Crop Water Productivity as Influenced by Irrigation Improvement in the Nile Delta

摘要

The overall goal of the irrigation improvement project (IIP) is to improve the social and economic conditions of Egyptian farmers through development and use of improved irrigation water management and associated practices, which will increase crop production and, as a result, the farmers' income mainly by improving the irrigation infrastructure, facilitating a more equitable distribution of water and improving on-farm water management. This study is aimed at evaluating and monitoring the impacts ofthe IIP on crop water requirements, crop yields, and crop water productivity under changing irrigation and cultural practices in the north Nile Delta. Two branch Canals (improved and unimproved) were selected on the Meet Yazid command area, Kafr El-Sheikh, Egypt, sample tertiary units were selected, six in each branch Canal, and distributed at head, middle and tail locations and were selected purposively to reflect different conditions. Six fields on each Mesqa were selected and distributed at head, middle and tail locations on the Mesqa. Two main summer crops (rice and cotton) and two main winter crops (Egyptian clover {Berseem} and wheat) were studied on each Mesqa. The effect of the IIP on six indicators of the physical and economical water productivity for selected crops were investigated and compared with the unimproved area. The results revealed that average crop evapotranspiration ranged from 702-744 mm for rice, 476-517 mm for cotton, 293-316 mm for wheat, and 388-420 mm for Egyptian clover inboth improved and unimproved areas, respectively. It can be concluded that the irrigation improvement increased yield by 9, 23, 6, and 45% and saved water by 20, 5, 44, and 7% for rice, cotton, wheat, and Egyptian clover compared to the unimproved area.Average values of crop water productivity were 1.01, 0.72, 1.54, and 10.46 kg m~(-3) in the improved area compared to 0.93, 0.47, 1.44, and 7.04 kg m~(-3) in the unimproved area at average crop evapotranspiration of 723, 497, 305, and 404 mm for rice, cotton, wheat, and Egyptian clover, respectively. It is also noted that applying deficit irrigation for cotton by 4% during the vegetative stage increased crop water productivity by 39% in the improved area. Optimum design and implementation of the irrigation improvement project are recommended for water saving and best management practices of irrigation and water resources in the north Nile Delta, Egypt.