The Human Impacts on the Great Plains

The Human Impacts on the Great Plains
       
                       The human has had historically impacted the Great Plain pretty negatively. The most general force that changed the ecosystem of the Great Plain was through the development of agriculture and overgrazing following the human settlements (Hidinger 2000). The farmers, moreover, are changing their farms into monoculture rather than diversifying the farms and are more and more converting marginal lands into agricultural lands with the application of genetically modified crops (Higgins, Naugle and Forman 2002). This caused the severe loss of wildlife habitats and the decline of biodiversity (Higgins, Naugle and Forman 2002). In order to sustain this intensification of farming, nitrogen fertilizers were widely used which then turned to nitrate solute and was leached into the ground water (Wishart 2006). It is noted that Homestead Act of 1862 and Canada Dominion Act of 1872 allowed the sale of Federal land to private owners, which exacerbated the conversion to agriculture (Samson, Knopf and Ostlie 2004). The intensive use of aquifer to satisfy the increasing acreage of irrigated land also caused the drastic shrinkage of the aquifer by 200 million acres (Wishart 2006) Following the European settlement, the Bison were killed in large number for their furs and the competition for forage between bison and horses brought from Europe as well as the diseases transmitted to bison from horses decreased the number of the population of bison (Wishart 2006). The transportation of furs in fur trade also resulted in the deforestation of woodlands along Mississippi River to provide fuels for the steamboats (Wishart 2006). The development of coal, oil and gas would pollute the streams, drain the aquifers and cause environmental damages through their drilling operations (Wishart 2006). It should be noticed that the suppression of fire has caused the change of ecosystem from grasslands to forests. It introduced shrubs which would otherwise have been stopped by intermittent fire. It also reduced the productivity of the grasslands since some of the biomasses could not be decomposed without fire. (Courtwright 2007)
     

 

       There are, amid the bad news, positive impacts from the Great Plains management. The Nature Conservancy has been preserving native land and biodiversity through acquisitions, conservation easement and land exchange between government and private land owners (Wishart 2006). There have also been 110 National Wildlife refuges set up in the Great Plains which constitute 22% of the total national forest in the whole nation (Wishart 2006). Individual farmers have also been gradually trying to implement diversified crops and use less chemical pesticides to be more sustainable (Wishart 2006).