Amazon region
Since 1988, Brazil
National Institute of Space Research (INPE) has developed a
deforestation mapping program in the Amazon that became a world
reference for tropical forest monitoring (PRODES).
The first monitoring
system that gave manually and later digitally annual deforestation rate
estimations for the overall Brazilian Amazon based on LANDSAT images was
recently improved to provide near real time deforestation areas
detection (DETER). This system made possible a large deforestation
control program in Brazil that limited significantly the progression of
deforestation in the region. These monitoring programs are essential for
the conservation of the tropical biodiversity but it is now considered
that a specific monitoring of the areas already deforested should
complement such effort. This monitoring is essential to define and apply
specific conservation strategies for the regions that have a
human-impacted landscape. In recent studies, certain types of
human-modified areas such as secondary forest, agroforestry or even
pasture have shown a high biodiversity conservation capacity for plants,
trees and fauna. On the opposite, some landscapes are devastating the
biodiversity such as soybean fields, sugarcane or palm oil plantations.
To take in account this biodiversity gradient within the human-modified
areas and prepare future conservation strategies, it is then necessary
to provide up-to-date land cover maps of the so-called "deforested areas".
Description of the test sites
Two study sites were defined in the
western part of the Legal Amazon region. Each test site is defined by
the window of a LANDSAT image of 120 km x 120 km.
The first test site is
located around Santarem. Santarem is a town located in the
western part of the Para State at the confluence of the Amazon and
Tapajos rivers. While conservation of primary forest should represent
80% of the lands according to Brazilian laws, the deforestation has
continued and even increased with the recent installation of a port
facility for processing soybean in Santarem what enhanced soybean
production in the region. This test site is particularly interesting
since it concentrates a high diversity of land cover situations with
small patches of deforestation. It is considered as a complex region to
map the land cover of the human-modified areas because of the large
diversity of situations and the high landscape fragmentation.
The second test site is
located in the north part of the Tucurui Lake between Belem and
Maraba. It is a region where deforestation was very intense partly
because of the presence of steel-making centres that use primary forest
to produce charcoal. In this region, eucalyptus plantations have grown
to produce more sustainable charcoal and avoid deforestation. It is also
an area where pasture degradation is common. The mapping of the actual
land cover situation will be also useful to plan reforestation forest in
this particular region.
For both test sites the
products delivered by BIO_SOS will allow to discriminate pastures,
agricultural fields, remnant primary growth forest patches, riparian
strips, secondary forests and agroforestry.
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