GENERAL ARTICLES Human-mangrove conflicts V. P. Upadhy 1y*, Rajiv Ranjan and J. S. Singh Mangrove resources are available in approximately 117 countries, covering an area of 190,000 to 240,000 km’. Countries like Indonesia, Nigeria and Australia have the largest mangrove areas. These ecosystems harbour 193 plant species, 397 fishes, 259 crabs, 256 molluscs, 450 insects and ‘more than 250 other associated species. Mangrove ecosystem has the highest level of productivity among natural ecosystems, and performs several ecosystem services. The continued exploitation of mangroves worldwide has led to habitat loss, changes in species composition, loss of biodiversity and shifts in dominance and survival ability. Worldwide, about half of the mangroves have been destroyed. The Indian mangrove biodiversity is rather high. The increase in the biotic pressure on mangroves in India has been mainly due to land use changes and on account of multiple uses such as for fodder, fuel wood, fibre, timber, alcohol, paper, charcoal and medicine. Along the west coast alone, almost 40% of the mangrove area has been converted to agriculture and urban development. Our understanding of the natural processes in this vulnerable and fragile ecosystem is far from adequate. Environmental awareness, proper management plan and greater thrust on ecological research on mangrove ecosystems may help save and restore these unique ecosystems. terrestrial ecosystems. The extent of wave and tidal eoping between mangrove and offshore marine biotopes controls the intensity of interaction between the systems'. These ecosystems are effective in storing large amounts of inorganic and organic nutrients which are washed into ANGROVE ecosystems are open systems which exchange ‘matter and energy with adjacent marine, freshwater and 'V. P. Upadayay is in the Fastem Regional Office, Ministry of Envi tooment and Forests, Bhubaneswar 731 023, India; Rajiv Ranjan isin the Forest Deprment, Dnarwad, India J. 8. Singh i i the Dept ‘meat of Bouny, Banaras Hind University, Varanasi 221 008, India, ‘For soreespondence. e-nsil:ypupadiyay@ houmal om) 28 mangroves from the rivers and continental drainage. They also process huge amounts of organic matter, dis- solved nutrients, pesticides and other pollutants which (CURRENT SCIENCE, VOL. 83, NO, 11, 10 DECEMBER 2002GENERAL ARTICLES are dumped into mangrove areas due to anthropogenic activities, These ecosystems occur on coastal lowlands of tropical and subtropical intertidal region and near river mouths. Mangroves are found between latitudes 32°N and 38°S along the tropical coasts of Aftiea, Australia, Asia and America, They grow in high- and low-tide areas and experience the altemation of ebb and flow. Mangrave forests once covered three-fourths of the coastlines of the tropical and subtropical countries, of which less than '50% remains today, and half of the remaining forests are degraded’. Scientific knowledge on the structural and functional characteristics of the mangroves and the natu- ral processes operating in these vulnerable and fragile ecosystems, is rather poor. ‘The present article highlights the ecological stresses in mangrove ecosystems and traces the causes of their degradation. The management issues have been explored ‘and certain strategies for conservation and restoration of ‘mangrove ecosystems are indicated. Mangroves and mangrove ecosystem ‘The term mangrove refers to an ecological group of halo- phytic plant species as well as to a variety of complex plant communities dominated by these species, found along sheltered tropical and subtropical shores. Globally, the mangroves are estimated to include 16-24 families nd S4-75 species’. The earliest mangrove species appear to have originated in the Indo-Malayan region and sub- sequently spread with the help of their floating fruits, seeds and seedlings, both westward and eastward, occu- pying the relatively sheltered lagoons, estuaries and quiet backwaters. Evolutionary adaptation to coastal marine environments, characterized by brackish water and muddy substrata in the intertidal zone, led to such characters as prop roots, knee roots, plank buttresses and pneumato- ‘Table phores, sclerophyllous leaves with sunken stomata, and Vivipary. The control of tissue water potential through specialized leaves and stems, exclusion of salt through thizofiltration and excretion through leaf salt glands, and the ability to deposit salt in older