Vol. 5(8), pp. 446-454, August 2013

DOI: 10.5897/IJBC12.004

ISSN 2141-243X © 2013 Academic Journals

http://www.academicjournals.org/IJBC

International Journal of Biodiversity and Conservation

Review

Mangrove forests of river estuaries of Odisha, India

Sitaram Prasad Panda1*, Hatanath Subudhi2 and Hemant Kumar Patra3

1Regional Plant Resource Centre, Ekamrakanan, Nayapalli, Bhubaneswar-15, Odisha, India.

2Crop Improvement Division, Central Rice Research Institute, Cuttack, Odisha, India.

3Post Graduate Department of Botany, Utkal University, Vani Vihar, Bhubaneswar, Odisha, India.

Accepted 11 June, 2013

A clear and current picture of the mangrove forests extant in different river estuaries of the Odisha state of the Indian sub-continent have been provided in this communication. Apart from their role in upgrading the state’s economy, the other features exploited by the local inhabitants have been highlighted in brief. Effective measures for the conservation of these rare and unique ecosystems have also been suggested. Key words: Mangroves, river estuaries, conservation.

INTRODUCTION Odisha, one of the coastal states of India lying between 17° 48’-22° 94’N latitude and 81°24’ - 87°29’ E longitude has a coastline of 480 km stretching over districts like Balasore, Bhadrak, Jagatsinghpur, Kendrapara, Puri and Ganjam. It extends over an area of 155,707 sq.km accounting for about 4.87% of the total area of India. The coastal areas are interrupted by several rivers and rivulets, the Mahanadi, Brahmani, Baitarani, Budhabalanga, Rusikulya and Subarnarekha (Figure 1). Chilika, the largest brackish water lake located in the east coast, deserves special mention. All are mixed with the Bay of Bengal forming deltas, which have thick mangrove forests. Among those, the tidal and littoral swamp forests deserve special mention, being one of the conspicuous and important forest types of the Odisha coast. The tidal and littoral swamp forests extend from Chandipur coasts in Balasore district to Gopalpur of Ganjam district, either as a continuous belt or in scattered patches along the creeks and channels of estuaries including fringes of the Chilika. The major mangrove forests of Odisha are mainly confined to two places namely Kanika and Kujang, the ex-Zamindari areas of the un-divided Cuttack district, the former being situated along the river Dhamra (Bhitarkanika Wildlife Sanctuary, Figure 2) and the latter in the Mahanadi delta. Littoral scrub jungles with some specific

plants characteristic of deltaic swamps are distributed near Chandipur, Astaranga, Gopalpur, rocky faces of Chilika Lake (Figure 3) and a few other localities. As compared to the total of 76,500 sq.km forest cover in Odisha, an area of about 195 sq.km is under mangrove forest (mangals) according to the Remote Sensing Agency report, Dehra Dun in 1991, which is quite insignificant. The mangroves of Odisha are the second largest mangal formation of the country after the Sunderbans of India in both area and in respect of species composition. Unlike the other states of India, the coastal belt of Odisha has experienced severe vegeta-tional devastations leading to rapid shrinkage of many rare and endangered plant communities like mangroves. Due to such devastations, the coastal belt has faced severe oceanic cyclones with high wind velocity which costs many lives. The shrinkage of mangroves population of the coast is mainly due to biotic as well as abiotic interference.

Due to therapeutic as well as other uses, plants have been over-exploited ruthlessly. Again, due to the opera-tion of biotic factors such as human population explosion, and the spread of urbanization and industrialization, the plant wealth has been destroyed.

In view of these facts, the exploration of the wealth of *Corresponding author. E-mail: situ.1979@gmail.com. Tel: +91 9776190014.

Panda et al. 447

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Figure 1. Major river system of Odishawith their estuaries and distribution of mangroves.

448 Int. J. Biodivers. Conserv.

Figure 2. Map of Bhitarkania Sanctuary.

Figure 3. Map of Chilika Lake.

plant species, its documentation, conservation and proper utilization, is vitally important.

