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Background: Soil organic C and N data from privately managed pastures in the southeastern United States are relatively scant. Methods: A paired‐farm approach was deployed to determine how a variety of soil health parameters related to nutrient and water cycling might be altered under grazed, botanically diverse perennial pastures compared with annual monoculture croplands in three Major Land Resource Areas of the southeastern United States. Results: Soil stability index averaged 0.64 and 0.91 mm mm−1 under cropland and grazed pasture, respectively, suggesting that pastures had a more stable soil surface that was resistant to erosion and allowed rapid water infiltration. Surface‐soil organic C and N fractions (i.e., total, particulate, and mineralizable fractions at 0–10 cm depth) were greater under pasture than under cropland. Across locations, root‐zone enrichments (0–30 cm depth) of organic C and N fractions were greater under pasture than under cropland. Within locations, root‐zone enrichment of total soil N was greater (p < 0.05) under pasture than under cropland in the Blue Ridge (2.87 vs. 1.10 Mg N ha−1, respectively) and the Piedmont (2.80 vs. 2.10 Mg N ha−1), but not in the Blackland Prairie (2.40 vs. 2.12 Mg N ha−1). Conclusions: This study provides evidence that rotationally grazed, perennial grasslands can store more soil organic C and N and improve soil surface stability conditions compared with neighboring croplands producing commodity feed grains for feedlot finishing. [ABSTRACT FROM AUTHOR]

Agriculture has undergone dramatic technological and cultural changes over the past century. Many would argue that the changes have been unquestionably positive with huge gains in productivity, reduced labour requirements, and alleviation of food insecurity for most people. However, the adoption of increasingly specialized and separated crop and livestock enterprises has also had widespread negative consequences resulting in (a) decline in biodiversity, (b) degradation of groundwater and surface waters with agrochemical pollutants, (c) poor soil health with monoculture crop production and frequent soil disturbance, (d) intensive greenhouse gas emissions from both specialized cropping systems relying on external inputs and concentrated animal feeding operations that accumulate wastes, and (e) general lack of ecological integrity among components of these specialized systems. Diversified agricultural systems using annual and perennial forages offer opportunities to elevate ecological synergies when crop and livestock operations are integrated. Integrated crop‐livestock systems can internalize nutrient cycling, provide cultural control of weeds, insects and diseases, and share resources in a circular‐based agroecosystem. Cover crops could be transitioned into nutritious annual forages for livestock grazing on currently specialized crop production farms with appropriate local incentives. Perennial forages in ley farming or in pasture‐crop rotations have historical relevance and are a proven practice for conserving nutrients, improving soil health and enhancing biodiversity. Redesigning contemporary agriculture with mixed‐use farming techniques could greatly reduce soil erosion, improve water quality, and invigorate soil health. We suggest that incorporating different types of forages across a diverse landscape can enhance agricultural sustainability and ecological integrity. [ABSTRACT FROM AUTHOR]