Analysis of Multi-Indices from Hyperspectral strip along Climatic Gradient as Surrogates of Climate Change

Assessment of spectral vegetation indices’ change along a climatic gradient as surrogates of climate change effect on desert fringe ecosystems is conducted in the southeastern Mediterranean utilizing Hyperspectral strip acquired by SPECIM FENIX sensor. This study presents the strip’ center-line profile of 6 spectral indices (out of 27 indices): Normalized Difference Vegetation Index (NDVI), Crude Protein (CP), Visible Atmospherically Resistant Index (VARI), Red Edge Ratio Normalized Difference Vegetation Index (RERNDVI), Neutral detergent fiber (NDF), and Landsat TM2 and TM4 ratio. These profiles were smoothed using Savitzki-Gulay filter and their general trend along the profile was determined by using linear regression technique. R
²
, the coefficient of determination, represents implicitly the sensitivity of each of the spectral indices for changes in vegetation and soil properties to spatial variation in rainfall and Potential Evapotranspiration (PET). Three indices showed significant north to south trend despite effects of human disturbance on the natural ecosystems: NDVI $\left(0.45 R^{2}\right)$; Red-Edge index $\left(0.528 \mathrm{R}^{2}\right)$ and VARI $\left(0.689 \mathrm{R}^{2}\right)$. These indices may serve mapping and monitoring desert fringe ecosystems response to global warming.