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Biodiversity | V-D-P.net - Zo moet techniek @ your service...Biodiversity | V-D-P.net - Zo moet techniek @ your service...Biodiversity is the biological variety and variability of life on Earth. Biodiversity is a measure of variation at the genetic, species, and ecosystem level. Terrestrial biodiversity is usually greater near the equator, which is the result of the warm climate and high primary productivity. Biodiversity is not distributed evenly on Earth, and is richer in the tropics. These tropical forest ecosystems cover less than ten percent of earth's surface, and contain about ninety percent of the world's species. Marine biodiversity is usually higher along coasts in the Western Pacific, where sea surface temperature is highest, and in the mid-latitudinal band in all oceans. There are latitudinal gradients in species diversity. Biodiversity generally tends to cluster in hotspots, and has been increasing through time, but will be likely to slow in the future as a primary result of deforestation. It encompasses the evolutionary, ecological, and cultural processes that sustain life. Rapid environmental changes typically cause mass extinctions. More than 99.9 percent of all species that ever lived on Earth, amounting to over five billion species, are estimated to be extinct. Estimates on the number of Earth's current species range from 10 million to 14 million, of which about 1.2 million have been documented and over 86 percent have not yet been described. The total amount of related DNA base pairs on Earth is estimated at 5.0 x 1037 and weighs 50 billion tonnes. In comparison, the total mass of the biosphere has been estimated to be as much as four trillion tons of carbon. In July 2016, scientists reported identifying a set of 355 genes from the Last Universal Common Ancestor (LUCA) of all organisms living on Earth. The age of the Earth is about 4.54 billion years. The earliest undisputed evidence of life on Earth dates at least from 3.5 billion years ago, during the Eoarchean Era after a geological crust started to solidify following the earlier molten Hadean Eon. There are microbial mat fossils found in 3.48 billion-year-old sandstone discovered in Western Australia. Other early physical evidence of a biogenic substance is graphite in 3.7 billion-year-old meta-sedimentary rocks discovered in Western Greenland. More recently, in 2015, 'remains of biotic life' were found in 4.1 billion-year-old rocks in Western Australia. According to one of the researchers, 'If life arose relatively quickly on Earth .. then it could be common in the universe.' Since life began on Earth, five major mass extinctions and several minor events have led to large and sudden drops in biodiversity. The Phanerozoic eon (the last 540 million years) marked a rapid growth in biodiversity via the Cambrian explosion-a period during which the majority of multicellular phyla first appeared. The next 400 million years included repeated, massive biodiversity losses classified as mass extinction events. In the Carboniferous, rainforest collapse led to a great loss of plant and animal life. The Permian-Triassic extinction event, 251 million years ago, was the worst; vertebrate recovery took 30 million years. The most recent, the Cretaceous-Paleogene extinction event, occurred 65 million years ago and has often attracted more attention than others because it resulted in the extinction of the non-avian dinosaurs. The period since the emergence of humans has displayed an ongoing biodiversity reduction and an accompanying loss of genetic diversity. Named the Holocene extinction, and often referred to as the sixth mass extinction, the reduction is caused primarily by human impacts, particularly habitat destruction. Conversely, biodiversity positively impacts human health in a number of ways, although a few negative effects are studied. The United Nations designated 2011-2020 as the United Nations Decade on Biodiversity. and 2021-2030 as the United Nations Decade on Ecosystem Restoration, According to a 2019 Global Assessment Report on Biodiversity and Ecosystem Services by IPBES 25% of plant and animal species are threatened with extinction as the result of human activity. An October 2020 IPBES report found the same human actions which drive biodiversity loss have also resulted in an increase in pandemics. In 2020, the fifth edition of the UN's Global Biodiversity Outlook report, which served as a 'final report card' for the Aichi Biodiversity Targets, a series of 20 objectives set out in 2010, at the beginning of the UN's Decade on Biodiversity, most of which were supposed to be reached by the end of the year 2020, stated that none of the targets - which concern the safeguarding of ecosystems, and the promotion of sustainability - have been fully met. History of terminology 1916 - The term biological diversity was used first by J. Arthur Harris in 'The Variable Desert,' Scientific American: 'The bare statement that the region contains a flora rich in genera and species and of diverse geographic origin or affinity is entirely inadequate as a description of its real biological diversity.' 1974 - The term natural diversity was introduced by John Terborgh. 1980 - Thomas Lovejoy introduced the term biological diversity to the scientific community in a book. It rapidly became commonly used. 1985 - According to Edward O. Wilson, the contracted form biodiversity was coined by W. G. Rosen: 'The National Forum on BioDiversity ... was conceived by Walter G.Rosen ... Dr. Rosen represented the NRC/NAS throughout the planning stages of the project. Furthermore, he introduced the term biodiversity'. 