The Global 200 : a representation Approach to Conserving the Earth’s Distinctive Ecoregions
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- Australasia
- C entral Sulawesi Lakes [188]
- Indo-Malayan
- Neotropical
Small LakesGenerally characterized by less surface area and shallower waters than Large Lakes, Small Lakes tend to support fewer taxa. However, many of these areas support levels of endemism that are extraordinarily high for the size of the systems. Afrotropical
ameroon Crater Lakes [186] – Cameroon Geographic Location: Western Africa Biodiversity Features: The crater lakes located in this ecoregion include Barombi Mbo, Bermin, Dissoni (Soden), Benakouma, Kotto, and Mboandong. The lakes formed in the hollow depressions of the craters left by former volcanoes that stretch inland from the sea. The ancient nature of these lakes together with their isolation has led to an extremely high level of endemism. Over 75% of the fish species and approximately one-third of the aquatic insects found in the crater lakes are endemic. Selected Species: The fish fauna is dominated by cichlids, of which there are four endemic genera (Konia, Myaka, Pungu and Stomatepia). In addition to endemic fish, there are undescribed endemic cardinid shrimps in Lake Dissoni. The fish-eating colubrid snake, Afronatrix anoscopus, lives in Lake Bermin. The aquatic fauna of Lake Benakouma remains largely unexplored. General Threats: Threats vary from lake to lake. Lake Barombi Mbo is an example of a lake under high fishing pressure and suffering from the effects of deforestation, overfishing, and excessive water extraction. Others, like Lake Bermin, remain relatively undisturbed. There is an urgent need to protect Barombi Mbo due to the many threats it faces, as well as to guard against the introduction of exotic species. Australasia
akes Kutubu and Sentani [187] – Indonesia, Papua New Guinea Geographic Location: Southeast Asia Biodiversity Features: New Guinea's relatively small Lake Kutubu contains 11 endemic fish species, a phenomenon rarely seen in tropical lakes outside of those in the Rift Valley of Africa. Lake Sentani contains two endemic fish. Invertebrates are poorly known for this ecoregion. Distinctive island biotas and highly endemic fish faunas, unusual for small tropical lakes Selected Species: Endemic fish species include Kutubu tandan (Oloplotosus torobo), Lake Kutubu rainbowfish (Melanotaenia lacustris), Kutubu hardyhead (Craterocephalus lacustris), Adamson’s grunter (Hephaestus adamsoni), Lake Kutubu mogurnda (Mogurnda kutubuensis), blotched and variegated mogurndas (M. spilota and M. variegata), and Sentani rainbowfish (Chilatherina sentaniensis). General Threats: This ecoregion is located within one of the least populated areas of Papua New Guinea. Lake Kutubu is threatened by overfishing and oil developments nearby, with associated road-building activities and potential for oil spills. Introduced fish species could be very harmful to the endemic species found in these lakes.
entral Sulawesi Lakes [188] – Indonesia Geographic Location: Indonesia Biodiversity Features: Many endemic species live in these old, isolated lakes and several groups of fishes, crabs, prawns, and molluscs are the product of species radiations. Approximately sixty endemic molluscs, over twenty-five endemic fish, ten shrimps, and three crabs are known from the central Sulawesi lakes. Species radiations have occurred in the following fish families: the sailfin silversides (Telmatherinidae), halfbeaks (Hemiramphidae), and ricefishes (Adrianichthydae). The Matano-Towuti lake system alone harbors twenty fish, twelve molluscs, one endemic snake, and seven plants. Lake Matano and the nearby lakes also support many rare aquatic plants, including floating ferns. distinctive and highly endemic biota of tropical island lakes, SPECIES RADIATIONS Selected Species: Distinctive species include Matano ricefish (Oryzias matanensis), Matanna water snake (Enhydris matannensis), and an endemic goby (Glossogobius matanensis). General Threats: Potential threats to the freshwater fauna include lakeshore nickel mining, commercial fishery development, species introductions, and the effects of human population growth. Indo-Malayan
hilippines reshwater [189] – Philippines Geographic Location: Southeast Asia
Biodiversity Features: The streams and lakes of this island ecoregion support high numbers of endemic species, particularly of fish. Historically, this ecoregion was home to 30 endemic fish species, including a radiation of 18 endemic cyprinid species in Lake Lanao. Many catadromous fish species from marine families occur in freshwaters and migrate to the ocean to spawn. There is also a highly endemic crab fauna on this island, as well as endemic copepods associated with Lake Lanao. high levels of endemism and one of THE most significant radiations of tropical lake fishes IN ASIA Selected Species: Endemic species such as Puntius lindug, P. baoulan, and P. tumba have been driven to the brink of extinction by introduced species. This ecoregion also supports disjunct populations of the highly endangered Philippine crocodile (Crocodylus mindorensis). General Threats: Many of the Philippines’ endemic species face extinction from the establishment of exotic species. For example, the introduction of common carp (Cyprinus carpio) and tank goby (Glossogobius giuris) have caused the near-extinction of the Lake Lanao species flock. Logging and subsequent erosion is a serious threat to the water quality of the ecoregion’s freshwater habitats, as are mining and agriculture to a lesser extent.
