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Biodiversity impacts are rarely included in systems analyses of livestock production. We piloted two approaches toward quantifying biodiversity impacts, pressure‐state‐response (PSR) and potential species loss (PSL), at a cow–calf operation in Florida for which extensive environmental data were available. Using these approaches, we compared livestock production on two vegetation types, semi‐native pasture (SNP) and improved pasture (IMP), and we found fewer deleterious effects on biodiversity associated with SNP (characterized by low stocking rates and no fertilizer) than with IMP, as evidenced by a lower PSL and greater biotic integrity under PSR. Both approaches agreed in the direction of the outcome, but we argue that, when possible, they should be applied complementarily to inform both absolute and per‐unit product biodiversity impacts of livestock production. This research demonstrates how to incorporate biodiversity into life‐cycle perspectives of livestock sustainability assessments when data availability varies, supporting the expansion of multi‐metric, holistic evaluations that are absent from most livestock system analyses. [ABSTRACT FROM AUTHOR]

Isolated, seasonal wetlands within agricultural landscapes are important ecosystems. However, they are currently experiencing direct and indirect effects of agricultural management surrounding them. Because wetlands provide important ecosystem services, it is crucial to determine how these factors affect ecological communities. Here, we studied the long‐term effects of land‐use intensification, cattle grazing, prescribed fires, and their interactions on wetland plant diversity, community dynamics, and functional diversity. To do this, we used vegetation and trait data from a 14‐year‐old experiment on 40 seasonal wetlands located within seminatural and intensively managed pastures in Florida. These wetlands were allocated different grazing and prescribed fire treatments (grazed vs. ungrazed, burned vs. unburned). Our results showed that wetlands within intensively managed pastures have lower native plant diversity, floristic quality, evenness, and higher nonnative species diversity and exhibited the most resource‐acquisitive traits. Wetlands embedded in intensively managed pastures were also characterized by lower species turnover over time. We found that 14 years of cattle exclusion reduced species diversity in both pasture management intensities and had no effect on floristic quality. Fenced wetlands exhibited lower functional diversity and experienced a higher rate of community change, both due to an increase in tall, clonal, and palatable grasses. The effects of prescribed fires were often dependent on grazing treatment. For instance, prescribed fires increased functional diversity in fenced wetlands but not in grazed wetlands. Our study suggests that cattle exclusion and prescribed fires are not enough to restore wetlands in intensively managed pastures and further highlights the importance of not converting seminatural pastures to intensively managed pastures. Our study also suggests that grazing levels applied in seminatural pastures maintained high plant diversity and prevented tree and shrub encroachment and that in the absence of grazing, prescribed fire became crucial to maintaining higher species evenness. [ABSTRACT FROM AUTHOR]

Plant–plant interactions influence community assembly and species responses to environmental change. However, species interactions are complex phenomena influenced by context and scale. We conducted a one-year replacement experiment between two grasses in subtropical grasslands (native Axonopus fissifolius and non-native Paspalum notatum) in central Florida, USA. We evaluated interactions between these species at three ecological scales, 'pairwise interactions,' 'patch' (33 cm × 33 cm), and 'plot' (1 m x 3 m) and along a gradient (15 levels) of increasing non-native and decreasing native plot ground cover within enclosures in semi-native pastures. We transplanted 18 individuals of each species per plot (18 × 30 plots = 1080 plants in total) in a 2 × 2 design intersecting direct pairwise interactions (additional transplanted neighbor: absent/present) with recipient patch type (Axonopus fissifolius/Paspalum notatum). Leaf length, leaf number, and plant biomass were measured at the beginning and the end of the experiment along with soil nutrients and pH at patch level. Over 92% of the transplants survived. We observed an interactive effect between patch type (non-native vs. native dominated) and plant abundance at plot level on plant performance, suggesting that indirect effects at larger spatial scales can influence effects at smaller scales. Surprisingly, both species exhibited enhanced performance with increasing abundance of the non-native species at plot level. We discuss several mechanisms explaining these indirect effects including Paspalum notatum-induced changes in soil pH, soil feedbacks from the soil microbial community, preconditioning effects of the native species on the recipient soil, and positive density dependence effects after transplantation. [ABSTRACT FROM AUTHOR]