leaves, bark and pneu- ‘matophores, conferred a high level of salt tolerance™. ‘The dominant salt-tolerant, sclerophyllous broadleaved trees form a unique ecosystem with associated plants, including epiphytic and terrestrial ferns, orchids, lichens, non-mangrove halophytes, sea grasses and seaweeds, and fauna such as fish, shrimp, shellfish, crabs, lobsters, reptiles and birds, The mangroves make an enormous contribution to the food chain that supports the coastal fisheries. These ecosystems are quite productive (350- 500 gC-m yr)’ and may show a strong, weak or no spatial zonation“, although the abundance of individual species may follow the gradient of salinity’. Most of the species are quite plastic to salinity, and prefer a salinity range of $-30 parts per thousand, Mangroves can be divided into New World and Old World groups’. The New World group includes North, Central and Southern America, and Western Africa. Ten dominant mangrove species available in these regions are not found in the Old World group. In the Old World, ‘mangroves are confined to the Persian Gulf, Madagascar, Indo-Malaysian and Australian regions. India, Pakistan, Bangladesh, Myanmar, Indonesia, North Australia and Papua New Guinea represent the Indo-Malaysian group. Sixty-five mangrove species found in the Old World ‘group are not present in the New World group", ‘The mangrove forests are found in approximately 117 countries. There is a lack of exact statistics on the global ‘and regional extent of the mangrove area. According 10 the report of the World Resources Institute’, mangroves cover an area of 190,000 to 240,000 km?, occupying about one-quarter of the world’s coastal line, Largest ‘mangrove areas occur in Indonesia (30%) followed by Mangrove extet and lost in selected counties (Source raf 9) ‘Curren extent Approximate Region and county (= 10h) percent Peso covered Ind 100-700 50 1963-77 Peninsular Malaysia 98.3, 17 1965-85 Philippines M0 + 70 1920s to cites 1990 Singapore 05-06 _ 20-30+ Provgricultural period to preseat Thailand 1964-687 25197987, Views 200 501943 w early 1990s Latin Ameroa Pacts Rico 75 Prewolonal to present 30+ Presgoiealtaral o present 302 1965°30 06 Kenya 30-616 GuinenBissay 236.6 ibe 20 ‘CURRENT SCIENCE, VOL. 83, NO. 1, 10 DECEMBER 2002 40 Pre-agricutual vo mid-1980s 40 Pre-agricatual to mid-1980s 75+ Precaricultual wo mid-1980s 70 Pre-aricaltual to mid-1980s 1329GENERAL ARTICLES Nigeria (10%), Australia (8%) and Mexico (7%). India contributes approximately 3% to the world mangrove area, Table I includes estimates of the extent of mang- roves in selected countries. Status of Indian mangroves The Indo-Malaysian region is considered as the eradle of evolution of mangrove vegetation". Its believed that India was under the Tethys sea which, by the end of the Creta- ceous, started receding, and the present Indian position Table 2. ‘came into existence in the Miocene, about $5 my. ago. Even prior to this period (i.e. from Cretaceous to Mio- ene) mangrove vegetation occurred luxuriantly along the Indian coast according to available fossil records! ‘According to one estimate, the mangrove forest cover in India has reduced from 6000 km” in 1953 to 2000 3000 km® in 1989 (ref. 12). These forests now occupy an area of about 4871 km? afea. The district-wise mangrove forest cover'™" is given in Table 2. These forests are found in the river basins of the Ganges, Brahmaputra, Mahanadi, Godavari, Krishna and Kaveri. The east coast Diswiet-wise mangrove forest cover in India (based on refs 13 and 14) ‘Avoa assessment (ham) sate Distt Andaman and ‘Nico Islands ‘Andamans Nicobar Tol Andhra Pradesh Godavari Krishna Nellore, Prakasim, Kurnool Guatur Total Goa Gujarat Bharuch Bhavnagar Jamnagar Kachehit Kamataka Mabacashica Mumbai ciy Murbai Colaba Thane Raigarh Ratnagiri Tosa Orisa Baleshwar Bhadrak Togatsinghpur Ki West Rengal® ‘Tamil Nad South Arcot Thanjavur, Trchicapall, Pudakkoti Total Grand total *Distitavive data for 1997 not reported 1330 Change from Change from 19971999 199S assessment 1997 ateesement 09 2 9656 Nil Nil ee esa 397 +5 +14 5 5 +2 Nit B 20 us 836 4 991 +302 +40 2 1 3 + Nit 46 PY 2 ia —u -16 3 0 0 181 a +16 +4 a 29 2093 2s 2125 +4 +2 Go 12413) 1 Nil Nil 471 +294 +48 ‘CURRENT SCIENCE, VOL. 83, NO. 11, 10 DECEMBER 20n2GENERAL ARTICLES is endowed with the world’s largest mangrove forest, with Gangetic Sunderbans in West Bengal having the largest area under mangrove forest (2125 