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67-663: The Cerrado ( Portuguese pronunciation: [seˈʁadu] ) is a vast ecoregion of tropical savanna in eastern Brazil , being present in the states of Goiás , Mato Grosso do Sul , Mato Grosso , Tocantins , Maranhão , Piauí , Bahia , Minas Gerais , São Paulo , Paraná and the Federal District . The core areas of the Cerrado biome are the Brazilian highlands – the Planalto . The main habitat types of

134-406: A diverse local population that relies heavily on the resources of their environment. Until the mid-1960s, agricultural activities in the Cerrado were very limited, since natural cerrado soils are not fertile enough for crop production, directed mainly at the extensive production of beef cattle for subsistence of the local market. After this period, however, the urban and industrial development of

201-415: A given ecoregion are more similar to each other than to those of surrounding ecoregions and together form a conservation unit. Freshwater systems include rivers , streams , lakes , and wetlands . Freshwater ecoregions are distinct from terrestrial ecoregions, which identify biotic communities of the land, and marine ecoregions, which are biotic communities of the oceans. A map of Freshwater Ecoregions of

268-469: A holistic, "weight-of-evidence" approach where the importance of various factors may vary. An example of the algorithmic approach is Robert Bailey 's work for the U.S. Forest Service, which uses a hierarchical classification that first divides land areas into very large regions based on climatic factors, and subdivides these regions, based first on dominant potential vegetation, and then by geomorphology and soil characteristics. The weight-of-evidence approach

335-409: A pale yellow to brown color, developed in midlands in processes still under investigation; as are those forming lowland soils resembling European brown soils . In Australia vast areas formerly covered in rainforest have become so dry that oxisols have formed a hard ironstone cover upon which only skeletal soils can form. Fossil oxisols are known from the first appearance of free oxygen in

402-517: A set of ecoregions identified by WWF whose conservation would achieve the goal of saving a broad diversity of the Earth's ecosystems, includes a number of areas highlighted for their freshwater biodiversity values. The Global 200 preceded Freshwater Ecoregions of the World and incorporated information from regional freshwater ecoregional assessments that had been completed at that time. Sources related to

469-596: A significant increase in agricultural and cattle production. On the other hand, the urban pressure and the rapid establishment of agricultural activities in the region have been rapidly reducing the biodiversity of the ecosystems, and the population in the Cerrado region more than doubled from 1970 to 2010, going from 35.8 to 76 million. The Cerrado was thought challenging for agriculture until researchers at Brazil's agricultural and livestock research agency, Embrapa , discovered that it could be made fit for industrial crops by appropriate additions of phosphorus and lime. In

536-432: A temperate crop, and currently, Brazil is the world's main soyabeans exporter due to the boom in animal feed production caused by the global rise in meat demand. Today the Cerrado region provides more than 70% of the beef cattle production in the country, being also a major production center of grains, mainly soya, beans, maize, and rice. Large extensions of the Cerrado are also used for the production of cellulose pulp for

603-407: A web application developed by Resolve and Google Earth Engine. An ecoregion is a "recurring pattern of ecosystems associated with characteristic combinations of soil and landform that characterise that region". Omernik (2004) elaborates on this by defining ecoregions as: "areas within which there is spatial coincidence in characteristics of geographical phenomena associated with differences in

670-419: Is a relatively high diversity of snakes in the Cerrado (22–61 species, depending on site) with Colubridae being the richest family. The open nature of the cerrado vegetation most likely contributes to the high diversity of snakes. Information about Cerrado amphibians is extremely limited, although the Cerrado probably has a unique assemblage of species with some endemic to the region. Most birds found in

