Sri Lanka has a striking variety of forest types brought about by spatial variations in rainfall, altitude and soil. The forests have been categorized broadly as tropical wet lowland evergreen forests (at elevations between 0-1000 m); wet sub-montane forests (at elevations between 1000-1500 m in the wet zone); wet montane forests (at elevations of 1500-2500m); tropical dry mixed evergreen forests in the dry lowlands, with riverine vegetation along river banks; tropical moist evergreen forest in the intermediate zone; thorny scrub in the arid areas; and mangrove swamps in the coastal areas, fringing the lagoons and at the river mouths. In addition, different types of grasslands occur in the wet and dry areas, in the lowlands as well as in the hills. As the wet lowland forests transform into sub-montane and montane forests, there is a progressive decline in canopy height, and at the highest elevations above 2000 m, unique pygmy forests may occur. The most extensive forest type, the tropical dry mixed evergreen forest, is characterized by a canopy that is relatively open and seldom exceeds 20 meters in height.
Forest Types Found Within the Island of Sri Lanka
|Forest Classification||Characteristics (Annual Avg.)||Approximate Extent (Sq. km) On Island||Districts Containing Forest Type *|
|Montane Forest||Above 1500 m elevation Temperatures ~ 15 ° C Rainfall > 1800 mm with no moisture deficit period||31||Nuwera Eliya, Kandy, Badulla, Matale, Ratnapura|
|Sub-Montane Forest||Within elevations of 1000 m to 1500 Temperatures 15 ° – 20 ° C Rainfall > 1800 mm||690||Nuwera Eliya, Ratnapura, Kandy, Matale, Badulla, Kegalle, Matara, Anuradhapura, Monaragala|
|Lowland Rain Forest||Extending from the Coastal plains to 1000 m Temperatures > 20 ° C Rainfall > 2500 mm no moisture deficit period Vegetation –visible lichen and liana species||1415||Ratnapura, Kalutara, Galle, Matara, Kandy, Matale, Kegalle, Nuwera Eliya, Colombo, Badulla, Monaragala, Gampaha|
|Moist Monsoon Forest||Found at < 1000 m Rainfall 1800 – 2500 mm with a peak from October – January with a dry period of 3 months following.||2439||Monaragala, Polonnaruwa, Ampara, Matale, Badulla, Batticaloa, Ratnapura, Kandy, Nuwera Eliya, Matara, Kurunagala, Hambantota, Gampaha, Trincomalee|
|Dry Monsoon Forest||Has a distinct season: a rainfall peak from mid October to January (coinciding with monsoon rains) and a dry period for 3-6 months. Vegetation is semi diciduouse. At elevations of < 600 m often on slopes. |
Rainfall 1000 – 1800 mm
|10940||Anuradhapura, Mullaitivu, Monaragala, Mannar, Trincomalee, Vavuniya, Puttalam, Ampara, Polonnaruwa, Killinochchi, Battocaloa, Hambantota, Matale, Kurunagala, Ratnapura, Badulla, Jaffna, Matara|
|Riverine Dry Forest||Found along flood plains and river valleys. < 600 m Rainfall 1000 – 1800 mm||224||Ampara, Monaragala, Hambantota, Trincomalee, Puttalam, Mannar, Polonnaruwa|
|Mangrove Forest||Present along intertidal sheltered coastlines, usually associated with river mouths and lagoons. Vegetation usually consisting of Rhyzophora species||87||Puttalam, Trincomalee, Batticaloa, Mannar, Hambantota, Mullaitivu, Killinochchi, Ampara, Jaffna, Galle, Gampaha, Kalutara, Matara|
Forest and related ecosystems in Sri Lanka
|Ecosystem Type||Extend (ha)|
|Tropical wet lowland evergreen forest (includes lowland and mid elevation rain forests)||123302|
|Tropical sub-montane forest||28513|
|Tropical montane forest||44758|
|Tropical moist monsoon forest||117885|
|Tropical dry monsoon (mixed evergreen) forest||1121392|
|Tropical thorn forest||NA|
|Riverine dry forest||2425|
|Grasslands (wet pathana, dry pathana, savannah, etc)||68043 (savannah only)|
Natural Forest Cover by District in Sri Lanka -1999
|DISTRICT||Land Area (ha)||Montane Forest||Sub Montane Forest||Lowland Rain Forest||Moist Monsoon Forest||Dry Monsoon Forest||Riverine Dry Forest||Mangrove||Sparse Forest||Total|
Tropical wet lowland evergreen forest
The southwest region and the central hills of Sri Lanka have the most luxuriant forest cover. They have rain during the southwest monsoon and constitutes the lowland rain forests up to an elevation about 900 meters. At higher elevations they change to montane rain forests. Both these are very similar to those of India’s Western Ghats.