ake Inle [190] – Myanmar Geographic Location: Southern Asia Biodiversity Features: This relatively shallow mountain lake at 900-m elevation supports nine endemic fish species in three endemic genera. Over twenty species of gastropods, of which one-third may be endemic, are found in the lake. Unusual levels of endemism for lake fauna of indochina Selected Species: Endemic or characteristic fish species include the Inle swamp eel (Chaudhuria caudata) and Inle barb (Sawbwa resplendens). General Threats: The lake has been drastically modified through land reclamation. Floating gardens have been constructed within the lake and in many places the lake is merely a maze of canals between these plots. Runoff of pesticides and fertilizer from these lands pollute the lake, as does sedimentation from cattle grazing and runoff of sewage from surrounding lands. unnan Lakes and Streams [191] – China Geographic Location: Southern Asia Biodiversity Features: Several large, freshwater lakes are situated on the Yunnan Plateau at elevations of 1800-2000 m. These tend to occupy deep grabens, trenches created by faulting of adjacent mountains, but the lakes themselves are not necessarily deep as they have filled partially with alluvial sediments. These plateau lakes support some of the most diverse freshwater ecosystems in the entire country. Both Dianchi and Er Hai, for example, contain rich fish faunas. Despite their location in separate river basins (Yangtze and Mekong, respectively), taxonomic similarities of these lakes exceed differences. Dianchi historically supported twenty-five native fish species, of which eleven are endemic (all but two are apparently extinct), and Er Hai supported seventeen native fish species, of which nine are endemic. Other endemics in this ecoregion include aquatic plants, invertebrates, and amphibians. This region’s karstic geology has also produced numerous caves, in which at least fourteen cave fishes live. Unusual endemism for subtropical lakeS in southern asia Selected Species: Numerous endemic fish species in the genera Cyprinus, Schizothorax, Anabarilius, and Yunnanilus occur in this ecoregion. Several lakes historically contained faunas with over half their fish species endemic. Exact numbers of species and endemics are unknown. General Threats: Lake shores have been deforested for centuries and are today encircled by intensive rice agriculture. Increased inputs of silt and fertilizer from the rice fields, and human and industrial waste from nearby areas, all affect the quality of the water. Moreover, many of the lakes support aquaculture and fisheries that may not be sustainable under the force of today’s vigorous economy. Lake Dianchi, which has lost most of its endemic fish species, is an example of a lake that has suffered from sewage, industrial pollutants, and introduced species. These lakes are found in one of only two remaining subtropical forests in China on the Yunnan-Guizhou Plateau, but deforestation along the lakes and streams has caused soil erosion and destroyed habitat. Pollution is also a significant threat. Neotropical
exican Highland Lakes [192] – Mexico Geographic Location: Central America Biodiversity Features: A number of endorheic lakes, thermal springs and streams occur in this ecoregion. These habitats are characterized by unusual amphibian and invertebrate species, as well as fish species radiations in several lakes. In particular, Lake Chapala and the Rio Lerma support fish faunas in which over half of the species are endemic. In addition, the Aguascalientes warm-water aquifer and its subterranean biota underlie portions of the ecoregion. Neotropical lakes AND STREAMS with unusual HIGH LEVELS OF ENDEMISM AMONG fish species Selected Species: Species include numerous endemic livebearers (family Poecillidae), splitfins (Goodeidae), silversides (Atherinidae), pupfishes (Cyprinodontidae), cichlids (Cichlidae), and characids (Characiformes). Among the numerous fish species whose distributions are restricted to this ecoregion are Mexican brook lamprey (Lampetra geminis), Lerma chub (Algansea barbata), leopard splitfin (Xenotaenia resolanae), bagre catfish (Ictalurus dugesii), charal (Chirostoma chapalae), Potosi pupfish (Cyprinodon alvarezi), flatjaw minnow (Dionda mandibularis), black lyre (Poecilia latipinna), graceful priapella (Priapella bonita), Chapala chub (Algansea popoche), scowling silverside (Chirostoma aculeatum), and largetooth silverside (C. arge). Endemic amphibians include Rana megapoda, R. montezumae and a near-endemic salamander genus, Ryacosiredon. Freshwater habitats also support a distinctive and endemic invertebrate fauna, including La Medialuna crayfish (Procambarus roberti), La Medialuna shrimp (Palaemonetes lindsayi), and the crayfish’s obligatory parasite, La Medialuna ostracod (Ankylocythere barbouri). General Threats: The freshwater species of this largely xeric region must compete with agriculture and burgeoning human populations for the limited water supply. Of great concern is the tapping of aquifers, which threatens the survival of several spring fish. Water withdrawals and diversions for agriculture, combined with pollution from industrial waste, agriculture, and urbanization threaten the quality and quantity of water available to the freshwater biota of this ecoregion. Invasive aquatic plants (e.g., water hyacinth, Eichhornia crassipes, and introduced nonnative fish like blue tilapia, Oreochromis aureus) could potentially cause the decline of native species. Directory: downloads downloads -> Northern England’s set-jetting locations downloads -> Dynatest 3031 lwd light Weight Deflectometer downloads -> Forth coming competitive exams downloads -> Brush High School Morning Announcements Friday, September 05, 2014 all school downloads -> Year 9 The Arts — Music downloads -> Years 7 and 8 standard elaborations — Australian Curriculum: Music draft downloads -> Chris Young sets 2016 “I’m Comin’ Over” Tour headlining dates downloads -> Slavery and Abolition: the Plymouth Connection Introduction downloads -> Summer Assignment Download 2.75 Mb. Share with your friends:
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