737-722: Is an area of vegetation known as the wet campo with distinct up- and downslope borders where tree growth is inhibited due to wide seasonal fluctuations in the water table. The savanna portion of the Cerrado is heterogeneous in terms of canopy cover. Goodland (1971) divided the Cerrado into four categories ranging from least to most canopy cover: campo sujo ( herbaceous layer with occasional small trees about 3 m tall), campo cerrado (slightly higher density of trees about 4 m tall on average), cerrado sensu stricto (orchard-like vegetation with trees about 6 m high) and cerradão (canopy cover near 50% with general height 9 m). Probably around 800 species of trees are found in

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804-426: Is analogous to that used for terrestrial ecoregions. Major habitat types are identified: polar, temperate shelves and seas, temperate upwelling, tropical upwelling, tropical coral, pelagic (trades and westerlies), abyssal, and hadal (ocean trench). These correspond to the terrestrial biomes . The Global 200 classification of marine ecoregions is not developed to the same level of detail and comprehensiveness as that of

871-729: Is composed mainly of the Poaceae , Cyperaceae , Leguminosae , Compositae , Myrtaceae and Rubiaceae . Much of the vegetation in the gallery forests is similar to nearby rainforest; however, there are some endemic species found only in the Cerrado gallery forests. Soil fertility, fire regime and hydrology are thought to be most influential in determining Cerrado vegetation. Cerrado soils are always well-drained and most are oxisols with low pH and low calcium and magnesium. The amount of potassium, nitrogen and phosphorus has been found to be positively correlated with tree trunk basal area in Cerrado habitats. Much as in other grasslands and savannas, fire

938-622: Is exemplified by James Omernik's work for the United States Environmental Protection Agency , subsequently adopted (with modification) for North America by the Commission for Environmental Cooperation . The intended purpose of ecoregion delineation may affect the method used. For example, the WWF ecoregions were developed to aid in biodiversity conservation planning, and place a greater emphasis than

1005-407: Is generally thought to be relatively low in the Cerrado compared to other areas like caatinga or lowland rainforest, although one recent study found 57 species in one cerrado area with the high diversity driven by the availability of open habitat. Ameiva ameiva is among the largest lizards found in the Cerrado and is the most important lizard predator where it is found in the Cerrado. There

1072-529: Is important in maintaining and shaping the Cerrado's landscape; many plants in the Cerrado are fire-adapted, exhibiting characters like thick corky bark to withstand the heat. Cerrado vegetation is believed to be ancient, stretching back perhaps as far in a prototypic form as the Cretaceous , before Africa and South America separated. A dynamic expansion and contraction between cerrado and Amazonian rainforest has probably occurred historically, with expansion of

1139-526: Is optimal for all taxa. Ecoregions reflect the best compromise for as many taxa as possible. Secondly, ecoregion boundaries rarely form abrupt edges; rather, ecotones and mosaic habitats bound them. Thirdly, most ecoregions contain habitats that differ from their assigned biome . Biogeographic provinces may originate due to various barriers, including physical (plate tectonics, topographic highs), climatic (latitudinal variation, seasonal range) and ocean chemical related (salinity, oxygen levels). The history of

1206-445: Is privately owned. Vast amounts of research have shown that the Cerrado is one of the richest of all tropical savanna regions and has high levels of endemism . Characterizing it by its enormous ranges of plant and animal biodiversity, World Wide Fund for Nature named the Cerrado the biologically richest savanna in the world, with about 10,000 plant species and 10 endemic bird species. There are nearly 200 species of mammal in

1273-901: The Brazilian Constitution as a National Heritage. It is also home to the Guarani Aquifer , stores the largest fresh water underground reservoirs in South America, and supplies water to a third of the Amazon river and the largest basins in the continent. Brazilian agriculturalists and ministers regard it as having no conservation value, and the government has protected merely 1.5% of the Cerrado biome in Federal Reserves. By 1994, an estimated 695,000 km of cerrado (representing 35% of its area) had been converted to 'anthropic [sic] landscape'. In total, 37.3% of