These forests are characterized by the dense canopy of tree species reaching 30-40 m in height with the emergent rising 45m above the canopy layer. Unlike the other forest types in Sri Lanka, rainforest are characterized by 5 main canopy layers as Emergent layer, Canopy, Mid canopy, Understory and Forest floor. Woody lianas form an intricate network inside the forest area. Trees bears some unique features as rainforest tree species show greater adaptation for long lasting rain falls, the leaves are even and have drip tips that allows excess water to fall off from the leaf surface. Trees are green throughout the year and since there aren’t any significant climatic variations within a year, trees continue to grow all round the year without shedding leaves at a specific time. Root systems of the plants are shallow because majority of the nutrients are present on the surface of the ground soil layer. Many roots become buttress stems to support these trees and prevent them from falling due to the shallow root system. These forests have a relatively sparse undergrowth but are rich in epiphytes and lianas. Epiphytes are those plants that hang on to a big tree, which is its host. It takes its food from the air. On the other hand, a parasite takes its food from the host plant itself. The interior of these forests are dark and dense. They have an understory made of small trees and shrubs and the ground layer consisting of herbs.
Sri Lanka’s lowland rainforests covering 2.1% of the land area harbour many endemic and threatened species. More than 60% of the 306 tree species that are endemic to Sri Lanka are found only in the lowland rainforests and some more are shared with montane and dry zone forests. Of the twelve endemic genera of flora of the island, eleven are confined to rainforests. The best known tropical rainforest in Sri Lanka is Sinharaja, internationally recognized as a world heritage site.
Kaneliya, Dedugala, Nakiyadeniya complex known as the KDN forest, Bambarabotuwa, Morapitiya Runakanda, Gilimale and Eratne are some of the other reserves. The diverse vegetation of Sinharaja provides habitats to a wide array of fauna. Thiniya, (Shorea congestifolia) Duna (Shorea stipularis), Duna (Shorea zeylanica) are some of the emergents found in Sinharaja. Hora (Dipterocarpus zeylanicus), Honda Beraliya, (Shorea megistophylla)and Batu Naa (Mesua nagasarium)are some of the species that make the canopy. Thapassara bulath (Apama siliquosa) beru (Agrostistachys spp), Galkaranda (Humboldtia spp) are commonly found in the sub canopy. Herbs like Goniva (Acrotrema) Sandaraja (Anoectochilus setaceus), Lianas such as Calamus – Rattan palms, Entada pusaetha – Pus wel (Entada pusaetha), Coscinium – veniwel contribute to the variety of the forest.
The vertebrate animals of Sinharaja consists of about 50% of native inland animals of which 30% are endemic. Mammals like the Leopard (Panthera pardus), Purple faced Leaf Monkey (Semnopithecus vetulus)(endemic), Black naped Hare (Lepus nigricollus), Fishing Cat (Prionailurus Viverrinus) and Rusty Spotted Cat (Prionarilurus rubiginosus) are found together with numerous amphibian and reptile species. The vegetation dwelling tree frogs (Genus Philautus), who lay eggs in crevices and leaves and hatch out as tiny adults, are commonly found. All rainforests such as Sinharaja are famous for the colurful array of bird life. Sinharaja has four endemics the Blue Magpie (Cissa oronata), Green billed Coucal (Centrophus chlororhynchus), Sri Lanka Spurfowl (Galloperdix bicalcarta) and Sri Lanka Jungle Fowl (Gallus lafayetti). Mixed foraging bird flocks, that is a group of different bird species of birds moving together through the forest, is something that should not be missed. A mixed flock consists of an average of 40 individuals from more than 12 species.
When observing the climate of the rainforests, it does provide the ideal conditions for tropical evergreen forest tree species. An average temperature is approximately 23.6’C and annually receives more than 2500mm rainfall to the forest lands during the binaural monsoons. Most of the soil groups that can be found from rainforest is Red Yellow Podzolic Soils with clearly distinguishable horizons that vary with the soil depth. Little accumulation of Organic matter can be observed in the soil. Rainforest soil is a poor nutrient pool as many of the nutrients are attracted to the plant which has a greater demand for faster growth.
