Principales Politicas Estatales E Internacionales Destinadas A Controlar La Problematica Ambiental

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Etymology
The term biological diversity was used first by wildlife scientist and conservationist Raymond F. Dasmann in the 1968 lay book A Different Kind of Country[7] advocating conservation. The term was widely adopted only after more than a decade, when in the 1980s it came into common usage in science and environmental policy. ThomasLovejoy, in the foreword to the book Conservation Biology,[8] introduced the term to the scientific community. Until then the term "natural diversity" was common, introduced by The Science Division of The Nature Conservancy in an important 1975 study, "The Preservation of Natural Diversity." By the early 1980s TNC's Science program and its head, Robert E. Jenkins,[9] Lovejoy and other leadingconservation scientists at the time in America advocated the use of "biological diversity".
The term's contracted form biodiversity may have been coined by W.G. Rosen in 1985 while planning the 1986 National Forum on Biological Diversity organized by the National Research Council (NRC). It first appeared in a publication in 1988 when sociobiologist E. O. Wilson used it as the title of the proceedings[10] ofthat forum.[11]
Since this period the term has achieved widespread use among biologists, environmentalists, political leaders, and concerned citizens.
A similar term in the United States is "natural heritage." It predates the others and is more accepted by the wider audience interested in conservation. Broader than biodiversity, it includes geology and landforms.-------------------------------------------------
[edit]Definitions

A sampling of fungi collected during summer 2008 in Northern Saskatchewanmixed woods, near LaRonge is an example regarding the species diversity of fungi. In this photo, there are also leaf lichens andmosses.
The terms biological diversity or biodiversity can have many interpretations. It is most commonly used to replace the more clearly defined and longestablished terms, species diversity and species richness. Biologists most often define biodiversity as the "totality of genes, species, and ecosystems of a region".[12][13] An advantage of this definition is that it seems to describe most circumstances and presents a unified view of the traditional three levels at which biological variety has been identified:
* species diversity
*ecosystem diversity
* genetic diversity
In 2003 Professor Anthony Campbell at Cardiff University, UK and the Darwin Centre, Pembrokeshire, defined a fourth level: Molecular Diversity.[14]
This multilevel construct is consistent with Dasmann and Lovejoy. An explicit definition consistent with this interpretation was first given in a paper by Bruce A. Wilcox commissioned by the International Unionfor the Conservation of Nature and Natural Resources (IUCN) for the 1982 World National Parks Conference.[15]Wilcox's definition was "Biological diversity is the variety of life forms...at all levels of biological systems (i.e., molecular, organismic, population, species and ecosystem)...". The 1992 United Nations Earth Summit defined "biological diversity" as "the variability among living organismsfrom 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".[16] This definition is used in the United Nations Convention on Biological Diversity.[16]
One textbook's definition is "variation of life at all levels of biologicalorganization".[17]
Geneticists define it as the diversity of genes and organisms. They study processes such as mutations, gene transfer, and genome dynamics that generate evolution.[15]
Measuring diversity at one level in a group of organisms may not precisely correspond to diversity at other levels. However, tetrapod (terrestrial vertebrates) taxonomic and ecological diversity shows a very close...