1340-608: The Himalayas and the Sahara . The boundaries of ecoregions are often not as decisive or well recognized, and are subject to greater disagreement. Ecoregions are classified by biome type, which are the major global plant communities determined by rainfall and climate. Forests, grasslands (including savanna and shrubland), and deserts (including xeric shrublands ) are distinguished by climate ( tropical and subtropical vs. temperate and boreal climates) and, for forests, by whether

1407-508: The Xingu and Tapajós . During the last four decades, the Cerrado’s river basins have been highly impacted by extreme deforestation, expansion of the agricultural and cattle ranching frontier, construction of dams, and extraction of water for irrigation. The Cerrado is the second largest biome in South America and the most biodiverse savanna in the world. However, it is not currently recognized by

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1474-465: The atmosphere about 2,200 million years ago. In warm periods like the Mesozoic and Paleocene , oxisols extended to areas that now have quite cool climates, extending well into North America and Europe . It is believed oxisols became vegetated later than ultisols or alfisols , probably because vegetation took a long time to adapt to the infertility of oxisols. Scientists originally thought that

1541-450: The "ecoregion" as a unit of analysis. The " Global 200 " is the list of ecoregions identified by WWF as priorities for conservation . Terrestrial ecoregions are land ecoregions, as distinct from freshwater and marine ecoregions. In this context, terrestrial is used to mean "of land" (soil and rock), rather than the more general sense "of Earth " (which includes land and oceans). WWF (World Wildlife Fund) ecologists currently divide

1608-787: The Biodiversity of the Cerrado Biome, with UK Overseas Development Administration funding. Its aim is to survey the floristic patterns of Cerrado vegetation and to discover representative areas and biodiversity "hot-spots". A 2017 assessment found that 433,581 km, or 23%, of the ecoregion is in protected areas. Protected areas in Brazil include: as well as Noel Kempff Mercado National Park in Bolivia. Ecoregion Three caveats are appropriate for all bio-geographic mapping approaches. Firstly, no single bio-geographic framework

1675-625: The Brazilian cerrados was provided by Danish botanist Eugenius Warming (1892) in the book Lagoa Santa, in which he describes the main features of the cerrado vegetation in the state of Minas Gerais . Taking advantage of the sprouting of the herbaceous stratum that follows a burning in the Cerrado, the aboriginal inhabitants of these regions learned to use the fire as a tool, to increase the fodder to offer to their domesticated animals. Xavantes , Tapuias  [ pt ] , Karajás , Avá- Canoeiros , Krahôs , Xerentes , Xacriabás were some of

1742-461: The Cerrado and play an important role in consuming and decomposing organic matter, as well as constituting an important food source to many other animal species. The highest diversity of galling insects (insects that build galls ) in the world is also found in the Cerrado, with the most species (46) found at the base of the Serra do Cipó in southeast Brazil. The first detailed European account of

1809-419: The Cerrado are relatively understudied. A yearlong survey of the Cerrado at one reserve in Brazil found that the orders Coleoptera , Hymenoptera , Diptera and Isoptera accounted for 89.5% of all captures. The Cerrado also supports a high density (up to 4000 per hectare) of the nests of leaf cutter ants ( saúvas ), which are also very diverse. Along with termites, leaf cutter ants are the primary herbivores of

1876-499: The Cerrado breed there although there are some Austral migrants (breed in temperate South America and winter in the Amazon basin) and Nearctic migrants (breed in temperate North America and winter in the Neotropics) that pass through. Most breeding birds in the Cerrado are found in more closed canopy areas like gallery forests although 27% of the birds breed only in open habitats and 21% breed in either open or closed habitats. Many of

1943-476: The Cerrado consist of forest savanna, wooded savanna, park savanna and gramineous -woody savanna. The Cerrado also includes savanna wetlands and gallery forests . The second largest of Brazil's major habitat types , after the Amazonian rainforest , the Cerrado accounts for a full 21 percent of the country's land area (extending marginally into Paraguay and Bolivia). About 75% of the Cerrado’s 2 million km

