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86-645: The district occupies a total area of 3,108 km (1,200 sq mi) and is divided into seven chiefdoms . Kambia District is overwhelmingly Muslim majority. The population of the district is ethnically diverse. Kambia District is home to the largest population of ethnic Susu in Sierra Leone. Most of the Susu people in Sierra Leone live in Kambia District. The Susu along with the Temne form one of

172-577: A sump to reduce nitrates and other nutrients in the water. Mangroves also appear in home aquariums , and as ornamental plants, such as in Japan . The Manzanar Mangrove Initiative is an ongoing experiment in Arkiko , Eritrea , part of the Manzanar Project founded by Gordon H. Sato , establishing new mangrove plantations on the coastal mudflats . Initial plantings failed, but observation of

258-556: A tropical rainforest biome may contain thousands of tree species, but this is not to say mangrove forests lack diversity. Though the trees are few in species, the ecosystem that these trees create provides a habitat for a great variety of other species, including as many as 174 species of marine megafauna . Mangrove plants require a number of physiological adaptations to overcome the problems of low environmental oxygen levels, high salinity , and frequent tidal flooding . Each species has its own solutions to these problems; this may be

344-603: A 2009 study by the World Resources Institute (WRI) indicates the ecosystems contribute US$ 174 to US$ 249 million per year to Belize's national economy. From 1990, in Tanzania, Adelaida K. Semesi led aresearch programme which resulted in Tanzania being one of the first countries to have an environmental management plan for mangroves. Nicknamed "mama mikoko" ("mama mangroves" in Swahili), Semesi also

430-668: A complex mosaic of adjacent vegetation types such as grasslands, saltmarshes, and woodlands, and this can mean that flexibility in foraging strategy and choice of foraging habitat may be advantageous for highly mobile forest birds. Relative to other forest types, mangroves support few bird species that are obligate habitat (mangrove) specialists and instead host many species with generalised foraging niches. Mangrove forests are home and sanctuaries for many of aquatic bird species, including: The intricate root system of mangrove forests makes them attractive to adult fish seeking food and juvenile fish seeking shelter. Mangrove forests are among

516-641: A drone in days, and at a fraction of the cost. Seventy percent of mangrove forests have been lost in Java , Indonesia . Mangroves formerly protected the island's coastal land from flooding and erosion. Wetlands International , an NGC based in the Netherlands, in collaboration with nine villages in Demak where lands and homes had been flooded, began reviving mangrove forests in Java. Wetlands International introduced

602-538: A habitat for microbial biofilms which are actively involved in different N-cycling pathways such as nitrification, denitrification and dissimilatory nitrate reduction to ammonium (DNRA). Colonizing the carapace of crabs may be advantageous for specific bacteria, because of host activities such as respiration, excretion, feeding and horizontal and vertical migrations. However, the ecological interactions between fiddler crabs and bacteria, their regulation and significance as well as their implications at scales spanning from

688-413: A higher concentration of white mangroves. Mangrove forests are an important part of the cycling and storage of carbon in tropical coastal ecosystems. Knowing this, scientists seek to reconstruct the environment and investigate changes to the coastal ecosystem over thousands of years using sediment cores. However, an additional complication is the imported marine organic matter that also gets deposited in

774-576: A low-cost alternative to wood and charcoal stoves. These may help in reducing the demand for charcoal. Mangroves have been reported to be able to help buffer against tsunami, cyclones, and other storms, and as such may be considered a flagship system for ecosystem-based adaptation to the impacts of climate change. One village in Tamil Nadu was protected from tsunami destruction—the villagers in Naluvedapathy planted 80,244 saplings to get into

860-417: A maximum potential of 0.316996250 Gt (6.9885710 × 10  lb) of CO 2 emissions . Globally, mangroves have been shown to provide measurable economic protections to coastal communities affected by tropical storms. Heterogeneity in landscape ecology is a measure of how different parts of a landscape are from one another. It can manifest in an ecosystem from the abiotic or biotic characteristics of

946-595: A quarter of the destruction of mangrove forests. Likewise, the 2010 update of the World Mangrove Atlas indicated that approximately one fifth of the world's mangrove ecosystems have been lost since 1980, although this rapid loss rate appears to have decreased since 2000 with global losses estimated at between 0.16% and 0.39% annually between 2000 and 2012. Despite global loss rates decreasing since 2000, Southeast Asia remains an area of concern with loss rates between 3.6% and 8.1% between 2000 and 2012. By far

