Remote sensing fordetection and monitoring of the cropland waterlogging in arid and semi-arid regions

This study demonstrates utility of integration of remote sensing and GIS techniques for assessment of surface waterlogged areas and cultivated lands in arid and semi-arid regions. The Landsat images from 1985 to 2015 were used for quantifying the quinquennial changes in the cultivated land and surface waterlogging in the Nubaria area in Egypt. The procedure derives the Normalized Difference Water Index (NDWI) and the Normalized Difference Vegetation Index (NDVI) from the Landsat images to detect the cultivated lands and surface waterlogging areas, and then incorporates vector-based data layers within a GIS to quantify the spatial and temporal changes in the agricultural lands and waterlogged areas in the last three decades. The results indicated that the waterlogging in the study area induced by seepage from water canals, lack of maintenance or absence of drainage system, and topography as water flows in the saturated soil and concentrate in the lowlands to form water ponds. The impact of waterlogging in the El Marbat depression is significant and leads toloss of agricultural land. We concluded that remote sensing coupled with Geographical Information Systems (GIS) offers an excellent alternative to conventional mapping techniques in monitoring and mapping of cultivated land and surface waterlogged areas.