2010-542: The Cerrado during glacial periods like the Pleistocene . These processes and the resulting fragmentation in multiple refugia have probably contributed to the high species richness both of the Cerrado and of the Amazonian rainforest. The Cerrado has a high diversity of vertebrates, with 150 amphibian species, 120 reptile species, 837 bird species, and 161 mammal species recorded. Lizard diversity

2077-442: The Cerrado has already been totally converted to human use, while an additional 41.4% is used for pasture and charcoal production. The gallery forests in the region have been among the most heavily affected. It is estimated that only about 432,814 km, or 21.3% of the original vegetation, remains intact today. During the last 25 years this biome has been increasingly threatened by industrial monoculture farming, particularly soybeans,

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2144-470: The Cerrado, they now are receiving some charcoal from the eucalyptus plantations and these efforts are growing. The Cerrado biome is strategic for the water resources of Brazil. The biome contains the headwaters and the largest portion of South American watersheds (the Paraná-Paraguay, Araguaia-Tocantins, and São Francisco river basins) and the upper catchments of large Amazon tributaries, such as

2211-450: The Cerrado, though only 14 are endemic. The large fraction of private ownership makes protection difficult though. The Cerrado's climate is typical of the wetter savanna regions of the world, with a semi-humid tropical climate . The Cerrado is limited to two dominant seasons throughout the year: Wet and dry. Annual temperatures for the Cerrado average between 22 and 27 °C and average precipitation between 80–200 cm for over 90% of

2278-606: The Cerrado. Among the most diverse families of trees in the Cerrado are the Leguminosae  (153 spp.), Malpighiaceae  (46), Myrtaceae  (43), Melastomataceae  (32), and Rubiaceae  (30). Much of the Cerrado is dominated by the Vochysiaceae (23 species in the Cerrado) due to the abundance of three species in the genus Qualea . The herbaceous layer usually reaches about 60 cm in height and

2345-558: The Earth. The use of the term ecoregion is an outgrowth of a surge of interest in ecosystems and their functioning. In particular, there is awareness of issues relating to spatial scale in the study and management of landscapes . It is widely recognized that interlinked ecosystems combine to form a whole that is "greater than the sum of its parts". There are many attempts to respond to ecosystems in an integrated way to achieve "multi-functional" landscapes, and various interest groups from agricultural researchers to conservationists are using

2412-552: The Omernik or Bailey systems on floral and faunal differences between regions. The WWF classification defines an ecoregion as: A large area of land or water that contains a geographically distinct assemblage of natural communities that: According to WWF, the boundaries of an ecoregion approximate the original extent of the natural communities prior to any major recent disruptions or changes. WWF has identified 867 terrestrial ecoregions, and approximately 450 freshwater ecoregions across

2479-550: The Southeast Region has forced agriculture to the Central-West Region. The transfer of the country's capital to Brasília has been another focus of attraction of population to the central region: From 1975 until the beginning of the 1980s, many governmental subsidy programs were launched to promote agriculture, with the intent of stimulating the development of the Cerrado region. As a result, there has been

2546-783: The WWC scheme: Others: Oxisol Oxisols are a soil order in USDA soil taxonomy , best known for their occurrence in tropical rain forest within 25 degrees north and south of the Equator . In the World Reference Base for Soil Resources (WRB), they belong mainly to the ferralsols , but some are plinthosols or nitisols . Some oxisols have been previously classified as laterite soils. The main processes of soil formation of oxisols are weathering , humification and pedoturbation due to animals. These processes produce

2613-571: The WWF concept prioritizes biogeography, that is, the distribution of distinct species assemblages. In 2017, an updated terrestrial ecoregions dataset was released in the paper "An Ecoregion-Based Approach to Protecting Half the Terrestrial Realm" led by E. Dinerstein with 48 co-authors. Using recent advances in satellite imagery the ecoregion perimeters were refined and the total number reduced to 846 (and later 844), which can be explored on

