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Abstract Background Grazing lands provide numerous ecosystem services, including the capacity to store large amounts of soil carbon (C); however, our understanding of the factors affecting soil C responses to management is inadequate. Methods In this paper, we synthesized information about the impacts of grazing land management on soil C within the southeastern region of the United States. Results Most studies (68%) demonstrated that proper management increased soil C stocks with an average C accumulation rate of 1.4 Mg C ha−1 year−1. The remaining (32%) studies showed no effect of management on soil C. None of the studies reported negative impacts of management on soil C. The largest increase in soil C (8 Mg C ha−1 year−1) was associated with the conversion of cropland to pastureland while overseeding legumes into grass pastures resulted in the lowest C sequestration rates (0.2 Mg C ha−1 year−1). Conclusions Considering the rates of soil C accretion and the extensive area occupied by grazing lands, data in this synthesis confirm that the adoption of improved management practices can increase soil C sequestration in the southeastern United States. In addition, because most improved management practices can also have co‐benefits, they may be favorable for forage and livestock production and other ecosystem services.

Abstract Increasing demand for agricultural products is driving grassland management intensification with subsequent impacts on ecosystem services and disservices. Key questions related to grassland production as well as environmental and social concerns must be addressed to ensure sustainability. We propose a unified perspective, addressing numerous trade‐offs and synergies between grassland ecosystem services and disservices, and considering an array of ecological and human consequences associated with history and ongoing shifts in management strategies. Much of our discussion utilizes evidence from humid grasslands; however, our examples and recommendations have global implications for the future of grassland management. We characterize four categories of ecosystem services and disservices (provisioning, supporting, regulating, and cultural) provided by perennial grasslands that are extensively managed (low or no input, never cultivated) or intensively managed (high‐input, cultivated). We explore a range of potential outcomes following transition from extensive to intensive agroecosystems around the globe. Additionally, we suggest specific research priorities to better evaluate ecosystem services and disservices across management intensities. Finally, we highlight potential benefits of landscape mosaics that include grasslands across a continuum of extensive to intensive strategies.

Because of its adaptability to Florida’s environmental conditions and ability to produce viable seeds, pintoi peanut represents an interesting forage alternative for cow-calf producers in the state. This 5-page document provides current information on pintoi peanut for forage and livestock producers in Florida. Written by Joao M. D. Sanchez, Joao Vendramini, Maria L. Silveira, Jose C. B. Dubeux Jr., Lynn E. Sollenberger, and Philipe Moriel, and published by the UF/IFAS Agronomy Department, November 2020.

Abstract Litter decomposition, particularly from belowground pools, is a key process controlling the flow of nutrients and the sustainability of native and cultivated grazinglands. This study evaluated in situ belowground decomposition of saw‐palmetto (Serenoa repens [W. Bartram] Small) and bahiagrass (Paspalum notatum Flügge; BG), which corresponded to the predominant plant species in native and cultivated pastures in the southeastern United States. Belowground biomass decomposition (180 d) was estimated using the litterbag technique during the summer and winter. Season showed no effect on belowground decomposition. Decomposition followed a double exponential model (P ≤ .01) and was greater for BG than for native rangeland (NR) (−0.0008 and −0.0001 g g−1 d−1, respectively; P = .0035), resulting in less remaining material at the end of incubation for BG (74% compared with 93% for NR; P ≤ .002). Greater decomposition in BG occurred due to more favorable chemical composition than NR, namely greater initial N concentration (17 and 8 g kg−1 organic matter for BG and NR, respectively) and lower initial C/N ratio (29 and 65 for BG and NR, respectively), lignin/N ratio (13 and 54 for BG and NR, respectively), and C/P ratio (407 and 1,327 for BG and NR, respectively). Despite the differences in initial C/N ratios, remaining N was similar between BG and NR at end of incubation (96 and 84%, respectively; P = .3711). Land use intensification in grazinglands, in particular conversion of native rangelands to cultivated pastures, can have major impacts on belowground decomposition and on the biogeochemical cycle of nutrients in these ecosystems.

Abstract Increased grazing land management intensification through the selection of productive species and the use of N affects the amount and quality of C and N inputs to the soil. This study evaluated the short‐term impacts of litter quality on litter decomposition and C and N distribution among soil size–density fractions. A 168‐d litter bag mesocosm experiment and a 120‐d incubation study evaluated the decomposition of three perennial species [rhizoma peanut (Arachis glabrata Benth., RP), bahiagrass (Paspalum notatum Flügge; BG), and saw‐palmetto (Serenoa repens Bartr., SP)] on grazing land soils with contrasting C concentrations (3.4 and 18 g C kg−1; Buck Island Ranch and Ona, respectively). Soil did not affect litter decomposition. There was less remaining biomass at the end of incubation for RP and BG (58%) than SP (79%). Nitrogen immobilization occurred on SP litter, probably because of its high initial lignin/N and fiber‐bound N/N ratios (43 and 384 g kg−1 organic matter, respectively). Litter had no effect on soil C and N concentrations in size–density fractions; however, greater proportions of C and N (∼47 and 59%, respectively) were found in the light‐free fraction. Nitrogen addition promoted C and N accumulation in the mineral fraction. These results suggest plant litter chemical characteristics played a more important role on litter decomposition than soil C and N concentrations. Management intensification through changes in plant species and N fertilization had positive effects on C and N dynamics in coarse‐textured soils, with enhanced decomposability of cultivated forage species relative to native vegetation.

