|Author:||Croon, F. W. ; Risseeuw, I. A.|
|Book Group Author:||NA|
The authors argue that in many arid, semi-arid and sub-humid regions policies to minimize irrigation water supplies and recycle drainage water in already water-short regions, may not always result in sustainable benefits for the agricultural, fishery and ecological sectors. In the lower parts of irrigation command areas and drainage catchments, where shortages of irrigation water can already be serious, mixed flows of tail and sub-surface water draining from better watered areas are vital to their irrigated crops. Increasing the water application efficiency causes a significant decrease in leaching and in irrigation surface runoff. This may cause increased soil salinity levels and decreased crop yields, which will be difficult to redress. In addition, savings at field level may be insignificant at basin level. Furthermore, wetland production and biodiversity will suffer, unless decreased drainage water availability and quality is compensated by "saved" fresh irrigation water allocations.
|Journal:||Transactions of the 19th International Congress on Irrigationand Drainage, Beijing, China, 2005. Vol 1B: Water quality, salinitymanagement|
application, biodiversity, control, crop yield, drainagewater, irrigation water, semiarid zones, soil salinity, waterconservation, water quality, water use efficiency, wetlands, watercomposition and quality, Erosion; Soil and Water Conservation (PP400),Soil Water Management (Irrigation and Drainage) (JJ800) (Revised June2002) [formerly Soil Water Management], Water Resources (PP200), SoilFertility (JJ600)