Grasslands of the World.pdf - Disasters and Conflicts - UNEP

V. ALEJANDRO DEREGIBUS AND MARTIN F. GARBULSKY
Other grasslands 429
Plate 11.9
A savannah type in SE Chaco, winter view.
stock were often penned at night. The boundaries of grazing territories were
ill-defined and herds’ grazing land often overlapped; this led to severe overgrazing
and rapid degradation of the pastoral cover. In less than fifty years, the
once-rich landscape had been almost sterilized and altered as a result of this “no
management ” system.
In Argentina , the main vegetation types are:
Humid to subhumid or Oriental Chaco is a parkland formation (Plate 11.8),
where patches of Quebracho Colorado Chaqueño (Schinopsis spp. ) forest alternate
with open grassland . There are also areas of Copernica alba palm, usually
under swamp conditions with accumulation of salts.
Arid and semi -arid Chaco. This is present in Argentina (Plate 11.9), in the
east of Bolivia and western Paraguay , with a small area in southwest Brazil . It
is a huge area of flat land, increasingly arid from east to west. Open grasslands
derived from forest through bush clearing and fire occupy a lesser area than
in the humid and subhumid zones . Forests are dominated by xerophytes and
are more open than in the eastern Chaco. Cacti are common among trees and
shrubs. Pastoral resources include a vast number of trees and shrubs, as well as
forage plants that are only found in man-made clearings.
The Montane zone is mostly in Argentina , but extends into Bolivia and
Paraguay . The landscape is broken by hills, which have a higher rainfall than
the lowlands; hillsides collect moist air coming from the Atlantic. The forest
vegetation contains many species found in the lower Chaco, and some trees of
higher rainfall areas; the grass cover is very limited.