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Highlights: [•] Integrated crop-livestock systems are effectively implemented in every region of the U.S. [•] New technologies facilitate successful adoption of crop-livestock systems. [•] Adoption of crop-livestock systems in the U.S. occurs primarily among livestock managers. [•] Cash crop managers have few current incentives to incorporate livestock into their crop systems. [ABSTRACT FROM AUTHOR]

Abstract: Botanical composition and forage productivity of mixed cool- and warm-season perennial pastures are important determinants of agricultural sustainability. Effects of three sources of nutrient (inorganic only, organic+inorganic combination, and organic only) and four utilization regimes (unharvested, low and high grazing pressure, and hayed) were evaluated on botanical composition, residual forage mass, and forage production during seven years of management on tall fescue (Lolium arundinaceum, a cool-season C3 grass) overseeded into existing bermudagrass (Cynodon dactylon, a warm-season C4 grass) sod in Georgia. Nutrient source had few major impacts on responses, except for greater hay yield with organic fertilization (broiler litter) than with organic+inorganic and inorganic only fertilization. Botanical composition of grazed pastures shifted with time from initial dominance with bermudagrass (∼50% basal area) to mixed composition of tall fescue (60%)/bermudagrass (36%) under low grazing pressure and tall fescue (45%)/bermudagrass (48%) under high grazing pressure. To maintain optimum botanical composition and productivity for year-round sustainable grazing, forage mass needs to be balanced within a maximum threshold to avoid deterioration of forage quality and a minimum threshold to avoid environmental degradation. [Copyright &y& Elsevier]

The article discusses the benefits and barriers of well-managed grazing-based farming system and promotes adoption of this conservation tool in the eastern U.S. It informs that this system provides society-wide environment services, productivity and profit to individual producers. It proposes the local, state and federal programs to support grazing system and encourages development of policy options for adoption of pasture-based livestock production as one of several agroecological approaches.

Surface soil characteristics arc of key importance in assessing the sustainability of agricultural management systems. We evaluated the factorial combination of nutrient source (inorganic, mixed organic + inorganic, and organic as broiler litter) and forage utilization (unharvested, low and high cattle grating pressure, and hayed) on soil organic matter during 12 yr of pasture management on a Typic Kanhapludult in Georgia. Nutrient source had very little effect on bulk density, soil organic C (SOC), and total soil N (TSN). Forage utilization greatly affected all soil properties, more so nearest the surface. For example, SOC at a depth of 0 to 3 cm under low grazing pressure was 47.6 g kg-1 and under haying was 28.8 g kg-1 (P < 0.00 1), while at 3 to 6 cm it was 20.1 and 14.9 g kg-1, respectively (P = 0.04), and at 6 to 12 cm it was 12.7 and 11.0 g kg-1, respectively (P = 0.59). Soil bulk density was inversely related to SOC. Total SOC (0-20 cm) plus surface residue C was 3.6 ± 3.6 Mg C ha-1 greater (mean ± standard deviation among six nutrient source it forage utilization comparisons) in the zone nearest shade and water sources than farther away. Sequestration of TSN in the surface 6 cm averaged 8 ± 8 kg N ha-1 yr-1 (mean ± standard deviation among three nutrient source comparisons) when hayed, 31 ± 15 kg N ha-1 yr-1 when left unharvested, and 74 ± 5 kg N ha-1 yr-1 when grazed by cattle with either low or high grazing pressure. These results indicate the large potential of well-managed grazing systems to improve the quality and functioning of soils in the southeastern United States. [ABSTRACT FROM AUTHOR]

Conservation management of degraded land has the potential to build soil fertility, restore soil functions, and mitigate greenhouse gas emissions as a consequence of surface soil organic matter accumulation. Literature from the southeastern United States was reviewed and synthesized to: (i) quantitatively evaluate the magnitude and rate of soil organic C (SOC) sequestration with conservation agricultural management; (ii) evaluate how conservation management affects surface SOC accumulation and its implications on ecosystem services; and (iii) recommend practical soil sampling strategies based on spatial and temporal issues to improve the detection of statistically significant SOC sequestration. Soil organic C sequestration was 0.45 ± 0.04 Mg C ha-1 yr-1 (mean ± standard error, n = 147, 20 ± 1 cm depth, 11 ± 1 yr) with conservation tillage compared with conventional tillage cropland. Establishment of perennial pastures sequestered 0.84 ± 0.11 Mg C ha-1 yr-1 (n = 35, 25 ± 2 cm depth, 17 ± 1 yr). Stratification of SOC with depth was common under conservation agricultural management and appears to be integrally linked to abatement of soil erosion, improvement in water quality, and SOC sequestration. Sampling of conservation management systems should ideally occur repeatedly with time in controlled and replicated experiments, but there is also an urgent need for chronosequence and paired-field surveys of SOC on working farms in the region to validate and expand the scope of inference of experimental results. Landowners in the southeastern United States have great potential to restore soil fertility and mitigate greenhouse gas emissions with the adoption of and improvement in conservation agricultural systems (e.g., continuous no-till, high-residue crop rotations, high organic matter inputs). [ABSTRACT FROM AUTHOR]

The article reports on the necessity of management systems to improve soil quality and regenerate ecological processes. It is indicated that conserving and restoring soil can supply soil productivity and sustain environmental quality. The Agricultural Research Service (ARS) of the U.S. Department of Agriculture created the Greenhouse Gas Reduction through Agricultural Carbon Enhancement network (GRACEnet) to study soil C sequestration and greenhouse gas emissions.

A number of scientists have named our age the Anthropocene because humanity is globally affecting Earth systems, including the soil. Global soil change raises important questions about the future of soil, the environment, and human society. Although many soil scientists strive to understand human forcings as integral to soil genesis, there remains an explicit need for a science of anthropedology to detail how humanity is a fully fledged soil-forming factor and to understand how soil change affects human well being. The development and maturation of anthropedology is critical to achieving land-use sustainabilitv and needs to be nurtured by all soil disciplines, with inputs from allied sciences and the humanities. The Soil Science Society of America (SSSA) has recently approved a cross-divisional Working Group on Soil Change, which aims to advance the basic and applied science of anthropedology, to facilitate networks of scientists, long-term soil field studies, and regional databases and modeling, and to engage in new modes of communications about human-soil relations. We challenge all interested parties, especially young scientists and students, to contribute to these activities and help grow soil science in the Anthropocene. [ABSTRACT FROM AUTHOR]