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Chapada dos Guimarães National Park in the State
of Mato Grosso 65 kilometres from the city of Cuiabá,
is commonly known as Chapada dos Guimarães. Situated
north of the Pantanal, it is a jagged continuous escarpment
of reddish sandstone with drops of up to 400 metres.
Considered as the geodesic centre of South America,
rivers rise there which go to form two of the largest
and most important river basins in the world - the Amazon
and the Plata. Situated at 800 metres above sea level
the Chapada possesses a pleasant climate and can reach
low temperatures in winter, mainly in July and August.
A region of rare beauty, it also has beautiful waterfalls
and rock formations, covered by small forests, clear
fields and open pasture with stunted vegetation.
The large plateau that occupies the Brazilian central
highlands extends itself through the states of Goiás,
Minas Gerais and portions of the states of Tocantins,
Mato Grosso and South Mato Grosso. These five states
contain around 77% of all "cerrado" in Brazil."Cerrados",
woodland savannas which have once occupied 25% of the
Brazilian territory, in the western portion of central
Brazil, and in part of the states of São Paulo,
Paraná, Maranhão and Piauí. The
"cerrado" appears in areas of deep soil, little
stratified, leached and poor in organic matter, a kind
of latosolic soil.
A dry season of three to seven months leaves marks in
the region, causing the disappearance of the herbaceous
vegetation, and the scrub trees to loose their leaves.
One of the "cerrado" trees, the "ipê"
(Tabebuia ochracea) has been declared the symbol tree
of Brazil. The "cerrado" rivers don't normally
dry up, thus maintaining bordering woods called "mata
ciliar". The subterranean water table is 15-20
metres deep, sometimes more.
Nowadays the "cerrado" is being used for soya
cultivation very successfully, after the improvement
of its chemical conditions. Being an open region, it
has a typical fauna of herbivorous mammals, ground birds
and many reptiles. The handling of the "cerrado"
includes the use of fire, and the vegetation is adapted
to its passage. In a well preserved "cerrado",
the trees reach a height of 8 to 10 meters. Around 2
million km2 of the Brazilian territory are occupied
by "cerrados". Because of the subterranean
system of its vegetation, the "cerrado" is
rapidly restored after the frequent burnings.
Cerrado is the regional name given to the Brazilian
savannas. Around 85% of the great plateau which occupies
Central Brazil was originally dominated by the "cerrado"
landscape, representing around 1.5 to 2 million km2,
or approximately 20% of the country's surface. The "cerrado"
region's typical climate is hot, semi-humid and notedly
seasonal, with rainy summers and wet winters. The annual
rainfall is around 800 to 1600 mm. The soils are generally
very old, chemically poor and deep.
The
"cerrado" landscape characterises itself by
extensive savanna formations intercepted by woods along
the rivers, at the bottom of valleys. However, other
types of vegetation might appear in the "cerrado"
region, such as the humid fields or the "buriti"
palm paths, where the water table is superficial; alpine
pastures might occur at higher altitudes and the mesophytic
forests are situated on more fertile soils.
Even the exclusive savanna formations are not homogenous;
there is a great variation in the balance between the
quantities of trees and herbaceous vegetation, forming
a structural gradient that goes from the completely
open "cerrado" - the clean field, predominant
vegetation of grasses, without the presence of wooden
elements (trees and shrubs) - to the close "cerrado",
physiognomically forestal - the "cerradão"
("big cerrado"), with a great quantity of
trees and a forestal aspect. The intermediate forms
are the dirty field, the "cerrado" field and
the "cerrado" sensu stricto, according to
a growing density of trees.
The "cerrado" trees are very peculiar, with
twisted trunks, covered by a thick bark, and leaves
which are usually broad and rigid. Many herbaceous plants
have subterranean organs to store water and nutrients.
Thick barks and subterranean structures can be interpreted
as some of the many adaptations of this vegetation to
the periodic burnings to which it is submitted, in order
protect the plants from destruction and making them
capable of sprouting again after the fire. It is believed
that, as in many savannas in the world, the "cerrado"
ecosystems have been coexisting with fire since remote
times; initially as natural fires caused by lightening
or volcanic activity, and later caused by man. Taking
advantage of the sprouting of the herbaceous stratum
that follows a burning in the "cerrado", the
primitive inhabitants of these regions have learned
to use the fire as a tool, to increase the fodder offer
to their domesticated animals (herbivorous), a fact
that happens until today.
The great habitat variability in the different types
of "cerrado" supports an enormous diversity
of plant and animals species. Recent studies, such as
the one presented by J. A. Ratter and other authors
in "Avanços no Estudo da Biodiversidade
da Flora Lenhosa do Bioma Cerrado" (Advances in
the Study of the Biodiversity of the Ligneous Flora
of the "Cerrado" Bioma) in 1995, estimate
the number of vascular plants at around 5 thousand;
more than 1600 species of mammals, birds and reptiles
have already been identified in the "cerrado's"
ecosystems ("Cerrado's Fauna", Costa et al.,
1981). Among the diversity of invertebrates, the most
notable are the termites and the leaf-cutter ants ("saúvas").
They are the main herbivores of the "cerrado",
having a great importance in the consuming and decomposition
of organic matter, as well as constituting an important
food source to many other animal species.
On
the other hand, the urban pressure and the rapid establishment
of agricultural activities in the region have been rapidly
reducing the bio-diversity of the ecosystems. Until
the mid 60's, agricultural activities in the "cerrados"
were very limited, directed mainly at the extensive
production of beef cattle for subsistence or the local
market, since "cerrado" soils are naturally
infertile for agricultural production. After this period,
however, the urban and industrial development of the
Southeast Region has forced agriculture to the Central-West
Region.
The transfer of the country's capital to Brasilia has
been another focus of attraction of population to the
central region. From 1975 until the beginning of the
80's, many governmental programs have been launched
with the intent of stimulating the development of the
"cerrado" region, through subsidies for agriculture.
As a result, there has been a significant increase in
agricultural and cattle production.
Nowadays the "cerrado" region contributes
with more than 70% of the beef cattle production in
the country ("Pecuária de Corte no Brasil
Central"; Beef Cattle Production in Central Brazil,
Corrêa, 1989), and thanks to irrigation and soil
correcting techniques it is also an important production
centre of grains, mainly soya, beans, maize and rice.
Great extensions of "cerrado" are also utilised
in the production of cellulose pulp for the paper industry,
with the cultivation of several species of Eucalyptos
and Pinus, but still as a secondary activity.
The conservation of the "cerrados" natural
resources is represented by different categories of
conservation units, according to specific objectives:
eight national parks, various state parks and ecological
stations, comprising around 6.5% of the total "cerrado"
area ("Cerrado: Caracterização, Ocupação
e Perspectiva"; Cerrado: Characterisation, Occupation
and Perspectives; Dias, 1990). However, this extension
is still insufficient and more conservation units need
to be created for the protection of the bio-diversity
that is still preserved.
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