oleh: Melia Novitasari*
Mangroves are plants that grow in tidal areas. The word mangrove can describe a single plant or it can refer to a whole community of plants .They are halophytes (‘salt loving”). Most plants can not survive in salty conditions. The mangrove vegetation is evergreen and simple in physiognomic structure of two to three storeys varying from 5–25m in height, depending on age and localities (MacNae 1968) and Snedaker (1978) (Tomlinson 1986; Ball 1988; Clough 1992; (Chapman 1975); Duke 1992; Smith 1992).
Mangroves grow only in the tropics and subtropics. They do not tolerate cold temperatures well, and freezing temperatures will kill them. Mangroves grow best in sheltered areas with low wave energies. The current estimate of mangrove forests of the world is less than half of what it once was (Spalding et al., 1997; Spiers,1999) and much of what remains is in a degraded condition.
Based on tree dominant species, the mangrove community in Indonesia can be viewed as association (mix stand) and consociation (pure stand). There are five consociations commonly found in Indonesian mangrove, namely, Avicennia, Rhizophora, Sonneratia, Bruguiera and Nypa consociations. Regarding mix stand, association between Bruguiera spp. and Rhizophora spp. are frequently found mainly landward. In general, because of a large variety of local habitat, mangrove communities in Indonesia differ among islands.
All mangrove plants have special adaptations that allow them to survive in their salty environment.Their unusual root systems give them support and stability in the loose soil. There is little oxygen present in these soils and prop roots and pneumatophores allow them to get oxygen from the air. They have live young (viviparous). The seed remains attached to the parents plant until it germinates. It then falls from the tree and drifts on the water until it finds somewhere to take root.
Mangrove forests are among of the most productive and biologically important ecosystems of the world because they provide important and unique ecosystem goods and services to human society and coastal and marine systems. When their leaves fall into the water and are decomposed by bacteria many valuable nutrients are released that are essential to the growth of plankton. Plankton are the producers in this and oceanic ecosystems. Mangrove wetlands provide habitat, feeding, breeding and nursery areas for a wide variety of plants and animals, including endangered species.
Did you know that mangroves can filter out pollutants as like nitrates, phosphates and petroleum based products that are present in run-off? The microbes in the sediment break the pollutants down. The forests help stabilize shorelines and reduce the devastating impact of natural disasters such as tsunamis and hurricanes.
The total area of mangroves in the year 2000 was 137,760 km2 in 118 countries and territories in the tropical and subtropical regions of the world. The largest extent of mangroves is found in Asia (42%) followed by Africa (20%), North and Central America (15%), Oceania (12%) and South America (11%). The mangroves grow in river deltas, lagoons and estuarine complexes (Thom, 1984);
In 2009, the Agency of Survey Coordination and National Mapping (Republic of Indonesia) of Indonesia reported the existing mangrove forest area in Indonesia of about 3,244,018 ha; however, at 2007 the Directorate General of Land Rehabilitation and Social Forestry, Ministry of Forestry (Ditjen RLPS MoF) of Indonesia reported about 7,758,411 ha of mangrove area (including an existing vegetated mangrove area). It was further reported that of those mangroves 30.7% were in good condition, 27.4% moderately destroyed and 41.9% heavily destroyed.
It is reported that while large portions of the mangrove forests have been commercially exploited, the mangrove areas as land resources have been converted to other uses (agriculture, fishery, urbanization, mining and salt ponds) which often raised conflict of interest among users. In some places, over-exploitation and the reclaiming of mangrove areas may result in a degradation and disappearance of mangroves.
In the period of 2010 to 2014, the Ministry of Forestry planned to do mangrove rehabilitation at about 10,000 ha/year through the Mangrove People Nursery (Kebun Bibit Rakyat or KBR) program. In 2013, the target of the mangrove rehabilitation project will be raised up to 15,000 ha through the programs of Land Forest Rehabilitation, People Nursery and Social Aid. Beside the government, many international donor institutions set up joint work to execute mangrove rehabilitation in Indonesia.
So, the conclutions is mangrove conservation in Indonesia work so well. There is cooperate between government and privats. Consequently, the management and utilization planning program involving mangrove resources must seek a balance between the economic and ecological viewpoints. To achieve this, the current status of the mangrove resource management and utilization should be known in order to identify the kind of important resources, resource users and the problems involving mangroves. As a result the planning program to solve the problems involving mangrove resources could be determined wisely.
*Mahasiswi Universitas Negeri Jakarta
Alumni Bimbingan Pasca Ujian Nasional MataAir Foundation