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1032-529: A small piece of iron and a pierced plastic bag with fertilizer containing nitrogen and phosphorus are buried with the propagule. As of 2007 , after six years of planting, 700,000 mangroves are growing; providing stock feed for sheep and habitat for oysters, crabs, other bivalves, and fish. Another method of restoring mangroves is by using quadcopters (which are able to carry and deposit seed pods). According to Irina Fedorenko, an amount of work equivalent to weeks of planting using traditional methods can be done by

1118-712: Is already occurring. The fine, anoxic sediments under mangroves act as sinks for a variety of heavy (trace) metals which colloidal particles in the sediments have concentrated from the water. Mangrove removal disturbs these underlying sediments, often creating problems of trace metal contamination of seawater and organisms of the area. Mangrove swamps protect coastal areas from erosion , storm surge (especially during tropical cyclones ), and tsunamis . They limit high-energy wave erosion mainly during events such as storm surges and tsunamis. The mangroves' massive root systems are efficient at dissipating wave energy. Likewise, they slow down tidal water enough so that its sediment

1204-497: Is deposited as the tide comes in, leaving all except fine particles when the tide ebbs. In this way, mangroves build their environments. Because of the uniqueness of mangrove ecosystems and the protection against erosion they provide, they are often the object of conservation programs, including national biodiversity action plans . Worldwide there are about 80 described species of mangroves that live along marine coasts. About 60 of these species are true mangroves which live only in

1290-413: Is intersected by a complex network of tidal waterways, mudflats and small islands of salt-tolerant mangrove forests. The interconnected network of waterways makes almost every portion of the forest accessible by boat. The area is known as an important habitat for the endangered Bengal tiger , as well as numerous fauna including species of birds, spotted deer , crocodiles and snakes. The fertile soils of

1376-407: Is more readily consumed in the interior of the mangrove forest. Anthropogenic inputs may push the limits of survival in many mangrove microhabitats. For example, shrimp ponds constructed in mangrove forests are considered the greatest anthropogenic threat to mangrove ecosystems. These shrimp ponds reduce estuary circulation and water quality which leads to the promotion of diel-cycling hypoxia. When

1462-418: Is not becoming more carbon dense, then carbon has to be lost at a rate equal to the amount of carbon fixed as NPP. Hence this productivity is either retained within the mangrove forest, as a standing stock of live material such as wood, buried in sediments , or exported to neighbouring habitats as litter, particulate and dissolved organic carbon (POC and DOC) and dissolved inorganic carbon (DIC), or lost to

1548-463: Is only available for about half of the global area of mangroves. However, of those areas for which data has been collected, it appears that 35% of the mangroves have been destroyed. Since the 1980s, around 2% of mangrove area is estimated to be lost each year. Assessments of global variation in mangrove loss indicates that national regulatory quality mediates how different drivers and pressures influence loss rates. Shrimp farming causes approximately

1634-497: Is that the large majority of these young people are unemployed. A small proportion of them survive on occasional casual labour opportunities as porters, cleaners and dancers. But by far their most important sources of survival are the smuggling of goods, mostly drugs, alcohol, cigarettes and light arms across the border, juvenile delinquencies, and as sex workers and concubines of the large number of national armies, peace-keeping forces, Para-militaries and long distance travellers. Since

1720-416: Is used, as this is connected to the sea and subjected to the tides, and less diseases occur, and as far less mangrove is destroyed for it. Grassroots efforts to protect mangroves from development and from citizens cutting down the mangroves for charcoal production , cooking, heating and as a building material are becoming more popular. Solar cookers are distributed by many non-government organizations as

1806-627: The British colonial administration when it organised the Protectorate of Sierra Leone in 1896. Typically, chiefs have the power to "raise taxes, control the judicial system, and allocate land, the most important resource in rural areas." The hereditary paramount chiefs and their sub-chiefs were the sole local government in Sierra Leone until 2004, when the World Bank sponsored the creation of elected local councils. Local notables, known as

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1892-689: The Guinness Book of World Records . This created a kilometre-wide belt of trees of various varieties. When the 2004 tsunami struck, much of the land around the village was flooded, but the village suffered minimal damage. Compared to seagrass meadows and coral reefs , hypoxia is more common on a regular basis in mangrove ecosystems, through ocean deoxygenation is compounding the negative effects by anthropogenic nutrient inputs and land use modification. Like seagrass, mangrove trees transport oxygen to roots of rhizomes , reduce sulfide concentrations, and alter microbial communities. Dissolved oxygen

