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Long Term Agroecosystem Research Overview

In pursuit of sustainable U.S. agriculture, the U.S. Department of Agriculture (USDA) launched the Long-Term Agroecosystem (LTAR) network. The LTAR network is composed of 18 locations distributed across the contiguous United States working together to address national and local agricultural priorities and advance the sustainable intensification of U.S. agriculture.

The LTAR network represents a range of major U.S. agroecosystems, including annual row cropping systems, grazinglands, and integrated systems representative of roughly 49 percent of cereal production, 30 percent of forage production, and 32 percent of livestock production in the United States. Furthermore, the LTAR sites span geographic and climatic gradients representing a variety of challenges and opportunities to U.S. agriculture.

The LTAR network uses experimentation and coordinated observations to develop a national roadmap for the sustainable intensification of agricultural production. While the LTAR network is a new network, experimentation and measurements began at some LTAR sites more than 100 years ago, while other locations started their research as recently as 19 years ago.

A primary goal of LTAR is to develop and to share science-based findings with producers and stakeholders. Tools, technologies, and management practices resulting from LTAR network science will be applied to the sustainable intensification of U.S. agriculture. Technical innovations, including new production techniques, genetics, and sensor infrastructure applied at the farm/ranch level can increase the capacity for adaptive management, reduce time and operational costs, and increase profits and the quality of life for producers.

For full list of LTAR sites, view the sites matrix at https://ltar.ars.usda.gov/sites/.

For more information about the LTAR network visit: https://ltar.ars.usda.gov

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Datasets

12 datasets

PhenoCam images from ARSLTARMDCR site, Caroline County, Maryland, USA since 2017

    This data set consists of repeat digital imagery from a tower-mounted digital camera (hereafter, PhenoCam) maintained by the USDA-ARS Hydrology Remote Sensing Laboratory (HRSL) in the Lower Chesapeake Bay (LCB) watershed. HRSL is a member of the PhenoCam network, which has as its mission to serve as a long-term, continental-scale, phenological observatory. Imagery is uploaded to the PhenoCam server every 30 minutes.

    PhenoCam images from ARSOPE3LTAR site, Beltsville Agricultural Research Center, Maryland, USA since 2017

      This data set consists of repeat digital imagery from a tower-mounted digital camera (hereafter, PhenoCam) maintained by the USDA-ARS Hydrology Remote Sensing Laboratory (HRSL) in the Lower Chesapeake Bay (LCB) watershed. HRSL is a member of the PhenoCam network, which has as its mission to serve as a long-term, continental-scale, phenological observatory. Imagery is uploaded to the PhenoCam server every 30 minutes.

      Data from: Interseeded cover crop mixtures influence soil water storage during the corn phase of corn-soybean-wheat no-till cropping systems

        This study was initiated to evaluate, during the following corn (*Zea mays* L.) phase, the effects of interseeded cover crops on soil temperature, soil water balances, evapotranspiration, infiltration, and yield and water use efficiency of corn. The study was conducted at the USDA Beltsville Agricultural Research Center, Beltsville, MD from 2017 through 2020. The cropping systems under study were primarily sequences of corn-soybean (*Glycine max* L.)-wheat (*Triticum aestivum* L.)-double crop soybean all planted with no-tillage management.

        Choptank Experimental Watershed Soil Moisture Network

          A network of soil moisture and soil temperature profiles as well as solar radiation and precipitation gages are distributed throughout the central region of the DelMarVa peninsula to capture variability of these parameters to give a broad understanding of agricultural conditions in this domain. Soil profile data is captured at depths of 5, 10, 20, and 50 cm below the surface and recorded hourly at locations on the edges of agricultural fields, not inside the production fields.

          Clean Air Status and Trends Network (CASTNET) - Beltsville, United States Environmental Protection Agency

          NAL Geospatial Catalog
            CASTNET measures ambient concentrations of sulfur and nitrogen species as well as rural ozone concentrations. The network includes 90 sites located throughout the US and Canada. Each site measures weekly concentrations of acidic pollutants, base cations and Cl- using a 3-stage filter pack with a controlled flow rate. Most CASTNET sites also include a temperature controlled shelter and continuous ozone monitoring system.