The relationship between the development of the morphometric characteristics and the variances of the vegetation cover’s density during the last fifty years at the downstream of Wadi Allaqi Biosphere Reserve, Aswan, Egypt

This study was conducted to detect the development of the morphometric characteristics downstream of Wadi Allaqi Biosphere Reserve (WABR) via the successive flood years and the impacts on the subsequent changes in the dominating vegetation cover’s density. The downstream part of Wadi Allaqi is commonly termed Khor, which refers to the lateral extensions branched from the water body of Aswan High Dam Lake or what is commonly named Lake Nasser. Khor Allaqi is regarded as the biggest khor amongst the forty-two khors of Aswan High Dam Lake (AHDL) which was created after the construction of Aswan High Dam (1960– 1970). The geomorphologic units which predominate at the study area and its nearby vicinity were identified and classified in the current research. The outcomes of the present study reflected that the flood years (1999, 2008, and 2019) witnessed the highest values of water accretion distances inside Khor Allaqi and were estimated to be 55.4 m, 53.2 m, and 54.4 m, respectively through applying the “History Tool of Google Earth Pro software”. The discrepancies in the woody vegetation cover’s densities via the flood years are combined with the successive changes of the amounts of the rainfall - as a major parameter of climatic changes - basically on the Ethiopian plateau, in addition to the considerable thickness of the flood plain soil overlying the basement rocks distinguishing Wadi Allaqi. The land cover changes of the scattered floristic species of shrubs individuals were calculated by applying the “Calculate Area Tool of Arc GIS 10.2 software” on the supervised LANDSAT ETM⁺ satellite image. It was proved that the woody cover expanded and reached 17.5 km² in the flood year 2019/ 2020.