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Subtropical humid grazing lands represent a large global land use and are important for livestock production, as well as supplying multiple ecosystem services. Patch-burn grazing (PBG) management is applied in temperate grazing lands to enhance environmental and economic sustainability; however, this management system has not been widely tested in subtropical humid grazing lands. The objective of this study was to determine how PBG affected forage resources, in comparison with the business-as-usual full-burn (FB) management in both intensively managed pastures (IMP) and seminative (SN) pastures in subtropical humid grazinglands. We hypothesized that PBG management would create patch contrasts in forage quantity and nutritive value in both IMP and SN pastures, with a greater effect in SN pastures. A randomized block design experiment was established in 2017 with 16 pastures (16 ha each), 8 each in IMP and SN at Archbold Biological Station's Buck Island Ranch in Florida.

Wetlands are an important source of CH4globally. However, uncertainty surrounding the impact of anthropogenic activities on CH4emissions from wetlands limits understanding of how these ecosystems will respond to management changes. Furthermore, by neglecting the potential for management to influence CH4emissions likely inflates error of CH4emissions for regional and global CH4models. This study employed a replicated factorial experimental design to investigate how management of the agricultural landscape, including grazing and/or management intensity, influences net CH4emissions from embedded, seasonal subtropical wetlands. This research further determined key mechanisms by which management decisions at the landscape scale modulate CH4emissions from the embedded wetlands. Net CH4exchange was measured using a closed chamber system over two complete wet/dry seasonal cycles in 16 wetlands embedded in either agronomically improved pastures (improved wetlands) or less intensively grazed unfertilized seminative pastures (seminative wetlands), as well as in grazed and ungrazed wetlands in each treatment. Emissions of CH4were higher from improved wetlands (2.82 μmol m−2s−1) than seminative wetlands (0.75 μmol m−2s−1), particularly during the wet season. Enhanced CH4emissions in improved wetlands relative to seminative wetlands were caused by increased soil wetness and by higher biomass in improved seminative wetlands. Unlike subtropical flooded pastures, our results showed that grazers do not alter CH4emissions from subtropical wetlands. Current and future changes in management intensity of pastures may cause shifts in net soil CH4emissions from embedded subtropical wetlands, which could further enhance this emission source. Wetlands are methane sources, but little is known regarding how surrounding agricultural practices impact emissionsWetlands embedded in intensely managed pastures have higher methane emissions than wetlands surrounded by seminative landscapesWhether a wetland was grazed or ungrazed had no impact on the amount of methane released from the wetland

•We consider the trade-offs among “good” ecosystem services and “bad” ecosystem disservices attributable to past and current ranchland management and how such trade-offs depend on analysis at the scale of the ranch, the region, or the Earth.•We focus on trade-offs in ecosystem services at one working ranch—Buck Island Ranch, location of the MacArthur Agro-ecology Research Center, lying in the headwaters of Florida’s Everglades—and managed for 25 years as a full-scale cow–calf operation by Archbold Biological Station, one of the world’s preeminent ecological research centers.•The synthesis of how this ranch functions as an ecosystem (species, habitats, nutrient dynamics, hydrology, etc.) is set in the context of financial realities and economic viability.•We develop a conceptual model to visualize trade-offs among ecosystem services and disservices, and provide insight into what it takes to be sustainable ecologically and economically.

•The Northern Everglades Payment for Environmental Services (NE-PES) Program implemented by the South Florida Water Management District (SFWMD) is a unique example of an operating market-like payment for environmental services program on working ranchlands.•The SFWMD enters into 10-year contracts to pay ranchers who dedicate parts of their ranch to providing water retention or nutrient removal services.•NE-PES monitoring procedures were designed to assure that water was managed as agreed to in the contracts and annual payments only were made if contract terms were honored.•Key challenges to the design of monitoring procedures were that the protocol must 1) satisfy the buyer that they were getting the services they paid for, 2) assure the sellers that the services they provide are being fairly assessed, and 3) be feasible to administer over a large number of ranches in an expansive working agricultural landscape.

