for maintaining biodiversity and enhancing resilience against climate change.