短草草 原是位於北美大平原的生態系。短草草原中兩種最主要的草類是藍格拉馬( Bouteloua gracilis ) 和水牛草 ( Bouteloua dactyloides )，草原中兩種次要的草類是油草( Tridens flavus ) 和側油草( Bouteloua curtipendula )。該草原以前是靠主要物種美洲野牛的放牧壓力維持的。由於半乾旱氣候，短草草原的平均降水量比東部高大的混合草草原少。[ 1 ]
草原包括西至洛磯山脈東麓的土地，東至內布拉斯加州，北至薩斯喀徹溫省。這片草原橫跨艾伯塔省、懷俄明州、蒙大拿州、北達科他州、南達科他州和堪薩斯州的部分地區，向南穿過科羅拉多州、俄克拉荷馬州、德克薩斯州和新墨西哥州的高原。[ 2 ]
歷史
[編輯]短草草原有著悠久的人類歷史。基奧瓦人、科曼奇人和阿拉帕霍人佔領了這片土地並獵殺野牛和叉角羚。每個季節，這些部落都會在落基山脈等鄰近的山脈進行狩獵。為了管理草原，這些部落和他們的祖先很可能會使用火。它們會造成燃料中斷、植被或其他可燃材料中的間隙，作為減緩或阻止叢林火災或野火進展的屏障。防火帶可能會在沒有植被或其他燃料的地區自然發生，例如定居點周圍的河流、湖泊或峽谷。這些燃料中斷也會吸引大型草食動物來到新生長的地方。[ 3 ]
歐洲探險家、捕獵者和毛皮貿易商開始在短草草原上定居。他們發展了採礦經濟，導致了草原後來的成長和工業化。 19世紀中後期，鐵路拓寬了運輸渠道，並有助於增加定居點，主要是在農村和小城鎮。隨著越來越多的人開始在草原上定居，大規模的牛羊牧場也隨之增多，後來帶動了金、銀、銅礦社區的發展。[ 4 ]
集塵碗
[編輯]在1920年代，厄爾尼諾現象為整個草原帶來更多降水並促進植物生長，對短草草原作物生長的成功發揮了重要作用。這項成功鼓勵農民購買更有效率的農業設備。有了新設備，農民翻出了故土，露出了土壤。到了 20 世紀 30 年代，已經來不及用草來保護土壤了。未受保護的土壤被風吹散並形成沙塵暴，導致了沙塵暴。
使徒行傳
[編輯]1985 年食品安全法
[編輯]1985 年《糧食安全法》允許降低商品價格並提供收入支持。該法案也為乳牛群收購計畫奠定了基礎。該法案對美國農業部的其他幾個項目進行了修改。
保護儲備計劃
[編輯]參與該計畫的農民同意廢除因農業生產和放牧而造成環境破壞的土地，以改善和重新種植健康的草地和棲息地，以換取每年的租金。[ 5 ]
今天
[編輯]短草草原大多是家畜放牧的，人口依賴農業。然而，能源和採礦勘探有所增加。許多物種急劇減少，但該地區的農民和牧場主證明，良好的土地管理實踐有助於維持本地物種、自然群落和生態系統。[ 6 ]
From Wikipedia, the free encyclopedia
The shortgrass prairie is an ecosystem located in the Great Plains of North America. The two most dominant grasses in the shortgrass prairie are blue grama (Bouteloua gracilis) and buffalograss (Bouteloua dactyloides), the two less dominant grasses in the prairie are greasegrass (Tridens flavus) and sideoats grama (Bouteloua curtipendula). The prairie was formerly maintained by grazing pressure of American bison, which is the keystone species. Due to its semiarid climate, the shortgrass prairie receives on average less precipitation than that of the tall and mixed grass prairies to the east.[1]
The prairie includes lands to the west as far as the eastern foothills of the Rocky Mountains and extends east as far as Nebraska and north into Saskatchewan. The prairie stretches through parts of Alberta, Wyoming, Montana, North Dakota, South Dakota, and Kansas, and passes south through the high plains of Colorado, Oklahoma, Texas, and New Mexico.[2]
History
[edit]The shortgrass prairie has a long human history. The Kiowa, Comanche, and Arapaho peoples occupied the land and hunted bison and pronghorn. Seasonally, these tribes would stage hunts in the adjacent mountains such as the Rocky Mountains. To manage the prairie, those tribes and their predecessors likely used fire. They would create fuel breaks, a gap in vegetation or other combustible material that acts as a barrier to slow or stop the progress of a brushfire or wildfire. A firebreak may occur naturally in areas without vegetation or other fuel, such as a river, lake or canyon around their settlements. These fuel breaks would also entice large herbivores to patches of fresh new growth.[3]
European explorers, trappers, and fur traders began to settle the shortgrass prairie. They developed an extractive economy that led to the later growth and industrialization of the prairie. In the mid-to-late 19th century, the railroads expanded transportation channels and helped to increase settlement, predominantly in rural and small towns. While more people began to settle in the prairie, large-scale cattle and sheep ranching increased as well and later led to the development of gold, silver, and copper mining communities.[4]
Dust Bowl
[edit]In the 1920s, El Niño played a big role in the success of crop growing in the shortgrass prairie by causing more precipitation throughout the prairie and promoting plant growth. The success encouraged farmers to buy more efficient farming equipment. With the new equipment, farmers turned up the native land, exposing the soil. By the time the 1930s came around, it was too late to protect the soil with grass. The unprotected soil contributed to the Dust Bowl by being blown around and creating dust storms.
Acts
[edit]Food Security Act of 1985
[edit]The Food Security Act of 1985 allowed for lower commodity prices and income supports. This Act also laid the foundation for the dairy herd buyout program. The Act made changes to several other USDA programs.
Conservation Reserve Program
[edit]Farmers enrolled in the program agree to abolish environmentally destroyed land from agricultural production and cattle grazing to improve and regrow healthy grass and habitats in exchange for a yearly rental payment.[5]
Today
[edit]Much of the shortgrass prairie is grazed by domestic livestock, with a human population that is dependent upon agriculture. However, energy and mining exploration have increased. There has been a precipitous decline of many species, but farmers and ranchers of the region are demonstrating that sound land management practices can help sustain the native species, natural communities, and ecosystems.[6]
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