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Grazed pastures supporting ruminant livestock have not been well characterized for soil health condition. However, growing interest in holistic management of compromised watersheds suggests that grazing lands deserve more attention for their capacity to provide ecosystem services. Relatively little is known about how grazing management affects soil aggregation and other surface‐soil properties on private lands in the eastern United States. This study investigated the effects of land use (conventional‐till cropland, no‐till cropland, grassland, and woodland) and pasture management characteristics on soil aggregation, bulk density, sieved soil density, total soil N, and soil‐test biological activity on 31 private farms distributed across the western half of Virginia. Soil stability index followed the order (p < 0.05): conventional‐till cropland (0.60 mm mm−1) < no‐till cropland (0.78 mm mm−1) < woodland (0.85 mm mm−1) = grassland (0.89 mm mm−1). Surface soil characteristics improved with pasture age due to organic matter recycling from residual forage mass and animal excreta. Increases in total soil N and soil‐test biological activity helped create water‐stable aggregation and reduce soil bulk density. Soil stability index was optimized with moderate stocking rate of 0.5–1.1 Mg live weight ha−1. Stocking method did not affect soil aggregation or bulk density. Soil stability index declined with increasing N fertilization rate. Soil aggregation characteristics were generally not affected by organic amendment, quantity of hay fed on farm, or occasional hay harvest from pastures, likely because aggregation was high across management variables. Well‐managed grazed pastures in Virginia are creating desirable conservation agricultural land uses to protect watershed quality. Core Ideas: Soil aggregation under grazed pastures was stable and at a higher level than under cropland.Soil bulk density at 0‐ to 10‐cm depth declined with increasing level of conservation land use.Water‐stable mean‐weight diameter of soil aggregates had stronger association with soil‐test biological activity than with sand fraction.High soil stability index under mature grazed pastures may help mitigate against soil erosion and nutrient loss.Evidence was not supportive of rotational stocking as a practice to improve surface‐soil characteristics. [ABSTRACT FROM AUTHOR]

Soil texture and organic matter are considered overarching factors controlling a diversity of soil processes and properties. However, a more complete understanding of how these factors quantitatively affect other soil properties has been lacking due to either limited scope of land use and management conditions, confounding climate and environmental conditions with management, or narrow range of soil and management conditions. This study evaluated the strength of associations of sand and total soil N concentrations with soil physical, chemical, and biological properties and processes from 310 surface‐soil (0–10‐cm depth) samples (87% Ultisols, 4% Inceptisols, and ≤3% each of Alfisols, Spodosols, Entisols, and Histosols) collected under conventional‐till and no‐till cropland, grassland, and woodland in four physiographic regions of North Carolina. Sand concentration was most strongly associated with dry‐stable mean‐weight diameter (MWD), MWD product, and sieved soil density (|r| > 0.63, p < 0.001). Total soil N concentration was most strongly associated with particulate organic C and N and soil water content at water‐holding capacity (|r| > 0.74, p < 0.001). Soils under unfertilized woodlands deviated the most from general associations, suggesting that organic matter quality could be unique, and requires further investigation. Overall, sand concentration associated more closely with soil physical properties and total soil N concentration associated closely with both soil physical and biogeochemical properties. Soil chemical properties were only weakly associated with either property. This study suggests that soil texture and organic matter would be complementary, additional properties in holistic soil health assessments that already included routine soil chemical analyses. Core Ideas: Soil texture strongly associated with dry‐stable aggregation but weakly associated with water‐stable aggregation.Total soil N strongly associated with particulate organic C and N and soil water content at water‐holding capacity.Sand and total soil N concentrations were strong combined indicators of bulk density, sieved soil density, and cation‐exchange capacity.Sand and total soil N concentrations were unique soil health indicators in addition to routine soil chemical propertiesSieved soil density could be a relatively rapid and inexpensive indicator that combines the influences of soil texture and organic matter. [ABSTRACT FROM AUTHOR]

Contemporary agricultural systems can be generalized as highly specialized operations that are fueled by mechanization; supplied with external nutrients to maximize production; crops protected by petrochemicals to fight against weed, disease, and insect pressures; and livestock protected by therapeutics to ward off virus and bacterial infections when managed in confinement. Such specialized systems have led to low levels of diversity, elevated environmental risks from contamination, loss of soil organic matter, ecological instability, and limited adaptability to climate change. More diversified farming systems are possible, but research required to characterize them in a holistic manner as an alternative to contemporary, specialized systems remains challenging to fund and sustain over time, primarily because they require more labor, management skills, and accessible markets to achieve additional ecological, environmental, and social goals. We share some perspectives as to (1) how specialized systems became the norm and (2) what changes could be made to reverse some ecological risks and environmental declines associated with specialization, acknowledging there is no panacea. Strong evidence exists for perennial forages to restore soil organic carbon (C) and nitrogen, but system‐level analyses of the net balance in greenhouse gas emissions remain to be characterized in the myriad of potential integrated crop–livestock systems that might be deployed across the diversity of edaphic, environmental, and socio‐economic conditions. We suggest there are abundant opportunities for more sustainable agricultural production to sequester soil organic C, reduce greenhouse gas emissions, and develop more climate‐resilient agricultural systems that will be needed in a future dominated by climate change issues. Core Ideas: Forage‐based crop rotations are a proven practice for conserving nutrients and improving soil health.Diversity on farms in the United States is low and could be enhanced with integrated crop–livestock systems.Structural barriers to integrated crop–livestock systems are present but could be overcome. [ABSTRACT FROM AUTHOR]