Tropical sub-montane forest
These are the forests that occur in between the lowland and montane (mountainous) zone , i.e. between 1000m- 1500m altitude essentially transitional being intermediate between rain forests and montane forests. Knuckels range, Peak wilderness, Hatton, Kotagala, Upper slopes of Sinharaja and Deniyaya, Sooriyakanda forests are examples. Theses also are rich in species composition .The endemism is about 50%. The dominant trees are Dun, Keena (Callophyllum spp), Sysygium spp, Malaboda.
The submontane forests in the central massif are dominated by a Shorea-Calophyllum-Syzygium community with a canopy of Shorea gardneri, S. trapezifolia, Palaquium spp., Homalium zelanicum, Calophyllum calaba, C. tomentosum, C. pulcherrimum, Syzygium spp., Cullenia spp., Myristica dactyloides, Cryptocarya wightiana, and Neolitsea involucrata.
Tropical montane forest
The tropical montane forests of Sri Lanka occur above 1500 m in the Central Highlands and Knuckles mountains, but their best development can be seen above 1800 m, and crown the highest mountains and plateaus of Sri Lanka. There is a marked difference in floristic composition and physiognomy against the sub montane forests of middle elevation. They are also known as cloud forests. The largest single expanse occurs as a crescent extending from Siripada to Pidurutalagala (across the Nuwara, Eliya and Horton plains). Pidurutalagala is the highest peak on the island measuring 2524 m and this is still below the timberline for these forests, and there is no upper conifer zone. Isolated patches can also be found on Knuckles, Namunukula and Haputale.
The hot air of the lowlands rise during the morning hours and condense creating huge clouds, which become so heavy that they result in afternoon rains. They cover a total of 1.1% of our land area. At lower elevations, the cloud forests give way to a variety of vegetation, consisting of both temperate and tropical plants, and grassland savannas. Floristically they are less rich than the forests of lower altitudes, but about 50% of all their species are endemic to Sri Lanka. Their structure is also less complex with all trees more or less arranged in a single layer. Their canopies normally reach heights of about 30 feet but on rare occasions extreme dwarf varieties of these jungles occur reaching no higher than about 3 feet. These so-called pygmy rain forests can be found, for example, on Knuckles Wilderness. Another unusual feature is the lack of conifers and members of the Fagaceae, which normally play an important role in the montane forests of Southeast Asia. Conifers, in particular, often form important emergents, but on Sri Lanka this role is mainly played by endemic species of Calophyllum (Hypericaceae). The frequency of various species of Symplocos (Symplocaceae) is a further peculiarity with all but one of them endemic. The tree layer typically comprises Acronychia pedunculata, Actinodaphne ambigua, Adinandra lasiopetala, Aporosa latifolia, Elaeocarpus montanus, Euonymus rovolutus, Gordonia zeylanica, Litsea ovalifolia, Michelia nilagirica, Microtropis ramiflora, Neolitsea fuscata, Olea polygama, Photinia notoniana, Plectronia montana, Pygeum wightianum, Rhamnus arnottianus, Scolopia crenata, Syzygium revolutum, Symplocos spicata and Terstroemia japonica.
While among the many endemic species are Calophyllum walkeri (Hypericaceae), Cinnamomum litsaefolism, Litsea iteodaphne (Lauraceae), Syzygium rotundifolium and S. umbrosum (Myrtaceae). Epyphytes continue to be a major element with many orchids such as Cirrhopetalum odoratissima, Coelogyne odoratissima, Dendrobium aureum, Eria bicolor, Oberonia wightiana and the endemic Ipsea speciosa (Orchidaceae) covering the branches of trees. Mosses and filmy ferns cover many of the tree trunks and lichens hang from twigs. However, there are fewer climbers, but species such as Asparagus falcatus, Elaeagnus latifolia and Toddalia asiatica are often prominent. On the Knuckles range there are a number of rare, endemic species associated with these forests such as Calophyllum trapezifolium (Hypericaceae), Eugenia lucida, E. phylliroides (Myrtaceae) and Stemonoporus affinis (Dipterocarpaceae) that are confined to these mountains. In general the field layer is often densely carpeted with Webera montana, species of Stenosiphonium and dwarf bamboos such as Indocalamus wightianus, Oxytenanthera monodelpha and Teinstachyum attenuatum. Other associated species include Diacalpe aspidioides, Doodia dives Lastraea beddomii, Leptgramme totta, Lomaria patersoni, Muranta fraxinae and Osmunda javonica.
