Geoscience Reference
In-Depth Information
Figure 15-9.
Pantanal region, South America (see Color Plate 15-9). The image clearly shows one of the largest
alluvial fans at the center, while the Pantanal Lakes are visible to the north and west of the alluvial fan as black
dots. The Brazilian landscape to the east and north of the fan indicates agricultural activities. Healthy vegetative
cover is observed in Bolivia to the west of the Pantanal. Red dots indicate active i res. Moderate Resolution Imaging
Spectroradiometer (MODIS) natural-color image from 16 June 2003; adapted from NASA's Earth Observatory
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season. The annual i sh
piracema
(reproductive)
migrations are a vivid illustration of the syn-
chronization of i sh life cycles to the l ood pulse
system. Fish i rst migrate upstream at the start
of the rainy season to spawn and then later
follow the l ood into seasonally inundated
grasslands for forage and habitat. During the
dry season as the l ood retreats they return to
perennial rivers, streams and lakes.
Even though the Pantanal is often identii ed
as a single ecosystem, it comprises a diverse
mosaic of habitat types based on soil character-
istics and the dynamics of inundation (Harris et
al. 2005). These conditions give rise to vegeta-
tion assemblages that have adapted to periodic
l ooding or near-drought conditions based on
seasonal climate variability. The Pantanal's
habitats include savanna grasslands (
campos
),
woodlands, gallery or riparian forests lining
river banks, elevated forested islands (
capões
),
marshes (
baias
and
corixos
) and scrubland
(Pearson and Beletsky 2005; Mittermeier et al.
2005).
This montage of habitats contributes to a
high level of species richness and density includ-
ing some 1863 species of vascular plants, 263
species of i sh, 463 species of birds and 132
mammal species (Alho 2005, p. 224). Among the
more renowned species, the Pantanal jaguar
(
Panthera onca palustris
), the world's largest
rodent, the capybara (
Hydrochaeris hydro-
chaeris
), the giant river otter (
Pteronura brasil-
iensis
), the marsh deer (
Blastocerus dichotomus
),
and the abundant Pantanal caiman (
Caiman
yacare
) comprise just a few. The wetlands also
serve as stopover points for regional bird l yways
and provide seasonal foraging and nesting
habitat for numerous migratory waterfowl and
shorebirds. Moreover, 19 recorded species of
parrots, 13 species of heron and egrets, spoon-
bills, ibis, kingi sher birds, jabiru (
Jabiru mycte-
ria
), the world's largest stork, and rheas (
Rhea