The coastal zone including the mangroves and associated vegetation types have been severely affected by the felling of trees for fuels and timbers, the spread of urbanization, industrialization, aquaculture of prawns, and settlement of refugees. The mangrove vegetation parti-cularly on the coast of Odisha (the Mahanadi delta, Devi estuary, Rusikulya estuary, Subarnarekha estuary, Chilika lagoon, etc.) has been highly denuded due to severe biotic pressure such as human settlement, construction of Paradeep port and Paradeep Phosphate factories, prawn culturing and nowadays only the remnants of the past vegetation in the form of shrubby elements are seen. REVIEW OF LITERATURE In the past, Odisha had very rich and diverse vegetation in general and mangroves in particular owing to its pecu-liar geographic location coupled with various edaphic factors. However, these rich flora were not explored till the botanical work of Haines (1921), the pioneer plant explorer for Bihar and Odisha. From his treatise “The Botany of Bihar and Orissa” it was found that a majority of the plants he collected were from Bihar state and only a few from Odisha. Being aware of these facts, the sub-sequent worker, Mooney (1950) collected plants mostly from Western Odisha, Mahanadi delta and mentioned it in his treatise “Supplement to the Botany of Bihar and Orissa”. Thus it is evident that information on the flora and vegetation of this area are very meagre.

Out of the 32 forest types, littoral and tidal swamp forests are very conspicuous and worth mentioning for the state of Odisha (Champion and Seth, 1968). The mangrove forests occur in discontinuous patches in the districts of Balasore, Bhadrak, Ganjam, Jagatsinghpur, Kendrapara, Puri and in the fringes of the Chilika lagoon. Haines (1921), has reported 37 species under 30 genera belonging to 23 families from Mahanadi delta and Chilika lake without mentioning the precise locality. He briefly discussed the mangrove formation under the heading “Coastal tract” (in which he mentioned some mangrove species and their associates. He has provided general information on the coastal flora in the introductory part of his treatise. Mangroves from the estuaries of Brahmani, Baitarani, Rusikulya and Devi were not studied by Haines, although these regions harboured a rich mangrove flora. Later on realizing this, Narayanswami and Carter (1922) collected plants extensively from Barakuda, Sanakuda and Ghantasila islands of Chilika. Mooney (1949) also made a short trip to Jambu, Hukitola and False point of Mahanadi delta in the month of June 1949. He added 12 species from these regions to his compendium. Out of these, 10 species turned out to be new records for the state of Odisha. Both workers, Haines and Mooney em-phasized that further detailed studies of the unexplored

Panda et al. 449 and under explored coastal belt will add more species to the coastal flora. After these works, no further floristic studies of the Odisha coast in general and mangroves in particular occurred for quite a long time. More recently, Rao and Banerjee (1967, 1982), Rao et al. (1970), Banerjee and Das (1972), Rao and Shastry (1974) and Banerjee (1986) have studied the coastal vegetation of Odisha and made a number of new distributional records for the state of Odisha. After these coastal works, Patnaik (1973) made an ecological study on the aquatic flora of the Chilika lake. Thereafter, Banerjee (1984), Choudhury (1984, 1986, 1987, 1990a, b), Patnaik and Choudhury (1989), Samal and Patnaik (1989), Biswal and Choudhury (1993) and Reddy et al. (2006) carried out floristic surveys of the Bhitarkanika Wildlife Sanctuary especially on the mangrove elements and studied their socio-economic aspects. Misra and Panigrahi (1984) studied the taxo-nomy and distribution of the mangroves of Rhizophoraceae in Odisha. Choudhury et al. (1991) and Choudhury (1994, 1998, 2001) highlighted in detail the diversity and conser-vational aspects of the mangroves of the Bhitarkanika, Paradeep and Mahanadi delta. Later on, Panda et al. (2004, 2005a, b, 2007, 2010), Panda and Patnaik (1998), Panigrahi (1998) and Choudhury et al. (2004) studied various aspects of the general flora as well as the rare mangrove flora of the largest brackish water lagoon, the Chilika and its likely future. Recently Subudhi and Choudhury (1989, 1998), Subudhi et al. (2002, 2006), Nayak and Choudhury (2001), Nayak et al. (2002) and Panda et al. (2004, 2005a, b, 2007) have studied the mangroves of Mahanadi delta and Odisha coast and their conservation as well as utilization. Dhal and Rout (2001) reported a few rare, endangered, vulnerable and threa-tened mangrove elements of Odisha coast and empha-sized the need for immediate conservation.

