Nature Connection- ‘Mangroves’, sentinels of the ecosystem | Current Affairs & Hindu Analysis: Daily, Weekly & Monthly - UPSC PDF Download

Introduction

• Mangroves stand as one of Earth's most invaluable ecosystems. These habitats thrive along coastal regions and play a pivotal role in safeguarding coastlines, preserving water quality, and offering sanctuary to various marine species. The significance of mangroves lies in their remarkable ability to shield coastal areas from soil erosion and prevent the intrusion of seawater, making them a truly remarkable natural phenomenon.
• Mangroves constitute the distinctive plant formations along tropical and subtropical sheltered coastlines. They possess an extraordinary capacity to endure saltwater, strong winds, fluctuating tides, and high temperatures (FAO-1952), featuring species like Rhizophora, Avicennia, Bruguiera, among others.

Ecological Contributions of Mangroves:

• Flood Regulation
• Groundwater Replenishment
• Stability of Shorelines and Protection Against Storms
• Retention and Export of Sediments and Nutrients
• Purification of Water
• Biodiversity Hotspots
• Cultural Significance
• Facilitation of Recreation and Tourism
• Mitigation and Adaptation to Climate Change

Threats to Mangrove Coverage

Human-Induced Activities

• Unregulated tourism activities introduce waste, sewage, noise, fumes, artificial lights, and disruptions that harm mangroves and their diverse ecosystems.
• The ongoing coastal development results in increased pollutants and the conversion of mangrove areas into other land uses.
• The urbanization, industrialization, and discharge of domestic sewage, industrial waste, and pesticides severely threaten mangrove habitats.
• The rapid growth of shrimp aquaculture across India's flat coastal terrains has significantly contributed to the conversion of mangrove areas. For instance, about 14 percent of aquaculture farms in the Godavari delta region have been built on mangrove lands (FAO).
• Approximately 40 percent of mangrove forests along the West Coast of India have been transformed into agricultural fields and residential settlements over the past three decades.

Impact of Climate Change

• Increasing sea levels lead to the submergence of mangroves and reduce freshwater nutrient influx, affecting these ecosystems adapted to specific tidal patterns.
• Erosion of coastlines causes the decline of mangrove coverage, disturbing their natural zonation patterns.
• Catastrophic weather events like cyclones and storms result in defoliation within mangrove areas, leading to their mortality.
• Alterations in sea temperatures disrupt the natural succession of mangroves. For example, Avicennia and Sonneratia (pioneer species) transitioning to Rhizophora and Bruguiera face disruption due to these shifts.

Role and Importance of Mangroves

• Flood Moderation and Erosion Prevention: Mangroves play a crucial role in regulating monsoonal tidal floods and mitigating coastal inundation while preventing soil erosion.
• Resource Supply and Biodiversity Support: They offer firewood, medicinal plants, and sustain diverse flora, avifauna, and wildlife. Mangroves also support seashore and estuarine fisheries.
• Protection from Natural Disasters: These ecosystems safeguard inland agricultural lands, livestock, and coastal areas from the impacts of hurricanes and tsunamis.
• Nutrient Recycling and Environmental Stabilization: Mangroves facilitate natural nutrient recycling and stabilize climates by moderating temperature, humidity, wind, and wave actions. They serve as natural carbon sinks.

Scientific Management of Mangroves

• Mapping and Assessment: Nationwide mapping using remote sensing methods and land surveys helps evaluate ecosystem degradation rates. Quantitative surveys, including climatic variations and growth rates, are essential.
• Conservation Measures: Including threatened mangrove species in the IUCN Red List, identifying reserve forest sites, afforestation in degraded areas, and disease/pest control are crucial.
• Community Involvement and Research: Engaging local communities in joint mangrove management, conducting research on mangrove ecology, microbiology, and biodiversity, and exploring management techniques are essential steps.
• Conservation Initiatives: Projects like "Mangroves for Future" coordinated by the IUCN across South Asia, Southeast Asia, and the Western Indian Ocean aim to protect these ecosystems.

Conclusion

An observed increase of 54 square kilometers in mangrove cover is a positive sign, requiring further efforts to stabilize low-lying coastal areas. Conserving mangroves, acting as natural purifiers of water pollutants, becomes imperative for environmental health.