km*). The Forest Survey of India data indicate that in most of the states, mangrove forest cover has gained or has remained tmchanged since 1995, except for Maharashtra which continues to lose these forests (47 km? lost since 1995). Nevertheless, large stretches in almost all mangrove areas in the country are in severely degraded conditions, having reduced or negligible vegetal cover. ‘An Indian National Mangrove Management Committee was formed by the Ministry of Environment and Forests, to collect more ecological data and information, and to evolve a management plan for mangroves. This commit. tee recommended @ nation-wide mapping of the mangrove area, preferably by remote sensing coupled with land surveys and time-series data to make an assessment of the rate of degradation of mangrove ecosystem'’. The Space Applications Centre, Ahmedabad in collaboration with various coastal state agencies, carried out the map- ping of the coastal wetlands using landsat TM/RS LISS IE data in 1 : 250,000 scale for the entire Indian coast and in | : 0,000 seale for all coastal states" Floristic diversity ‘The species diversity is higher in the Indian mangrove ecosystems compared to that of Latin America and Africa. Large physical forces in tide water, salinity level and lack of stable substratum are some of the natural fae- tors which affect the species diversity. The status of eco- logical investigation of Indian mangroves is so poor that it is difficult to get correct information on species num- ber and diversity. One hundred and sixteen plant species have been recorded by Banerjee et al.'” which include 59 mangrove species, 47 algae and 10 species of sea grasses, About 65 vascular plant species belonging to 31 families and 59 genera have been reported from the mangrove ecosystems of India. The east coast has 64 vascular spe- cies from 42 genera and 29 families. The west coast has 33 species from 24 genera and 19 families, and Andaman and Nicobar Islands represent 43 species from 30 genera and 23 families’. Bight species of mangroves occurring ‘on the east coast afe not represented in the mangrove areas of the west coast, Reports indicate that Sunderbans alone has 62 species'*. Families Combretaceae, Rhizo- phoraceae and Avicenniaceae predominate. Major genera include Avicennia, Acanthus, Acrostichum, Aegialitis, Aegiceras, Brownlowia, Bruguiera, Caesalpinia, Cer bora, Ceriops, Clerodendron, Cynometra, Dalbergia, Dervis, Dolichandrone, Excoecaria, Finlaysonia, Heri- tiera, Hibiscus, Hoya, Imsia, Ipomoea, Kandelia, Lum- nitzera, Merope, Mucuna, Myriostachya, Nypa, Phoenix, Porteresia, Rhizophora, Salvadora, Sarcolobus, Scyphi- hora, Sonneratia, Thespesia, Tylophora and Xvlocarpus. Mangrove vegetation also includes several ferns, orchids, ‘CURRENT SCIENCE, VOL. 83, NO. 1, 10 DECEMBER 2002 palms and sedges. The lack of systematic and ecological studies, and availability of only fragmented information ‘on Indian mangrove ecosystems warrants a comprehensive research plan, Animal diversity Mangrove areas harbour a variety of fish and prawn spe- cies. Robertson and Blaber"” reported 26 to 197 species in tidal forests, Odum and Heald?” collected a large num- ber of fishes, crabs and insect larvae from mangroves in southern Florida. Fifty-three species of fishes, five spe- cies of Decapoda, five species of Amphipoda and 3-80 species each of Isopod, Cumacea, Mysidecea, Copepoda, Ostracoda, Mollusca, Ciliata and Chironomid larvae were identified. About 400 species of fishes are reported to depend on mangrove habitat’, A more comprehensive data set produced by Rao” indicates that mangrove eco- systems of the world have 193 plant species, 397 fishes, 259 crab species, 256 molluscan species, 450 insect spe- cies and more than 250 species of mammals and other associated species of plants and animals. Indian mangrove areas are excellent nursery grounds for a variety of commercially important prawns, crabs and fin-fishes, as they provide abundant food and shelter for these organisms. These ecosystems provide food, roosting and nesting site and shelter to a large variety of birds. The evergreen canopies of mangroves are inhabited by several insects, reptiles, birds and mammals. The ‘mangroves support many trophic levels of aquatic and ter~ restrial organisms, by enriching the fertility of estuarine waters for production of planktons. Table 3 summarizes the faunal diversity in Indian mangrove ecosystems. ‘The conflicts ‘The mangrove ecosystem provides a variety of ecosystem services; their economic value, if calculated, would be staggering. These services include prevention of coastal erosion, barrier against typhoons, cyclones and hurri- canes, protection of coral reefs from siltation, and soil Table 3. Fauna diversity in mangrove forests of Lada (based on wef. 33) “Taxonomic goup West coast Crustaceans 229) Molluscs = Wood borers 26 Fishes 105 Reptiles 3 Binds 47 19 Marimals 36 2 Microbentios Mm Shellfshes 2» ‘Esimates not available 1331GENERAL ARTICLES accretion (Figures 1-3). Indirectly, forests are responsible for extension of islands. These systems act as biological ‘waste-water treatment plants, lowering the biological oxygen demand (BOD), and possibly performing bio- remediation by removing toxic elements. These forests also provide breeding, nursery and feeding grounds for harvestable marine fauna”. Pecuniary benefits include wood for fuel, furniture and construction, green leaves and fruits for fodder, source for charcoal, tannin, paper, dyes and chemicals, thatch, honey and incense. Good quality of charcoal is produced from the wood of Rhizo- ‘phora species, The foliage of mangrove species is used as fodder for cattle, camels and goats. Avicennia is largely used as fodder for camels and other cattle as it grows in the arid region of Gujarat as well as in Konkan and Goa". Over-exploitation for these pecuniary benefits has led to mangrove degradation at many places. Several mangrove plants are used in indigenous medi- cine, such as Bruguiera gymnorrhiza for diarthoea and Figure mangroves act a5 aural ‘Tropical foress of litle Andamans. Coastal fores and nisin prevention of coastal cresion and | acta a baie agains: cyclones. wre 2. Mangroves on creeks lel providing breeding, misery and foadng grounds fou varity of brackishewater and inane fata 132 blood pressure, Rhizophora mucronata for angina, Acan- tus ilicifolius for asthma and theumatism, Lumnitzera racemosa for herpes and itches, and Cynometra ramiflore and Excoecaria agallocha for leprosy***. These plants are used for curing elephantiasis, abdominal troubles and skin diseases”, They also cure sores, leprosy, headaches, rheumatism, snake bites, boils, ulcers, diamhoea and haemorrhages”. ‘These unique coastal, tropical forests are now among the most threatened habitats in the world, due to expand- ing human population and resultant unsustainable eco- nomic development. Exploitation for firewood, charcoal and timber, deliberate land reclamation for urban and industrial development, shrimp farming and dumping of pollutants include the serious causes of mangrove forest loss. Shrimp farming alone caused a loss of 65,000 ha of mangroves in Thailand”. Java has lost 70% of its mangrove area, Sulawesi 49% and Sumatra 36% (ref. 30). Globally, the rate of decline in mangrove forest cover is estimated at 2-8% yr! (ref. 31). According to a study", 70% of the total coastline in Europe and Asia are under high potential threat of degradation. World’s average coastline under the above category is 34%, Due to various types of coastal developmental activities, 75% of marine protected areas each in Asia ‘and Europe and 68% in Africa are at high risk of degra- dation’. Table 1 includes estimates of loss of mangroves for selected countries, During the last three decades, as much as 40% of the ‘mangrove area has been converted to agriculture or urban centres along the west coast". As a result of continuous biotic pressure, the mangrove and other marine resources are experiencing habitat loss, changes in species compo- sition, shifts in dominance, loss in biodiversity and threat to survival. Some of the mangrove species are on the way to extinction from the west coast. Examples are Xylocar- pus granatum, Bruguiera eylindrical, Sonneratia acida and Cynometra ramiflora. Similarly, Nypa fruticans, Figure 3. Root stuctue of mangroves helps in preventing coastal crotion and soil accretion. Mangroves act as an eco-one between ‘squat wd and babitats ‘CURRENT SCIENCE, VOL. 83, NO. 11, 10 DECEMBER 2002GENERAL ARTICLES Heritiera minor and H. formes have all but disappeared {rom the Sunderbans. Activities like bunding, erosion and deposition cause changes in the tides and currents, which in tum have strong impact on mangroves in particular and coastal ecology in general. The herbicides and defoliants applied in the coastal crop lands are polluting the mangrove habi- tats