2680-523: The World (TEOW), led by D. Olsen, E. Dinerstein, E. Wikramanayake, and N. Burgess. While the two approaches are related, the Bailey ecoregions (nested in four levels) give more importance to ecological criteria and climate zones, while the WWF ecoregions give more importance to biogeography, that is, the distribution of distinct species assemblages. The TEOW framework originally delineated 867 terrestrial ecoregions nested into 14 major biomes, contained with

2747-783: The World, released in 2008, has 426 ecoregions covering virtually the entire non-marine surface of the earth. World Wildlife Fund (WWF) identifies twelve major habitat types of freshwater ecoregions: Large lakes, large river deltas, polar freshwaters, montane freshwaters, temperate coastal rivers, temperate floodplain rivers and wetlands, temperate upland rivers, tropical and subtropical coastal rivers, tropical and subtropical floodplain rivers and wetlands, tropical and subtropical upland rivers, xeric freshwaters and endorheic basins, and oceanic islands. The freshwater major habitat types reflect groupings of ecoregions with similar biological, chemical, and physical characteristics and are roughly equivalent to biomes for terrestrial systems. The Global 200 ,

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2814-411: The area. This ecoregion has a very strong dry season during the southern winter (approx. April–September). The Cerrado is characterized by unique vegetation types. It is composed of a shifting mosaic of habitats, with the savanna-like cerrado itself on well-drained areas between strips of gallery forest (closed canopy tall forest) which occur along streams. Between the cerrado and the gallery forest

2881-480: The authors was to support global biodiversity conservation by providing a "fourfold increase in resolution over that of the 198 biotic provinces of Dasmann (1974) and the 193 units of Udvardy (1975)." In 2007, a comparable set of Marine Ecoregions of the World (MEOW) was published, led by M. Spalding, and in 2008 a set of Freshwater Ecoregions of the World (FEOW) was published, led by R. Abell. Bailey's ecoregion concept prioritizes ecological criteria and climate, while

2948-516: The birds in the Cerrado, especially those found in closed forest, are related to species from the Atlantic rainforest and also the Amazon rainforest. The crowned solitary eagle , hyacinth macaw , toco toucan , buff-necked ibis , dwarf tinamou , and Brazilian merganser are examples of birds found in the Cerrado. Gallery forests serve as primary habitat for most of the mammals in the Cerrado, having more water, being protected from fires that sweep

3015-677: The broad latitudinal divisions of polar, temperate, and tropical seas, with subdivisions based on ocean basins (except for the southern hemisphere temperate oceans, which are based on continents). Major marine biogeographic realms, analogous to the eight terrestrial biogeographic realms , represent large regions of the ocean basins: Arctic , Temperate Northern Atlantic , Temperate Northern Pacific , Tropical Atlantic , Western Indo-Pacific , Central Indo-Pacific , Eastern Indo-Pacific , Tropical Eastern Pacific , Temperate South America , Temperate Southern Africa , Temperate Australasia , and Southern Ocean . A similar system of identifying areas of

3082-469: The characteristic soil profile . They are defined as soils containing at all depths no more than ten percent weatherable minerals , and low cation exchange capacity . Oxisols are always a red or yellowish color, due to the high concentration of iron (III) and aluminium oxides and hydroxides . They also contain quartz and kaolin , plus small amounts of other clay minerals and organic matter . The word "oxisol" comes from "oxide" in reference to

3149-401: The delineation of ecoregions an imperfect science. Another complication is that environmental conditions across an ecoregion boundary may change very gradually, e.g. the prairie-forest transition in the midwestern United States, making it difficult to identify an exact dividing boundary. Such transition zones are called ecotones . Ecoregions can be categorized using an algorithmic approach or