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]

Biologically active and intermediately labile fractions of soil organic matter are important features of conservation agricultural management systems. Depth distribution of soil‐test biological activity (STBA) and particulate organic carbon (C) and nitrogen (N) were characterized under cropland, grassland, and woodland across 25 research stations in North Carolina. Most (87%) of the 310 fields sampled were on Ultisols (udults or aquults). Variation in STBA in the surface 30‐cm of soil was controlled primarily by land use and to a lesser extent by soil texture and physiographic region. Baseline concentrations of STBA and particulate organic C and N at 30‐cm depth were relatively narrowly constrained compared with contents in the 0‐ to 10‐cm depth. Root‐zone enrichment (i.e., total minus baseline contents) of STBA (mean ± standard error; kg CO2–C ha−1 3 d−1) followed the order: conventional‐till cropland (194 ± 17) < no‐till cropland (274 ± 26) < woodland (421 ± 17) < grassland (537 ± 15) across locations. Proportion of root‐zone enrichment of soil organic C as particulate organic C was 43 ± 2%. Root‐zone enrichment of particulate organic C (Mg C ha−1) followed the order: conventional‐till cropland (3.8 ± 0.6) < no‐till cropland (8.7 ± 0.8) < grassland (14.1 ± 0.5) < woodland (16.3 ± 0.6) across locations. The C:N ratio of root‐zone‐enriched particulate organic matter was greater under woodland than under other land uses likely because of N input limitations. Conservation land uses increased root‐zone enrichment of these active and intermediately labile fractions independent of soil types and regions in the state. Core Ideas: Root‐zone enrichment calculations were sensitive to conservation land uses.As a proportion of total root‐zone enrichment of soil‐test biological activity (STBA), 68 ± 7% occurred in the 0‐ to 10‐cm depth.Grasslands and woodlands had greater root‐zone enrichment of particulate organic C and N than croplands.No‐till cropland had greater root‐zone enrichment of STBA and particulate organic C and N than conventional‐till cropland.Greater C:N ratio of root‐zone‐enriched particulate organic matter under woodlands may have been from lack of N input. [ABSTRACT FROM AUTHOR]

Soil aggregation is considered a key indicator of soil health to protect soil against erosion, enhance organic C storage, and offer habitat for soil organisms. Various methods to assess aggregation may change interpretations of management, and therefore should be cross‐calibrated. We assessed the impact of initial sieve opening size (8 or 4.75 mm) prior to determination of dry‐stable and water‐stable mean‐weight diameter (MWD) from two fine‐textured soils—a Rhodic Hapludox from São Paulo, Brazil and a Rhodic Kanhapludult from North Carolina, United States. Both soils were subjected to management expected to alter surface soil conditions. As expected, initial sieving through 8 mm led to greater dry‐stable MWD (3.37 ± 0.60 mm) than initial sieving through 4.75 mm (1.94 ± 0.28 mm). However, soil stability index (water‐stable MWD/dry‐stable MWD) was not affected by initial sieve size opening (0.56 ± 0.13 mm mm−1 under both initial sieve openings). Management interpretations were consistent with both approaches as well, and in particular to detect the strong depth effect on water‐stable MWD (i.e., declining with depth). Water‐stable macroaggregates had 32% ± 25% greater C concentration than microaggregates; similarly under both initial sieving conditions. Soil stability index when initially sieved through 4.75 mm was highly associated with aggregate stability of 1–2‐mm sized dry aggregates, which is a more common procedure. We conclude that passing soil through a screen with 4.75‐mm openings to conduct a diversity of soil analyses can be appropriate for obtaining reasonable estimates of and interpretations about surface soil aggregation. Core Ideas: Soil stability index is water‐stable divided by dry‐stable mean‐weight diameter of whole soil.Soil stability index was similar whether soil was initially sieved through 8 or 4.75 mm.Water‐stable mean‐weight diameter and soil stability index declined with soil depth.Water‐stable macroaggregates had 32% ± 25% greater soil organic C than microaggregates. [ABSTRACT FROM AUTHOR]

