Ecoregions in the Philippines
ThePhilippinearchipelagois one of the world's great reservoirs ofbiodiversityandendemism.The archipelago includes over 7000 islands, and a total land area of 300,780 km2.
The Philippines was never connected to mainlandAsiavialand bridges,[dubious–discuss]so the flora and fauna of the islands had to cross ocean straits to reach the Philippines. The Philippines is part of theIndomalayan realm,and its flora and fauna is mostly derived from tropical Asia.Botanically,the Philippines are part ofMalesia,afloristic provincethat includes theMalay Peninsula,Indonesia,andNew Guinea.Most of the Malesian flora is derived from tropical Asia, including thedipterocarps,which are the characteristic tree of the Philippine forests. Elements of theAntarctic flora,which originated in the ancientsouthern hemispheresupercontinent ofGondwana,are also present, including ancient conifers likepodocarps(Podocarpus,Nageia,Sundacarpus) andaraucarias(Agathis).
Theecoregionsof the Philippines are defined primarily by the sea levels during the Ice Ages, which were 120 meters lower than at present, as billions of gallons of water were locked away in huge continental ice sheets. This drop in sea level connected many presently separate islands into larger islands, which allowed for exchanges of flora and fauna:
- Greater LuzonincludedLuzon,Catanduanes,Marinduque,Polillo,and several small islands.
- Greater MindanaoincludedMindanao,Basilan,Bohol,Leyte,Samar,and adjacent small islands.
- Greater PalawanincludedPalawan,Balabac, Busuanga, Culion, Cuyo, and adjacent small islands.
- Greater Negros–PanayincludedNegros,Panay,Cebu,andMasbate.
- Greater Suluincluded the most of theSulu Archipelago,fromTawi TawitoJolo.
These formerly-linked islands each constitute a separate ecoregion, as doesMindoro,which remained separate from the rest, along with a few smaller islands, notably Camiguin, Sibuyan, and Siquijor.
Each group of islands that were linked by land bridges in the ice ages also constitutes a separate faunal region. The lack of a land bridge to the Asian continent prevented most of the Asianmegafauna,includingelephants,rhinoceros,tapirs,tigers,leopards,andgibbons,from reaching the Philippines, although they do inhabit the adjacentIndonesianislands ofSundaland,which were formerly linked to the Asian continent by lowered sea levels.
The other main factor that defines the Philippine ecoregions is elevation; the highmountains of Luzonand Mindanao host distinct montane rain forest ecoregions. The mountains of Luzon are also home to theLuzon tropical pine forests.
Terrestrial ecoregions[edit]
by major habitat type[1]
Tropical and subtropical moist broadleaf forests
- Greater Negros-Panay rain forests
- Luzon montane rain forests
- Luzon rain forests
- Mindanao montane rain forests
- Mindanao-Eastern Visayas rain forests
- Mindoro rain forests
- Palawan rain forests
- South China Sea Islands(disputed betweenChina,Malaysia,Philippines,Taiwan,Vietnam)
- Sulu Archipelago rain forests
Tropical and subtropical coniferous forests
Freshwater ecoregions[edit]
Source:[2]
- Northern Philippine Islands
- Palawan – Busuanga – Mindoro
- Mindanao
- Lake Lanao
Marine ecoregions[edit]
by marine province[3]
Central Indo-Pacific[edit]
- South China Sea
- Coral Triangle
- Western Coral Triangle
- Palawan/North Borneo
- Eastern Philippines
- Sulawesi Sea/Makassar Strait
- Western Coral Triangle
See also[edit]
References[edit]
- ^Wikramanayake, Eric; Eric Dinerstein; Colby J. Loucks; et al. (2002).Terrestrial Ecoregions of the Indo-Pacific: a Conservation Assessment.Washington, DC: Island Press.
- ^Spalding, Mark D., Helen E. Fox, Gerald R. Allen, Nick Davidsonet al."Marine Ecoregions of the World: A Bioregionalization of Coastal and Shelf Areas".BioscienceVol. 57 No. 7, July/August 2007, pp. 573–583.
- ^Spalding, Mark D., Helen E. Fox, Gerald R. Allen, Nick Davidsonet al."Marine Ecoregions of the World: A Bioregionalization of Coastal and Shelf Areas".BioscienceVol. 57 No. 7, July/August 2007, pp. 573–583.[1]