Water table level in relation to EO-1 ALI and ETM+ data over a mountainous meadow in California

Abstract

In an effort to map water table levels in an irrigated high mountain meadow, we explored the potential of the spectral reflectance of meadow surface covers. Multispectral data acquired from the earth observing-1 (EO-1) advanced land imager (ALI) and Landsat enhanced thematic mapper plus (ETM+) with similar band specifications and the same spatial resolution of 30 m were tested. Preliminary regression analysis reveals that the blue, red, and near-infrared bands all correlate strongly with water table levels. The visible bands have negative correlations and the near-infrared band has a positive correlation. During the early half of the growing season, weekly water table levels averaged on a monthly basis show strong correlations with spectral data of the meadow. The normalized difference vegetation index (NDVI) has a better correlation with water table level than several other linear transformation features obtained with principal component analysis and the Kauth–Thomas transform.