1978-629: The Sierra Leonean parliament , of which six were elected for a 5-year term. The district is stronghold of the National Grand Coalition Party (NGC). Following is a list of the 7 Representatives and their affiliations: Prior to the 2017 local administrative reorganization, Kambia District was made up of seven chiefdoms as the third level of administrative subdivision. After the 2017 local administrative reorganization, Kambia District has made up of ten chiefdoms as

2064-652: The Temne , Susu , Limba , Fula and Mandingo . Kambia District is home to several international health operations, including the International Medical Corps who arrived in 2001, Kambia Appeal , a United Kingdom -based non-profit organization that has operated in Kambia since 1992 and Doctors without Borders , a France -based medical non-profit agency that operates across the world in poverty-stricken areas. The District has seven representatives in

2150-400: The red , white , and black mangroves occupy different ecological niches and have slightly different chemical compositions, so the carbon content varies between the species, as well between the different tissues of the plant (e.g., leaf matter versus roots). There is a clear succession of these three trees from the lower elevations, which are dominated by red mangroves, to farther inland with

2236-519: The 5° N and 5° S latitudes. Approximately 75% of world's mangroves are found in just 15 countries. Estimates of mangrove area based on remote sensing and global data tend to be lower than estimates based on literature and surveys for comparable periods. In 2018, the Global Mangrove Watch Initiative released a global baseline based on remote sensing and global data for 2010. They estimated the total mangrove forest area of

2322-537: The Indian Sundarbans were assessed as endangered in 2020 under the IUCN Red List of Ecosystems framework. There is a consistent pattern of depleted biodiversity or loss of species and the ecological quality of the forest is declining. The unique ecosystem found in the intricate mesh of mangrove roots offers a quiet marine habitat for young organisms. In areas where roots are permanently submerged,

2408-1414: The Tribal Authority, elect paramount chiefs for life from among the ruling families in each chieftaincy recognised by the British administration in 1896. Some chieftaincies have several ruling families, and the differences among them in terms of economic progress has been subject to study in 2013. They found there was a positive relationship between the number of ruling families in a chieftaincy and educational, health and economic outcomes in terms of human capital . The districts of Sierra Leone were divided into 149 chiefdoms of chieftaincies until 2017, as listed below as of 2011. Since 2017, they have been divided into 190 chiefdoms. Mangrove swamp Mangrove forests , also called mangrove swamps , mangrove thickets or mangals , are productive wetlands that occur in coastal intertidal zones . Mangrove forests grow mainly at tropical and subtropical latitudes because mangrove trees cannot withstand freezing temperatures. There are about 80 different species of mangroves, all of which grow in areas with low-oxygen soil, where slow-moving waters allow fine sediments to accumulate. Many mangrove forests can be recognised by their dense tangle of prop roots that make

2494-479: The abundant Ocipodid crabs, mainly represented by fiddler crabs, do not permanently ventilate their burrows. These crabs may temporarily leave their burrows for surface activities, or otherwise plug their burrow entrance during tidal inundation in order to trap air. A recent study showed that these crabs can be associated with a diverse microbial community, either on their carapace or in their gut. The exoskeleton of living animals, such as shells or carapaces, offers

2580-425: The amount of carbon fixed by mangroves normally greatly exceeds the amount stored within the forest, although the scale of outwelling varies considerably between forests, due to differences in coastal geomorphology , tidal regimes, freshwater flow and productivity. In the 1990s, global estimates could account for 48% of the total global mangrove primary production of 218 ± 72 million tons C yr (see diagram on

2666-487: The areas where mangroves did survive by themselves led to the conclusion that nutrients in water flow from inland were important to the health of the mangroves. Trials with the Eritrean Ministry of Fisheries followed, and a planting system was designed to provide the nitrogen, phosphorus, and iron missing from seawater. The propagules are planted inside a reused galvanized steel can with the bottom knocked out;

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2752-410: The atmosphere. The outwelling hypothesis argues that export of locally derived POC and DOC is an important ecosystem function of mangroves, which drives detrital based food webs in adjacent coastal habitats. Export of mangrove carbon has been estimated to make a significant trophic contribution to adjacent ecosystems. The theory of outwelling is supported by mass balance evaluations that show

