MORE ABOUT BIODIVERSITY
“Biodiversity” is often defined as the variety of all forms of life, from genes to species, through to the broad scale of ecosystems Biodiversity is the variation of taxonomic life forms within a given ecosystem, biome or for the entire Earth. Biodiversity is often used as a measure of the health of biological systems.Biodiversity is a neologism and a portmanteau word, from biology and diversity. The Science Division of The Nature Conservancy used the term "natural diversity" in a 1975 study, "The Preservation of Natural Diversity." The term biological diversity was used even before that by conservation scientists like Robert E. Jenkins and Thomas Lovejoy. The word biodiversity itself may have been coined by W.G. Rosen in 1985 while planning the National Forum on Biological Diversity organized by the National Research Council (NRC) which was to be held in 1986, and first appeared in a publication in 1988 .The word biodiversity was deemed more effective in terms of communication than biological diversity Since 1986 the terms and the concept have achieved widespread use among biologists, environmentalists, political leaders, and concerned citizens worldwide. It is generally used to equate to a concern for the natural environment and nature conservation. This use has coincided with the expansion of concern over extinction observed in the last decades of the 20th century.
The most straightforward definition is "variation of life at all levels of biological organization". A second definition holds that biodiversity is a measure of the relative diversity among organisms present in different ecosystems. "Diversity" in this definition includes diversity within a species and among species, and comparative diversity among ecosystems.
A third definition that is often used by ecologists is the "totality of genes, species, and ecosystems of a region".
The most straightforward definition is "variation of life at all levels of biological organization". A second definition holds that biodiversity is a measure of the relative diversity among organisms present in different ecosystems. "Diversity" in this definition includes diversity within a species and among species, and comparative diversity among ecosystems.
A third definition that is often used by ecologists is the "totality of genes, species, and ecosystems of a region".
This third definition, which conforms to the traditional five organization layers in biology, provides additional justification for multilevel approaches.
The 1992 United Nations Earth Summit in Rio de Janeiro defined "biodiversity" as "the variability among living organisms from all sources, including, 'inter alia', terrestrial, marine, and other aquatic ecosystems, and the ecological complexes of which they are part: this includes diversity within species, between species and of ecosystems". This is, in fact, the closest thing to a single legally accepted definition of biodiversity, since it is the definition adopted by the United Nations Convention on Biological Diversity.
If the gene is the fundamental unit of natural selection, according to E. O. Wilson, the real biodiversity is genetic diversity. For geneticists, biodiversity is the diversity of genes and organisms. They study processes such as mutations, gene exchanges, and genome dynamics that occur at the DNA level and generate evolution.
For ecologists, biodiversity is also the diversity of durable interactions among species. It not only applies to species, but also to their immediate environment (biotope) and their larger ecoregion. In each ecosystem, living organisms are part of a whole, interacting with not only other organisms, but also with the air, water, and soil that surround them.Biodiversity is a broad concept, so a variety of objective measures have been created in order to empirically measure biodiversity.
The 1992 United Nations Earth Summit in Rio de Janeiro defined "biodiversity" as "the variability among living organisms from all sources, including, 'inter alia', terrestrial, marine, and other aquatic ecosystems, and the ecological complexes of which they are part: this includes diversity within species, between species and of ecosystems". This is, in fact, the closest thing to a single legally accepted definition of biodiversity, since it is the definition adopted by the United Nations Convention on Biological Diversity.
If the gene is the fundamental unit of natural selection, according to E. O. Wilson, the real biodiversity is genetic diversity. For geneticists, biodiversity is the diversity of genes and organisms. They study processes such as mutations, gene exchanges, and genome dynamics that occur at the DNA level and generate evolution.
For ecologists, biodiversity is also the diversity of durable interactions among species. It not only applies to species, but also to their immediate environment (biotope) and their larger ecoregion. In each ecosystem, living organisms are part of a whole, interacting with not only other organisms, but also with the air, water, and soil that surround them.Biodiversity is a broad concept, so a variety of objective measures have been created in order to empirically measure biodiversity.
