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The Great Plains 



Overview 



The Great Plains of North 

 America are grasslands or 

 former grasslands that occupy more than 200 

 million ha (500 million acres) of land from cen- 

 tral Alberta, Canada, to the Texas Panhandle 

 and eastern New Mexico and from the front 

 range of the Rocky Mountains to the forest edge 

 in Minnesota, Missouri, and Oklahoma. The 

 natural plant communities dominating this land- 

 scape are known as grasslands or prairie 

 (French for meadow) and they are composed of 

 a rich complex of gras.ses and forbs. The cli- 

 mate, soils, and topography of the eastern Great 

 Plains are suitable for agriculture, and conse- 

 quently most of the original prairie has been 

 converted to row crops or pasture. In the west- 

 em Great Plains, large areas of intact grassland 

 are used as rangeland. Researchers estimate that 

 less than 1% of the original grasslands remains 

 undisturbed by human activities (Klopatek et al. 

 1979). 



Articles in this section focus on the effects of 

 more than 100 years of postsettlement manipu- 

 lation of the Great Plains ecosystem. For exam- 

 ple, fire was undoubtedly an important ecologi- 

 cal force in maintaining historical grassland 

 landscapes and species distributions. Following 

 fire suppression, woody plants have invaded 

 grasslands from adjacent forest and wooded 



stream valleys. In addition, water management 

 practices and the planting of farm and ranch 

 shelterbelts have resulted in the encroachment 

 of trees into grassland habitat. In many parts of 

 the Great Plains today, far more woody plants 

 exist than before agricultural development. As 

 endemic grassland birds have declined, they 

 have been replaced by eastern forest species 

 moving into newly wooded habitats (Knopf: Igl 

 and Johnson, both this section). 



Native prairie fishes also have experienced 

 significant losses in their historical distribu- 

 tions. Impoundments constructed on many 

 rivers and streams of the Great Plains have frag- 

 mented populations and eliminated colonization 

 of vacant habitat. Several prairie fishes, includ- 

 ing the Arkansas River shiner {Notropis girardi) 

 and the Arkansas River speckled chub 

 {Macrhyhopsis aestivalis tetraiieimis). have 

 shown significant declines in their distributions 

 and abundances (Echelle et al., this section). 



The fragmentation of native grassland due to 

 agricultural encroachment as well as the elimi- 

 nation of keystone species, such as bison [Bison 

 bison) and the white-tailed prairie dog 

 (Cynoinys leiiciinis). have led to a general 

 decline in prairie wildlife, although some 

 species have adapted to human-induced 

 changes and some have even increased in 



Science Editor 



Gary D. Willson 



National Biological Service 



Northern Prairie Science 



Center 



Central Plains/Ozark Field 



Station 



University of Missouri 



316 Gentry Hall 

 Columbia, MO 65211 