2838-1102: The availability of energy-yielding electron acceptors and increase nitrogen turnover via direct excretion. Thus, macrofauna may alleviate nitrogen limitation by priming the remineralisation of refractory nitrogen (that is, the nitrogen that can't be biologically decomposed), reducing plant-microbe competition. Such activity ultimately promotes nitrogen recycling, plant assimilation and high nitrogen retention, as well as favours its loss by stimulating coupled nitrification and denitrification . Mangrove sediments are highly bioturbated by decapods such as crabs. Crab populations continuously rework sediment by constructing burrows, creating new niches, transporting or selectively grazing on sediment microbial communities. In addition, crabs can affect organic matter turnover by assimilating leaves and producing finely fragmented faeces, or by carrying them into their burrows. Therefore, crabs are considered important ecosystem engineers shaping biogeochemical processes in intertidal muddy banks of mangroves. In contrast to burrowing polychaetes or amphipods,

2924-402: The border were the principal sellers in such markets, travelling from one town and village to the other. However men are increasingly participating in commerce and a pattern of division of labour between sexes can be observed as the women trade mainly in agricultural products and processed food items while the men trade mainly in imported consumer goods. Kambia District was the last to experience

3010-653: The border. Although disrupted during the war, these weekly markets have resumed and increased in number from 5 in the pre-war period to 15, with traders coming from various parts of both countries, from as far as Conakry, Nzerekore, Macenta and Faranah in Guinea and from provincial Headquarters towns of Bo, Kenema, Kono, Makeni and the capital city of Freetown, giving these village markets a true international character. The products offered are mainly agricultural and food products, clothes and some imported consumer goods. Like other commercial activities, women traders from both sides of

3096-451: The brushwood, it serves to catch floating mangrove seeds and provide them with a stable base to germinate, take root and regrow. This creates a green belt of protection around the islands. As the mangroves mature, more sediment is held in the catchment area; the process is repeated until a mangrove forest has been restored. Eventually the protective structures will not be needed. By late 2018, 16 km (9.9 mi) of brushwood barriers along

3182-429: The chemistry of this peat and represent approximately 2% of above ground carbon storage in mangroves. As the nests are buried over time this carbon is stored in the sediment, and the carbon cycle continues. Mangroves are an important source of blue carbon . Globally, mangroves stored 4.19 Gt (9.2 × 10  lb) of carbon in 2012. Two percent of global mangrove carbon was lost between 2000 and 2012, equivalent to

3268-477: The civil conflict. Over 60% of these refugees originated from the Kambia district. It is estimated that more than 90% of them have now returned to their various communities in the district. Secondly, in addition to the domestic war, most of the heavy fighting between the Guinean troops and the rebels to dislodge the invading rebel forces from Guinea occurred in the district. As a result, the district suffered one of

3354-655: The civil war, with the first wave of attacks by the Revolutionary United Front (RUF) in January 1995 and later in 1998. Finally, in February 1999, the rebels occupied all the major towns in the district including the headquarters town of Kambia until disarmament in May 2001. It is also here that the reintegration efforts have been less successful and have fallen victim to donor fatigue. In the early phase of

3440-410: The coastline had been completed. A concern over reforestation is that although it supports increases in mangrove area it may actually result in a decrease in global mangrove functionality and poor restoration processes may result in longer term depletion of the mangrove resource. In terms of local and national studies of mangrove loss, the case of Belize's mangroves is illustrative in its contrast to

3526-461: The community especially young people with little alternative means of subsistence. Chiefdoms of Sierra Leone The chiefdoms of Sierra Leone are the third-level units of administration in Sierra Leone . There are 190 chiefdoms in Sierra Leone, as of 2017. Previously, there were 149. The paramount chiefs and the ruling families in the chiefdoms were recognised and empowered by

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3612-412: The country. There are 13 secondary schools in the district, located in Kambia town, Rokupr, Kasirie, Kychom, Mambolo, Tombowala, Madina, Kamassassa and Kukuna; three of the 13 of the secondary schools together with the hospital were all burnt down in February 1999 during the intensive fighting in the district, while the remaining 10 were systematically vandalised to an extent of completely ruining them. As

