干旱区生态环境知识资源中心

The Jornada Experimental Range (Jornada) in southern New Mexico provides a unique opportunity to use remote sensing techniques to study arid rangeland and the responses of vegetation to changing hydrologic fluxes and atmospheric driving forces. Research by the United States Department of Agriculture Forest Service and Agricultural Research Service at Jornada has been continuous since 1912. The Jornada 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 quantity hydrologic budgets and plant responses to change in components in the water and energy balance at the Jornada. Published by Elsevier Science Inc.