Biodiversité
Définition(s)
Définitions générales
| La biodiversité, néologisme composé à partir des mots bio (du grec βίος / bios, « vie ») et diversité, est la diversité naturelle des organismes vivants. Elle s'apprécie en considérant la diversité des écosystèmes, des espèces, et des gènes dans l'espace et dans le temps, ainsi que les interactions au sein de ces niveaux d'organisation et entre eux.Depuis le sommet de la Terre de Rio de Janeiro en 1992, la préservation de la biodiversité est considérée comme un des enjeux essentiels du développement durable. L'adoption de la Convention sur la diversité biologique (CDB) au cours de ce sommet engage les pays signataires à protéger et restaurer la diversité du vivant. Au-delà des raisons éthiques, la biodiversité est essentielle aux sociétés humaines qui en sont entièrement dépendantes à travers les services écosystémiques.Depuis 2012, la Plate-forme intergouvernementale sur la biodiversité et les services écosystémiques (IPBES), un groupe d'experts intergouvernemental sur le modèle du Groupe d'experts intergouvernemental sur l'évolution du climat (GIEC), a été lancé par le programme des Nations unies pour l'environnement pour conseiller les gouvernements sur cette thématique.2010 a été l'année internationale de la biodiversité, conclue par la conférence de Nagoya sur la biodiversité qui a reconnu l'échec de l'objectif international qui était de stopper la régression de la biodiversité avant 2010, et proposé de nouveaux objectifs (protocole de Nagoya). |
Termes associés (Wikipedia)
| Life timelineview • discuss • -4500 —–-4000 —–-3500 —–-3000 —–-2500 —–-2000 —–-1500 —–-1000 —–-500 —–0 —waterSingle-celledlifephotosynthesisEukaryotesMulticellularlifeLand lifeDinosaurs MammalsFlowers ←Earliest Earth (-4540)←Earliest water←Earliest life(-4100)←LHB meteorites←Earliest oxygen←Atmospheric oxygen←Oxygen Crisis←Earliest sexual reproduction←Cambrian explosion←Earliest humansPhanrzcProterozoicArcheanHadeanAxis scale: millions of years.also see Modèle:Human timeline and Modèle:Nature timeline Biodiversity, a contraction of "biological diversity," generally refers to the variety and variability of life on Earth. One of the most widely used definitions defines it in terms of the variability within species, between species and between ecosystems. It is a measure of the variety of organisms present in different ecosystems. This can refer to genetic variation, ecosystem variation, or species variation (number of species) within an area, biome, or planet. Terrestrial biodiversity tends to be greater near the equator, which seems to be the result of the warm climate and high primary productivity. Biodiversity is not distributed evenly on Earth. It is richest in the tropics. Marine biodiversity tends to be highest 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. The number and variety of plants, animals and other organisms that exist is known as biodiversity. It is an essential component of nature and it ensures the survival of human species by providing food, fuel, shelter, medicines and other resources to mankind. The richness of biodiversity depends on the climatic conditions and area of the region. All species of plants taken together are known as flora and about 70,000 species of plants are known to date. All species of animals taken together are known as fauna which includes birds, mammals, fish, reptiles, insects, crustaceans, molluscs, etc. Rapid environmental changes typically cause mass extinctions. More than 99 percent of all species, amounting to over five billion species, that ever lived on Earth 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. More recently, in May 2016, scientists reported that 1 trillion species are estimated to be on Earth currently with only one-thousandth of one percent 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 4 TtC (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 old. 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 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, the reduction is caused primarily by human impacts, particularly habitat destruction. Conversely, biodiversity impacts human health in a number of ways, both positively and negatively. The United Nations designated 2011–2020 as the United Nations Decade on Biodiversity. |
