Biodiversity in mangroves
Plants in the mangroves
The mangroves are a plant community developed along the coast with regularly tidal inundation and with high salinity of seawater and in some areas where the wind and sunlight are strong. So, the mangrove plants have to adapt to meet the extreme environment by developing some special organs such as roots, stems, leaves, flowers, and fruits, etc. Cleary, the adaptations of mangrove include the supporting and aeration root that mangrove plants can grow on the soft and anoxic muddy substrates; mangrove leaves have salt glands, are waxy and fleshy, and the stomata (breathing pores) are available in underside of the leaf; the seedlings are rapidly developed when it falls into the water because the seedlings are developed while they are attached to the parent tree, In Thailand, there are various species of mangrove plants which are different by each area. According to the study of The Office of Mangroves Conservation, Department of Marine and Coastal Resource, 78 species of the mangrove plant in Thailand have been reported as shown in Table and Figure
Table A variety of mangrove plants in Thailand
|1||Rhizophora apiculata||35||Phoenix paludosa|
|2||Rhizophora mucronata||36||Ceriops decanadra|
|3||Finlaysonia maritima||37||Ceriops tagal|
|4||Pluchea indica||38||Lumnitzera racemosa|
|5||Dolichandrone spathacea||39||Lumnitzera littorea|
|6||Melastoma villosum||40||Bruguiera hainesii|
|7||Nypa fruticans||41||Bruguiera sexangula|
|8||Barringtonia asiatica||42||Bruguiera gymnorrhiza|
|9||Barringtonia racemosa||43||Thespesia populnea|
|10||Suaeda maritima||44||Thespesia populneoides|
|11||Premna obtusifolia||45||Rapanea porteriana|
|12||Amoora cucullata||46||Cynometra ramiflora|
|13||Allophyllus cobbe||47||Atalantia monophylla|
|14||Scolopia macrophylla||48||Merope angulata|
|15||Xylocarpus rumphii||49||Diospyros areolata|
|16||Xylocarpus granatum||50||Cynometra iripa|
|17||Xylocarpus moluccensis||51||Scaevola taccada|
|18||Excoecaria agallocha||52||Kandelia candel|
|19||Cerbera odollam||53||Ardisia elliptica|
|20||Cerbera manghas||54||Stenochlaena palustris|
|21||Pandanus odoratissimus||55||Sonneratia caseolaris|
|22||Derris trifoliate||56||Sonneratia alba|
|23||Bruguiera cylindrica||57||Sonneratia ovata|
|24||Bruguiera parviflora||58||Sonneratia griffithii|
|25||Caesalpinia crista||59||Aegiceras corniculatum|
|26||Ficus microcarpa||60||Calophyllum inophyllum|
|27||Brownlowia tersa||61||Sapium indicum|
|28||Cassine viburnifolia||62||Dalbergia candenatensis|
|29||Peltophorum pterocarpum||63||Clerodendrum inerme|
|30||Wedlia biflora||64||Scyphiphora hydrophyllacea|
|31||Aegialitis rotundifolia||65||Melaleuca cajuputi|
|32||Acrostichum aureum||66||Avicennia alba|
|33||Acrostichum speciosum||67||Avicennia officinalis|
|34||Hibiscus tiliaceus||68||Avicennia marina|
|69||Terminalia catappa||74||Intsia bijuga|
|70||Heritiera littoralis||75||Flagellaria indica|
|71||Heritiera fomes||76||Acanthus volubilis|
|72||Derris indica||77||Acanthus ebracteatus|
|73||Oncosperma tigillaria||78||Acanthus ilicifolius|
Source: Office of Mangroves Conservation, Department of Marine and Coastal Resources (B.E. 2552)
Examples of mangrove plants in Thailand
Sources: Office of Mangroves Conservation, Department of Marine and Coastal Resources (B.E. 2552)
Animals in mangroves
Not only shrimps, shells, crabs, fish, birds, mammals, reptiles, and insects are found within mangroves, but also all kinds of small species like protozoan, worms, flat worms, and polycheates etc. Those animals can be classified by their living patterns as free living animals, sessile animals, filter feeders, and infauna.
