Irrigation and soil salinity management are of paramount importance to agriculture sustainability in desert agriculture. Because irrigation water and shallow groundwater that fluxes up through the soil have salts, some level of excess irrigation (beyond crop consumptive use) must be applied to leach salts below the crop root zone. The various irrigation systems utilized, and the management of these systems can have a profound impact on water delivered, leaching achieved, and resulting salt distribution.
Water in the Southwest
The low desert of the Southwestern USA is one of the world’s most productive regions for crop production. However, this productivity is dependent on water from the Colorado River system, which is increasingly unstable and facing prolonged drought. The Colorado River provides water for a broader region that is composed of 5.5 million acres of cropland and is home to about 40 million people. To preserve this system and its water supplies, all water users are currently focused on closing the gap between supply and demand within the Colorado River Basin, where water demands are projected to outstrip supplies by increasing amounts.
Salinity management is another important consideration in the region because irrigation and shallow groundwater contain salts and high evaporation and crop transpiration potentially transport and concentrate these salts in the crop root zone. Thus, water management must address the need for salinity management as well as meet the water requirement of crops. Irrigation management research associated with YCEDA is aimed at developing efficient and sustainable water and salt management technologies.