ESTIMATING PERCENT COVER WITH HIGH RESOLUTION IMAGERY IN THE TEXAS HIGH PLAINS
Soil and Water Management Research
2011 Annual Report
1a.Objectives (from AD-416)
Develop a set of reflectance-based models for estimating percent cover using high resolution satellite data in the Texas High Plains.
1b.Approach (from AD-416)
Ground truth data on percent cover will be collected from 30-40 fields in the USDA-ARS Conservation and Production Research Laboratory, Bushland, Texas, during the 2010 summer cropping season. A GPS will be used to identify the geographic location of the ground truth location. Data collection will be coincided with RapidEye satellite overpasses. A digital camera will be used to acquire photographs of the crops at nadir position. Digital photos will be classified into two categories to calculate percent cover using Multispec image processing system. Finally, spectral reflectance values for the ground truthing location will be extracted from the RapidEye images with a pixel size of 7.5 x 7.5 m to develop and evaluate a set of statistical models for estimating percent cover.
The main objective of this research was to develop a set of reflectance-based models for estimating percent cover using high resolution RapidEye satellite data in the Texas High Plains. An extensive literature review for identifying existing spectral models for estimating percent cover was completed. During the 2010 summer cropping season, we conducted three field surveys to collect data on plant characteristics, including percent cover in 33 fields within our ARS laboratory in Bushland, TX. These surveys were coincided with RapidEye satellite overpasses. A GIS map showing the ground truth locations was developed and overlaid on RapidEye images to extract spectral data for model development and evaluation. Preliminary results on estimating percent cover with RapidEye data was presented at the 2010 annual American Geophysical Union meeting. At present, we are developing a new set of percent cover models that are specific to the Texas High Plains.
The ADODR held several teleconferences, and numerous email and phone calls with the cooperator from RapidEye AG. We also met to discuss the on-going activities while attending the annual meetings of ASA-SSSA-CSSA and American Geophysical Union.