From this review of the historical literature, it is quite clear that no systematic study of the mangrove flora has been carried out to date. All the workers have focused their attention on the Bhitarkanika Wildlife Sanctuary, the Mahanadi delta and Chilika lake of the Odisha coast. However, attention has not been directed towards the exploration of the existing mangrove vegetation of the other river estuaries like Devi, Budhabalanga, Rushikulya, Subarnarekha, etc., although these regions have a very rich and diverse mangrove flora and play a pivotal role in maintaining the ecological balance of the coast as well as providing protection against environmental hazards. The work done so far emphasizes the need for a detailed floristic and vegetational survey of the coastal belt of the state. Mangrove forests extant in the Mahanadi delta have been experiencing long-term decline. Consequently, the luxuriant forests of yore have been degraded to scrub jungles. The forests extant in other river estuaries of the Odisha coast are also experiencing severe anthropogenic pressure coupled with drastic ecological changes leading to their fast shrinkage. Taking all these facts as well as the multi-facet socio-economic importance of the coastal

450 Int. J. Biodivers. Conserv. flora especially the mangrove forests into consideration, a floristic survey programme in the coastal zone has been undertaken under the auspices of the Post Graduate Department of Botany, Utkal University, Bhubaneswar. Mangrove vegetation of different river estuaries

According to Champion and Seth (1968), the coastal vegetation in Odisha is mainly of littoral and tidal forest types, which are very conspicuous for the state of Odisha.

This is a unique and typical type of vegetation espe-cially found in river deltas, where there is admixture of river water and sea water. In the coastal region of Odisha, estuarine vegetation is commonly found in the river deltas of Budhabalanga, Brahmani, Baitarani, Subarnarekha, Mahanadi and Devi. The vegetation in the river estuary of Brahmani and Baitarani is very rich and abundant due to the enforcement of a wildlife protection act, since the estuary was declared as a sanctuary in 1974. But the vegetation in the Mahanadi delta is denuded due to the construction of Paradeep Port (1965) and the Paradeep Phosphate factory and construction of residential complexes. Many species have been wiped out and some are on the verge of extinction.

In Bhitarkanika, the mangrove formation is seen along the creeks, channels and islets. Generally two-storey system is observed in this mangrove forests since the ground flora is very poor. The dominant mangrove taxa constituting the top canopy are Sonneratia apetala, Avicennia officinalis, Avicennia alba, Excoecaria agallocha, Heritiera fomes (Figure 4), etc. S. apetala and A. officinalis are gregarious and luxuriant, colonising the banks of river and creeks. Xylocarpus granatum is sometimes observed in this habitat (Figure 5). Pongamia pinnata is also found in abundance, usually away from the water bodies. In more elevated areas mixed forest of Excoecaria agallocha and H. fomes are seen in asso-ciation with Phoenix paludosa and Tamarix troupii in the peripheral regions. The second storey is composed of the shrubby elements and under-trees such as Brownlowia tersa, Kandelia candel, Lumnitzera racemosa, Rhizophora mucronata, Ceriops decandra, Cynometra iripa, Clerodendrum inerme, Aegiceras corniculatum and Hibiscus tiliaceus (Figure 6 to 9). These elements flourish where there is tidal influence as well as a high degree of salinity. B. tersa is plentiful along the fringes of water bodies and remains half-submerged in water. Like-wise, R. mucronata trees with their interwoven knee roots are observed in the muddy flats. In the terrestrial and swampy areas Flagellaria indica, Salvadora persica, Phoenix paludosa, Bruguiera gymnorrhyza (Figure 10) etc. are quite common.

Common climbers of this mangrove forest are Derristrifoliata, Derris scandens, Finlaysonia obovata and Mucuna gigantea, etc.

Among the narrow and defuncted creeks usually

Acrosticum aureum (a pteridophytic element), Acanthus ilicifolius are seen in close association. The spiny element Caesalpinia crista is also not uncommon in such localities. The ground flora is rather very poor. Usually in the muddy flats, Myriostachya wightiana is found in pure formation. Porteresia coarctata is also found in patches but less dominant. Other notable herbaceous elements are Suaeda maritima, S. nudiflora, Salicornia brachiata, etc. Tylophora tenuissima, Eugenia bracteata, Fimbristylis spp. etc. are found in more dry and elevated areas.

