Salt Marsh and Mangroves (for Coastal Defence) Essay

Salt Marsh and Mangroves (for Coastal Defence) - Essay Example Mangroves provide a good site for fisheries as the nursery grounds for young fish (fingerlings) and for laying their eggs. Mangrove forest cover is a crucial part of the bio-diversity of a locality such as giving a good habitat for a host of marine life. This is proven by the presence of three types of fauna found in mangroves which are resident species (living primarily among the mangroves), the seasonal migrants and the occasional species which visit the mangrove stands once in a while. The scientific study of mangroves and salt marsh as part of the conservation efforts is now a recognized field in engineering and of studies in ecology and oceanography. Mangrove forests are natural ecosystems in many coastal areas around the world and provide a natural coastal defence system which is often overlooked by country planners. Mangroves are a good deterrent against erosion caused by higher sea levels due to global warming and a changed wind pattern from various directions and velocities. Unfortunately, mangroves are under threat today from human activities and expansion. This paper will discuss how mangroves and salt marsh are crucial components in the coastal defence of areas threatened with erosion from tides and strong winds. It will then also tackle other issues concerning mangrove forests such as clearing them for firewood, charcoal and the other human needs such as for certain coastal developments like resorts. (Crossland & Kremer 47). Humans today are increasingly seen as major catalysts for change among coastal processes which had not been examined very closely before. Human interventions in areas of the coast form part of the larger anthropocene in which larger ecosystems are impacted. Various threats to Mangrove Forests – mangroves are under pressure from us humans especially in developed mangrove areas of the world such as those located along the Niger and delta areas of the Ganges-Brahmaputra and the Irrawaddy in Burma (Kathiresan 476). Other threats identified are degradation and destruction of the mangroves, plant disease and glo bal warming from climate changes. Some 90% of identified global mangroves are located in developing countries which make these mangrove forests particularly vulnerable to human exploitation and expansion of human activities. The estimated 18 million kms2 of mangroves in 1997 has since been reduced to a mere 15 million square-kilometres; it takes a long time for mangrove forests to recover once these are destroyed. Human Encroachments – this is perhaps the greatest threat to mangroves due to the various activities of humans such as urbanization (like in Singapore), Bangkok, Rangoon and in India (Calcutta and Bombay). Another is agricultural expansion from reclamation activities and for aquaculture purposes such as building ponds for shrimps. Other reasons are cutting the mangroves for firewood, charcoal and lumber (mangrove timber is highly resistant to the usual deterioration of wood because of high phenol content). The mangrove areas are usually drained of their salt water c ontent using rain water and protected from salt water intrusions. Degradation – this results when the health and productivity of the mangrove areas had deteriorated significantly from various causes. Among identified causes are oil pollution, dumped