These forests provide an ideal habitat for many animals including many mammals Leopard (Panthers pardus), Wild Boar (Sus scorfa), Barking Deer (Muntiacus muntjak), Loris (Loris tardigardus) the smaller cats, the Purple faced Leaf Monkey, Porcupine (Hystrix indica) and Golden Palm Civet (Paradoxurus zeylonensis). New species of frogs, lizards, fish and crabs are still being discovered here. One of the smallest terrestrial mammals in Sri Lanka, Kelaart’s Long-clawed Shrew (Feroculus feroculus), is found only in the mountains of this eco region while the endemic Pigmy Lizard (Cophotis ceylanica) is found only in cloud and montane forests above 1300 m.
Elephants once roamed in Sri Lanka’s Cloud forests, where they formed tunnel-shaped paths through the undergrowth of mainly Strobilanthes spp. (Sinhala – Nillu). Only a few are left now on the Rakwana side of this forest.
These high altitude forests are the source of almost all Sri Lanka’s major rivers. The protection of these forests, which are catchments, will ensure that the rivers have water right throughout the year especially during the dry weather. A catchment is where the rainwater is absorbed into the soil and released steadily throughout the year.
Tropical moist monsoon forest
These forests are located in the transition zone or between the tropical rain forests and dry mixed evergreen forests. They bear similarities in species composition to both the tropical lowland wet evergreen forests and the tropical dry mixed evergreen forests and some species of their own. Fragments of this forest type are seen at Barigoda near Kurunegala and Daragoda near Moneragala, and more extensive areas in Randenigala and Samanalawewa. The dominant families here are Anacardiaceae, Sapindaceae, Euphorbiaceae and Moraceae. The dominant species are Mangifera zeylanica, Canarium zeylanicum, Filicium decipiens, Dimorcarpus longan, Nothopegia beddomei and Gironniera parvifolia. Lianas are abundant in this forest type. Only about 17 % of the tree species in them are endemic to Sri Lanka. One of these endemics is Hopea brevipetiolaris on the crest of Doluwakanda, which is its only habitat.
Tropical dry monsoon (mixed evergreen) forest
Dry mixed evergreen forests are the most extensive type of forests and are found in the dry zone. They are characterized by monsoon forests and thorn scrub lands. Evergreen forests represent the tropical dry forests covering a major part of the dry zone adding up to 16.8% of the land area except for the southwestern quarter, the central mountain range, and the Jaffna Peninsula in the extreme north. Dry mixed evergreens receive about 1,500-2,000 mm of annual rainfall in December to March northeast monsoon period but are mostly dry during the rest of the year. The strong seasonality in rainfall has prompted these forests to be referred to as monsoonal forests.
Topographically, the ecoregion is flat, except for scattered inselbergs. Inselbergs are rocky outcrops in a flat landscape. The evergreen dry forests have no canopy formation and trees seldom exceed 20m in height. Although deciduous species exist in these forests their evergreen character is maintained by a few widespread species. Deciduous is where the leaves fall off periodically and grow again. These forests are dominated by Palu (Manilkara hexandra) (Sinhala – Palu), Satin (Chloroxylon sweitenia) (Sinhala – Burutha), Drypetes sepiaria, Feronia limonia, Vitex altissima, Syzygium spp., Drypetes sepiaria and Chukrasia tabularis.
The scrub and regenerating forests are characterized by Bauhinia racemosa, Pterospermum suberifolium, Cassia fistula and Dichrostachys cineria. Acacia thorn scrub grows in disturbed areas. Ritigala, the isolated hill in central Sri Lanka, is a hotspot of endemic species within this ecoregion with several endemic plants such as Madhuca clavata.
The appearance of these forests differs seasonally and depicts an annual cyclical variation in floristic diversity of the ground vegetation. Leaves of plant species here are small, without drip tips; many have compound leaves. The tree trunks branch lower down and show no buttresses, compared with those in rainforests. Epiphytes and lianas are relatively sparse in this forest type. A significant proportion of this flora is similar to that of India, and only about 13 % of the tree species are endemic to Sri Lanka. These forests are rich in quality hardwood species suitable for sawn timber and for this reason and for agricultural expansion, they have been clear-felled in the past and are now mostly restricted to protected areas.