Soils in Florida may contain excess soil phosphorus (P) resulting from fertilizer, manure or biosolids applications. Excess P in soil does not damage soil fertility but can be transported from agricultural and urban areas either dissolved in water that drains away or as particulate matter (attached to soil particles) that travels with eroding soil. Increased P in water bodies is recognized as one of the major factors responsible for eutrophication-related decrease in water quality. Most soils have the capacity to retain excess P. However, soils with low capacity to retain excess P are abundant in Florida. The use of drinking-water treatment residuals (WTR) to control excess phosphorus (P) in soils with limited P adsorption capacity has been explored as a potential low-cost method by which to reduce phosphorus losses to surface waters and a discussion of these explorations is presented here. The target audience for this publication includes state agencies, like the Florida Department of Environmental Protection (FLDEP), and water management districts trying to control P pollution, and those interested in nutrient management for agricultural and environmental purposes. This 6-page fact sheet is a minor revision written by Jonathan D. Judy, Maria L. Silveira, Sampson Agyin-Birikorang, and George A. O’Connor, and published by the UF/IFAS Department of Soil and Water Sciences, June 2019. SL 300/SS513: Drinking-Water Treatment Residuals to Control Phosphorus in Soils (ufl.edu)

Land application of aluminum-based WTRs (Al-WTR) has been demonstrated to effectively control off-site phosphorus loss to surface and groundwater. Therefore, amending soil with Al-WTR could be a best management practice (BMP) to reduce off-site P losses from agricultural fields via runoff and leaching. However, environmental concerns that the aluminum and arsenic contents of Al-WTRs could negatively affect agricultural production and human health have led to the development of guidelines for land application of WTRs in Florida. This 8-page document explores possible effects of land-applying Al-WTR on the environment and recommends practices to minimize environmental or human and animal health risk. Target audiences include state agencies like FDEP, FDACS, water management districts trying to use Al-WTR to control P pollution, and those interested in nutrient management for environmental purposes. Written by Jonathan D. Judy, Maria L. Silveira, Sampson Agyin-Birikorang, and George A. O’Connor, and published by the UF/IFAS Department of Soil and Water Sciences, June 2019. SL 299/SS512: Are Alum-Based Drinking Water Treatment Residuals Safe for Land Application? (ufl.edu)

This four-page publication provides basic information about land application of biosolids to pastures and hayfields in Florida. The information contained in this document should be of interest to stakeholders, biosolids managers, students, and scientists interested in topics related to biosolids management practices and the potential benefits and risks associated with biosolid land application. Written by Maria L. Silveira, George A. O’Connor, and Joao M.B. Vendramini and published by the Department of Soil and Water Sciences.

Soil testing is the best tool for monitoring soil fertility levels and providing baseline information for cost-effective fertilization programs. But a major limitation is that it typically accounts for the plant-available nutrient pool present in the surface soil layer. Because of the extensive root system in some plants, plant analysis is a complement to the soil test to better assess the overall nutrient status of a perennial forage system, while revealing imbalances among nutrients that may affect crop production. This 4-page fact sheet was written by Maria L. Silveira and published by the UF Department of Soil and Water Science, June 2014. SL412/SS625: Soil and Plant Tissue Testing (ufl.edu)

Many forage-based livestock production systems in Florida are characterized by extensive grazing with minimal inputs of commercial fertilizer and supplemental feed. In these systems, adequate soil fertility conditions are essential to sustain forage production. If nutrients become deficient, pasture and animal performance is reduced, and the economic returns of livestock operations may decline. This 3-page fact sheet discusses the different nutrient pathways in grazing pastures to help producers better understand how to promote nutrient cycling and pasture sustainability. Written by Maria L. Silveira, Joao M. B. Vendramini, Hiran M. da Silva, and Mariana Azenha, and published by the UF Department of Soil and Water Science, January 2013. http://edis.ifas.ufl.edu/ss578