through surface run-off. Mangroves are very sensi- five to these types of chemicals™, The mangroves have a large capacity to metabolize organic wastes and have been termed as natural sewage-treatment works. They ‘can utilize the excess nutrients to increase the producti- vity. However, continuous excessive inputs of nutrients may adversely affect the ecology of mangroves". Table 4 summarizes the pressures on Indian mangrove eco- systems! The mangrove vegetation of Kavery delta has substan- tially suffered due to geomorphic and anthropogenic interferences". Narayanan’” has observed simultaneous sedimentation and erosion in Pichavaram mangrove areas. Structural changes have been noticed in Pichavaram and Muthupet areas due to clear felling, reduction in fresh- water and tidal water inflow", The above study also recorded 5-30% and 20-60% degraded mangrove vegeta- tion out of 6986 and 6559 ha of mangrove area respec- tively, in Bhitarkonika and Mahanadi sites. in Orissa About 20 villages in Mahanadi area and 59 villages in Bhitarkanika aren depend on mangroves for ther livel hood. In Orissa, the mangroves from Chilka, Hetamaindia, Kujang and from estuaries of Subemarekha and Satadhar have already disappeared. The forests of Bagapatia and Sunei-Rupei were cleared for rehabilitation purposes”, The conflicts between traditional and commercial fishing practices are also @ major factor contributing to mang rove degradation Conservation strategies Legal provisions ‘The Ministry of Environment and Forests has notified Coastal Regulation Zone (CRZ) to regulate various activities in coastal areas. The coastal zones (up t© 500 m from high tideline towards the landward side) have been ‘Table 4. Biotic and oer pressures on Indian mangrove ecosystems Sateiarea Presse Gujarat Gulf of Kachoha Gulf of Kambhat South Gujarat Mabacashica “Thane, Raj and Dharmatar Creks, ‘Murai region, Mabimn Esuary Karnataka ‘Kali, Honavara, Bhat Mangalore Kerala Cochin backwater Veranad Estuary Tani Nadu ‘Vella Estunry, Muthupes, Adyar and Fanore Goa “Mandovi Estuary Andhra Pradesh ‘Machilipatsac, Polakayatipa, Tutipalar, ©: ‘Bhitarakanita,Jatadhar, Muben Devi River, Balasore West Benga Sunderbans, Sagar Island, Hooghly Estuary Malia Andaman and Nicobar Islands Continuous grazing, timber and fuel wood harvest, erosion of shorlin, industrial inspact, gazing pressure Marine National Pack activities, stuted growth, barren, In many ass suated and sprse 4vicennia marina Coral reef degradation, conversion of high tidal mod-ats into sgrcultte and residential developinent Industrial pofuton and domestic sewage, erosion Deposition and exosion Sparse in all areas, reclamation of backwaters Developmenial activites, indiscriminawe euting for Mel wood, biopollution Erosion, ture and aga it cutting fr timber and fuelwood, grazing, aquacu tre eMuets, sceumultion of heavy metals Higher concentsation of dissolved metals, mining Erosion land reclamation Shore culture change, settlements, conversion for agriculture, aquar Huge exploitation of Phoenix paludosa, erosion and deposition, Paper and petrochemical eMuents| Rec ian and deforestation for agriculture ‘CURRENT SCIENCE, VOL. 83, NO. 1, 10 DECEMBER 2002 133GENERAL ARTICLES classified into four categories on the basis of ecological sensitivity and development along the coast. The CRZ-1 areas are the most sensitive ones, where no developmental activity is permitted. In CRZ-II areas, certain develop- ‘mental activities are permitted on the landward side of the existing rondistructure. No activity is permitted towards the seaward side of the existing road/structure. In CRZ-IIL areas, no construetion is allowed up to 200m from high tideline. Beyond 200m, clearance is required to be obtained for any constriction activity. The approved coastal zone management plans of each coastal state demarcate all mangrove areas as CRZ-I, According to the above plan, all mangroves with an area of 100 m° or more are classified as CRZ-I, with a buffer zone of at Teast 50m. Thus, the CRZ notification 1991 and approved coastal zone management plans of each coastal state have clearly emphasized the importance of mangrove eco- systems by imposing restrictions on use of these sensitive areas for any developmental activity. Keeping in view the importance of mangrove ecosystem, a total ban was imposed in 1987 on felling of trees. Although legal restrictions have been imposed to pre- vent conversion of mangrove