Aims: The stress gradient hypothesis predicts that competition will be important in productive environments while facilitation will be common in environments with high stress or consumer pressure. However, abiotic stress and grazing may vary independently and even occur simultaneously. Here we examine the outcome of plant interactions in grazed wetlands where consumer pressure and abiotic stress occur concurrently. We hypothesized that cattle grazing and microhabitat would alter the outcome of plant interactions. Given that wetland edges are drier and less productive than wetland centers we expected that facilitation would be greatest in drier wetland edges due to greater abiotic stress regardless of cattle presence. Location: Archbold Biological Station's Buck Island Ranch (BIR), south‐central Florida, USA (27°09′ N, 81°11′ W). Methods: We conducted an experiment for two growing seasons in ten wetlands, five exposed to cattle grazing and five fenced. Two wetland obligate plants were included (Panicum hemitomon and Alternanthera philoxeroides), and plots were assigned to three treatments (a) all neighbors removed; (b) all neighbors removed except Juncus effusus, a dominant, unpalatable plant; and (c) all neighbors intact (control), in both wetland centers and edges. Differences in survival, change in height and number of leaves were assessed. Results: In ungrazed wetlands, plant survival was higher in wetland edges vs centers, while it did not differ between microhabitats in grazed wetlands. Survival in wetland edges was further increased by the presence of Juncus effusus. Positive interactions under grazed conditions were clear when plant height was assessed, but negative interactions affected leaf production in both ungrazed and grazed wetlands. Conclusions: Grazing interacts with wetland microhabitat to alter plant survival. Facilitative interactions on plant height were apparent in grazed wetlands. Understanding how plant interactions change under different biotic and abiotic contexts is important for informing ecosystem restoration and management. [ABSTRACT FROM AUTHOR]

Wetlands in agroecosystems provide multiple ecosystem services, including provisioning services such as forage production. Here, we examine how pasture management intensity (semi‐natural pastures vs. highly managed pastures (fertilized, heavily drained, planted with productive grasses), cattle exclusion (grazed vs. fenced), prescribed fire (burned vs. unburned), and their interactions affect provisioning services provided by small, isolated, and seasonally flooded wetlands in subtropical pastures and rangelands. We used a replicated, full‐factorial experiment on 40 seasonally flooded wetlands located in Florida (USA), and measured standing plant biomass and annual net primary productivity in each wetland. Biomass was sorted by species to calculate species abundance of palatable and unpalatable plants. We used general linear mixed models to evaluate the effect of treatments and their interactions on biomass quantity, plant tissue nutrients (% C, % N, and % P), and forage nutritive value (using in vitro organic matter digestibility). Plant standing biomass and productivity were greatest in wetlands embedded in highly managed pastures, but in grazed wetlands, a large proportion of this biomass was unpalatable to cattle. Excluding cattle from wetlands in highly managed pastures increased productivity, standing biomass, and the amount of palatable species (~6.3 t/ha) compared to grazed wetlands (~3.3 t/ha), especially when these wetlands were also exposed to prescribed fire. Total P in plant tissue was consistently higher in wetlands within highly managed pastures, but total N responses to treatments varied between years. In vitro digestibility was higher in vegetation from wetlands within highly managed pastures, but not in fenced wetlands despite the higher amount of palatable species, suggesting that palatability and digestibility were decoupled. Subtropical wetlands in agroecosystems provide substantial provisioning services, and our study suggests that targeted management can increase these services. However, the pasture type surrounding a wetland interacts with grazing and fire management to affect provisioning services. We propose that fencing off selected wetlands (specifically in highly managed pastures) followed by low‐intensity grazing with adequate resting periods could benefit ranchers and have less persistent impacts on this ecosystem. [ABSTRACT FROM AUTHOR]

Pasture management intensity, livestock grazing and prescribed fire are three widespread agricultural practices that affect small, isolated wetlands, but few studies have investigated their individual and interactive effects. Pasture management intensity refers to the degree of human alteration of grassland, ranging from intensively managed pastures planted with introduced forage, fertilizer/lime additions and artificial drainage to semi-natural pastures with mixed native and non-native vegetation, no fertilizer/lime additions and little or no artificial drainage., We examined individual and interactive effects of these three agricultural practices on individual, isolated wetlands using a replicated, full-factorial experiment on 40 entire wetlands in south Florida, USA. Wetlands were embedded in two pasture management intensities: intensively managed and semi-natural., After three years of treatment initiation, vegetation of wetlands released from grazing and unburned embedded in semi-natural pastures had significantly lower evenness and coefficient of conservatism scores compared to wetlands released from grazing and burned, grazed unburned wetlands and grazed burned wetlands in the same pasture management intensity. For wetlands embedded in intensively managed pastures, evenness and coefficient of conservatism scores did not differ among treatments., Release from grazing increased abundance of the native, weedy herb, Eupatorium capillifolium., Grazing interacted with prescribed fire to affect shrub abundance and non-native richness; relative abundance of shrubs and non-native richness were greater in wetlands released from grazing and burned and did not differ among burn treatments in grazed wetlands. Interactive effects, especially three-way interactions, were uncommon and not as important as differences between the two pasture management intensities., Synthesis and applications. Vegetation diversity and floristic quality of wetlands embedded in intensively managed pastures resisted common restoration management techniques such as release from grazing and prescribed fire, at least in the short term. In contrast, removing all top-down disturbances from wetlands embedded in semi-natural grasslands can negatively affect vegetation species diversity and floristic quality. Future studies should examine how intensity and seasonality of grazing and prescribed fire affect wetland vegetation, and track long-term responses to evaluate lag effects. [ABSTRACT FROM AUTHOR]