•The Long-Term Agroecosystem Research Network launched the LTAR Agricultural Performance Indicator Framework to evaluate how agricultural innovations perform relative to sustainable intensification goals in five domains: Environment, Productivity, Economic, Human Condition, and Social.•Here we describe our progress and plans for measuring the performance of agricultural innovations on rangelands.•We present a method for measuring outcomes of management innovations against site-specific benchmarks, which can be applied in grazinglands worldwide.•LTAR typically studies management on fine scales (ecological site, ranch); how to measure effects on broad scales (landscape, community) remains a persistent question.•LTAR’s Agricultural Performance Indicator Framework will evolve with stakeholder engagement.

Rangelands account for a large portion of global carbon stocks and have high potential for carbon sequestration if managed properly. Grazing has variable effects on soil organic carbon depending on climate, geography, and soil type; therefore, grazers in various regions may need to be managed differently to ensure optimum carbon sequestration. This study aimed to assess the impacts of cattle grazing on soil carbon in seminatural subtropical humid rangelands in Florida. We measured root biomass, bulk density, soil organic carbon (SOC), and total carbon (TC) concentrations and used the equivalent soil mass method to assess organic carbon stock (OCS) and total carbon stock at three depths (0−5 cm, 5−15 cm, and 15−30 cm) inside and outside of five 15-yr-old grazing exclosures. We also surveyed the vegetation at each sampling location and litter biomass inside and outside of exclosures. We found that grazing increased bulk density, decreased root biomass, but did not affect litter amount. SOC and TC concentrations did not differ significantly between ungrazed and grazed plots. On an equivalent soil mass basis, we found greater soil carbon stocks in grazed plots within the shallower part of the soil (0−5 cm). Removal of grazing resulted in a clear difference in vegetation composition between grazed and ungrazed plots, with grazed plots having higher grass cover (on average 60% in grazed vs. 13% in ungrazed) and ungrazed having higher forb cover (on average 78% in ungrazed vs. 32% in grazed). Results provide evidence that grazing increased soil carbon stocks in the top layer of soil, but longer-term studies are needed to assess the impact of grazing on SOC concentrations. To further clarify the impact of grazing on drivers of soil carbon in subtropical humid seminatural grasslands, we recommend further study of grazing impacts on productivity, root production and turnover, and microbial responses.

Subtropical and tropical wetlands play a prominent role in the global carbon (C) cycle; yet factors that influence their C fluxes remain uncertain. We collected measurements from a temporarily flooded subtropical wetland over 3 years to investigate environmental drivers impacting CO2and CH4fluxes. The wetland was a sink of CO2(−469 to −380 g C‐CO2· m−2· year−1) and a source of CH4(25.1 to 32.1 g C‐CH4· m−2· year−1) to the atmosphere. Dry season CH4emissions represented 41 to 49% of the annual budget, reflecting the importance of continuous CH4flux measurements. Gross primary productivity (GPP) increased with temperature and radiation, and the influence of VPD on GPP varied with soil inundation. Higher water tables decreased Recoand increased GPP, and a higher GPP in turn lead to enhanced Recolikely through enhancements of GPP on autotrophic respiration. This suggests that the impact of the water table on Recodepends on the cancelling effects of hydrology and GPP. Emissions of CH4increased with soil temperature, water table, and GPP until soils were inundated at which point temperature and GPP became the main drivers. Water table and temperature influenced GPP and CH4fluxes, and increases in GPP directly enhanced CH4emissions. In addition to impacting C fluxes directly through water table depth, hydrology also determined the hierarchy of the dominance of factors controlling C fluxes and their response. The positive climate forcing of subtropical wetlands may be dictated by plant‐mediated and climate interactions, with hydrological factors playing a major role in determining the greenhouse gas sink or source strength of subtropical wetlands. Soil drives subtropical wetland C fluxes through variations in water table depth and determines dominant factors controlling fluxesGPP drives CH4 fluxes as demonstrated using tools that disentangle the direct and indirect effects of key factors on C fluxesA large contribution of non‐growing season CH4 fluxes to annual budgets show these periods cannot be ignored