Armett-arid region mapping of evapo-transpiration technique

Abstract

ARMETT (Arid Region Mapping of Evapo-Transpiration Technique) can differentiate areas of active obligate phreatophyte vegetation from all other cover types with a spatial accuracy of meters in hot-arid environments where water is the main biolimiting factor to growth. The RERD (Red Edge Response Differentiation) filter within the technique is based on identifying the differences in the spectral responses among actively transpiring vegetation, dormant vegetation, and bare soil in the 500-900nm range of color infrared airphotos using color manipulation. When the spatial distribution of active vegetation is combined with an understanding of the rooting depth of the native species, the lateral extent of areas of shallow groundwater can be constructed. Extension of this technique to three dimensions using I Om resolution Digital Elevation Models (DEMs) provides a tool that can aid in unlocking the dynamics of shallow aquifers and groundwater flow regimes within basins in arid and semi-arid climates.