Remotely Identification and Differentiation of Ficus Species in Alexandria City Using Spectral Reflectance Measurements

Nashwa H. Mohamed , Nader A. El-Shanhorey and Salah E. Elsayed

This study was carried out in Alexandria city on eighteen Ficus species (Family Moraceae), to examine how far the remote sensing is considered as an applicable technique and as vegetation indices can differentiate between vegetation cover species depending on spectral reflectance characteristics for each tree species leaves. Results showed that absorption and reflectance spectral characteristics of leaves of each tree species were significantly differentiated by spectral signature curve and average of digital number (DN), that gives the highest value for species with large, thick and dark green leaves such as Ficus platyphylla , Ficus lyrata  and Ficus altissima, comparing to  species with small, white green colored leaves like Ficus microcarpa Hawai, which showed the lowest value. The same trend was shown by, Normalized difference Vegetation index (NDVI) and rationally, the chlorophyll content. On the other hand results of Simple ratio (SR) index were not significantly differed among studied species. It is noticeable of that reflectance of (near-infrared (NIR) region) by leaves varied to its color, size, thickness and internal structure, so this electro-magnetic radiation (EMR) region can be used successfully for species classification. There were a highly correlation between chlorophyll content and NDVI and SR, while results showed no significant correlation between chlorophyll content and DN.  

Key words: Ficus, remote sensing, vegetation indices, NDVI, SR index, spectral curve, chlorophyll.