There are an estimated 13 to 14 millions species on the planet, but only about 1.75 million of these have been scientifically named and described. Given these figures, the 17,000 plant and animal species threatened with extinction may not seem a lot. Yet 21% of all known mammals, 12% of birds, 37% of all freshwater fish species and 70% of plants are under threat (IUCN, 2009). And, beyond single species, entire ecosystems – like mangroves, tropical forests and coral reefs – are endangered in some parts of the world.
It is not just a question of preserving as wide a range as possible of members of the living world, out of concern for entomological conservation. We now know that biodiversity – genetic diversity within and between species and the diversity of ecosystems – provides a number of “ecosystem services” that are essential for man’s survival, like the pollination of flowers by insects, the role played by mangroves in protecting coastal zones from natural disasters or the absorption of carbon by the oceans. But 60% of these ecosystem services are being damaged or are subject to excessive exploitation (Millennium Ecosystem Assessment, MA, 2005). Some of the damage is thought to be irreversible.
Over the last half century, the rate of biodiversity loss has accelerated noticeably. More land has been converted for agricultural use since 1945 than during the 18th and 19th centuries put together. “Over the past 50 years, humans have changed ecosystems more rapidly and extensively than in any comparable period of time in human history, largely to meet rapidly growing demands for food, freshwater, timber, fibre, and fuel.” (MA, 2005).
Today suffering the aftermath of a terrible earthquake, Haiti has for a long time been faced with a wide-scale ecological disaster. Once covered with trees, only 3% of the island’s forests remain. Deforestation has reduced evaporation into the atmosphere and in many places rainfall has dropped by up to 40%, reducing the flow-rate of rivers and their irrigation capacity. When it does rain, the soil is no longer able to retain the water or to filter it effectively and so the water table and river water, laden with sediments and pollutants, further degrade estuary and coastal ecosystems. Soil erosion is so great that between 1950 and 1990 the amount of arable land decreased by over two fifths.
As is the case in Haiti, it is the poorest who pay the highest price for ecological destruction, as they often depend directly on the services provided by ecosystems. Half of the urban population living in Asia, Africa, Latin America and the Caribbean suffers from one or more illnesses linked to the supply and poor quality of freshwater. As another example, fishing is the main source of animal protein for over a billion people, especially in developing countries (MA, 2005). But half of all fisheries are already fully exploited and a quarter are overexploited (FAO, 2007).
These phenomena are not just being discovered. From the United Nations Conference on the Human Environment (Stockholm, 1972) to the Copenhagen Summit (2009), via the Rio Conference (1992), which gave rise to the Convention on Biological Diversity, a number of international initiatives have hammered home the need to act in order to at least slow down the loss of biodiversity. The International Year of Biodiversity is another opportunity to remind ourselves that doing nothing is not an option.
Source: UNESCOPRESS - Publication Date: 20-01-2010