The invasive Pomacea maculata (= Pomacea insularum) (Perry) (Island Apple Snail) is becoming increasingly abundant in the southeastern US with potentially detrimental effects on wetland vegetation and water quality. Here, we investigate the association of plant-community structure and aquatic-predator abundance with Island Apple Snail invasion in seasonal wetlands on a cattle ranch in south-central Florida. We found a negative correlation between Island Apple Snail abundance and abundance of its preferred forage species, raising concerns that the snail may have already altered plant communities in these seasonal wetlands. We also found a negative correlation between Island Apple Snail abundance in wetlands and distance to the nearest ditch. In a snail-growth experiment, we found a negative effect of species evenness and a positive effect of total vegetation cover on Island Apple Snail weight gain. To understand Island Apple Snail invasion success in seasonal wetlands, more research is needed on the relative importance of landscape- versus local-scale wetland characteristics and how resources such as preferred forage versus egg-laying sites affect snail-population growth. [ABSTRACT FROM AUTHOR]

• The teabag index (TBI) was adopted to quantify subtropical wetland decomposition. • Land-use intensification, grazing, and fire interactively affected decomposition. • Hydrology and climate contributed to spatial–temporal variation in decomposition. • TBI is a useful indicator to inform wetland ecosystem service management. Understanding how global change drivers and their interactions affect decomposition in wetlands embedded in agricultural landscapes remains challenging, especially in tropical and subtropical biomes, which are disproportionately important for global carbon cycling yet with high uncertainties. In a long-term whole-ecosystem experiment, we used a widely-adopted indicator of decomposition, the Teabag Index (TBI), to investigate individual and interactive effects of surrounding land-use intensity, cattle grazing, and prescribed fire on seasonal wetland decomposition (i.e., decay rate k , and stabilization factor S) in an exemplar subtropical landscape in central-south Florida, USA. We ask: (1) How do land-use intensity and management practices affect the decomposition in seasonal wetlands? (2) How does wetland decomposition vary with hydrological gradient and seasonal climatic condition? (3) What are the dominant direct and indirect pathways through which land-use intensity and management practices affect wetland decomposition? Our results showed that, overall, surrounding land-use intensity exerted much stronger effects on litter decomposition compared to grazing and prescribed fire, and cattle grazing reduced decomposition rate k. There was a complex three-way interaction among land-use intensity, grazing and fire on the stabilization factor S – a proxy related to carbon sequestration potential. Grazing-fire interactive effects on S only existed in wetlands embedded in intensively-managed landscapes, where grazing reduced S in burned wetlands but did not affect S in unburned wetlands. Decay rate k showed profound temporal variation primarily driven by seasonal climatic conditions (especially precipitation), whereas S varied spatially along the hydrological gradient. Our structural equation modeling (SEM) analyses further revealed that effects on k were also indirectly manifested through changes on soil C/N, C/P, and pH, while effects on S were manifested through alterations in soil C/P ratio, pH, soil nutrients and water content. Our TBI results suggest that anthropogenic environmental changes, including land-use intensification, livestock introduction and fire suppression, could compromise carbon sequestration potential in tropical and subtropical seasonal wetlands. Our research highlights the importance of considering landscape context in wetland management and demonstrates the use of TBI as an indicator to quantify and inform combinations of land management and agricultural practices could conserve wetlands and sustain their vital functions and services, especially from the lens of promoting carbon storage and nutrient retention services. [ABSTRACT FROM AUTHOR]

