Long Term Agroecosystem Research Overview
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
LTAR Research Sites
Data from the following LTAR sites are presented. They are related to topics such as agricultural sustainability, climate change, ecosystem services, and natural resource conservation at the watershed or landscape scale.
The data consists of chemical analyses of dissolved ions in samples of surface runoff from natural rainfall events collected from experimental hydrology plots in creosotebush scrub and grass- land areas of the New Mexico State University Ranch and
Precipitation at 1 minute intervals for rain gauges 2-5 with R1 excluded due to periods of interruption. Spatially averaged rainfall over the watershed is calculated in this dataset based on relative coverage of each rain gauge determined from a
Canopy Gap and Basal Gap Intercept data are collected annually for this project beginning in 2008. No data were collected in 2011. There are 4 pairs of plots consisting of control and treatment.
Beginning in 1996, annual photos are taken from each of the 4 corners of each of the 15 70-meter x 70-meter NPP sites between August and November depending on other research activity constraints.
Line-Point Intercept data are collected annually for this project beginning in 2008. No data were collected in 2011. There are 4 pairs of plots consisting of control and treatment.
Surface evaporation is measured weekly to twice weekly using an evaporation pan compatible with standard National Weather Service evaporation measurements. Measurements are made twice per week during hot periods because of high evaporation rate.