areas, these areas are still being converted due to various types of biotic pressures and developmental activities. The coastal states need to enhance vigil and take immediate action to prevent con- version of mangrove forests, The provisions of CRZ noti- fication, 1991 and coastal zone management plans need to be strictly enforced. Protected areas Establishment of protected area network is among the best conservation strategies. Mangrove areas of the coun- tty are represented in the Sundetbans Tiger Reserve, Bhitarkanika, Coringa, Nelapattu and Point Calimere Wildlife Sanctuaries and Pirotan National Park. Among these protected areas (PAS), Sunderbans has been recog- nized as a Natural World Heritage Site, However, most of these PAs suffer from a lack of manpower and infra- structure, continued human activities, and encroach- ments. Management plans for the PAs need be based on ecological principles, and should include pragmatic strategies for ecodevelopment of the adjacent areas. A research component, and inclusion of scientists in the ‘management teams are needed. A transboundary approach (India and Bangladesh) for mangrove conservation is highly desirable. Restoration ‘There is need for the forest departments to undertake hhuman-assisted restoration of those areas which have been made barren or have degraded due to biotic pres- sures or other factors, It would be advisable fo prepare @ 13H time-bound management plan, specifically for mangrove regeneration. Regeneration research must be given top priority among such management plans, Mangrove forest regeneration depends on natural seedlings. If proper pro- nis given, the system will regenerate itself. How- ver, if the habitat is completely destroyed, recovery will be difficult due to changed environmental conditions such as soil salinity, tidal pattern, altered land use, enhanced biotic pressure, efe, In such cases, intensive human assistance is needed. Most of the mangrove plants are viviparous, ie. the seeds mature and germinate on the tree, After falling, down, many of the germinated seeds drift away with the currents. The seeds may be collected from natural hab tats and directly sown in the mangrove areas during low tide period, generally at a spacing of 30m x 30cm. Seedlings can also be raised in nurseries near natural habitats under partial shade. Seedlings can be raised in standard polyethylene bags with the soil of mangrove area as the medium. Preference should be given to the soil where the seedlings are going to be planted, Such seedlings should be irrigated with brackish water. It is desirable to keep the seedlings in the nursery for about ‘nine months before transporting them to the planting site ‘The plantation should be raised during the premonsoon showers, preferably at a spacing of 1 m* 1m, in 30cm’ pits ‘Some efforts have been made to raise mangrove plan- tations in degraded forests in Orissa, West Bengal, ete. by the respective Forest Departments. With adequate pro- tection, mangroves regenerate and cover the exploited area in a short period. This process needs to be augmented. with human intervention, For example, harvesting of ‘mangroves on sustained yield basis with defined period of rotation should be mandated to ensure sufficient regeneration, Clear felling of mangroves promotes fast growing of unwanted weed species which inhibit man- prove regeneration. Natural regeneration and recovery can also be pro- moted by reducing the anthropogenic pressure due 10 fuel-wood demand on natural populations. There is an urgent need to undertake massive afforestation pro- grammes with improved fuel-wood yielding trees in the buffer areas, to sustain the requirements of the local people, These plantations will act as a major energy source to local communities in future. Plantation of fast- ‘growing species, should also be taken up in the villages, which will reduce the dependence of coastal communities for conventional firewood from mangrove forests. tect Sustainable use and public participation ‘The local governments should formulate proper manage- ment policy by involving local people who have a stake in the conservation and management of mangrove forests in their areas. The mangrove areas are ideal to undertake ‘CURRENT SCIENCE, VOL. 83, NO. 11, 10 DECEMBER 20n2GENERAL ARTICLES conventional aquaculture practices which do not cause damage to the ecosystem, Small-scale community-based fisheries must be encouraged, as 95% of