3698-500: The delta have been subject to intensive human use for centuries, and the ecoregion has been mostly converted to intensive agriculture, with few enclaves of forest remaining. Additionally, the Sundarbans serves a crucial function as a protective barrier for millions of inhabitants against floods that result from cyclones . Four protected areas in the Sundarbans are listed as UNESCO World Heritage Sites . Despite these protections,

3784-440: The district has an impressive potential for upland, inland valley swamp and mangrove swamp farming. The population is mainly farmers , practising off-season activities such as gardening, hunting and as migrant labour. The major food crops grown by the people are, rice (the staple food), cassava, millet, sweet potatoes and sorghum, while groundnuts and maize constitute the major cash crops. In addition to farming, fishing along

3870-457: The district was hit later by the war than most other areas of Sierra Leone, it hosted a huge number of Internally Displaced Persons (IDPs) until September 1998 when it sustained a heavy rebel attack by the RUF rebel fighters. Much of the population, together with over 40,000 IDPs who had sought refuge in the district fled to neighbouring Guinea. The inhabitants of this district constitute the majority of

3956-456: The end of the war in both countries early 2002, the district has witnessed regular and large-scale movements of people across the border. The reasons include the return of thousands of refugees and visits by relatives. But by far the most important factor is the rapid revival of the cross-border trade in the traditional weekly market towns and villages on both sides of the border. These markets, traditionally known as ‘Loumah’ have increased from 5 in

4042-582: The environment. For example, coastal mangrove forests are located at the land-sea interface, so their functioning is influenced by abiotic factors such as tides, as well as biotic factors such as the extent and configuration of adjacent vegetation. For forest birds, tidal inundation means that the availability of many mangrove resources fluctuates daily, suggesting foraging flexibility is likely to be important. Mangroves also offer estuarine prey items, such as mudskippers and crabs, that are not found in terrestrial forest types. Further, mangroves are often situated in

4128-444: The equator because they cannot withstand freezing temperatures. Many mangrove forests can be recognised by their dense tangle of prop roots that make the trees appear to be standing on stilts above the water. This tangle of roots allows the trees to handle the daily rise and fall of tides, which means that most mangroves get flooded at least twice per day. The roots slow the movement of tidal waters , causing sediments to settle out of

4214-549: The fish trade is completely dominated by the women. Animal raising of sheep and goats on small-scale units has declined because of forced sales in order to compensate for the chronic fall in agricultural production and the subsequent rural poverty. Cattle rearing by groups of resident Fullahs in the North-east of the district has similarly disappeared as they have migrated to Guinea, due to the protracted civil war. An FAO report in 1996 stated that 40% of Sierra Leonean livestock

4300-975: The global picture. A recent, satellite-based study —funded by the World Wildlife Fund and conducted by the Water Center for the Humid Tropics of Latin America and the Caribbean (CATHALAC)—indicates Belize's mangrove cover declined by a mere 2% over a 30-year period. The study was born out of the need to verify the popular conception that mangrove clearing in Belize was rampant. Instead, the assessment showed, between 1980 and 2010, under 16 km (6.2 sq mi) of mangroves had been cleared, although clearing of mangroves near Belize's main coastal settlements (e.g. Belize City and San Pedro)

4386-550: The highest rates of population displacement and possibly the worst infrastructure destruction. It is also significant to note that, the rebel invasion of Kambia town in 1995 was one of the first occasions in which children were abducted in large numbers since all the schools were in session when the town was invaded. Most of these children are now young adults and have returned to the community without passing through any formal demobilisation process and with very little resettlement and social reintegration support. A major consideration

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4472-527: The idea of developing tropical versions of techniques traditionally used by the Dutch to catch sediment in North Sea coastal salt marshes. Originally, the villagers constructed a sea barrier by hammering two rows of vertical bamboo poles into the seabed and filling the gaps with brushwood held in place with netting. Later the bamboo was replaced by PVC pipes filled with concrete. As sediment gets deposited around

4558-998: The interface between the land, the ocean, and the atmosphere, and are centres for the flow of energy and matter between these systems. They have attracted much research interest because of the various ecological functions of the mangrove ecosystems, including runoff and flood prevention, storage and recycling of nutrients and wastes, cultivation and energy conversion. The forests are major blue carbon systems, storing considerable amounts of carbon in marine sediments , thus becoming important regulators of climate change . Marine microorganisms are key parts of these mangrove ecosystems. However, much remains to be discovered about how mangrove microbiomes contribute to high ecosystem productivity and efficient cycling of elements. There are about 80 different species of mangrove trees. All of these trees grow in areas with low-oxygen soil, where slow-moving waters allow fine sediments to accumulate. Mangrove forests grow only at tropical and subtropical latitudes near

