Soil moisture is a key controlling factor for numerous ecological and biophysical processes. While diverse techniques are available to make point estimates of soil moisture, spatially extensive surveys can be logistically difficult and fraught with problems of interpolation. Remote sensing of soil moisture offers the possibility of exhaustive spatial sampling. The efficacy of microwave sensors (both active and passive) in measuring soil moisture is well-studied. However, little research has focused on patterns of radar imagery of natural landscapes. Yet, there is a distinct need to assess the potential of Synthetic Aperture Radar (SAR) for routine environmental monitoring of land surface processes. Environmental monitoring of vegetated landscapes will increase during the next decade as data from spaceborne SAR platforms become more readily available. The project involves the use of SAR data from the European, Canadian, and Japanese orbital platforms to address the variation in canopy and soil moisture and its ecological consequences. These data augment current investigatio ns at two NSF Long Term Ecological Research (LTER) sites, Konza prairie Research Natural Area in the northeast Kansas and Sevilleta National Wildlife Refuge in central New Mexico. Both LTER sites are located within ecological transitional zones (ecotones) in which soil moisture is a major determinant of plant productivity and species composition. The primary products are site-specific time series of soil moisture and canopy change maps. These data will then be used to link remote sensing and groundtruth data with ecological processes.