In the sand dunes and sand bars close to Satavaya and Gahiramatha, the salt bush formation is generally found. Along the littoral tract of Satavaya, Gahiramatha the scattered sand dunes as well as sand bars mostly sustain xeric herbs, of which extensive patches of Ipomoea pes-caprae deserves special mention. Other common xeric elements are Bulbostylis barbata, Cyperus arenarius, Sesuvium portulacastrum and Pedalium murex. These elements act as sand binders as well as sand stabilizers. Soil erosion is considerably checked by the extensive spread of these species. I. pescaprae, Hydrophylax maritima, Canavalia rosea, Cayratia trifolia mostly cover the ground. The herbaceous flora mainly consists of the species like Rothia indica, B. barbata, Launaea sarmentosa, Spinifex littoreus, C. arenarius, Fimbristylis sericea, P. murex, Heliotropium curassavicum, Trianthema portulacastrum, Giseckia pharnaceoides, etc. These species are found gregariously in the sandy areas of the coast. Pure formation of Aegialitis rotundifolia is found near the Ekakula forest rest house of Bhitarkanika Wildlife Sanctuary (Figure 11). I. pes-caprae, an exten-sive creeper is dominant in such habitat. Other herba-ceous elements are H. maritima, L. Sarmentosa, S. portulacastrum, P. murex, C. arenarius, S. littoreus, G. pharnaceoides, etc.

In the Devi estuary, a good patch of mangrove forests is observed. The top canopy consists of A. officinalis, S. apetala, B. gymnorhyza, E. agallocha, K. candel and C. decandra, etc. The second storey consists of shrubby elements like A. corniculatum, A. ilicifolius, Dalbergia spinosa, P. paludosa, T. troupii, H. tiliaceus, C. inerme, etc. In the mud-flats, P. coarctata and M. wightiana are gregarious. The notable climbers are D. scandens, Derris trifoliata and Ipomoea cymosa. Among the sand dunes C. crista, S. littoreus, Solanum trilobatum, I. pes-caprae, S . portulacastrum, E. bracteata etc. are worth mentioning.

In the Paradeep and the neighbourhood of the Mahanadi delta, shrubby elements are gregarious except a few tree species like A. officinalis and S. apetala. The shrubby elements namely A. ilicifolius, E. agallocha, C. crista, D. spinosa, T. troupii, A. corniculatum etc. are commonly seen. Sarcolobus carinatus, D. trifoliata, D. scandens, S. trilobatum, I. cymosa, S. tiliifolia are the notable climbers/twiners of Atharabanki area, where the salinity is comparatively low as the creeks and channels are completely closed due to the pure formation of P. paludosa. So, the sea water does not reach these areas

Figure 4. Heritiera fomes Buch-Ham.

Figure 5. Xylocarpus granatum Koen.

Figure 6.Kandelia candel (L.) Druce.

Panda et al. 451

Figure 7. Rhizophora mucronata Poir.

Figure 8. Ceriops decandra (Griff.) Ding.-Hou.

Figure 9. Aegiceras corniculatum (L.) Blanco.

452 Int. J. Biodivers. Conserv.

Figure 10. Bruguiera gymnorhiza (L.) Lam.

Figure 11. Aegialitis rotundifolia Roxb.

during tide. In Paradeep area, mostly sandy vegetation is quite common. The species namely L. sarmentosa, H. maritima, Capparis brevispina, S. littoreus, C. arenarius, F. sericea, P. murex, Hedyotis umbellata, F. ferruginea, Phyllanthus rotundifolia and R. indica are usually found near the sea coast.

The floristic composition of Hukitola islands, Jambu, Batighar, etc. are different from Paradeep. These regions are dominated by the eumangal and semi-mangal species, there are no sandy communities. Mangroves are the way to Hukitola. The other mangrove forests are encroached by the local people. A. corniculatum, K. candel, E. agallocha, B. tersa, C. decandra and C. tagal are very common along the margins of creeks and channels. Their asso-ciates are I. cymosa, C. inerme, C. crista, etc.