4644-526: The intertidal zone between high and low tides. "Mangroves once covered three-quarters of the world's tropical coastlines, with Southeast Asia hosting the greatest diversity. Only 12 species live in the Americas. Mangroves range in size from small bushes to the 60-meter giants found in Ecuador. Within a given mangrove forest, different species occupy distinct niches. Those that can handle tidal soakings grow in

4730-427: The largest ethnic groups in the district. Before the British and Portuguese arrived in Sierra Leone, a farmer and hunter named Pa Kambi settled on the banks of the river where Kambia lies today. As other natives from neighboring locales wandered about, they discovered Pa Kambi thriving on his trades. They, too, decided to settle down and named the area Kambia, meaning the town of Pa Kambi. The Kambia District

4816-475: The local fish populations, which are an essential food source. The environmental costs of shrimp farms in the mangrove forests grossly outweigh the economic benefits of them. Cessation of shrimp production and restoration of these areas reduce eutrophication and anthropogenic hypoxia. In some areas, mangrove reforestation and mangrove restoration is also underway. Red mangroves are the most common choice for cultivation, used particularly in marine aquariums in

4902-403: The many river estuaries and streams is practised by a large proportion of the population of the district. Fishing is an important source of income for the district, as traders come from other areas on both sides of the border to the fishing Islands and enclaves. This sector more than any other, demonstrates the division of labour between men and women in the community. While the men are the fishers,

4988-511: The more productive and diverse ecosystems on the planet, despite limited nitrogen availability. Under such conditions, animal-microbe associations ( holobionts ) are often key to ecosystem functioning. An example is the role of fiddler crabs and their carapace -associated microbial biofilm as hotspots of microbial nitrogen transformations and sources of nitrogen within the mangrove ecosystem. Among coastal ecosystems, mangrove forests are of great importance as they account for three quarters of

5074-398: The most damaging form of shrimp farming is when a closed ponds system (non- integrated multi-trophic aquaculture ) is used, as these require destruction of a large part of the mangrove, and use antibiotics and disinfectants to suppress diseases that occur in this system, and which may also leak into the surrounding environment. Far less damage occurs when integrated mangrove-shrimp aquaculture

5160-405: The nitrogen supply was unlimited. In addition to species variation, different environmental conditions can also affect the nitrogen assimilation rates in mangrove plants. Because Cl ions can reduce protein synthesis and nitrogen assimilation , soil pore water salinity appears to be a negative factor that significantly alters the nitrogen uptake rates of mangrove plants. Adequate data

5246-434: The number of street children, since few families could afford sufficient food. The current low levels of agricultural production and poor harvest of rice (the staple food) and groundnuts (the most important commercial crop for the district) are bound to reduce income even further and exacerbate the food problem. Similarly, support for income generation activities and self-employment opportunities are lacking, leaving members of

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5332-415: The open sea, in sheltered bays, and on fringe islands. Trees adapted to drier, less salty soil can be found farther from the shoreline. Some mangroves flourish along riverbanks far inland, as long as the freshwater current is met by ocean tides." Mangroves can be found in 118 countries and territories in the tropical and subtropical regions of the world. The largest percentage of mangroves is found between

5418-596: The organic matter produced and retained in mangroves can slow the recycling of nutrients, particularly of nitrogen. Nitrogen limitation in such systems may be overcome by microbial nitrogen fixation when combined with high rates of bioturbation by macrofauna , such as crabs and lobsters. Bioturbation by macrofauna affect nitrogen availability and multiple nitrogen related microbial processes through sediment reworking, burrow construction and bioirrigation , feeding and excretion. Macrofauna mix old and fresh organic matter, extend oxic–anoxic sediment interfaces, increase

5504-542: The organisms they host include algae , barnacles , oysters , sponges , and bryozoa , which all require a hard surface for anchoring while they filter-feed. Shrimp and mud lobsters use the muddy bottoms as their home. Mangrove crabs eat the mangrove leaves, adding nutrients to the mangal mud for other bottom feeders. In at least some cases, the export of carbon fixed in mangroves is important in coastal food webs. Mangrove plantations host several commercially important species of fish and crustaceans. In Puerto Rico ,