3216-707: The dominance of oxide minerals such as bauxite . In the World Reference Base for Soil Resources , oxisols are known as ferralsols . Present-day oxisols are found almost exclusively in tropical areas, in South America and Africa , almost always on highly stable continental cratons . In Southeast Asia , oxisols are found on remnants of the Cimmerian microcontinent , and on the Shan–Thai Terrane . In Thailand , rhodic ferralsols, called Yasothon soils, are said to have formed under humid tropical conditions in

3283-550: The early Tertiary , on an extensive plain later uplifted to form the Khorat Plateau . Characterized by a bright red color, these relict soils occur on uplands in a great semicircle around the southern rim, overlying associated gravel horizons said to have been cleared of sand by termites , in a prolonged and still on-going process of bioturbation . Xanthic ferralsols of the Khorat and Udon series, characterized by

3350-405: The early 1970s, the term 'ecoregion' was introduced (short for ecological region), and R.G. Bailey published the first comprehensive map of U.S. ecoregions in 1976. The term was used widely in scholarly literature in the 1980s and 1990s, and in 2001 scientists at the U.S. conservation organization World Wildlife Fund (WWF) codified and published the first global-scale map of Terrestrial Ecoregions of

3417-429: The establishment of a highly mechanized, capital intensive system of agriculture. There is also a strong agribusiness lobby in Brazil and in particular, the production of soybeans in the Cerrado is influenced by large corporations such as ADM, Cargill and Bunge, these latter two directly associated with the mass deforestation of this biome. One issue with expanding this reserve is that research needs to be done to choose

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3484-447: The first indigenous peoples occupying different regions in the Cerrado. Many groups among the indigenous were nomads and explored the Cerrado by hunting and collecting. Others practiced coivara agriculture, an itinerant type of slash-and-burn agriculture . The mixing of indigenous, quilombola maroon communities, extractivists, geraizeiros (living in the drier regions), riverbank dwellers and vazanteiros (living on floodplains) shaped

3551-407: The heavy vegetation of tropical rain forests would provide rich nutrients, but as rainfall passes through the litter on the forest floor the rain is acidified and leaches minerals from the above soil layers. This forces plants to get their nutrition from decaying litter as oxisols are quite infertile due to the lack of organic matter and the almost complete absence of soluble minerals leached by

3618-501: The land surface of the Earth into eight biogeographical realms containing 867 smaller terrestrial ecoregions (see list ). The WWF effort is a synthesis of many previous efforts to define and classify ecoregions. The eight realms follow the major floral and faunal boundaries, identified by botanists and zoologists, that separate the world's major plant and animal communities. Realm boundaries generally follow continental boundaries, or major barriers to plant and animal distribution, like

3685-529: The landscape and having a more highly structured habitat. Eleven mammal species are endemic to the Cerrado. Notable species include large herbivores like the Brazilian tapir and Pampas deer and large predators like the maned wolf , cougar , jaguar , giant otter , ocelot and jaguarundi . Although the diversity is much lower than in the adjacent Amazon and Atlantic Forest, several species of monkeys are present, including black-striped capuchin , black howler monkey and black-tufted marmoset . The insects of

3752-400: The late 1990s, between 14 million and 16 million tons of lime were being poured on Brazilian fields each year. The quantity rose to 25 million tons in 2003 and 2004, equaling around five tons of lime per hectare. This manipulation of the soil allowed for industrial agriculture to grow exponentially in the area. Researchers also developed tropical varieties of soybeans , until then

3819-593: The location of these reserves because the Cerrado biome is floristically very heterogeneous and constitutes a biological mosaic. Teams from the University of Brasília , CPAC and the Royal Botanic Garden Edinburgh have been collaborating on this project for a number of years supported by Brazilian, European Community and British funds. The project has recently been expanded into a major Anglo-Brazilian initiative, Conservation and Management of