External references (Wikipedia)
Médias référencés
Objet de commun (14)
- A Community Charter (Falkirk, UK) (UK)
- Charte de végétalisation de l’espace public parisien (France)
- Charte des mangroves d'Afrique de l'Ouest (Afrique de l'Ouest)
- Cultures en transition (France, UK, Cuba,, 01:05:46)
- Isabella Lövin - Le pillage des mers : une autre tragédie des communs. (Suède, 09:30)
- La guerre des graines (France)
- Les biens communs, modèle de gestion des ressources naturelles (France)
- Les graines de la liberté (00:30:00)
- Menaces sur la foret francaise (France, 00:52:00)
- Remuer la terre, c’est remuer les consciences (France, 00:37:58)
- Sciences et démocratie : La leçon du Tapajos (Brésil, 00:19:40)
- Seeds of Freedom (00:30:00)
- Seeing the Forest (USA, 00:31:14)
- Theory and Practice in the Management of Natural Commons (00:30:14)
Enjeu (5)
- Charte des Garrigues (France)
- Greater London National Park City Proposal (England)
- Pat Mooney: Rio +20, les principaux champs de bataille en émergence. (Canada, 00:07:36)
- Permis de végétaliser (Paris) (France)
- Permis de végétaliser Paris 2015 (autorisation d'occupation temporaire du domaine public) (France)
Sources
Wikidata : Q47041
DBpedia FR : Biodiversité
DBpedia EN : Biodiversity
P2P Foundation : Biodiversity
Digital Library of the Commons : Biodiversity
Autres langues (Wikipedia)
Biodiversiteit (afwiki)
Biodiversidat (anwiki)
تنوع حيوي (arwiki)
Biodiversidá (astwiki)
জৈৱ বৈচিত্ৰ্য (aswiki)
Bioloji müxtəliflik (azwiki)
Біялагічная разнастайнасць (bewiki)
Биоразнообразие (bgwiki)
जैवविविधता (bhwiki)
জীববৈচিত্র্য (bnwiki)
Biološka raznolikost (bswiki)
Biodiversitat (cawiki)
Biologická diverzita (cswiki)
Bioamrywiaeth (cywiki)
Biodiversitet (dawiki)
Biodiversität (dewiki)
जैविक विविधता (dtywiki)
Βιοποικιλότητα (elwiki)
Biodiversity (enwiki)
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Elurikkus (etwiki)
Elurikkus (etwikiquote)
Biodibertsitate (euwiki)
تنوع زیستی (fawiki)
Biodiversiteetti (fiwiki)
Biodiversité (frwiki)
Bithéagsúlacht (gawiki)
Biodiversidade (glwiki)
Tekove'etaita (gnwiki)
מגוון ביולוגי (hewiki)
जैव विविधता (hiwiki)
Bioraznolikost (hrwiki)
Biyodivèsite (htwiki)
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Կենսաբազմազանություն (hywiki)
Biodiversitate (iawiki)
Keanekaragaman hayati (idwiki)
Biodiverseso (iowiki)
Líffræðilegur fjölbreytileiki (iswiki)
Biodiversità (itwiki)
Biodiversità (itwikiquote)
Biodiversità (itwikiversity)
生物多様性 (jawiki)
Tuggtudert (kabwiki)
ბიომრავალფეროვნება (kawiki)
Биологиялық әралуандылық (kkwiki)
ಜೀವವೈವಿಧ್ಯ (knwiki)
생물 다양성 (kowiki)
Zorbûna jiyanî (kuwiki)
Diversitas biologica (lawiki)
Obulamu obw'Enjawulo (Biodiversity) (lgwiki)
Biodiversiteit (liwiki)
Biologinė įvairovė (ltwiki)
Bioloģiskā daudzveidība (lvwiki)
Биоразновидност (mkwiki)
ജൈവവൈവിധ്യം (mlwiki)
जैवविविधता (mrwiki)
Biokepelbagaian (mswiki)
Bijodiversità (mtwiki)
जैविक विविधता (newiki)
Biodiversiteit (nlwiki)
Biologisk mangfald (nnwiki)
Biologisk mangfold (nowiki)
Biodiversitat (ocwiki)
ਜੀਵ ਵੰਨ-ਸੁਵੰਨਤਾ (pawiki)
Różnorodność biologiczna (plwiki)
دژوندبڼو ډولونه (pswiki)
Biodiversidade (ptwiki)
Biodiversitad (rmwiki)
Biodiversitate (rowiki)
Биоразнообразие (ruwiki)
Категория:Биоразнообразие (ruwikinews)
Biodiversity (scowiki)
Bioraznolikost (shwiki)
Biodiversity (simplewiki)
ජෛවවිවිධත්වය (siwiki)
Biodiverzita (skwiki)
Biotska raznovrstnost (slwiki)
Bioshumëllojshmëria (sqwiki)
Biološka raznovrsnost (srwiki)
Biologisk mångfald (svwiki)
Biologisk mångfald (svwikinews)
உயிரியற் பல்வகைமை (tawiki)
ความหลากหลายทางชีวภาพ (thwiki)
Biodaivesiti (tpiwiki)
Biyoçeşitlilik (trwiki)
Биотөрлелек (ttwiki)
Біорізноманіття (ukwiki)
حیاتی تنوع (urwiki)
Đa dạng sinh học (viwiki)
Biyodibersidad (warwiki)
生物多样性 (wuuwiki)
生物多樣性 (zh_yuewiki)
生物多樣性 (zhwiki)
