EFFECT OF IRRIGATION IMPROVEMENT ON CROP PATTERN AND CROP WATER REQUIREMENTS USING REMOTE SENSING AND GIS TECHNIQUES

The cropping pattern and crop evapotranspiration (ETc) of a region are mainly affected by the efficiency of the irrigation system. The objectives of this study were to investigate the impact of irrigation projects in North Delta on crop pattern and water consumption. Remote sensing (RS) and GIS techniques were used to evaluate crop pattern and ETc on El Moheet Canal, North Delta. This canal was subject to irrigation improvement practices (Mesqas and Marwas). This study was carried out during two summer growing seasons (2011, before the improvement and 2013, after the improvement). The obtained results showed that the pixels of the selected canal in both summer growing seasons were classified into 7 land uses (rice, cotton, seed melon, maize, open water, roads, and urban). Before the improvement, cotton was the dominant crop (42.7 %) followed by rice (33.3 %), seed melon (14.5%), and maize (9.5%). However, after the improvement, rice was the dominant crop (74.1%), followed by seed melon (10.7 %), cotton (9.2 %), and maize (6.0 %). The percentage of rice was strongly increased by about 113 % after the improvement. On the other hand, cotton, maize and seed melon were significantly decreased by about 79, 40 and 29 %, respectively, when compared with their areas before the improvement. It could be concluded from the Landsat data that the overall ETc was decreased after irrigation improvement in 2013 by about 4.3 %, whereas water requirement/ha was decreased by about 6.3 %. The obtained images also showed that the cultivated area was decreased from 2011 to 2013 by about 4.3 % due to urbanization. However, the non-cultivated area was increased by about 25 %. Crop distribution and the equity in water distribution along the branch canal were improved due to irrigation improvement. In conclusion, the improvement of the irrigation system saved irrigation water and raised the distribution equity of water