11 Wetlands and Mangroves

Saleha Jamal

1. Wetlands

Structure

1.1 Introduction

1.2 Definition of Wetland

1.3 Importance and Significance of wetlands

1.4 Types of Wetlands

1.5 Ramsar Convention and Sites

1.6 Wetlands of India

1.7 Environmental Threat to Wetlands

1.8 Wetland Conservation and Management

1.9 Conclusion

1.1 Introduction

Wetlands are those areas where water is the main factor controlling environment and the associated plants and animal life. Wetlands are formed in those areas where the water table is at the surface of the land, near the surface of the land or where the land surface is covered by water. Wetlands are treated as transitional habitat between terrestrial (land) and aquatic (land) consisting of a wide variety of habitat types and this is the reason why these wetlands are considered to have a distinct ecosystem with specific ecological characteristics, function and values. All wetlands perform certain function and hence have some values. Wetlands may be natural and manmade, freshwater or brackish that provides numbers of ecological services. If the density of birds found in a particular ecosystem is high this indicates that the ecological health of that ecosystem is good. However, unsustainable use of wetland without reckoning of their assimilative capacity constitutes major threat to the conservation and management of these vital biodiversity rich areas. Thus, restricting the prospects for the future generation in utilize the benefits of the ecosystem services provided by these wetlands. February 2nd of every year is celebrated as wetland day.

    1.2 Definition of Wetlands

The most accepted definition of wetlands is “lands transitional between terrestrial and aquatic eco-systems where the water table is usually at or near the surface or the land is covered by shallow water”. Ramsar Convention defines wetland as: areas of marsh, fen, peat land or water, whether natural or artificial, permanent or temporary, with water that is static or flowing, fresh, brackish or salt, including areas of marine water the depth of which at low tide does not exceed six metres”. This include all inland waters such as lakes, reservoirs, tanks, backwaters, lagoon, creeks, estuaries and manmade wetland and the zone of direct influence on wetland that is to say the drainage area or catchment region of the wetlands as determined by the authority but does not include main river channels, paddy fields and coastal wetlands.

1.3 Importance and Significance of Wetlands

Wetlands plays very important role in the hydrological cycle. They provide various services like purification and regulation of flows, fisheries, habitat to plants, animals and birds and by that it provides opportunities for recreation and tourism. Since the wetlands regulate hydrological functions they act as a buffer against drought and floods. Besides playing a crucial role in the hydrological cycle, wetlands are the most productive ecosystems of the world and the potential source of carbon sequestration although they account only for about 4 per cent of the earth’s ice-free land surface. Wetlands absorbs and restore water in monsoon and by that they reduce the risk of floods, whereas in winter and summer wetlands gradually release water and hence ensure its availability to surrounding and downstream areas. Wetlands such as coral reefs, beaches, reservoirs, lakes and rivers are considered to be a significant part of tourism and recreation in the country. Wetlands too have the cultural significance.

1.4 Types of Wetlands

Wetlands are of two types: Inland wetlands and coastal wetlands. Inlandwetlands are important water resources refilling groundwater and sub-soil formations. Coastalwetlands include mangroves and coral reefs and they often function as natural obstructer againstsalt-water intrusion and by that protects costal land and inland water habitats. Wetlands are thesource of life. World’s biodiversity depends upon wetlands and is highly linked with them. Thatincludes many endangered and migratory species. At disaggregate level the wetlands in India are distributed in different geographical regions. They are classified in different types on the basis of their origin, vegetation, nutrient status and thermal characteristics such as glaciated wetlands, tectonic wetlands, oxbow wetlands, lagoons, crater wetlands, salt water wetlands, urban wetlands, pond/tanks-man made wetlands, reservoirs and mangroves etc. On the basis of physical location the wetlands of India may be further divided as Himalayan wetlands, Indo-Gangetic wetlands, Coastal wetlands and Deccan wetlands.