Humid, subtropical grazing lands utilized for cattle production are significant agroecosystems that are important for economic production, global food security, and biodiversity. Prescribed fire, an important management tool, is used for controlling woody plant encroachment, maintaining wildlife habitat, and stimulating forage regrowth. Fire also interacts with grazing to maintain grassland structure and heterogeneity. Understanding this fire-grazing interaction is important to producers because spatio-temporal cattle behavior has been linked to both livestock production and environmental impact through patterns of pasture utilization. The goal of the study was to understand how two fire regimes affected spatial and temporal grazing behavior, including grazing intensity, grazing evenness, and circadian and seasonal grazing patterns. A randomized block design experiment was established in 2017 with 16 pastures (16 ha each), at Archbold Biological Station's Buck Island Ranch in FL, USA. We examined two prescribed fire management techniques, one represented the prevailing practice of the region with prescribed fire applied to entire pastures (full burn = FB), and the other 'alternative' regime applied patch-burn (PB), in which one-third of a pasture was burned each year. Here we present results from the first year of the study, after the first patch-burns and the full burns were implemented. Global Positioning System data loggers on cows recorded 5-min location fixes to track cows and cattle grazing behavior was inferred based on distances between GPS locations. Cattle behavior was significantly different in PB vs. FB pastures. Over a year with five grazing periods, cattle spent on average 38% more time grazing in burned vs unburned patches within PB pastures. PB burned patches were also grazed with a more even spatial distribution compared to unburned patches. In contrast, in FB pastures, cattle grazing intensity and evenness were similar across the entire pasture. Time of day, temperature, season, and fire treatment all had small effects on the circadian cattle grazing patterns. Our study suggests that PB can be a management tool to manipulate cattle behavior in humid subtropical grazinglands, with potential implications for pasture utilization and beef production, carbon and nutrient cycling, and wildlife habitat. • Patch-burn grazing (PBG) altered cattle behavior in subtropical grazing lands. • In PBG, cattle spent 38% more time and grazed more evenly in burned patches. • In full-burns, grazing time and evenness were similar across the entire pasture. • PBG can increase utilization and heterogeneity in subtropical grazing lands. [ABSTRACT FROM AUTHOR]

• Phosphorus decreased within a year in highly altered wetlands with grazing and fire. • After a year, phosphorus and ammonia decreased in highly altered wetlands with fire. • After 6 years, only ammonia decreased with grazing removed and fire. • In a lab experiment, plants & detritus released phosphorus & nitrogen after burning. Small, isolated, depressional wetlands increasingly exist in developed landscapes and are highly vulnerable to hydrologic alterations and eutrophication. Globally, grazing lands contain a significant number of these wetlands, and the practices of grazing, prescribed fire and fertilizing have all been shown separately to influence wetland nutrient dynamics. However, wetlands are often exposed to a combination of these practices and the interactive effects have yet to be fully elucidated. The purpose of this study was to examine the effects of pasture management, grazing, and fire on water quality in isolated wetlands on a subtropical ranch in South-Central Florida. We used a factorial experiment on 40 whole wetland ecosystems manipulating grazing (fenced or not) and fire (burned or not) in two pasture types (intensely managed and semi-native). Grab samples of water were collected over 8 years, including one pre-treatment year, at peak growing season, in all wetlands and analyzed for nitrogen and phosphorous. In addition, we conducted a laboratory experiment to simulate the effect of a prescribed burn on water quality using live plant tissue, detritus, and soil taken from grazed and fenced wetlands to investigate the interactions of these practices on short-term responses of water quality. In the field experiment, after one year of experimental treatments, wetlands exposed to both grazing and prescribed burns had relatively low phosphorous in water in intensely managed pastures. After multiple years of treatment only ammonia was reduced with burning and fencing in both pasture-types. In the lab experiment, simulated burning caused a pulse release of phosphorous and a reduction of nitrogen due to volatilization of both live plant tissue and detritus, but the magnitude was influenced by grazing and pasture-type. This study of rangeland management on wetland water quality demonstrates the effect of these practices, especially prescribed burns, on improving nutrient release in agricultural wetlands and shows that management effects on nutrient release varies with historical land use and over time. [ABSTRACT FROM AUTHOR]