3886-472: The oceans for conservation purposes is the system of large marine ecosystems (LMEs), developed by the US National Oceanic and Atmospheric Administration (NOAA). A freshwater ecoregion is a large area encompassing one or more freshwater systems that contains a distinct assemblage of natural freshwater communities and species. The freshwater species, dynamics, and environmental conditions within

3953-419: The paper industry, with the cultivation of several species of eucalyptus and pines , but as a secondary activity. Coffee produced in the Cerrado is now a major export. Charcoal production for Brazil's steel industry comes in second to agriculture in the Cerrado. They actually are quite intertwined. When land is being cleared to make more land for agriculture, the tree's trunks and roots are often used in

4020-402: The production of charcoal, helping to make money for the clearing. The Brazilian steel industry has traditionally always used the trunks and roots from the Cerrado for charcoal but now that the steel mills in the state of Minas Gerais are among the world's largest, it has taken a much higher toll on the Cerrado. However, recently because of the conservation efforts and the diminishing vegetation in

4087-415: The quality, health, and integrity of ecosystems ". "Characteristics of geographical phenomena" may include geology , physiography , vegetation, climate, hydrology , terrestrial and aquatic fauna , and soils, and may or may not include the impacts of human activity (e.g. land use patterns, vegetation changes). There is significant, but not absolute, spatial correlation among these characteristics, making

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4154-408: The term is somewhat vague. It has been used in many contexts: forest classifications (Loucks, 1962), biome classifications (Bailey, 1976, 2014), biogeographic classifications ( WWF / Global 200 scheme of Olson & Dinerstein, 1998), etc. The phrase "ecological region" was widely used throughout the 20th century by biologists and zoologists to define specific geographic areas in research. In

4221-454: The terrestrial ecoregions; only the priority conservation areas are listed. See Global 200 Marine ecoregions for a full list of marine ecoregions. In 2007, TNC and WWF refined and expanded this scheme to provide a system of comprehensive near shore (to 200 meters depth) Marine Ecoregions of the World (MEOW). The 232 individual marine ecoregions are grouped into 62 marine provinces , which in turn group into 12 marine realms , which represent

4288-913: The trees are predominantly conifers ( gymnosperms ), or whether they are predominantly broadleaf ( Angiosperms ) and mixed (broadleaf and conifer). Biome types like Mediterranean forests, woodlands, and scrub ; tundra ; and mangroves host very distinct ecological communities, and are recognized as distinct biome types as well. Marine ecoregions are: "Areas of relatively homogeneous species composition , clearly distinct from adjacent systems….In ecological terms, these are strongly cohesive units, sufficiently large to encompass ecological or life history processes for most sedentary species." They have been defined by The Nature Conservancy (TNC) and World Wildlife Fund (WWF) to aid in conservation activities for marine ecosystems . Forty-three priority marine ecoregions were delineated as part of WWF's Global 200 efforts. The scheme used to designate and classify marine ecoregions

4355-482: The unregulated expansion of industrial agriculture, the burning of vegetation for charcoal and the development of dams to provide irrigation are drawing criticisms and have been identified as potential threats to several Brazilian rivers. This industrial farming of the Cerrado, with the clearing of land for eucalyptus and soy plantations, has grown so much because of various forms of subsidy, including very generous tax incentives and low interest loans. This has resulted in

4422-427: The wet and humid climate . Oxisols are often used for tropical crops such as cocoa and rubber . In some cases, rice is grown on them. Permanent cropping of oxisols in low-income areas is very difficult because of low cation exchange capacities and high phosphorus fixation on iron and aluminium oxides (ligand exchange mechanism; inner sphere complex with phosphate). However, many oxisols can be cultivated over

4489-491: The world's 8 major biogeographical realms. Subsequent regional papers by the co-authors covering Africa, Indo-Pacific, and Latin America differentiate between ecoregions and bioregions, referring to the latter as "geographic clusters of ecoregions that may span several habitat types, but have strong biogeographic affinities, particularly at taxonomic levels higher than the species level (genus, family)". The specific goal of

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