Monitoring Spatiotemporal Environmental Changes in Dakahlia Governorate, Egypt Using Landsat Imagery

Dakahlia Governorate (Egypt) is considered an important area for plant diversity, facing three major problems, namely: high rate of population increase, limited renewable natural resources, limited production of food, forage, and raw materials for industrial purposes. Two multispectral Landsat imageries (TM and OLI 8) on 6th of March 1999 and 19th of March 2019 were calibrated and processed to produce LULC, different spectral indices (land surface temperature (LST), normalized difference vegetation index (NDVI), normalized difference Built-up Index (NDBI), normalized difference moisture index (NDMI), modified normalized difference of water index (MNDWI) and normalized difference salinity index (NDSI)). Furthermore, the surface temperature was obtained by processing the thermal bands of the Landsat image. Applying the indices on the raw digital numbers to produce a comparative study with the resulted values to detect the environmental change over the two last decades. According to the analysis, the results detected a loss in the vegetation areas and the bare land in favor of urban areas and water bodies to fulfill the requirements of the residents and the developers. That was confirmed with the analysis of the NDBI, NDSI, and LST that showed an increase as a result of urban sprawling. On the other hand, the NDVI explained that the uncontrolled urban sprawl caused the loss of agricultural lands. There was a slight expansion in the wild plant habitats, represented mainly by sparse class and partially by moderately dense class. Accordingly, this could be a result of the mutation in the habitats to favor the spreading of the moderate and sparse vegetation class, which MNDWI and NDMI confirmed.