Center of Excellence for Geospatial Information Science (CEGIS)
Current CEGIS ProjectsAcademic Affiliates
Soil Moisture Measurement from Remotely Sensed Images
Additional information and project materials
Objective: Field collected values of soil moisture from Theta probes are being used to calibrate transformations of Landsat Thematic mapper (TM), Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), Advanced Land Imager (ALI), Hyperion and airborne-collected hyperspectral images to create soil moisture values directly from the image radiances.
History: Originally funded by Land Remote Sensing (LRS) as a 3-year project.
Accomplishments: We continue to have a robust collaboration with many distinguished scientists at the U.S. Department of Agriculture (USDA), the Institute for Technology Development (ITD), the University of Georgia, and the University of Missouri - Rolla. We employed a Ph.D. student from the University of Georgia's National Environmentally Sound Production Agriculture Laboratory (NESPAL); this employee completed extensive field work associated with the goals of the project. In addition to satellite remote sensors, we have deployed a leading-edge airborne hyperspectal sensor and collected some unique datasets. Preliminary analyses show good correlations of measured soil moisture with a few specific bands in the infrared.
Results and Outputs: The reported results of our technical approaches from various preliminary stages has resulted in a poster presented at the USGS Land Remote Sensing Science Fair, Reston, VA. In addition, we are preparing a paper for submission as a U. S. Geological Survey Open-File Report and a paper for submission to the journal Geosciences and Remote Sensing.
Current Status (2007): We have an extensive database of images from ASTER, TM, ALI, Hyperion, and airborne hyperspectral (collected under contract in fiscal year 2005 and fiscal year 2006) data over the test site in the Little River, Georgia, watershed. These images have been preprocessed including rectification to ground control, conversion of pixel values to reflectance and radiance, and generation of tasseled-cap transformations. Acquisition of an additional airborne hyperspectral image is now under contract.
Planned Future Work: In collaboration with our partners, the soil moisture values for the point samples from the theta probes are being scaled to pixel size (30 x 30 m) areas with in-field measurements of climate conditions, vegetation, soil and air moisture, and spectral reflectances, during airborne hyperspectral flights. These pixel area measurements will be compared to image reflectances and interpolated to a regional assessment of soil moisture. Through image transformations (including tasseled-cap and modified wetness calculations) and statistical analyses, such as canonical analysis and correlation, we hope to establish a capability to predict soil moisture values from image radiances. In association with USDA, ITD, NESPAL, and UGA, we will complete this project in fiscal year 2007.