The Great Plains is a mixture of cropland and grassland mainly used for agricultural purposes, with grasslands under continual threat of conversion to cropland. Agriculturists are advocating for the integration of crop-livestock systems (ICLS) to recouple nutrient cycles, improve biodiversity, and increase resilience of agricultural operations. We address the benefits of ICLS in the Great Plains, contending that focus on improving soil health and financial stability of agricultural operations should reduce the conversion of grasslands to cropland. Using US Department of Agriculture National Agricultural Statistics Service Census of Agriculture survey data from the 1925−2017 category “cropland used only for pasture or grazing,” which represents land that had been cropped but converted to annual/perennial pasture and grazed, we showcase that the number of farms and the land area in this category is a reasonable proxy of ICLS. As expected, ICLS dramatically decreased in the entire United States from 1925 to 1945, but from 1945 to 2002 in the Great Plains ICLS remained relatively constant, providing evidence of sustained crop-livestock integration. Consistent high numbers of beef cows during this period and the wide availability of forages and crop residues for ruminants facilitated opportunities for producers to use ICLS on their individual operations (within farm) or among operations where row crop farmers and forage-based producers integrated beef cattle use across the landscape (among farms). This integration, however, was decoupled from 2006 to 2013, a period of high grain prices. As a result, economic value of grasslands was decreased and conversion to cropland was increased. Thus, conservation efforts in the Great Plains for grasslands should focus on keeping grasslands intact for provision of multiple ecosystem goods and services by emphasizing incorporation of ICLS within and among farms to reduce the risk of converting grassland to cropland.

大平原是农田和草原的混合物，主要用于农业目的，而草原一直面临着转换为农田的威胁。农业学家们倡导整合农作物－牲畜系统（ICLS），以重新耦合养分循环，改善生物多样性并提高农业生产的适应力。我们讨论了大草原地区ICLS的好处，认为将重点放在改善土壤健康和农业运营的财务稳定性上，应减少草地向农田的转化。使用美国农业部国家农业统计局农业普查的1925-2017年“仅用于牧场或放牧的耕地”类别的调查数据，该耕地表示已耕种但转换为年度/多年生牧场并放牧的土地，我们证明该类别中的农场数量和土地面积是ICLS的合理替代。不出所料，从1925年到1945年，整个美国的ICLS急剧下降，但是从1945年到2002年，美国大平原地区的ICLS保持相对稳定，提供了持续的农作物-畜牧业融合的证据。在此期间，稳定的大量奶牛以及广泛的反刍动物饲草和农作物残渣为生产者提供了机会，使生产者有机会在其个体经营（农场内）或行间种植农户和牧草生产者整合肉牛的经营中使用ICLS在整个景观中使用（在农场中）。然而，这种整合是从2006年到2013年（粮食价格高涨的时期）解耦的。结果是，草地的经济价值下降，耕地转化增加。因此，大平原地区的草地保护工作应着重于通过强调在农场内部和农场之间纳入ICLS来减少草地转化为农田的风险，从而保持草地完好无损，以提供多种生态系统产品和服务。