assessment of soil degradation and resilience at northeast nile delta, egypt: the impact on soil productivity

In Egypt, the soil degradation is the main constraint to the development of agricultural sector. In the last few decades, the farmers and the government have made a great effort to resist soil degradation. The resistance of soils to degradation processes by human positive actions is known as soil resilience. This study aims to assess the soil degradation and resilience at northeast Nile Delta and evaluate their impact on the soil productivity. To fulfill these objectives, Landsat ETM+ images and digital elevation model were processed using ENVI 4.7 software to identify the main physiographic units in the area. The recognized units comprised; lacustrine, marine, and alluvial deposits. Twelve soil profiles were undertaken to represent the different mapped units, the locations of the soil profiles were selected to be the same sites previously studied by the Research Institute of Soils and Water (RISW) in 1976. Changes in soil properties and productivity index during the last 35 years (1976–2011) were identified. The status of soil degradation was evaluated; the results indicate that the most active soil degradation processes are water logging salinization, and alkalinization. The soil resilience against salinity, alkalinity and water logging was assessed. It was found that the soil productivity index reflects the balance between soil degradation and resilience. The soil degradation processes overcome the soil resilience in most of the study area where the soil productivity index was decreased in 45.82% of the total area.