For practical conservationists, this measure should quantify a value that is broadly shared among locally affected people. For others, a more economically defensible definition should allow the ensuring of continued possibilities for both adaptation and future use by people, assuring environmental sustainability. As a consequence, biologists argue that this measure is likely to be associated with the variety of genes. Since it cannot always be said which genes are more likely to prove beneficial, the best choice for conservation is to assure the persistence of as many genes as possible. For ecologists, this latter approach is sometimes considered too restrictive, as it prohibits ecological succession.
MORE IMPORTANT VALUABLE FACTORS OF BIODIVERSITY
At the ecosystem level, biodiversity provides the conditions and drives the processes that sustain the global economy – and our very survival as a species. The benefits and services provided by ecosystems include:
>> Generation of soils and maintenance of soil quality
The activities of microbial and animal species – including bacteria, algae, fungi, mites, millipedes and worms – condition soils, break down organic matter, and release essential nutrients to plants. These processes play a key role in the cycling of such crucial elements as nitrogen, carbon and phosphorous between the living and non-living parts of the biosphere.
>> Maintenance of air quality
Plant species purify the air and regulate the composition of the atmosphere, recycling vital oxygen and filtering harmful particles resulting from industrial activities.
>> Maintenance of water quality
Wetland ecosystems (swamps, marshes, etc.) absorb and recycle essential nutrients, treat sewage, and cleanse wastes. In estuaries, molluscs remove nutrients from the water, helping to prevent nutrient over-enrichment and its attendant problems, such as eutrophication arising from fertilizer run-off. Trees and forest soils purify water as it flows through forest ecosystems. In preventing soils from being washed away, forests also prevent the harmful siltation of rivers and reservoirs that may arise from erosion and landslides.
>> Pest control
Around 99 per cent of potential crop pests are controlled by a variety of other organisms, including insects, birds and fungi. These natural pesticides are in many ways superior to their artificial equivalents, since pests can often develop resistance to chemical controls.
>> Detoxification and decomposition of wastes
Some 130 billion metric tons of organic waste is processed every year by earth’s decomposing organisms. Many industrial wastes, including detergents, oils, acids and paper, are also detoxified and decomposed by the activities of living things. In soils, the end product of these processes – a range of simple inorganic chemicals – is returned to plants as nutrients. Higher (vascular) plants can themselves serve to remove harmful substances from groundwater.
>> Pollination and crop production
Many flowering plants rely on the activities of various animal species – bees, butterflies, bats, birds, etc. – to help them reproduce through the transportation of pollen. More than one-third of humanity’s food crops depend on this process of natural pollination. Many animal species have evolved to perform an additional function in plant reproduction through the dispersal of seeds.
>> Climate stabilization
Plant tissues and other organic materials within land and ocean ecosystems act as repositories of carbon, helping to slow the build-up of atmospheric carbon dioxide, and thus contributing to climate stabilization. Ecosystems also exert direct influences on regional and local weather patterns. Moisture released into the atmosphere by rainforests, for example, causes regular rainstorms, limiting water loss from the region and helping to control the surface temperature. In cold climates, meanwhile, forests act as insulators and as windbreaks, helping to mitigate the impacts of freezing temperatures.
>> Prevention and mitigation of natural disasters
Forests and grasslands protect landscapes against erosion, nutrient loss, and landslides through the binding action of roots. Ecosystems bordering regularly flooding rivers (floodplain forests and wetlands) help to absorb excess water and thus reduce the damage caused by floods. Certain coastal ecosystems (salt marshes, mangrove forests, etc.) prevent the erosion of coastlines.
>> Provision of food security
Biodiversity provides the vast majority of our foodstuffs. The annual world fish catch, for example (averaging 100 million metric tons), represents humanity’s most important source of wild animal protein, with over 20 per cent of the population in Africa and Asia dependent on fish as their primary source of protein. Terrestrial animals, meanwhile, supply an array of food products: eggs, milk, meat, etc. Wild biodiversity provides a wide variety of important foodstuffs, including fruits, game meats, nuts, mushrooms, honey, spices and flavorings. These wild foods are especially important when agricultural supplies fail. Indeed, wild biodiversity guards against the failure of even the most advanced agricultural systems. For example, the productivity of many of the developed world’s agricultural crops is maintained through the regular assimilation of new genes from wild relatives of these crops. These wild genes offer resistance to the pests and diseases that pose an ever-evolving threat to harvests.