5590-661: The plant litter and break it down chemically into organic compounds , minerals, carbon dioxide, and nitrogenous wastes . The intertidal existence to which these trees are adapted represents the major limitation to the number of species able to thrive in their habitat. High tide brings in salt water, and when the tide recedes, solar evaporation of the seawater in the soil leads to further increases in salinity. The return of tide can flush out these soils, bringing them back to salinity levels comparable to that of seawater. At low tide, organisms are exposed to increases in temperature and reduced moisture before being then cooled and flooded by

5676-616: The pre-war period to 15. Moreover, they now attract thousands of traders and other visitors from large and far-off towns including the capital cities (Freetown and Conakry) and mining areas of both countries. In addition to the Loumah towns and villages, the district also has several large towns such as Rokupr, Mambolo, Kassiri, Kukuna, Kamassassa, Kychom and Yeliboya that are famous for their trade in fish and agricultural produce such as rice, groundnuts, palmoil and pepper and as ports for inland water transportation to destinations in both Guinea and

5762-587: The primary reason why, on some shorelines, mangrove tree species show distinct zonation. Small environmental variations within a mangal may lead to greatly differing methods for coping with the environment. Therefore, the mix of species is partly determined by the tolerances of individual species to physical conditions, such as tidal flooding and salinity, but may also be influenced by other factors, such as crabs preying on plant seedlings. Once established, mangrove roots provide an oyster habitat and slow water flow, thereby enhancing sediment deposition in areas where it

5848-416: The quality of the water degrades, the shrimp ponds are quickly abandoned leaving massive amounts of wastewater. This is a major source of water pollution that promotes ocean deoxygenation in the adjacent habitats. Due to these frequent hypoxic conditions, the water does not provide habitats to fish. When exposed to extreme hypoxia, ecosystem function can completely collapse. Extreme deoxygenation will affect

5934-500: The refugees in the Forecariah prefecture (District). The district is considered as the main rice bowl of Sierra Leone. It has a large agricultural zone with extensive swamp areas found in every chiefdom, but more in the south-west, dominated by mangroves and large river estuaries. The rest of the vegetation consists of a mix between forest to the south and grassland or savannah to the north east. With annual rainfall above 2,500mm,

6020-415: The rest of Sierra Leone, including the capitals of Freetown and Conakry. These factors have encouraged a relatively large concentration of young people in these towns. Discussions with members of the community indicated that in addition to the consequences of the civil war, a major problem is the insufficient support for food production. Food scarcity is widespread and is one of the reasons for an increase in

6106-472: The right). By incorporating information on carbon burial, CO 2 efflux and carbon outwelled as leaf litter , POC and DOC, the remaining 52% was thought outwelled as DIC, though there was insufficient data to confirm this. More recent assessments of DIC export at two sites in Australia ; supported the estimates of Bouillon et al. in 2008, although in 2014 Alongi suggested that only 40% of NPP

6192-495: The sediment through the tidal flushing of mangrove forests. Mangrove forests can decay into peat deposits because of fungal and bacterial processes as well as by the action of termites . It becomes peat in good geochemical , sedimentary, and tectonic conditions. The nature of these deposits depends on the environment and the types of mangroves involved. Termites process fallen leaf litter , root systems and wood from mangroves into peat to build their nests. Termites stabilise

6278-406: The single individual to the ecosystem are not well understood. Mangrove forests are amongst the world's most productive marine ecosystems, with net primary productivity (NPP) in the order of 208 Tg C yr . Mangrove forests achieve a steady state once the forest reaches maximum biomass at around 20–30 years through a constant process of mortality and renewal  so, assuming the living biomass

6364-418: The third level of administrative subdivision. All the chiefdoms had medical centres or posts with the only referral hospital located in Kambia town, the district headquarters town. There are less transport facilities in almost all these places to the headquarters town. This made it possible for the highest number of death rate especially infant and maternal mortality in Kambia than all other districts in

6450-443: The tide. Thus, for a plant to survive in this environment, it must tolerate broad ranges of salinity, temperature, and moisture, as well as several other key environmental factors—thus only a select few species make up the mangrove tree community. A mangrove swamp typically features only a small number of tree species. It is not uncommon for a mangrove forest in the Caribbean to feature only three or four tree species. For comparison,