Spatial variation in soil properties is often considered significant across broad geographical regions due to soil formation factors. However, fine‐scale variations might also be significant. This study was conducted with the original intent of assessing how simple and complex mixtures of annual forages might be used to renovate perennial pastures. Private farmers in the Flatwoods, Piedmont, and Blue Ridge Major Land Resource Areas of North Carolina tested annual forages to renovate tall fescue pastures. Soil was sampled in multiple random locations in each field at depths of 0–6, 6–12, and 12–20 cm at the beginning and ending of a 3‐yr annual forage evaluation. Relative variation among five components (year of sampling [n = 2], physiographic region [n = 3], annual forage treatment [n = 2], soil depth [n = 3], and random variation from pseudoreplicates [n = 3 in 2015 and n = 5 in 2018]) was assessed for four soil physical, 10 soil biological, and 16 soil chemical properties. Soil chemical properties were mostly affected by physiographic region (47 ± 26% of total variation) and soil depth (33 ± 18%), soil biological properties were mostly affected by soil depth (63 ± 25%) and random pseudoreplication (14 ± 6%), and soil physical properties were equally affected by pseudoreplication (35 ± 21%), physiographic region (32 ± 18%), and soil depth (29 ± 22%). The type of annual forage had no discernible effect on soil properties, even the most biologically active. A diversity of spatial variations was important, suggesting that regional‐level ecological investigations require careful attention to an appropriate sampling design considering multiple factors. Core Ideas: Soil properties were unaffected by annual forage species diversity during pasture renovation.Chemical properties varied mostly due to physiographic region (separation of ∼300 km).Biological properties varied mostly due to soil depth (separation of ∼10 cm).Physical properties varied equally among region, pseudoreplication, and depth.Net N mineralization was best predicted by a simple, rapid, and robust test of biological activity. [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]

Soil erosion is a major constraint to agricultural sustainability. Land management that protects soil from water erosion can be assessed from the fraction of aggregates stable upon water immersion. Conservation management with minimal soil disturbance is known to enhance water‐stable aggregation, but how annual vs. perennial vegetative cover affects soil biological activity and aggregation from soils varying in texture remains relatively unexplored. This study assessed the effects of long‐term conventional‐till and no‐till cropland, grassland, and woodland on dry‐stable and water‐stable mean‐weight diameter (MWD) from 25 research stations across North Carolina. Soil clay concentration varied from 36 to 279 g kg–1 and sand concentration varied from 392 to 904 g kg–1 (5–95% distribution). Across locations, water‐stable MWD followed the order: conventional‐till cropland (0.64 mm) < no‐till cropland (0.87 mm) < woodland (1.12 mm) = grassland (1.15 mm). Soil stability index (i.e., water‐stable MWD/dry‐stable MWD) followed a similar order: conventional‐till cropland (0.59 mm mm–1) < no‐till cropland (0.76 mm mm–1) < grassland (0.92 mm mm–1) = woodland (0.96 mm mm–1). Although water‐stable MWD was positively associated with clay concentration (r =.50, p <.001, n = 310), soil‐test biological activity had the strongest association with water‐stable MWD (r =.80). Soil‐test biological activity reflected biological manipulation of surface‐concentrated organic matter, as mediated by conservation land uses. This study revealed the large impact of surface organic C and N resources on water‐stable aggregation through soil biological manipulations interacting across a textural gradient. Core Ideas: Conservation land uses of no‐till cropland, grassland, and woodland improved soil aggregation characteristics.Soil stability index discerned conservation land use impacts across a soil texture gradient.Soil aggregation characteristics were not different between grasslands and woodlands.Soil‐test biological activity and sand were strongly associated with soil aggregation characteristics. [ABSTRACT FROM AUTHOR]

Conservation agricultural systems have a long history of development and use in the southeastern United States, but they are still not the norm on the landscape. Literature from the region suggests that a diversity of soil properties can be improved with cover cropping and conservation tillage, but results are not always consistent. Our objectives were to (a) review recent research on conservation tillage and cover cropping in the region and (b) compile and synthesize recent data from a diversity of farms along a conventional to conservation gradient. As part of recent on‐farm trials focused on soil N availability, we analyzed soil organic C and N fractions and routine soil nutrient characteristics from a total of 196 fields in corn (Zea mays L.), wheat (Triticum aestivum L.), and barley (Hordeum vulgare L.) production in three physiographic regions of the Coastal Plain (n = 71 fields), Piedmont (n = 77 fields), and Appalachians (n = 48 fields) in North Carolina, South Carolina, Pennsylvania, and Virginia. These data allowed us to establish first estimates of threshold optima for soil organic C and N fractions and other inorganic nutrients. On‐farm data confirmed the literature review that conservation tillage resulted in greater stratification of soil organic C and N and nutrient concentrations. Soil health improvement could be inferred along the gradient from inversion tillage to no tillage without cover cropping to no tillage with cover cropping. This collection of recent literature and on‐farm data can be a useful starting point for establishing target limits and assessing soil health conditions on farms in the region. Core Ideas: There was significant improvement in soil organic C and N and inorganic nutrients with no‐till and covers.Soil health improved with adoption of no‐till compared with inversion tillage.There was weak evidence for soil health improvement with multi‐species covers compared to single species.Soil‐test biological activity and net N mineralization are effective indicators of soil health. [ABSTRACT FROM AUTHOR]

The cover image is based on the Original Article Farming with forages can reconnect crop and livestock operations to enhance circularity and foster ecosystem services by Alan J. Franzluebbers et al., https://doi.org/10.1111/gfs.12592. [ABSTRACT FROM AUTHOR]