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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

596 datasets

Long-Term Agricultural Research (LTAR) network - Meteorological Station - Hawbecker - Upper Chesapeake Bay

    The USDA-ARS Pasture Systems and Watershed Management Research Unit established a meteorological station in 2015 as part of the Upper Chesapeake Bay (UCB) site in the Long-Term Agroecosystem Research (LTAR) network (est. 2012). Measurements include air temperature and humidity, shortwave (solar) irradiance, longwave (thermal) radiation, wind speed and direction, barometric pressure, and rainfall. Data are recorded at 15-minute intervals.

    Long-Term Agricultural Research (LTAR) network - Meteorological Station - Rock Springs - Upper Chesapeake Bay

      The USDA-ARS Pasture Systems and Watershed Management Research Unit established a meteorological station in 2015 as part of the Upper Chesapeake Bay (UCB) site in the Long-Term Agroecosystem Research (LTAR) network (est. 2012). Measurements include air temperature and humidity, shortwave (solar) irradiance, longwave (thermal) radiation, wind speed and direction, barometric pressure, and rainfall. Data are recorded at 15-minute intervals.

      Irrigation Residue Removal Study for Greenhouse gas Reduction through Agricultural Carbon Enhancement network and Resilient Economic Agricultural Practices in Lincoln, Nebraska

        USDA-ARS REAP Study (Ithaca, NE) - NEMEIRR Sustainable intensification of high-yielding production systems may help meet increasing demands for food, fuel, and fiber worldwide. Specifically, corn stover is being removed by producers for livestock purposes, and stover is also targeted as a primary 2nd generation biofuel feedstock. The NEMEIRR experimental objectives are to quantify how stover removal (no removal, moderate removal, high removal) and tillage management (no-till, disk) affect crop yields, soil organic carbon, soil greenhouse gas emissions, and other soil responses (microbial community structure, function; soil health). This experiment is conducted in a fully irrigated continuous corn system in the western Corn Belt, and soil and plant measurements have been taken since study establishment in 2001.

        EcoTrends datasets, Jornada Basin data portal

        NAL Geospatial Catalog
          This dataset links to the Jornada data homepage, which links to 153 individual datasets. Those datasets can then be searched based on Title, Keyword, or Investigator. The EcoTrends project is a collaborative effort among state and federal agencies and institutions, at present primarily in the US, to make long-term ecological data easy to access, analyze, and compare within and across sites. This website is a portal to a large and diverse collection of standardized long-term ecological datasets and their metadata (> 1200 datasets), unique data exploration, download, graphing and synthesis tools, and information about participating research sites and their parent agencies

          ASRU Study for Greenhouse gas Reduction through Agricultural Carbon Enhancement network in Sidney, Montana

            Information is needed to mitigate dryland soil greenhouse gas (GHG) emissions by using novel management practices. We evaluated the effects of cropping sequence and N fertilization on dryland soil temperature and water content at the 0- to 15-cm depth and surface CO2, N2O, and CH4 fl uxes in a Williams loam (fi ne-loamy, mixed, superactive, frigid, Typic Argiustolls) in eastern Montana.