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

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Figure 6.1
The extent of grasslands in North America.
Grasslands of the world
Figure 6.2
Map showing grassland
types in central USA .
SOURCE: Lauenroth et al.,1994.
grassland prior to European settlement were pristine and little modified by
man (Deneven, 1996; Leopold et al., 1963). However, Flores (1999) presents
persuasive arguments that native American populations were relatively high in
the Great Plains and probably exerted considerable influence on other components
of these grassland ecosystems .
LOCATION AND GENERAL DESCRIPTION OF THE REGION
The extent of grasslands in North America is shown in general terms in Figure 6.1.
At coarse scales the Great Plains grassland is commonly divided into tall-grass
(true prairie), mixed - (or mid-)grass , and short-grass (Bazzaz and Parrish, 1982;
Gleason and Cronquist, 1964; Lauenroth, et al., 1994; Laycock, 1979; Sieg, Flather
and McCanny, 1999; Sims, 1988) (Figure 6.2). Plates 6.1a–c show examples of the