Compared with Sri Lanka’s rain forests, these forests do not have very high levels of endemism. Nevertheless, they harbour one of Asia’s largest elephant populations, estimated at 3,500 to 4,000 animals and many large mammals. Several of the ecoregion’s mammals are also listed as threatened; elephant (Elephas maximus), the Sri Lankan leopard, the vulnerable Sloth Bear (Melursus ursinus), Purple-faced Leaf Monkey and Slender Loris. The richness of bird life is greater, with 270 species, which include several endemic species namely Red-faced Malkoha (Phaenicophaeus pyrrhocephalus), Ceylon Spur Fowl, Jungle Fowl, Brown-capped Babbler (Pelleorneum fuscocapillum) and Ceylon Hanging Parrot or Ceylon Lorikeet (Loriculus beryllinus).
Tropical thorn forest
This ecosystem is found in the arid zone that is northwest and southeast of the island. Temperatures are very high over 34 o C, and prolong drought period from May to September, the rainfall is below 1250 mm annually. The vegetation is a low open thorny scrub with isolated patches of trees.
The common species in these types of forests are: Heen Karamba (Carissa spirarium), Eraminiya (Zizyphus), Maha Andara (Acacia leucopholea and Acacia planiformis), Andara (Dicrostachys cinera), The isolated patches of trees comprise mainly of Maliththan (Salvador persica) and Palu (Manilkara hexandra). Endemic plant species are almost absent in these forests. In Yala and Bundala, this ecosystem together with its neighbouring grasslands and water bodies, harbour large mammals (leopard, elephants, spotted deer, sambhur and wild pig, primates etc.), numerous water-and inland bird species (both migrant and resident) reptiles, amphibians and a diversity of invertebrate species.
Riverine dry forest
These are forest associated with rivers and their flood plains. An interesting marsh forest is the Waturana forest, (12 ha) located in Kalu ganga basin. Two endemic plants are present Mesua stylosa and Stemonoporus moonii. Mahaweli ganga associated riverine forest dry zone is very rich in biodiversity and highly productive. All dry zone rivers form an important habitat for wild life especially large grazing animals like elephants, deer and buffalo.
Grasslands (wet pathana, dry pathana, savannah, etc)
Very broadly, based on elevation, climate, plant composition and degree of disturbance, six types of grassland ecosystems are recognized in Sri Lanka. They are the following: The wet patana grasslands, found around and above 1800 m altitude, are best seen in Horton Plains and around Nuwara Eliya. They are dominated by the tussock grass species Chrysopogon nodulibarbis and Arundinella villosa on higher ground and Garnotia exaristata and the dwarf bamboo, Sinarundinaria densifolia, close to waterways. A diversity of delicate, small herbaceous species with colourful flowers grow among the grasses. They include Pedicularis zeylanica, Satyrium nepalense, Exacum walkeri, Osbeckia spp., Ranunculus spp. (some very seasonal) and the fern Pteridium revolutum. Rhododendron arboreum ssp. zeylanica about 2 m tall, often displaying spectacular brilliant red flowers, the shorter Gaultheria leschenaultia whose leaves smell of wintergreen and the invasive spiny Ulex europaeus, are the widely scattered woody species in these grasslands.
During less wet periods of the year, February to April, these grasslands are subject to accidental fires. These fires, ground frost in January/February, a high water table and herbivory all contribute to the maintenance of these grasslands.
In the early 1960s about 120 ha of wet patina grassland were used for cultivation of seed potato by the Department of Agriculture and later abandoned, following which the area was gradually converted to a carpet-like grassland dominated by the exotic Penesetum sp. This grassland, with its vegetation growing close to the ground, does not provide environmental conditions and microhabitats for the herbaceous flora to thrive, unlike among the tussock grasses of the natural wet patana. Therefore, its floristic richness is much less, and consequently its faunal diversity as well.
Sambhur, wild boar and black-naped hare feed in these grasslands at night but rest in the adjacent forests during the day. The grassland/forest complex provides them an ideal system for survival. Among the other animals recorded are three endemic freshwater crabs (Ceylonthelphusa scansor, Perbrinckia punctata, P. glabra), the endemic shrimp (Lancaris sinhalensis) and among the amphibians Philautus microtympanum, Fejervaryia greenii, Microhyla zeylanica and Polypedates eques inhabit the streams and/or their immediate environs.