This study was designed to evaluate the effects of temperature on the potential leachable P pool and distribution of chemical P forms in a biosolids-amended soil. A P-deficient Spodosol was incubated with seven biosolids and inorganic P fertilizer at 20 and 32°C for 90 days. Amendments were applied to provide a total P concentration of 112 mg kg−1 soil, which correspond to a field application of ~224 kg P ha−1. Cumulative P mass leached during the 90 d study for any P source was

El secuestro de carbono en el suelo es el proceso de transformación del carbono del aire al carbono orgánico, almacenado en el suelo. A través del secuestro de carbono, los niveles de CO2 atmosférico pueden reducirse en la medida que los niveles de carbono orgánico del suelo aumentan. This 3-page fact sheet was written by Alejandra María Jimenez Madrid, José Trinidad Reyes Sandoval, and Maria L. Silveira, and published by the UF Department of Soil and Water Science, January 2012. SL363/SS564: Secuestro y Distribución de Carbono Orgánico del Suelo Bajo Diferentes Sistemas de Manejo de Pasturas (ufl.edu)

Phosphorus management in grazingland ecosystems represents a major challenge of agronomic and environmental importance. Because of the extensive acreage occupied by grazinglands, decisions concerning pasture fertilization and nutrient management in forage-based livestock systems are crucial to both farmers and regulatory agencies. The purpose of this paper is to provide an overview of the literature relevant to pasture P fertilization and the potential impacts on water quality. There continue to be uncertainties regarding interrelationships between pasture management and water quality issues. Despite the extensive body of literature on nutrient transport from grazinglands, limited information is available on the relationships between land use, transport potential, water management, and climatic conditions affecting nutrient losses at a watershed scale. As agriculture continues to modernize and intensify, public concerns about the impacts of plant nutrients on environmental quality will likely increase. Managing water quality protection and profitable agriculture will be a major challenge for the next generations.

SL309, a 6-page illustrated report by Maria L. Silveira, Randy Bateman, Joseph Walter, Jerry Sartain, Christa L. Kirby, and Pete Deal, presents the results of a study to evaluate P removal rates in different sod production systems in central and south Florida. Includes references. Published by the UF Department of Soil and Water Sciences, November 2009. SL 309/SS521: Phosphorus Removal Rates from Sod Production Systems (ufl.edu)

Revised! SL-237, a 15-page fact sheet by E.A. Hanlon, Rao Mylavarapu, C.L. Mackowiak, and M.L. Silveira, records changes in UF/IFAS’ bahiagrass fertilization and liming recommendations from 1990 through 2008 and summarizes efforts of the various work groups and committees. Includes references. Published by the UF Department of Soil and Water Science, January 2006. Revised August 2008 and April 2009. SL-237/SS456: Development of Bahiagrass Fertilization Recommendations: 1990–2008 (ufl.edu)

Revised! SS-AGR-63, a 4-page fact sheet by J. M. Vendramini, M. S. Silveira, J. D. Arthington, and A. R. Blount, provides basic information about forage testing procedures at the UF/IFAS Forage Extension Testing Laboratory, where to send samples, how to interpret the testing results, and how to collect a sample. Includes references. Published by the UF Department of Agronomy, February 2009. SS-AGR-63/AA192: Forage Testing (ufl.edu)

SL-249, a 6-page fact sheet by C. L. Mackowiak, A. R. Blount, E. A. Hanlon, M. L. Silveira, M. B. Adjei, and R. O. Myer, summarizes analysis practices and recommendations for bahiagrass fertilization for hay, sod or pasture systems. Includes recommended readings. Published by the UF Department of Soil and Water Sciences, April 2008. SL249/SS469: Getting the Most out of Bahiagrass Fertilization (ufl.edu)

SL-259, a 4-page fact sheet by M. L. Silveira, J. M. Vendramini, P. J. Hogue, and J. F. Selph, addresses important issues relative to fertilizer efficiency and suggests alternatives for reducing fertilizer use and reducing production costs for forage production. Published by the UF Department of Soil and Water Science, June 2008. SL259/SS483: Dealing With High Fertilizer Costs in Forage Production Systems (ufl.edu)

SL-251, a 3-page illustrated fact sheet by Diane Racine, Maria L. Silveira, and James W. Jawitz, provides basic guidelines for timely cleanup of petroleum spills or releases. It discusses categories of petroleum, reporting requirements, cleanup operations, soil removal, and land farming. Includes a flow chart and references. Published by the UF Department of Soil and Water Science, September 2007.

SL-252, a 3-page illustrated fact sheet by M.L. Silveira, J.M. Vendramini, L.E. Sollenberger, C.L. Mackowiak, and Y.C. Newman, explains the principles of tissue analysis, tissue sampling and handling, analysis and interpretation, and future directions. Published by the UF Department of Soil and Water Science, October 2007. SL252/SS475: Tissue Analysis as a Nutrient Management Tool for Bahiagrass Pastures (ufl.edu)