6536-595: The trees appear to be standing on stilts above the water. This tangle of roots allows the trees to handle the daily rise and fall of tides, as most mangroves get flooded at least twice per day. The roots slow the movement of tidal waters, causing sediments to settle out of the water and build up the muddy bottom. Mangrove forests stabilise the coastline, reducing erosion from storm surges , currents, waves, and tides. The intricate root system of mangroves also makes these forests attractive to fish and other organisms seeking food and shelter from predators. Mangrove forests live at

6622-449: The tropical coastline and provide different ecosystem services. Mangrove ecosystems generally act as a net sink of carbon, although they release organic matter to the sea in the form of dissolved refractory macromolecules, leaves, branches and other debris. In pristine environments, mangroves are among the most productive ecosystems on the planet, despite growing in tropical waters that are often nutrient depleted. The refractory nature of

6708-527: The war, this border district functioned as host for a large number of internally displaced persons and transit zones for refugees. Later in the war, it became an operational zone and no-man's land for fighters of various factions. During the last year of the war and the disarmament period, it became the station for thousands of International peacekeeping forces (ECOMOG and UNAMSIL). Similarly the neighbouring district of Forecariah has been host to over 210,000 officially registered refugees (residing in 10 camps) during

6794-472: The water and build up the muddy bottom. Mangrove forests stabilise the coastline, reducing erosion from storm surges, currents, waves, and tides. The intricate root system of mangroves makes these forests attractive to fishes and other organisms seeking food and shelter from predators. The main contribution of mangroves to the larger ecosystem comes from litter fall from the trees, which is then decomposed by primary consumers . Bacteria and protozoans colonise

6880-516: The world as of 2010 at 137,600 km (53,100 sq mi), spanning 118 countries and territories. Following the conventions for identifying geographic regions from the Ramsar Convention on Wetlands, researchers reported that Asia has the largest share (38.7%) of the world's mangroves, followed by Latin America and the Caribbean (20.3%), Africa (20.0%), Oceania (11.9%), and Northern America (8.4%). The largest mangrove forest in

6966-755: The world is in the Sundarbans . The Sundarban forest lies in the vast delta on the Bay of Bengal formed by the super confluence of the Brahmaputra and Meghna rivers with distributaries of the Ganges . The seasonally flooded Sundarbans freshwater swamp forests lie inland from the mangrove forests on the coastal fringe. The forest covers 10,000 km (3,900 sq mi) of which about 6,000 km (2,300 sq mi) are in Bangladesh. The Sundarbans

7052-483: Was a Council Member for the International Society for Mangrove Ecosystems . In May 2019, ORNL DAAC News announced that NASA 's Carbon Monitoring System (CMS), using new satellite-based maps of global mangrove forests across 116 countries, had created a new dataset to characterize the "distribution, biomass, and canopy height of mangrove-forested wetlands". Mangrove forests move carbon dioxide "from

7138-610: Was exported as DIC. Mangrove forests and coastal marshes are typically considered N-limited ecosystems because of their high primary production. Therefore, mangrove plants are highly efficient at utilising soil nitrogen, making them an important sink for excess nitrogen from upstream. However, different mangrove species may still utilise nitrogen at different efficiencies, even though they share similar nitrogen pathways (see diagram on right). Reported nitrogen assimilation rates in mangrove plants ranged from 2 to 8 μmol g h under ambient nitrogen conditions, and 19 to 251 μmol g h when

7224-403: Was formed in 1928 as a split of the now-defunct Karene District and Port Loko District . Population in the district has increased steadily over the past 42 years: from 137,806 in 1963, to 155,341 in 1974 to 186,231 in 1985 to the 2004 population of 270,460. The district is inhabited by many of Sierra Leone's ethnic groups, however the largest and most prominent ethnic groups in the district are

7310-401: Was now in Guinea. Outside agriculture, commerce is probably the most important source of income for the population. In addition to domestic trade, cross-border trade expanded to all the different chiefdoms in the district. This is due mainly to the growth of outside agriculture; commerce is probably the most important source of the traditional weekly market villages known as the "LOUMAH" along

7396-400: Was relatively high. The rate of loss of Belize's mangroves—at 0.07% per year between 1980 and 2010—was much lower than Belize's overall rate of forest clearing (0.6% per year in the same period). These findings can also be interpreted to indicate Belize's mangrove regulations (under the nation's) have largely been effective. Nevertheless, the need to protect Belize's mangroves is imperative, as

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