Editing Prairie (section)

==Ecology==
[[File:Prairie grass.JPG|thumb|Prairie grasses]]
[[File:Wheatfield intersection in Southern Saskatchewan, Canada.jpg|thumb|Wheatfield intersection in the Southern [[Saskatchewan]] prairies, Canada]]
Prairie ecosystems in the United States and Canada are divided into the easternmost [[tallgrass prairie]], the westernmost [[shortgrass prairie]], and the central mixed-grass prairie. 
Tallgrass prairies receive over 30 inches of rainfall per year, whereas shortgrass prairies are much more arid, receiving only 12 inches or so, and mixed-grass prairies receive intermediate rainfall.<ref>{{cite web |title=Prairies and Grasslands - Wind Cave National Park |url=https://www.nps.gov/wica/learn/nature/prairies.htm |publisher=National Park Service}}</ref><ref>{{cite web|url=http://www.prairiefrontier.com/pages/families/prairies.html|title=Prairie Types Guide by Prairie Frontier|website=www.prairiefrontier.com}}</ref> Wet, mesic, and dry prairie ecosystems can also form more locally due to soil and terrain characteristics. Wet prairies may form in low-lying areas with poor drainage; dry prairie can be found on uplands or slopes. Dry prairie is the dominant habitat type in the Southern Canadian agricultural and climatic region which is known as [[Palliser's Triangle]]. It was once thought to be completely unarable, but is now one of the most important agricultural regions in Canada thanks to advances in irrigation technology.<ref name="thecanadianencyclopedia.ca"/>  

===Biodiversity===
The dominant plant life in prairies consists of [[grass]]es, which may include 40 to 60 different grass species. In addition to grasses, prairies can include over 300 species of flowering plants.<ref>{{cite web |title=Five facts about America's once vast prairie |url=https://www.reconnectwithnature.org/news-events/the-buzz/five-facts-about-americas-prairies/ |website=Forest Preserve District Will County}}</ref> The [[Konza Prairie Biological Station|Konza Tallgrass Prairie]] in Kansas hosts 250 species of native plants and provides habitat for 208 birds, 27 mammals, 25 reptiles, and over 3,000 insects.<ref>{{cite journal |last1=Rowe |first1=Helen I. |last2=Fargione |first2=Joseph |last3=Holland |first3=Jeffrey D. |title=Prairie Restorations can Protect Remnant Tallgrass Prairie Plant Communities |journal=The American Midland Naturalist |date=2013 |volume=170 |issue=1 |page=26|doi=10.1674/0003-0031-170.1.26 |s2cid=84748182 }}</ref>

Some of the dominant grasses of prairies are [[Sorghastrum nutans|Indian grass]], [[Andropogon gerardi|big bluestem]], [[Bouteloua curtipendula|side-oats grama]], [[Elymus canadensis|Canada wildrye]], and [[Panicum virgatum|switchgrass]].<ref>{{cite web |title=Dominant Prairie Plant Species |url=https://www.nrem.iastate.edu/research/STRIPS/dominant-prairie-plant-species |website=Iowa State University}}</ref>

Prairies are considered to be [[Fire ecology|fire-dependent ecosystems]]. Regular [[controlled burn]]ing by Native Americans, practices developed through observation of non-anthropogenic fire and its effects, maintained the biodiversity of the prairie, clearing away dead vegetation and preventing trees from shading out the diverse grasses and herbaceous plants. Prairies also depend on the presence of large grazing animals, particularly [[bison]].<ref>{{cite web |title=Fire and Grazing in the Prairie - Tallgrass Prairie National Preserve |url=https://www.nps.gov/tapr/learn/nature/fire-and-grazing-in-the-prairie.htm |website=National Park Service}}</ref>

Bison are important to the prairie ecosystem because they shape and alter the environment by grazing, trampling areas with their hooves, wallowing, and depositing manure.<ref>{{cite web |title=Bison Restoration |url=https://americanprairie.org/bison-restoration/ |publisher=American Prairie}}</ref> Bison eat more grass than flowering plants, increasing the diversity of plants in the prairie.<ref>{{cite web |title=Bison Eating Habits Influence the Prairie Ecosystem |url=https://www.nps.gov/articles/bison-bellows-3-24-16.htm |publisher=National Park Service}}</ref> Cattle are thought to prefer to eat flowering plants over grasses, but it is not known if that is because of inherent differences in the species or because farmed cattle tend to be confined in smaller areas.<ref>{{cite web |last1=Nosowitz |first1=Dan |title=Are Bison More Environmentally Friendly than Cattle? |url=https://modernfarmer.com/2016/09/bison-vs-cattle-environment/ |website=Modern Farmer|date=16 September 2016 }}</ref> Bison dung is a vital source of nutrients for prairie soil, spreads seeds, and supports over 1,000 insect species, including specialist [[dung beetle]]s which cannot subsist on the feces of any other animal.<ref>{{cite web |title=A Healthy Prairie Depends on Bison Poop |url=https://www.nps.gov/articles/bison-bellows-10-6-16.htm |publisher=National Park Service}}</ref>

===Degradation===
In spite of long recurrent [[drought]]s and occasional [[rain|torrential rains]], the grasslands of the [[Great Plains]] were not subject to great soil [[erosion]]. The root systems of native prairie grasses firmly held the soil in place to prevent run-off of soil. When the plant died, the [[Fungus|fungi]] and [[bacteria]] returned its nutrients to the soil. These deep roots also helped native prairie plants reach water in even the driest conditions. Native grasses suffer much less damage from dry conditions than many farm crops currently grown.<ref>{{cite web |url=https://ag.tennessee.edu/news/Pages/NR-2012-08-Drought-Grasses.aspx |title=Drought and Native Grasses
 |last=Keyser |first=Pat |date=2012-08-02 |publisher=The University of Tennessee Institute of Agriculture |access-date=2018-08-02 }}</ref><ref>{{cite web |url=https://www.southeastfarmpress.com/livestock/native-warm-season-grasses-weather-drought-provide-many-other-benefits |title=Native warm-season grasses weather drought, provide many other benefit |last=Taylor |first=Ciji |date=2013-06-03 |website=southeastfarmpress.com |publisher=Southeast FarmPress |access-date=2018-08-02 }}</ref> When the eastern [[Tallgrass prairie|tallgrass prairies]] were plowed and turned into agricultural lands, the prairie grasses with their strong root systems were destroyed. In combination with severe droughts that resulted in the [[Dust Bowl]], a major ecological disaster in which winds picked up the dry, unprotected prairie soil and formed it into "black blizzards" of airborne dirt that blackened the skies for days at a time across 19 states and forced 400,000 people to abandon the [[Great Plains]] ecoregion. The Dust Bowl was a major reason for the [[Great Depression]].<ref>{{cite web |title=The Dust Bowl |url=https://www.loc.gov/classroom-materials/united-states-history-primary-source-timeline/great-depression-and-world-war-ii-1929-1945/dust-bowl/ |website=Library of Congress}}</ref><ref>{{cite web |last1=Unger |first1=David J. |title=Saving America's Broken Prairie |url=https://undark.org/2017/04/26/saving-americas-broken-prairie/ |website=Undark|date=26 April 2017 }}</ref>