In Jambu, vast areas under mangrove are devastated

for human settlement and piscicultural practices. Man-grove forests are mainly confined to the west side of the Jambu River. The dominant species are A. rotundifolia, C. decandra, C. tagal with Rhizophora species. The other species viz. Azima tetracantha, E. agallocha, A. ilicifolius, Tamarix troupii, C. inerme, D. spinosa, D. trifoliata, D. scandens, H. tiliaceus are found comparatively rarely. On the east side of the river, an extensive area of mangroves has been converted into fallow lands due to human settlement and prawn culture. Near the margin of creeks and channels pure formations of M. wightiana, P. coarctata and C. malaccensis are usually found. These species play a significant role in reducing soil erosion. Similarly, the mangroves of Hetamundia have been converted to grass lands which

provide fodder to buffaloes/cows. Pure formations of Paspalum vaginatum and F. ferruginea were observed in these regions along with some other herbaceous elements. Hukitola island is encircled by water on all sides. So the rate of destruction is very low, which resulted in high species diversity. The dominant ele-ments are A. alba, A. officinalis, C. decandra, K. candel whereas C. tagal, R. apiculata and R. mucronata are very rare near the sea. The common associates are L. racemosa, A. rotundifolia, M. angulata, Premna corymbosa, T. troupii, C. inerme etc. The herbaceous species viz. Synostemon bacciformis, S. maritima, S. nudiflora, Scirpus littoralis, S. brachiata, T. portulacastrum, Alternanthera pyrocnoides are found to occur in the mudflats. Most areas of Hukitola island are planted with Casuarina equisetifolia by the Forest Department. H. tiliaceus, T. populnea, T. troupii are present away from the sea coast.

In the Dhamra estuary, degraded mangrove forests are seen along with some of the associates in small patches. The true mangroves are A. officinalis, C. decandra, S. apetala, which exhibited very stunted growth giving the appearance of small bushy trees. The associates consist of A. ilicifolius, E. agallocha, D. trifoliata, P. paludosa, T. populnea, etc. P. coarctata is usually abundant here, where as M. wightiana is found comparatively in lesser abundance. Both species have a great role in checking soil erosion. The ground flora is very poor. But pure formations of S. portulacastrum and S. maritima are found in the degraded mangrove lands, on semi-dried mudflats.

The Subarnarekha estuary is endowed with a few spe-cies of C. decandra and B. parviflora. Concurrently, A. ilicifolius, E. agallocha, D. trifoliata, etc. are found as associate species. The ground flora and sand dune vegetation are completely absent in this region except some herbaceous species like C. arenarius, C. platystylis and F. ferruginea etc.

The Budhabalanga estuary harbours only the devas-tated as well as degraded mangrove forests, which con-sists of the species like A. officinalis and C. decandra. The shrubby taxa of this area are A. ilicifolius, D. trifoliata,

D. scandens and T. populnea, etc. This region is com-pletely devoid of ground flora and sand dune vegetation.

In the Rusikulya estuary, no significant mangrove formation is observed. Only pure stands of S. maritima are very common. Among the sand dunes, S. littoreus, S. trilobatum, I. pes-caprae are very common.

In the past, the margin of the Chilika lake and the un-disturbed islands like Badokuda, Sanokuda, Ghantasila, etc. were endowed with the unique eco-system of mangroves. But in the course of time, the mangroves have been replaced by tidal scrub jungles and only some mangrove associates are present due to the change of the eco-climatic conditions coupled with the ruthless cutting of trees by the local inhabitants to cater for their various needs. The vegetation is totally devoid of the true mangrove species and only a few associates are encountered in the denuded regions. Such species are S. persica, C. ceylanica, P. pinnata etc. The other species of this category are A. corniculatum, A. tetracantha, Colubrina asiatica, C. inerme, P. aculeata, C. retusa, Meytinus emarginatus, Carissa spinarum, Opuntia stricta, P. suberosa etc. C. quadrangularis, P. capensis, C. roxburghii, C. zeylanica, Tylophora indica, S. acidum, D. trifoliata and M. oblongifolia are quite abundant. The non-mangrove trees of this region are C. adansonii, L. tetraphylla and Streblus asper.