>> Generation of soils and maintenance of soil quality
The activities of microbial and animal species – including bacteria, algae, fungi, mites, millipedes and worms – condition soils, break down organic matter, and release essential nutrients to plants. These processes play a key role in the cycling of such crucial elements as nitrogen, carbon and phosphorous between the living and non-living parts of the biosphere.
>> Maintenance of air quality
Plant species purify the air and regulate the composition of the atmosphere, recycling vital oxygen and filtering harmful particles resulting from industrial activities.
>> Maintenance of water quality
Wetland ecosystems (swamps, marshes, etc.) absorb and recycle essential nutrients, treat sewage, and cleanse wastes. In estuaries, molluscs remove nutrients from the water, helping to prevent nutrient over-enrichment and its attendant problems, such as eutrophication arising from fertilizer run-off. Trees and forest soils purify water as it flows through forest ecosystems. In preventing soils from being washed away, forests also prevent the harmful siltation of rivers and reservoirs that may arise from erosion and landslides.
>> Pest control
Around 99 per cent of potential crop pests are controlled by a variety of other organisms, including insects, birds and fungi. These natural pesticides are in many ways superior to their artificial equivalents, since pests can often develop resistance to chemical controls.
>> Detoxification and decomposition of wastes
Some 130 billion metric tons of organic waste is processed every year by earth’s decomposing organisms. Many industrial wastes, including detergents, oils, acids and paper, are also detoxified and decomposed by the activities of living things. In soils, the end product of these processes – a range of simple inorganic chemicals – is returned to plants as nutrients. Higher (vascular) plants can themselves serve to remove harmful substances from groundwater.
>> Pollination and crop production
Many flowering plants rely on the activities of various animal species – bees, butterflies, bats, birds, etc. – to help them reproduce through the transportation of pollen. More than one-third of humanity’s food crops depend on this process of natural pollination. Many animal species have evolved to perform an additional function in plant reproduction through the dispersal of seeds.
>> Climate stabilization
Plant tissues and other organic materials within land and ocean ecosystems act as repositories of carbon, helping to slow the build-up of atmospheric carbon dioxide, and thus contributing to climate stabilization. Ecosystems also exert direct influences on regional and local weather patterns. Moisture released into the atmosphere by rainforests, for example, causes regular rainstorms, limiting water loss from the region and helping to control the surface temperature. In cold climates, meanwhile, forests act as insulators and as windbreaks, helping to mitigate the impacts of freezing temperatures.
>> Prevention and mitigation of natural disasters
Forests and grasslands protect landscapes against erosion, nutrient loss, and landslides through the binding action of roots. Ecosystems bordering regularly flooding rivers (floodplain forests and wetlands) help to absorb excess water and thus reduce the damage caused by floods. Certain coastal ecosystems (salt marshes, mangrove forests, etc.) prevent the erosion of coastlines.
>> Provision of food security
Biodiversity provides the vast majority of our foodstuffs. The annual world fish catch, for example (averaging 100 million metric tons), represents humanity’s most important source of wild animal protein, with over 20 per cent of the population in Africa and Asia dependent on fish as their primary source of protein. Terrestrial animals, meanwhile, supply an array of food products: eggs, milk, meat, etc. Wild biodiversity provides a wide variety of important foodstuffs, including fruits, game meats, nuts, mushrooms, honey, spices and flavorings. These wild foods are especially important when agricultural supplies fail. Indeed, wild biodiversity guards against the failure of even the most advanced agricultural systems. For example, the productivity of many of the developed world’s agricultural crops is maintained through the regular assimilation of new genes from wild relatives of these crops. These wild genes offer resistance to the pests and diseases that pose an ever-evolving threat to harvests.
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