Most of the fish found in the mangroves are abundant and important in terms of the economy including Milkfish and Silver Perch. Type and abundance of fish are varied by seasons, currents, salinity and temperature of seawater, types and numbers of predators. Fish in the mangroves can be categorized as four groups: resident fish, temporary fish, and seasonal fish.
There are approximately 15 types of shrimp found in mangroves; the ones which are economically important include tiger prawn and banana shrimp. Besides, some species spawn their eggs at the mangrove with brackish water including giant freshwater prawn and other freshwater prawns.
Mollusks found in the mangroves include bivalves like oyster, cockle and other bivalves, that may live in the substrate or attach to the stems, root, branch, and leaves of mangrove plants, while shipworms lives within the dead truck or submerged woods. In addition, the gastropods genus Cerithidea are also found in mangrove.
About thirty kinds of crab found in the mangroves, the famous ones are a meder's mangrove crab and fiddler crab, both of which are colorful, whereas, giant mud crabs are usually caught as a human food.
Birds found around the mangroves consist of resident birds and migratory birds. The resident birds inhabit and build their nests in the mangrove area include little egrets, little cormorants, red-backed sea eagles, whereas, migratory birds seasonally fly from other areas through the same route along the continents to the mangroves in order to halt and rest because the mangroves provide their food sources as well as the shelters from storms and their predators. The migratory birds include giant birds, spoon-billed sandpipers, seagulls, etc.
Except the aquatic animals, other animals can be found in mangroves including bats, monkeys, rats, wild cats, fishing cats, wild pigs, and barking deer. These animals come to the mangroves when they want to find some food.
Examples of organisms in the mangrove of Thailand
Scientists expected that fungi had developed from the algae which are able to photosynthesize. Each group of fungi had evolved from the different group of algae. Currently, it is found that terrestrial fungi are more developed than aquatic fungi. With the passing of time, some fungi had adapted, developed, and moved back to grow in marine environment recognized as marine fungi. Fungi found in mangroves are called Manglicolous fungi consisting of higher fungi in the sub-division Basidiomycotina for 20%, while, 80 % of them are lower fungi in the subdivision Ascomycotina and Dueteromycotina. In mangroves, marine fungi are found on various materials such as branches, leaves, submerged roots, including sediment and in brackish water. They are the important organisms in decomposition process of marine and coastal environments.
There are about 200 species of higher fungi found in mangroves all over the world and more species are going to be explored the future. Most fungi are in the Sub-division Basidiomycotina that can produce filaments. In addition, true marine fungi can also be found with colorful spores, filaments, and the mucus are produced in order to help them attach with natural substrates and enhance successfulness of their reproduction. Some fungi are grown only with on the specific plants such as Halocyphina villosa which is usually found on the stems of Avicennia alba but rarely found on the stems of Bruguiera cylindrical and Rhizophora apiculata, whereas Coronopapilla mangrovei generally found on genus Xylocarpus. Some species of fungi, for examples the genus Phellinus, are only pathogenic to Xylocarpus granatum that cause stem rot.
However, in Thailand, the research regarding marine fungi, halofungi, and other fungi in the mangroves in this region are rare. Most researches on marine fungi have been conducted in India covering the symbiosis relationship between fungi and mangrove plants. Besides, some resources have also been studied in Hong Kong, Singapore, and Malaysia. In the last three or four years, it was reported by National Center for Genetic Engineering and Biotechnology (BIOTEC) that more than 160 species of marine fungi were found in Thailand and approximately 1,400 strains of them have already been collected at BIOTEC. Whiles, the study of other mangrove fungi, especially, on the genus Phellinus are still rare. According to Aniwat and Theerawat (B.E. 2533), 59 species of marine fungi were found and 50 species of them were in Sub-division Ascomycotina. They also suggested for future research that the number of sampling station should be increased.