The Chiquitano dry forests is a
tropical dry broadleaf forest ecoregion
An ecoregion (ecological region) or ecozone (ecological zone) is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than a biogeographic realm. Ecoregions cover relatively large areas of l ...
in
Bolivia
, image_flag = Bandera de Bolivia (Estado).svg
, flag_alt = Horizontal tricolor (red, yellow, and green from top to bottom) with the coat of arms of Bolivia in the center
, flag_alt2 = 7 × 7 square p ...
and
Brazil
Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...
. The ecoregion is named for the
Chiquitano
The Chiquitano or Chiquitos are an indigenous people of Bolivia, with a small number also living in Brazil. The Chiquitano primarily live in the Chiquitania tropical savanna of Santa Cruz Department, Bolivia, with a small number also living in Be ...
people who live in the region.
[
]
Setting
The Chiquitano dry forests cover an area of . The ecoregion lies east of the Andes
The Andes, Andes Mountains or Andean Mountains (; ) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is long, wide (widest between 18°S – 20°S ...
in the lowlands of eastern Bolivia and the Brazilian states of Mato Grosso
Mato Grosso ( – lit. "Thick Bush") is one of the states of Brazil, the third largest by area, located in the Central-West region. The state has 1.66% of the Brazilian population and is responsible for 1.9% of the Brazilian GDP.
Neighboring ...
and Rondônia
Rondônia () is one of the 26 states of Brazil, located in the northern subdivision of the country (central-western part). To the west is a short border with the state of Acre, to the north is the state of Amazonas, in the east is Mato Grosso, ...
.
The World Wildlife Fund
The World Wide Fund for Nature Inc. (WWF) is an international non-governmental organization founded in 1961 that works in the field of wilderness preservation and the reduction of human impact on the environment. It was formerly named the Wo ...
includes the Chiquitano dry forests in the Amazon biome
The Amazon biome ( pt, Bioma Amazônia) contains the Amazon rainforest, an area of tropical rainforest, and other ecoregions that cover most of the Amazon basin and some adjacent areas to the north and east. The biome contains blackwater and white ...
.
The ecoregion adjoins the Dry Chaco ecoregion to the south and the Pantanal
The Pantanal () is a natural region encompassing the world's largest tropical wetland area, and the world's largest flooded grasslands. It is located mostly within the Brazilian state of Mato Grosso do Sul, but it extends into Mato Grosso and p ...
ecoregion to the southeast.
To the northeast it blends into the Cerrado
The ''Cerrado'' (, ) is a vast ecoregion of tropical savanna in eastern Brazil, particularly in the states of Goiás, Mato Grosso do Sul, Mato Grosso, Tocantins, Minas Gerais, and the Federal District. The core areas of the Cerrado biome are t ...
ecoregion.
To the northwest it adjoins the Madeira-Tapajós moist forests and Southwest Amazon moist forests
The Southwest Amazon moist forests (NT0166) is an ecoregion located in the Upper Amazon basin.
The forest is characterized by a relatively flat landscape with alluvial plains dissected by undulating hills or high terraces. The biota of the so ...
ecoregions.
Climate
The climate of the Chiquitano dry forests is tropical
The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in
the Southern Hemisphere at S. The tropics are also referred to ...
, with a strong dry season during the southern hemisphere winter. Average precipitation ranges between 1,000mm in the south and 2,000mm in the northwest, varying with orography.
Flora
There are several common plant communities, or associations, which vary in structure and characteristic species. The forests of the region are adapted to the strong seasonal variation in rainfall, including wet-season flooding and dry-season fires. Many trees are deciduous, losing their leaves during the winter dry season, Deciduousness is more common in the semi-arid south. [Killeen, Timothy & Chavez, Ezequial & Peña-Claros, M. & Toledo, Marisol & Arroyo, Luzmila & Caballero, Judith & Correa, Lisete & Guillén, René & Quevedo Sopepi, Roberto & Saldias, Mario & Soria, Liliana & Uslar, Ynés & Vargas, Israel & Steininger, Marc. (2006). The Chiquitano Dry Forest, the Transition between Humid and Dry Forest in Eastern Lowland Bolivia. ''Neotropical Savannas and Seasonally Dry Forests: Plant Diversity, Biogeography and Conservation''. 213-233. 10.1201/9781420004496.ch9.]