1.5 Ramsar Convention and Sites

Efforts have been made at domestic as well as at international level to provide a proper mechanism to prevent the over exploitation of wetlands. Since the diversity of the wetlands is high thus the conservation measures can be different accordingly. The Ramsar convention and the Convention on Biological Diversity (CBD) are the two unique steps towards the conservation of wetlands. Ramsar convention was adopted in 1971. It is the oldest and first intergovernmental conservation convention. The convention provide for the conservation of wetlands which are having international importance especially as waterfowl habitat. It came into being due to serious decline in population of waterfowl and need for conservation of habitats of migratory waterfowl. The convention also provides the framework for national action and international cooperation for the conservation and wise use of wetlands and its resources including biodiversity. The Ramsar Convention entered into force in 1975 and from all over the world contracting parties joined it. Wetlands that are on the Ramsar list of International importance often provide habitat for wild life whose values is not expressed in monetary terms but whose aesthetic and biological diversity value is nonetheless recognised world-wide. Convention on Biological Diversity (CBD) was formed during Rio earth summit in 1992. India joined CBD in May 1994. The objectives of the convention are: Conservation of biological diversity, sustainable use of components of biological diversity and Fair and equitable sharing of benefits arising out of utilization of genetic resources.

1.6 Wetlands of India

According to National Wetland Atlas (2011) India has more than 2 lakh wetland greater than 2.5 hectare area and about 5.5 lakh less than 2.5 hectares. The extent of wetlands has been estimated to be 15.26 million hectare. The inland wetlands account for 69.22 per cent (10.56 million hectares), whereas the coastal wetlands account for 27.13 per cent (4.14 million hectares) and other wetlands 4 per cent. Around 50 per cent of the earth’s wetlands are estimated to already have disappeared worldwide over the last hundred years. In terms of the proportion of the geographical area, Gujarat has the highest proportion (17.5 per cent) and Mizoram has the lowest proportion (0.66 per cent) of the area under wetland.The table 1 and figure 1 shows the state wise wetlands of international importance under Ramsar Convention.

Table 1 List of Major Wetlands of International Importance under Ramsar Convention

Source: Ministry of Environment and Forests, Government of India

1.7 Environmental Threat to Wetlands

Wetlands in India, as elsewhere are increasingly facing severe anthropogenic pressure. Thus, the rapidly expanding human population, large scale changes in land use and land cover development projects and improper use of watersheds have all cause a substantial decline of wetland resources of the country. Significant losses have resulted from its conversion threats from industrial, agricultural and various urban developments. Unsustainable levels of grazing and fishing activities followed by uncontrolled discharge of waste water, industrial effluents, surface run-off etc. results in the proliferation of aquatic weed affect the flora and fauna which ultimately leads to the loss of and degradation of wetlands. Restoration of these converted wetlands is quite difficult, once these sites are occupied for non-wetland uses. As per an estimate, India will lose about 84.0 per cent of coastal wetlands and 13 per cent saline wetlands with climate change inducedsea water rise of 1 metre.

1.9 Wetland Conservation and Management

Several legislations have been enacted which have relevance to wetland conservation, these includes, Forest Act 1927, Forest Conservation Act 1980, the Wildlife Protection Act 1972, the Air (Prevention and Control of Pollution) Act 1974. India had set up 505 wildlife sanctuaries and 100 national parks, 14 biosphere reserves, 6 heritage sites, projects on tiger and elephant conservation with the objective of effective conservation of wetlands.In 2006 the National Environmental Policy first recognized the need of legal regulatory mechanismfor protection of the wetlands from degradation. After many meetings the draft of Guidelines wasprepared. The Draft 2008 ‘Regulatory Framework for Wetland Conservation’ was made available forcomments and suggestions.In May 2010, another draft of Regulatory Framework was put out for comments, which included thedraft Rules, 2009. Again several comments and suggestions were sent to Ministry of Environment and Forest (MoEF) and finally on the2nd December 2010, the Union Ministry of Environment and Forests notified the Wetlands(Conservation and Management) Rules 2010, thus the rules became a law. In March this Year central government of India has come up with some new set of rules to protect wetlands. The Draft Wetland (Conservation and Management) Rules, 2016, which seeks to replace the older Wetland Rules, 2010 are open for public comment. One of the reasons cited for bringing in the new rules has been ineffective implementation of the 2010 Rules.

1.9 Conclusion

Wetlands are amongst the most productive ecosystems on the earth. Historically, they have been at the centre of evolution of human civilisation for millennia as they are means of precious ecological goods and services. The conservation of wetlands is very important by that the ecosystem can be balanced. The decreasing number of wetlands led to the evolution of various legal conventions with major aim to conserve the wetlands.

