Despite conservation efforts and development of new mangrove forests, this valuable, bio-diverse ecosystem which is oftentimes ignored, under extreme pressure, continued devastation and loss, deserves our concern and protection. 

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Visitors to islands and coastal areas in a band circling the earth just north and south of the equator are familiar with the dense growth of mangrove trees indigenous to those regions. We probably don't give mangroves much thought, but like everything in nature they serve an extraordinary range of beneficial uses. For example, they are the basis of a complex marine food chain that begins as the leaves drop into tidal waters, are colonized by marine bacteria that convert carbon compounds into a nitrogen-rich detritus that covered with microorganisms becomes food for the smallest animals such as worms, snails, shrimp, mollusks, other shellfish, and larger fish—many of which are harvested by man and some of which are endangered. In addition, mangrove forests provide shelter and breeding habitat, filter and assimilate pollutants from upland runoff, stabilize bottom sediments, improve water quality, and provide important protection against shoreline erosion. There's no question that mangrove zones are important barriers against storm surge and extreme wave action, including tsunamis. The total worldwide mangrove area is estimated at some 170,000 square kilometres and includes some sixty species of trees and shrubs exclusive to the habitat. But as with so many other elements in the coastal zone, mangrove forests are under extreme pressure as a result of toxic poison from waste—both human and industrial—and the increasing value (hence increasing demand) for new coastal land reclaimed for shrimp farming and other aquaculture, waste disposal, industry, residential and leisure development. Some research indicates that more than fifty percent of the world's mangrove forests have succumbed to such pressures in the past twenty five years. Does anybody care? Well, there is, in fact, a mangrove constituency, an international society for mangrove ecosystems that has adopted a charter for mangrove protection that compliments the World Charter for Nature that was proclaimed by the United Nations in 1982 affirming that nature shall be respected, genetic viability on earth shall not be compromised, conservation shall be practiced, sustainable management shall be utilized by man, and nature shall be secured against degradation. It is interesting to note that in the intervals since this proclamation destruction of mangrove environments has continued unabated. Nonetheless there is an effort to protect and reclaim mangrove forests in Florida, in the Caribbean and elsewhere. An interesting experiment is taking place in Eritrea where an effort is under way to restore mangrove trees in traditional areas as a source for foliage fodder for goats and sheep, or for seed that can be dried into a grain-like food staple for humans. Planting, tending, harvesting and use of these by-products are also seen as a strategy to relieve the terrible poverty in that African land. The experiment has extended even into the desert areas where young trees lightly fertilized, irrigated with salt water, and well-drained to protect from the over-concentration of salt have flourished to the point where one might envision a new forest covering large areas previously deemed unfertile, and thereby contributing to CO2 conversion, mitigating climate change, reducing the irrigation demand on the limited local freshwater supply, and providing a new ground for labor and community betterment. Why don't we think of mangroves just as we do rain forests? Isn't it ironic that the hue and cry over clear cutting of trees—the deforestation on land—has been the focus of international conservation organizations and policymakers to an extreme degree, while similar destruction along shore has been almost entirely ignored? When ocean advocates attempt to infiltrate the policy initiatives around forests to include marine plants and habitats under proposed actions and protections, they are routinely rebuffed by bureaucrats and administrators with their jurisdictional boundaries and agency allegiances. In the world environment no single element can be disconnected from the next. A mangrove tree may at first seem irrelevant, but in fact it is the center of a vital nutrient system for marine organisms, a structure that naturally protects and cleanses coastal areas, and an important contributor to human health and well-being in measurable ways and in many places. Mangroves provide the exact same ecosystem services as inland trees, and their continuing devastation and loss deserves our amplified concern.

We will discuss these issues and more in future editions of World Ocean Radio.

Peter Neill, Director of the W2O and host of World Ocean Radio, provides coverage of a broad spectrum of ocean issues from science and education to advocacy and exemplary projects.