the coastal population is engaged in this sector. These communities use only 10% of the energy of large-scale fisheries corpo- rate sector to contribute half of the world eatch, The in- terest and rights of local communities must be safeguarded" "". The prawn-farming projects, which are established close to mangrove and estuarine areas, for eaming large sums of money in the shortest possible time, need be discouraged. Such aquaculture severely affects the ecology of these ecosystems. Silvofisheries, a form of integrated mangrove tree culture with brackish- water aquaculture, wherein the mangroves are cultured on a slightly raised central, earthen platform within the aqua- culture pond, or mangroves are maintained around the aquaculture pond units, can potentially be a sustainable ‘management strategy for integrating livelihood with con- servation. The development of a system of village com- munity forests, in which each village is given the responsibility to manage and sustain a small area of man- grove forest in lieu of accruing benefits from capture of lnrger quantities of marine fauna for food and trade as the system recovers, is also a viable conservation option. The mangrove areas can be used for the development of eco- tourism, recreation, education and for creating publi awareness on aspects of nature conservation (Figure 4). Public awareness and research Efforts should be made at village, district and state levels by the policy makers and NGOs, to educate the local people about the economic and ecological values and functions of mangrove forests, and the negative results of their mismanagement. There is a need to involve people at the grassroots level, in protection of these forests. With better management practices, they can derive their bona- fide needs of firewood sustainably. The government . ; Figure 4. Mangrove areas being rich in biodiversity and having spe= sjalized organs, may aract eco-bursm CURRENT SCIENCE, VOL. 83, NO. 11, 10 DECEM! 2002 should also encourage and involve ecologists, researchers and specialists to work on various aspects of ecological ‘management of this resource. Long-term research acti- vities should be undertaken in collaboration with various premier organizations 19 increase the productivity of mangrove forests and also to develop various manage- ment models which can give added benefits to local communities involved in protection and conservation. Research is needed to exploit the capability of artificially constructed mangrove ecosystems to lower the BOD of ‘waste water and to remove toxic elements through bio remediation, 1, Wolanski,F, Mazda, ¥. and Rid P., in Tropical Mangrove Beo- systems (eds Roberton, A. and Alongi, D. M.), Coastal and Esmarine Studies, 41, American Geophysical Union, Washington, 1992, pp. 43-62. 2. Mangrove Action Projet, ww earthisland org, 2002, 3. Tomlinson, P. B., The Botany of Mangroves, Cambridge Univer sity Press, Cambridge 1986. 4. Archbold, 0. W., Beolog of World Vegetation, Chapesan & Hall Landon, 1985 '. Mana, K. Tl, Ecology of Coastal Waters, University of California Pros, Berkeloy, 1982. 6, Ellison, A. M, Mukherjee, B. B. and Karim, 14 813-904, 1. Helalsddigui, AS. M, fndion J Por, 1999, 22, 197-202 8. Banerjee, LK. and Ghosh, D., in dm Anthology of Indian Mangroves, ENVIS. Publication, Annamalai Univesity, 1998, pp. 20-24 9. World Resouress: A Guide 19 the Global Environment, Oxford Universiy Press, World Resources Insite, Washington DC, 1996-97 10. Krishnamurthy, K., The Mangroves, ENVIS, Annanlai Univer sig, 193. vo. Bs pp 13, 1. Kathiresan, K., Seshaivana, 1998, 8, 15-19. 12. Marine Protected Area News in South Asian Seas Region, Indio, IUCN, Gland, Switrerand, 1998, vo. 2. 13, State of Forest Report, 1997, Forest Survey of India, Debra Dun, 1997 14, State of Forest Report, 1999, Forest Survey of India, Debra Dun, 1999, 15. Mangroves in Inia (Status Repon), Ministry of Environment and Foresis, Govt af ldia, New Deli, 1987 16. Coastal Environment, Space Applications Centre, Ahmedabad, 1992. 17, Banoyjoe, LK. Shastiy, A. 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ACKNOWLEDGEMENTS, We thank Dr Valeie Sheehan, World Resoures Institute for permission o use tuble 114 (p. 256 of World Resourees 1996-97, Mangrove Fxtent and Loss ~ selected countries) vide letter dated 20 Febmaary 2002 Received 8 January 2002: revise accepted 2 Seperaber 2002 1336 ‘CURRENT SCIENCE, VOL. 83, NO. 11, 10 DECEMBER 20n2