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LTAR Phosphorus Budget Summary

    Surface agronomic P budgets for 61 cropping systems using field-scale P flux data across 24 research sites in the United States and Canada. Data are representative of P inputs and outputs associated with the production of each crop in a respective rotation year, ranging from 1 to 10 rotation years. This dataset provides a comparison of field-scale soil surface P fluxes and phosphorus budgets across sites and cropping systems.

    Manuresheds: Redesigning crop-livestock agriculture for sustainable intensification

      The Long-Term Agroecosystem Research (LTAR) network is exploring the concept of the “manureshed,” the manure-spreadable land in the geographic, environmental, and social radius of a confined livestock operation. To better understand opportunities for expanding manuresheds in the United States, we identified the nationwide, county-level pattern of livestock distribution, manure excess, and crop assimilation of manure nutrients.

      Data from: Six years of ecosystem-atmosphere greenhouse gas fluxes measured in a sub-boreal forest

        Continuous tower-based measurements of the ecosystem-atmosphere exchange of CO2 and CH4 are presented, recorded over the period 2012–2018 and reported at a 30-minute time step at a sub-boreal forest in the northeastern United States. Additionally, we describe a five-year (2012–2016) dataset of chamber-based measurements of soil fluxes of CO2, CH4, and N2O (2013–2016 only), conducted each year from May to November. These data can be used for process studies, for biogeochemical and land surface model validation and benchmarking, and for regional-to-global upscaling and budgeting analyses.

        OPUS

          A hydrologic simulation model for studying the effects of management practices on movement of sediment and chemicals in response to rainfall or irrigation on small field areas. Includes models for plant growth and nutrient cycling, and operates on a continuous basis. Weather conditions and rainfall may be stochastically simulated.

          NUOnet (Nutrient Use and Outcome Network) database

            The Nutrient Uptake and Outcomes (NUOnet) database will be able to help establish baselines on nutrient use efficiencies; processes contributing to nutrient losses; and processes contributing to optimal crop yield, nutritional and organoleptic quality. This national database could be used to calculate many different environmental indicators from a comprehensive understanding of nutrient stocks and flows.

            Data from: Switchgrass cultivar, yield, and nutrient removal responses to harvest timing

              Objectives for this study were to compare switchgrass yields from 2010–2011 on eight widely used and experimental upland and lowland genotype (whole plot) at two locations in Tennessee, to determine: (i) which harvest timing (split-plot) provides maximum yield; (ii) effects of harvest timing (mid-Sep, Oct, Nov, and late Oct) on overall total P and K removal; and, (iii) how results are affected by cultivar.

              Microbial community structure is affected by cropping sequences and poultry litter under long-term no-tillage

                Soil microorganisms play essential roles in soil organic matter dynamics and nutrient cycling in agroecosystems and have been used as soil quality indicators. The response of soil microbial communities to land management is complex and the long-term impacts of cropping systems on soil microbes is largely unknown. Therefore, changes in soil bacterial community composition were assessed in response to cropping sequences and bio-covers at long-term no-tillage sites.