The soto/curupaú association includes the trees soto (''Schinopsis brasiliensis
''Schinopsis brasiliensis'' is a species of flowering plant in the cashew family known by the common names ''baraúna'' or ''braúna''.Cardoso, M. P., et al. (2005)A new alkyl phenol from ''Schinopsis brasiliensis''.''Natural Product Research'' ...
''), curupaú ('' Anadenanthera macrocarpa''), momoqui ('' Caesalpinia pluviosa''), morado (''Machaerium scleroxylon
''Machaerium'' is the scientific name of two genera of organisms and may refer to:
* ''Machaerium'' (fly), a genus of insects in the family Dolichopodidae
* ''Machaerium'' (plant), a genus of plants in the family Fabaceae
{{Genus disambiguat ...
''), roble (''Amburana cearensis
''Amburana cearensis'' (Portuguese common names; ambaúrana, amburana, amburana de cheiro, angelim, baru, cabocla, cerejeira rajada, cumaré, cumaru, cumaru de cheiro, cumaru do ceará, cumbaru das caatingas, emburana, emburana de cheiro, imbura ...
''), and cedro ('' Cedrela fissilis''). This association is found on well-drained soils. Trees form a canopy averaging 20 meters in height with emergent trees up to 30 meters. The canopy is 80% closed, and there is an understory of shrubs and herbs.[ Emergent soto trees are some of the largest in the forest, reaching up to 35 meters in height and living up to 500 years.
In the cuchi/curupaú association, either curupaú ('' Anadenanthera macrocarpa'') or cuchi ('']Astronium urundeuva
''Astronium'' is a genus of flowering plants in the cashew family, Anacardiaceae. It is native to Central and South America.
''Astronium'' is a genus of dioecious trees. Leaves are deciduous, alternate, and odd-pinnate.
Species
, Plants of the ...
'') predominates. It grows on well-drained but nutrient-poor soils, including rocky mountain slopes and sandy lowland soils. The canopy varies from 10 to 15 meters in height and is 65% closed, with emergent trees up to 25 meters high.[
The cuta/ajo-ajo association is predominantly cuta ('']Phyllostylon rhamnoides
''Phyllostylon'' is a genus of plant in family Ulmaceae
The Ulmaceae () are a family of flowering plants that includes the elms (genus ''Ulmus''), and the zelkovas (genus ''Zelkova''). Members of the family are widely distributed throughout t ...
'') and ajo-ajo (''Gallesia integrifolia
''Gallesia'' is a monotypic genus of flowering plants belonging to the family Petiveriaceae. It only contains one species; ''Gallesia integrifolia'' (Spreng.) Harms
Its native range is western South America to Brazil. It is found in the countrie ...
''). This association is found on seasonally-flooded soils near streams.
The tajibo/tusequi association is of Tajibo (''Tabebuia heptaphylla
''Handroanthus heptaphyllus'', commonly referred to as the pink trumpet tree or pink tab, is a Bignoniaceae tree native to tropical and subtropical regions of South America. It grows in the high forest watershed of the Paraná River, Paraguay Ri ...
'') and tusequi (''Machaerium hirtum
''Machaerium'' is the scientific name of two genera of organisms and may refer to:
* ''Machaerium'' (fly), a genus of insects in the family Dolichopodidae
* ''Machaerium'' (plant), a genus of plants in the family Fabaceae
{{Genus disambiguat ...
''). It forms patches of forest on low rises (half a meter to a meter) surrounded by open savanna.[
The ecoregion also has areas of grassy savanna similar to the ]Cerrado
The ''Cerrado'' (, ) is a vast ecoregion of tropical savanna in eastern Brazil, particularly in the states of Goiás, Mato Grosso do Sul, Mato Grosso, Tocantins, Minas Gerais, and the Federal District. The core areas of the Cerrado biome are t ...
savannas further east.
Fauna
The ecoregion has 42 species of mammals, including marsh deer
The marsh deer (''Blastocerus dichotomus'') is the largest deer species from South America reaching a length of and a shoulder height of . It is found in Argentina, Bolivia, Peru, Brazil, Uruguay and Paraguay. Formerly found in much of tropical ...
(''Blastocerus dichotomus''), white-lipped peccary
The white-lipped peccary (''Tayassu pecari'') is a species of peccary found in Central America, Central and South America and the only member of the genus ''Tayassu''. Multiple subspecies have been identified. White-lipped peccaries are similar ...