The ground flora is rather very poor and represented by herbaceous elements like C. cretica, I. aspalthoides, S. bacciformis, S. fruticosa, T. triquetra, H. curassavicum, C. prostrata and R. indica. S. trilobatum is very common among the sand dunes. The steep rocks are represented by the matted growth of Dalbergia rubiginosa. Exotic shrubs like Lantana camara var. aculeata, Jatropha gossypifolia, Chromolaena odorata etc. have invaded the vegetation of the rocky lands. Species like S. maritima, S. brachiata, S. portulacastrum, P. nodiflora, H. curassavicum, Diplachne fusca etc. are very common and worthy of mentioning along the edges of the lake. The shifting sands as well as salt laden wind on the

beaches near the lake provide an ideal abode for the growth and development of the psammophytic vegetation in and around the margin of the lake, which is sandy in nature. The broad leaved runners like H. maritima, I. pescaprae, Macrotyloma ciliatum, L. sarmentosa etc. are found abundantly in this region. The herbaceous flora consists of the species like C. arenarius, S. littoreus, B. barbata, Geniosporum tenuiflorum, Hedyotis graminifolia ssp. arenaria, Brachiaria ramosa, Acalypha lanceolata, Bacopa monnieri, Vigna sublobata, Crotalaria nana, Gisekia pharnaceoides, etc. A continuous belt of Pandanus fascicularis is found along the margins of the lake. The common associates of this area are Euphorbia tirucalli, P. capensis, I. obscura and Tinospora cordifolia. Abutilon hirtum and Abelmoschus ficulneus are very common among the shrubs. The land stretching in between the Bay of Bengal and the lake has been planted with Casuarina equisetifolia which is showing luxuriant growth.

Panda et al. 453

This type of Psammophytic and Sand dune vegetation is common and generally found in other areas of the coastal belt of Odisha like Paradeep, Puri-Konark, Devi estuary and Balasore regions.

Hoya parasitica is the only parasitic species of the mangrove forests. Though in Odisha, the mangroves are very rich in species diversity, Nypa fruticans is the only species, which is not found in the deltas of Odisha. It is introduced in the Bhitarkanika National Park from Sundarbans.

CONCLUSION Many species exhibit considerable shrinkage of distribu-tion and are becoming rare and threatened. So, it is high time to conserve these vulnerable/rare/threatened ele-ments before further genetic erosion takes place. Interes-tingly, Cerbera odollam, X. granatum, X. moluccensis, H. littoralis, I. campanulata, S. indicum, A. cucullata, I. bijuga, S. brachiata etc. are present only in Bhitarkanika Wildlife Sanctuary and exhibit very restricted distribution. These are not present in other mangrove forests of Odisha. In the Paradeep terrain, the species like Rourea minor, Finlaysonia obovata, Colubrina asiatica, Taverniera cuneifolia which had been reported earlier could not be located during the present survey. Similarly, the species viz. C. odollam, X. granatum, X. mollucensis, M. gigantea, I. campanulata and I. bijuga abundantly found in Bhitarkanika Wildlife Sanctuary are not found here. In the Bhitarkanika Mangrove Forests, the species like Merope angulata, Sarcolobus carinatus, Sonneratia caseolaris and Acanthus volubilis have shown very restricted distribution and became very rare and vul-nerable which were luxuriantly found in the remote past. H. kanikensis which was reported by the earlier workers from the Bhitarkanika Wildlife Sanctuary, could not be traced during the present survey. The species like C. odollam and X. granatum have shown very tangible shrin-kage of their population putting them in the group of vulnerable and threatened category.

Mangroves prevent oceanic cyclones, soil erosion and sea surges. Due to the destruction of these forest eco-systems in the year 1999, there was severe super cyclone in the entire Odisha coast. So it is high time to conserve the existing mangrove forests and reforestation of the degraded mangrove areas should be taken-up as priority, so that the ecological balance will be maintained. The species like P. coarctata and M. angulata are the wild relatives of rice and citrus, respectively and tolerant to salinity. The salt tolerant gene can be transferred to the rice and citrus through biotechnological methods and these two species should be conserved in situ. Since the mangals need very specific ecological and physiological conditions, ex situ conservation is not possible and the alternative way is the in situ conservation through habitat preservation. This can be achieved only by identifying and declaring selected mangrove rich areas as “Sanctua-

454 Int. J. Biodivers. Conserv. ries”, “Natural Reserves”, “Bio-sphere Reserves”, etc. Concurrently, rehabilitation of mangroves in the denuded area may be attempted, for protection and judicious utili-zation of the economically important mangrove species. Mass awareness may be generated through organization of eco-development camps, workshops, seminars, distri-bution of pamphlets, posters and booklets. Stringent and immediate measures need to be taken to protect and maintain this fast disappearing vegetation.

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