Source: Wetlands, 2007

Fig. 2

Source: Adam, 2012  fig 3                     

Fig.4 Floating Hotel in Loktak Lake

Source: http://www.thebetterindia.com/wp-content/uploads/2016/01/loktak-lake1.jpg

         

Fig. 5 A Panoramic View of TsoMorari Wetland

Source:https://i1.wp.com/vargiskhan.com/log/wp-content/uploads/2012/08/tso-moriri-2.jpg

Fig. 6 Anthropogenic Activities in Wular Lake

Source: https://www.holidify.com/images/compressed/attractions/attr_2176.jpg

Fig. 7 Bird nesting at Pongdam Wetland

Source:http://4.bp.blogspot.com/-7TjN

    2. Mangroves

Structure

2.1 Introduction

2.2 Defining Mangrove

2.3 Significance, Importance and Benefits of Mangrove

2.4 Mangroves : World Scenario

2.5 Mangroves : Indian Scenario

2.6   Flora and Fauna of Mangrove Ecosystem in India

2.7 Threats to Mangrove

2.8 Conservation and Restoration of Mangroves

2.9 Conclusion and Suggestions

2.1 Introduction

The word ‘Mangrove’ is considered to be a combination of the Portuguese word ‘Mangue’ and the English word ‘grove’. The term mangroves refer to anecological group of halophytic (Mangroves are salt-tolerant plants of tropical and subtropical intertidal regions of the world) plant species which isknown as the salt tolerant forest ecosystem andprovides a wide range of ecological and economicproducts and services, and also supports a variety ofother coastal and marine ecosystems.The specific regions where these plants occur are termed as ‘mangrove ecosystem’. These are highly productive but extremely sensitive and fragile. Besides mangroves, the ecosystem also harbours other plant and animal species. Mangroves are among the oldest and most productive wetland forests on our planet. Found in the intertidal zone, they are uniquely adapted to survive highly saline and anoxic conditions. They are ideal habitats for many terrestrial and marine species, carbon sinks and natural barriers against storm surges and coastal erosion.Mangroves provide invaluable services but have been declining worldwide as a result of anthropogenic and other threats.

    2.2 Defining Mangrove

‘Mangrove’ has been variously defined in literature. The oxford dictionary mentioned the words ‘mangrove’ and ‘mangrowe’ since 1613, indicating tropical trees or shrubs found in coastal swamps with tangled roots that grow above the ground, whereas the Americans, the Spanish, and the Portuguese used the term ‘Mangle’ and ‘Mangue’ indicating trees and shrubs of the genus Rhizophora (Mepham&Mepham, 1984). Later, the term ‘mangrove’ was referred to the individual plant or tidal forest or both, as ‘Mangrove plants’ and ‘Mangrove ecosystem’ (MacNae 1968).

2.3 Significance, Importance and Benefits of Mangrove

Mangrove ecosystem is self-maintaining, self-repairing, self-sustaining and most productive. Mangroves form very important part of the marine food chain. They help in recycling the nutrients in coastal waters. They help to control pollution through a process called rhizo-filtration. They are the source of wood and have unexplored potential for natural products. Mangroves helps to trap debris, silt and stabilizes the coastline. They also provide opportunities for education, scientific research, eco-tourism and socio-economic studies. The ecological importance of mangrove comes from protecting the coast from cyclones, strong wave action, floods, sea level rise, green house effect and coastal erosion. The habitat provides the breeding and nursery grounds for many of the marine (crustaceans, molluscs, fin fishes etc.) and terrestrial animals (birds, bees and other wildlife). However during the recent decades mangrove resources have been over exploited, particularly reclaimed by diking, draining, land filing for residential, commercial, industrial, agricultural and real estate purpose.