Among the wet patana grasslands, the flora and fauna has been best studied in Horton Plains. The dry patana grasslands, located between 500 – 1000 m elevation, are relatively widespread, occurring in the Uva basin, and around Gampola, Nawalapitiya, Hantana and Rakwana. These grasslands have resulted from the removal of tree vegetation for agriculture and subsequent abandonment. The dominant grass species in them are Cymbopogon nardus and Themeda tremula, both forming tussocks. Other species seen among the grasses include a large number of tall composite herbs (Blumea spp., Vernonia spp. etc.) and semi-woody to woody shrubs (Cassia spp., Crotalaria spp., Lantana camara, Osbeckia octandra, Psidium guajava, Wikstroemia indica).
During the dry months these dry patanas are purposely burnt to obtain fresh grass for fodder or to hunt animals. Their very existence is a result of fire. Much of these grasslands are now converted to agricultural land and Pinus and Eucalyptus plantations. They are also being taken over by the aggressively competitive exotic fodder grass Panicum maximum and invasive species like Clusia rosea. Ecology of the vegetation in the dry patana grasslands has been studied at Hantana.
The savannas occur in the intermediate and dry zones, between 300–1000 m elevation. Those on the eastern slopes of the central massif and around the Uva basin are called upland savannas while those in Moneragala and Bibile and in the Gal Oya basin are known as lowland savannas. They resemble a parkland, with scattered, fire-tolerant trees dominated by Careya arborea, Phyllanthus emblica, Terminalia chebula, T. bellirica, all with medicinal properties. The ground layer is dominated by the grass species Cymbopogon polyneuros in association with Themeda triandra at higher elevations and Aristida setacea and Panicum sp. at the lower elevations. Savannas are maintained by anthropogenic fires, mostly to facilitate the collection of fallen fruits of the medicinal species. These savannas are used as foraging habitats by elephants and other herbivores, especially when there is new growth of the grass species after they have been set on fire.
Damanas, also known as dry low country parklands or grasslands, occur in the Ampara and Batticoloa districts of the eastern dry zone. They are dominated by the tussock grass Cymbopogon nardus. Other less abundant grass species include Aristida setacea, Imperata cylindrica, Themeda spp., Brachiaria spp., Cyanodon dactylon, Echinocloa colona, Eragrostis sp. and Sporobolus diander. Scattered in the grass are herbaceous (Alisicarpus vaginalis, Desmodium heterophyllum, D. triflorum), woody shrubs (Calotropis gigantea, Cassia auriculata, Lantana camara) and trees (Manilkara hexandra, Pterocarpus marsupium, Acacia leucophloea, Butea monosperma). Damanas provide fodder to wild elephants and buffaloes. Indeed, these animals are largely responsible for the maintenance of this vegetation, which except for their impact, is likely to contain a higher density of woody species. Leaves of Diospyros melanoxylon, locally known as Kadumberiya, growing in this ecosystem are widely used as wrappers for local cigarettes (beedi).
Talawa grasslands occur in the Haldumulla area, where the topsoil is eroded and truncated to some degree. While the tall (1.5 m) tussock grass Cymbopogon nardus dominates them, other less abundant grasses seen are Andropogon lividus, Arundinella villosa, Chrysopogon aciculatus and Themeda tremula. The herbs and shrubs scattered among the grass include Desmodium triflorum, Elephantopus scaber, Evolvulus alsinoides, Lantana camara and Psidium guava.
A mangrove is a swampy area found in the costal areas and at river mouths. They are periodically inundated by sea water. Rich mangrove forests exist in the Puttlam and Kalpitiya areas, and Portugal and Dutch bays. Dense strips of mangroves also occur in the southwest and southern coasts. The total mangrove area in the island is estimated between 6,000 -13,000 ha. Fourteen mangroves species and 12 associated species have been recorded. Mangrove trees have many adaptations to survive in water logged, saline soil with very little areartion. Stilt and prop roots for support, pneumatopores, which are roots for breathing air and which stick out of the water to take in air, salt and to relieve excess salt are such adaptations. There are many types of fauna of which some are adapted to this specific environment. Mud skipper; a fish who enjoys a walk, the Fiddler crab with one big claw, are some. Some mangrove trees exhibit viviparity; that is the seed germinates while attached to the mother plant. This longer period of development before release, ensures the survival of the plant.
Mangroves are essential for nutrient retention for certain species of fish and shrimp to breed. However mangroves are being destroyed for the expansion of human settlement and for aquaculture. Poles, firewood, twigs for brush piles etc. are extracted from mangroves. Pollution and siltation affects the quality of the trees Thus we find that the mangroves are fragmented exploited and degraded.