Intensification, the process of intensifying land management to enhance agricultural goods, results in "intensive" pastures that are planted with productive grasses and fertilized. These intensive pastures provide essential ecosystem services, including forage production for livestock. Understanding the synergies and tradeoffs of pasture intensification on the delivery of services across climatic regions is crucial to shape policies and incentives for better management of natural resources. Here, we investigated how grassland intensification affects key components of provisioning (forage productivity and quality), supporting (plant diversity) and regulating services (CO 2 and CH 4 fluxes) by comparing these services between intensive versus extensive pastures in subtropical and temperate pastures in the USDA Long-term Agroecosystem Research (LTAR) Network sites in Florida and Oklahoma, USA over multiple years. Our results suggest that grassland intensification led to a decrease in measured supporting and regulating services, but increased forage productivity in temperate pastures and forage digestibility in subtropical pastures. Intensification decreased the net CO 2 sink of subtropical pastures while it did not affect the sink capacity of temperate pastures; and it also increased environmental CH 4 emissions from subtropical pastures and reduced CH 4 uptake in temperate pastures. Intensification enhanced the global warming potential associated with C fluxes of pastures in both ecoregions. Our study demonstrates that comparisons of agroecosystems in contrasting ecoregions can reveal important drivers of ecosystem services and general or region-specific opportunities and solutions to maintaining agricultural production and reducing environmental footprints. Further LTAR network-scale comparisons of multiple ecosystem services across croplands and grazinglands intensively vs extensively managed are warranted to inform the sustainable intensification of agriculture within US and beyond. Our results highlight that achieving both food security and environmental stewardship will involve the conservation of less intensively managed pastures while adopting sustainable strategies in intensively managed pastures. • Intensification did not increase forage productivity in subtropical pastures. • Intensification increased forage productivity in temperate pastures. • Intensification reduced supporting and regulating services in pastures. • Intensification reduced CO 2 sink capacity and increased CH 4 emissions of subtropical pastures. • Intensification increased the global warming potential associated with C fluxes in pastures. [ABSTRACT FROM AUTHOR]

The accumulation of soil legacy phosphorus (P) due to past fertilization practices poses a persistent challenge for agroecosystem management and water quality conservation. This study investigates the spatial distribution and risk assessment of soil legacy P in subtropical grasslands managed for cow-calf operations in Florida, with two pasture types along the intensity gradient: improved vs semi-native pastures. Soil samples from 1438 locations revealed substantial spatial variation in soil legacy P, with total P concentrations ranging from 11.46 to 619.54 mg/kg and Mehlich-1 P concentrations spanning 0.2-187.27 mg/kg. Our analyses revealed that most of the sites in semi-native pastures may function as P sinks by exhibiting positive Soil P Storage Capacity (SPSC) values, despite having high levels of soil total P. These locales of higher SPSC values were associated with high levels of aluminum, iron, and organic matter that can adsorb P. In addition, our results from spatial random forest modelling demonstrated that factors including elevation, soil organic matter, available water storage, pasture type, soil pH, and soil order are important to explain and predict spatial variations in SPSC. Incorporating SPSC into the Phosphorus Index (PI) spatial assessment, we further determined that only 3% of the study area was considered as high or very high PI categories indicative of a significant risk for P loss. Our evaluation of SPSC and PI underscores the complexity inherent in P dynamics, emphasizing the need for a holistic approach to assessing P loss risk. Insights from this work not only help optimize agronomic practices but also promote sustainable land management, thus ensuring the long-term health and sustainability of grass-dominated agroecosystems., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Jiangxiao Qiu reports financial support was provided by Florida Department of Agriculture and Consumer Services. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

In the USA, the United States Department of Agriculture (USDA) Natural Resource Conservation Service (NRCS) has restored millions of acres of wetlands through its Wetland Reserve Easement (WRE) programs. However, few quantitative studies have explored whether WREs have enhanced wetland hydrology and wetland plant communities. Additionally, USDA Compatible Use Permits for cattle grazing and other management practices are sometimes issued for WREs, but little is known about potential benefits/detriments of such practice on the success of wetland restoration. In this study, we tested if hydrological restoration of previously drained species poor pastures increased water depth and hydroperiod. Restoration involved plugging key ditches, adding water control structures and a berm. We also tested if hydrological restoration increased plant diversity (alpha and beta), floristic quality (using coefficient of conservatism) and increased the cover of wetland species (using species wetland status). Finally, we tested if cattle grazing had an effect on the success of restoration by comparing grazed plots to fenced plots. We studied two conservation easements (a total of 748 acres) located on semi-native pastures in central Florida, USA. We monitored vegetation using permanent transects stratified by vegetation type before (2004-2005) and after (2012) the restoration (2008). We assessed wetland hydroperiod using groundwater wells set up in 2003 and located within and outside the boundaries of these two easements. We used linear mixed models and multivariate analyses to compare vegetation and hydroperiods pre- and post-restoration. Number of flooded days increased following restoration in one of the easements, but we did not detect significant changes in hydrology in the other easement. Floristic quality, beta diversity and cover of obligate wetland species increased in both conservation easements and in most vegetation types. These vegetation changes were likely due to restoration activities since annual rainfall was not significantly different pre- and post-restoration. Cattle grazing did not have a negative or positive effect on the success of restoration, nor did we detect any positive effect of grazing on the success of restoration. Overall, our study shows that hydrological restoration can enhance wetland hydroperiod, water depth and wetland vegetation, but more resources should be allocated to short- and long-term monitoring of the restoration success., Competing Interests: The authors received funding form The Mosaic Company (www.mosaicco.com/). This does not alter our adherence to PLOS ONE policies on sharing data and materials. There are no patents, products in development, or marketed products to declare.