1985 - The term 'biodiversity' appears in the article, 'A New Plan to Conserve the Earth's Biota' by Laura Tangley. 1988 - The term biodiversity first appeared in a publication. The present - the term has achieved widespread use. Definitions Prior term 'Biodiversity' is most commonly used to replace the more clearly defined and long established terms, species diversity and species richness. Alternate terms Biologists most often define biodiversity as the 'totality of genes, species and ecosystems of a region'. An advantage of this definition is that it seems to describe most circumstances and presents a unified view of the traditional types of biological variety previously identified: taxonomic diversity (usually measured at the species diversity level) ecological diversity (often viewed from the perspective of ecosystem diversity) morphological diversity (which stems from genetic diversity and molecular diversity) functional diversity (which is a measure of the number of functionally disparate species within a population (e.g. different feeding mechanism, different motility, predator vs prey, etc.)) This multilevel construct is consistent with Datman and Lovejoy. Wilcox 1982 An explicit definition consistent with this interpretation was first given in a paper by Bruce A. Wilcox commissioned by the International Union for the Conservation of Nature and Natural Resources (IUCN) for the 1982 World National Parks Conference. 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)...'. Genetic: Wilcox 1984 Biodiversity can be defined genetically as the diversity of alleles, genes and organisms. They study processes such as mutation and gene transfer that drive evolution. United Nations 1992 The 1992 United Nations Earth Summit defined 'biological diversity' 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 definition is used in the United Nations Convention on Biological Diversity. Gaston and Spicer 2004 Gaston & Spicer's definition in their book 'Biodiversity: an introduction' is 'variation of life at all levels of biological organization'. Food and Agriculture Organization 2020 What is forest biological biodiversity? Forest biological diversity is a broad term that refers to all life forms found within forested areas and the ecological roles they perform. As such, forest biological diversity encompasses not just trees, but the multitude of plants, animals and microorganisms that inhabit forest areas and their associated genetic diversity. Forest biological diversity can be considered at different levels, including ecosystem, landscape, species, population and genetic. Complex interactions can occur within and between these levels. In biologically diverse forests, this complexity allows organisms to adapt to continually changing environmental conditions and to maintain ecosystem functions. In the annex to Decision II/9 (CBD, n.d.a), the Conference of the Parties to the CBD recognized that: 'Forest biological diversity results from evolutionary processes over thousands and even millions of years which, in themselves, are driven by ecological forces such as climate, fire, competition and disturbance. Furthermore, the diversity of forest ecosystems (in both physical and biological features) results in high levels of adaptation, a feature of forest ecosystems which is an integral component of their biological diversity. Within specific forest ecosystems, the maintenance of ecological processes is dependent upon the maintenance of their biological diversity.' Distribution Distribution of living terrestrial vertebrate species, highest concentration of diversity shown in red in equatorial regions, declining polewards (towards the blue end of the spectrum) (Mannion 2014) Biodiversity is not evenly distributed, rather it varies greatly across the globe as well as within regions. Among other factors, the diversity of all living things (biota) depends on temperature, precipitation, altitude, soils, geography and the presence of other species. The study of the spatial distribution of organisms, species and ecosystems, is the science of biogeography. Diversity consistently measures higher in the tropics and in other localized regions such as the Cape Floristic Region and lower in polar regions generally. Rain forests that have had wet climates for a long time, such as Yasuni National Park in Ecuador, have particularly high biodiversity. Terrestrial biodiversity is thought to be up to 25 times greater than ocean biodiversity. Forests harbour most of Earth's terrestrial biodiversity. The conservation of the world's biodiversity is thus utterly dependent on the way in which we interact with and use the world's forests. A new method used in 2011, put the total number of species on Earth at 8.7 million, of which 2.1 million were estimated to live in the ocean. However, this estimate seems to under-represent the diversity of microorganisms. Forests provide habitats for 80 percent of amphibian species, 75 percent of bird species and 68 percent of mammal species. About 60 percent of all vascular plants are found in tropical forests. Mangroves provide breeding grounds and nurseries for numerous species of fish and shellfish and help trap sediments that might otherwise adversely affect seagrass beds and coral reefs, which are habitats for many more marine species. The biodiversity of forests varies considerably according to factors such as forest type, geography, climate and soils - in addition to human use. Most forest habitats in temperate regions support relatively few animal and plant species and species that tend to have large geographical distributions, whil