2.4 Mangroves: World Scenario

Mangroves occupy less than 1 % of the world’s surface and are mainly found between the Tropic of Cancer and the Tropic of Capricorn on all continents covering an estimated 75 percent of the tropical coastline worldwide. There are more than 18 million hectare of global mangroves inhabiting in 112 countries and territories in the tropical and subtropical region. Around 34 major and 20 minor mangrove species belonging to about 20 genera in over 11 families have been recorded globally. Mangroves of South and Southeast Asia form the world’s most extensive and diverse mangrove systems comprising 41.4 percent of global mangroves. Indian mangroves make up 3.1 percent of the total global cover and are distributed along all the maritime states, except the union territory of Lakshadweep, covering an area of about 4461 km2 along the 7,500 km long Indian coastline (Saenger, 2002; Tomlinson, 1986).

2.5 Mangroves: Indian Scenario

Mangroves in India account for about 3.1 per cent of the world’s mangrove vegetation and are spread over an area of about 4461 km2 along the coastal States/UT of the country. Sunderbans in West Bengal account for a little less than half of the total area under mangroves in India. After West Bengal, Gujarat and Andaman and Nicobar Islands have maximum mangroves. In India, mangroves occur on the West Coast, on the East Coast and on Andamanand Nicobar Islands, but in many places they are highly degraded. According to theGovernment of India (1987), India lost 40 percent of its mangrove area in the lastcentury. The National Remote Sensing Agency (NRSA) recorded a decline of 7000 ha ofmangroves in India within the six-year period from 1975 to 1981. In Andaman and Nicobar Islands about 22400 ha of mangroves were lost between 1987 and 1997.India with a long coastline of about 7516.6 km, including the islandterritories, had a mangrove cover of about 6749 km2, the fourthlargest mangrove area in the world. However, a recent assessmentshows that India has a total mangrove cover of only 4628 km²or 0.14% of the country’s land area, 3 per cent of the global mangrove area, and 8 per cent of Asia’s mangroves., of which about 60 per cent is along the eastcoast (Bay of Bengal), 27 per cent is along the west coast (Arabian Sea) andthe remaining 13% is in the Andaman and Nicobar Islands. Thesemangrove habitats (69°-89.5°E longitude and 7°-23°N latitude)comprise three distinct zones: east coast habitats having a coast line ofabout 2700 km, facing Bay of Bengal, west coast habitats with a coastline of about 3000 km, facing Arabian sea, and Island Territories withabout 1816.6 km coastline. The state of West Bengal has the maximumcover (2,097 km2), followed by Gujarat (1103 km2) and the Andamanand Nicobar Islands (604 km2).India’s mangroves can be broadly categorized into deltaic,backwater-estuarine and insular types according to Thom’sclassification of estuary habitats. Deltaic mangroves are found alongthe east coast within the deltas of the Ganges, Brahmaputra, Mahanadi,Krishna, Godavari and Cauvery rivers. Estuarine mangroves are foundon the west coast in the estuaries of the Indus, Narmada and TaptiRivers. They are also growing in the backwaters, creeks and neritic inletsof these areas. Insular type of mangroves is found in the Andaman andNicobar Islands. The table 2 shows the state wise list of major mangroves sites of the country.

Table 2 State Wise Major Mangrove Sites in India

Source: Ministry of Environment and Forests, Government of India

Source: Based on table 2Fig. 8

    2.6 Flora and Fauna of Mangrove Ecosystem in India

The Mangrove in India is home to numerous species of flora and fauna and the presence of Mangrove ecosystems on coastline can save lives and property during natural hazards like cyclones, Tsunami, storm surges and erosion, as well. The Mangrove in India is home to a large number of over 1600 plant and 3700 animal species. The most notable species of Mangrove in India include the major components like “Acanthaceae“, “Avicenniaceae” or “Verbenaceae” (Black mangrove), “Combretaceae” (Buttonwood, White Mangrove), “Arecaceae” (Mangrove Palm), “Rhizophoraceae” (Red Mangrove), “Lythraceae” (Mangrove Apple) etc. families.The Indian mangroves comprise approximately 59 species in 41 genera and 29 families. Of these, 34 species belonging to 25 genera and 21 families are present along west coast. There are about 25 mangrove species which have restricted distribution along the east coast and are not found on the west coast. Similarly, there are eight species of mangroves like Sonneratiacaseolaris,Suaedafruticosa, Urochondrasetuloseetc. which have been reported only from the west coast. There areapproximately 16 mangrove species reported from the Gujarat coast, while Maharashtra has about 20 species, Goa 14 species and Karnataka 10. There are hardly three to four species of mangrove which are rarely found along the Kerala coast. The associated mangrove flora is quite common to both the coasts, with minor variations in distribution. The floral diversity of mangroves of India is comprised of 38 core mangrove species (Kathiresan, 2003).