Soil carbon sequestration in agroecosystems could play a key role in climate change mitigation but will require accurate predictions of soil organic carbon (SOC) stocks over spatial scales relevant to land management. Spatial variation in underlying drivers of SOC, such as plant productivity and soil mineralogy, complicates these predictions. Recent advances in the availability of remotely sensed data make it practical to generate multidecadal time series of vegetation indices with high spatial resolution and coverage. However, the utility of such data largely is unknown, only having been tested with shorter (e.g., 1-2 yr) data summaries. Across a 2,000 ha subtropical grassland, we found that a long time series (28 yr) of a vegetation index (Enhanced Vegetation Index; EVI) derived from the Landsat 5 satellite significantly enhanced prediction of spatially varying SOC pools, while a short summary (2 yr) was an ineffective predictor. EVI was the best predictor for surface SOC (0-5 cm depth) and total measured SOC stocks (0-15 cm). The optimum models for SOC in the upper soil layer combined EVI records with elevation and calcium concentration, while deeper SOC was more strongly associated with calcium availability. We demonstrate how data from the open access Landsat archive can predict SOC stocks, a key ecosystem metric, and illustrate the rich variety of analytical approaches that can be applied to long time series of remotely sensed greenness. Overall, our results showed that SOC pools were closely coupled to EVI in this ecosystem, demonstrating that maintenance of higher average green leaf area is correlated with higher SOC. The strong associations of vegetation greenness and calcium concentration with SOC suggest that the ability to sequester additional SOC likely will rely on strategic management of pasture vegetation and soil fertility., (© 2017 by the Ecological Society of America.)

Pastures are an extensive land cover type; however, patterns in pasture greenhouse gas (GHG) exchange vary widely depending on climate and land management. Understanding this variation is important, as pastures may be a net GHG source or sink depending on these factors. We quantified carbon dioxide (CO 2 ) and methane (CH 4 ) fluxes from subtropical pastures in south Florida for three wet-dry seasonal cycles using eddy covariance, and estimated two annual budgets of CO 2 , CH 4 , and GHG equivalent emissions. We also estimated the impact of water retention practices on pasture GHG emissions and assessed the impact of these emissions on stakeholder payments for water retention services in a carbon market framework. The pastures were net CO 2 sinks sequestering up to 163 ± 54 g CO 2 -C·m -2 ·yr -1 (mean ± 95% CI), but were also strong CH 4 sources emitting up to 23.5 ± 2.1 g CH 4 -C·m -2 ·yr -1 . Accounting for the increased global warming potential of CH 4 , the pastures were strong net GHG sources emitting up to 584 ± 78 g CO 2 -C eq.·m -2 ·yr -1 , and all CO 2 uptake was offset by wet season CH 4 emissions from the flooded landscape. Our analysis suggests that CH 4 emissions due to increased flooding from water management practices is a small component of the pasture GHG budget, and water retention likely contributes 2-11% of net pasture GHG emissions. These emissions could reduce water retention payments by up to ~12% if stakeholders were required to pay for current GHG emissions in a carbon market. It would require at least 93.7 kg CH 4 -C emissions per acre-foot water storage (1 acre-foot = 1233.48 m 3 ) for carbon market costs to exceed water retention payments, and this scenario is highly unlikely as we estimate current practices are responsible for 11.3 ± 7.2 kg CH 4 -C emissions per acre-foot of water storage. Our results demonstrate that water retention practices aimed at reducing nutrient loading to the Everglades are likely only responsible for a minor increase in pasture GHG emissions and would have a small economic consequence in a carbon market., (© 2017 by the Ecological Society of America.)