(''Tayassu pecari''), giant armadillo
The giant armadillo (''Priodontes maximus''), colloquially ''tatu-canastra'', ''tatou'', ''ocarro'' or ''tatú carreta'', is the largest living species of armadillo (although their extinct relatives, the Glyptodontidae, glyptodonts, were much l ...
(''Priodontes maximus''), jaguar
The jaguar (''Panthera onca'') is a large cat species and the only living member of the genus '' Panthera'' native to the Americas. With a body length of up to and a weight of up to , it is the largest cat species in the Americas and the th ...
(''Panthera onca''), maned wolf
The maned wolf (''Chrysocyon brachyurus'') is a large canine of South America. It is found in Argentina, Brazil, Bolivia, Peru, and Paraguay, and is almost extinct in Uruguay. Its markings resemble those of foxes, but it is neither a fox nor a w ...
(''Chrysocyon brachyurus''), giant otter
The giant otter or giant river otter (''Pteronura brasiliensis'') is a South American carnivorous mammal. It is the longest member of the weasel family, Mustelidae, a globally successful group of predators, reaching up to . Atypical of musteli ...
(''Pteronura brasiliensis''), and the rodent Goodfellow's tuco-tuco (''Ctenomys goodfellowi'').[
Native birds include the ]black-and-tawny seedeater
The black-and-tawny seedeater (''Sporophila nigrorufa'') is a species of bird in the family Thraupidae.
It is found in the Pantanal of eastern Bolivia and adjacent southwestern Brazil. Its natural habitat is subtropical or tropical seasonally w ...
(''Sporophila nigrorufa''). Native reptiles include the broad-snouted caiman (''Caiman latirostris'').[
]
Conservation and protected areas
During the period from 2004 to 2011 the ecoregion experienced an annual rate of habitat loss of 0.62%.
In response to indigenous demands for control over their home territories, the Bolivian government issued a decree in 1990 designating indigenous territories in the lowlands, and acknowledging the rights of indigenous peoples to collectively govern those territories. A 1993 agrarian reform law acknowledged indigenous communities' collective land ownership and formalized Native Community Lands Native Community Lands ( es, Tierra Comunitaria de Origen, acronym: TCO; also translated as Communal Lands of Origin), according to Bolivian law, are territories held by indigenous people through collective title. The creation of these territories h ...
(called ''Tierras Comunitarias de Origen'' , or TCOs) as the vehicle for ownership, and the 1995 constitutional reform further guaranteed the rights of indigenous peoples to Native Community Lands. Portions of the dry forests are within TCOs. A 1996 reform of Bolivia's forestry law required forest management plans and forest inventories, established harvest limits, and guaranteed the rights of indigenous communities to manage timber harvesting on forest lands within TCOs, and to engage in customary forms of forest product harvesting without central government approval.
From August to November 2019, fires burned 1.4 million hectares of the dry forests, an estimated 12% of the Chiquitano forest area before the fires. Earlier in 2019 the Bolivian government issued a decree supporting clearance of forest lands in the Chiquitano and Amazon regions for cattle and soya production. Civil society organizations concluded the fires were mostly deliberately set by people seeking to clear land, and linked the increase in fires to the change in government policy. Those organizations and indigenous leaders petitioned the government to repeal the pro-clearance policies, better protect the forests, and uphold indigenous land rights.[Wordley, Claire F.R. "It’s not just Brazil’s Amazon rainforest that’s ablaze – Bolivian fires are threatening people and wildlife." ''The Conversatation'', 23 August 2019. Accessed 15 July 2020]
/ref>
A 2017 assessment found that 55,861 km², or 24%, of the ecoregion is in protected areas.[ Protected areas include ]Noel Kempff Mercado National Park
Noel Kempff Mercado National Park is a national park in northeast Santa Cruz Department (Bolivia), Santa Cruz Department, Province of José Miguel de Velasco, Bolivia, on the border with Brazil.
Description
Noel Kempff Mercado National Park cover ...
and Ríos Blanco y Negro Wildlife Reserve
Rios Blanco y Negro Wildlife Reserve ( es, Reserva de Vida Silvestre Ríos Blanco y Negro, RVSRByN) is a departmental protected area in Ñuflo de Chávez Province, Ñuflo de Chávez and Guarayos Province, Guarayos provinces in the northern part of ...
in Bolivia.
External links
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References
Sources
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{{authority control
Ecoregions of Bolivia
Ecoregions of Brazil
Forests of Bolivia
Forests of Brazil
Amazon biome
Neotropical dry broadleaf forests