2.7 Threats to Mangrove

The threats to the mangrove ecosystem could be broadly grouped into two: Natural and Anthropogenic. These factors may affect the system as a whole or any one entity within the system, etc. The natural threats include: Climatic changes, Cyclones and Physical processes. Diseases, deterioration, pollution, grazing, agriculture, aquaculture and human encroachment (including reclamation), etc. are considered as the anthropogenic threats to the ecosystem. Mangroves also face threats from poorly planned human settlements, improper location of industries and infrastructure, pollution from industries and settlements, overexploitation of living natural resources, inadequate institutional capacities for and participation of local communities in formulation and implementation of coastal management plans.

2.8 Conservation and Restoration of Mangroves

     The mangrove habitat continues to decrease around the world at an alarming rate. Constant measures are required to be taken to prevent deforestation of mangrove forests. Regular monitoring of these areas to control illegal felling of the trees should be implemented. The conservation and management of mangroves by national governments, NGOs and local communities started around the world during 1990s. Government of India declared these areas as ecologically sensitive areas under the Environment(Protection) Act, 1986 putting a ban on their exploitation and by the CRZ Notification 1991 prohibiteddevelopment activities and disposal of wastes in these areas.Need for policies and interventions became necessary in many countries as they virtually had no policies for management of mangroves or failed in enforcing the conservation policies and protection measures. The major breakthrough for the development and restoration of mangroves started since 2005 when Tsunami struck the Indian Oceans on 26 December 2004. But the concern of Government of India for the conservation of forest and wildlife was clearly visible by a 1976 amendment to the Indian Constitution, which states that, it shall be the duty of every citizen of India to protect and improve the natural environment including forest, lakes, rivers and wildlife. The government of India has set up the National Mangrove Committee in the Ministry of Environment and Forests, New Delhi in 1976 to advise the government about conservation and development. This committee put forwarded certain schemes for conservation such as identification of selected mangrove areas for conservation, preparation of a management plan, promotion of research, adoption of multidisciplinary approach involving state governments, universities, research institutions and NGOs. Then in 1979 the National mangrove Committee further recommended the nationwide mapping of mangrove areas, quantitative surveys of areas, rate of growth of forest trees, assessment of suitable sites for reserve forests, afforestation of degraded mangrove areas, study of management methods, the ecology of mangroves, their flora andfauna, their microbiology and the biochemistry of organic matter andsediments.Ministry had made a plan-scheme forconservation and management of mangroves in 1986 and constituted National Committee toadvise the Government on relevant policies andprograms. Due to their recommendations 15 mangroveareas in the country were identified for intensiveconservation (Jagtap et al., 2002).Even before the year 2005 when tsunami struck the coast of India the initiative was also taken by MSSRF (MS Swaminathan Research foundation). TheMSSRF launched a major programme in 1996 for restoration ofmangrove wetlands of the east coast of India, with financialsupport under the India Canada

Environment Facility (ICEF) andin collaboration with the Ministry of Environment and Forestsand State Forest Departments of Tamil Nadu, Andhra Pradesh,Orissa and West Bengal. India recorded a net increase of 23.34 sq. km of mangrove cover between 2009 and 2011, thanks to efforts of one of the most industrialized states, Gujarat, in planting and regenerating the ecosystem rich in biodiversity.

2.9 Conclusion and Suggestions

Proper monitoring is imperative to prevent illegal activities such as poaching of mangrove fruits, fishing activities, movement of barges etc so that young plants do not get damaged, fish germplasm is not depleted. Fisheries should be encouraged with proper vigilance and legislation so as to avoid damage to the existing mangroves. Along with the restoration work, awareness should be campaigned, educational materials should be made available to improve knowledge on mangrove habitats, resources, relevant legislation, policies and conservation strategies with the help of media like magazines, films, posters, pamphlets, documentary, exhibitions, bird watching tours, study tours, competitions on mangrove knowledge etc.

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