Submitted to: Remote Sensing of Environment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 19, 1999
Publication Date: November 15, 2000
Citation: HAVSTAD, K.M., KUSTAS, W.P., RANGO, A., RITCHIE, J.C., SCHMUGGE, T.J. `JORNADA EXPERIMENTAL RANGE: A UNIQUE ARID LAND LOCATION FOR EXPERIMENTS TOVALIDATE SATELLITE SYSTEMS AND TO UNDERSTAND EFFECTS OF CLIMATE CHANGE. REMOTE SENSING OF ENVIRONMENT. 2000. V. 74(1). P. 13-25. Interpretive Summary: The purpose of this research project is to determine the effectiveness of remote sensing techniques for monitoring water use by desert vegetation. Our objective is to quantify the differences in water losses between grasslands and shrublands. Many rangelands have changed from grasslands to shrublands in recent decades. These changes have been driven by a variety of causes including drought, fire suppression, and overgrazing. Possible changes in global and regional climatic patterns may further contribute to these vegetation shifts. For deserts, vegetation change is often created by a combination of these factors. Water is one of the critical resources inherent to these deserts, and it is important that we understand how these vegetation changes impact water losses and subsequent availability. This project is a large effort involving collaboration among a number of research units of the Agricultural Research Service. The project is being conducted at the Jornada Experimental Range in southern New Mexico, one of the premier rangeland research facilities in the world. This paper describes the different types of data being collected by this project, and some of the preliminary results from the project are presented.
Technical Abstract: The Jornada Experimental Range (Jornada) in southern New Mexico provides a unique opportunity to use remote sensing techniques to study arid rangeland and responses of vegetation to changing hydrologic fluxes and atmospheric driving forces. Research at the Jornada has been continuous since 1912 by the United States Department of Agriculture (USDA) Forest Service and USDA Agricultural Research Service and has been a National Science Foundation Long-Term Ecological Research site since 1981. These long-term investigations have provided ground data on vegetation characteristics, ecosystem dynamics, and vegetation response to changing physical and biological conditions. To complement the programs of ground measurements, a campaign called JORNEX (JORNada EXperiment) began in 1995 to collect remotely sensed data from aircraft and satellite platforms to provide spatial and temporal data on physical and biological states of the Jornada rangeland. A wide range of ground, aircraft and satellite data have been collected on the physical, vegetative, thermal and radiometric properties of three ecosystems (grass, grass/shrub transition and shrub) typical of the Jornada rangeland and of Southwestern U.S. deserts. Spatial surface energy balance estimates were made from a combination of parameters and state variables estimated from aircraft and ground data. Landscape surface roughness was evaluated with the laser altimetry data and used to estimate aerodynamic roughness. Data from different platforms allowed the evaluation of the landscape at different scales. These measurements are being used to quantify hydrologic budgets and plant responses to change in components in the water and energy balance at the Jornada.