Year Established: 2012 Start Date: 2012-03-01 End Date: 2013-02-28
Total Federal Funds: $22,008 Total Non-Federal Funds: $8,599
Principal Investigators: Samuel Sandoval Solis
Abstract: Analyzing who is using the water, where, but most importantly, how efficiently, it is of substantial importance in order to identify potential places where improvements can be made. Water use efficiency is defined as the ratio of the evapotranspiration of the crop grown and the applied water to that particular crop. The evapotranspiration of applied water is the amount of applied water beneficially transpired by plants, retained in the plant tissue and evaporated from adjacent soil surfaces during a specific period of time; it depends on the type of crop, i.e. corn, alfalfa, tomato, etc. The applied water is the quantity of water applied to a specific crop per unit area, it depends on the irrigation method used, i.e. sub-surface, surface, sprinkler and drip. Understanding the trends of how the water use efficiency has changed in time and varied in space is relevant because it helps to quantify how much water has been used, for which crops and where. Five irrigation surveys have been conducted in California: 1972 (Stewart 1975), 1980(Hagan and Wagner 1983), 1991(Snyder et al. 2006), 2001(Orang et al 2008) and 2010(DWR 2011). These surveys have improved the understanding and trends of the irrigations methods used and the types of crops grown in California. However, the format of the survey data can be improved, at this moment data is stored in tables, which makes it difficult to use and visualize. This information could be presented spatially using geographic information systems (GIS) that will make easier its display, manage and storage. In addition, there is no analysis of how much the water use efficiency varies in space and time, for instance, the efficiency of sprinklers may vary from one place to another due to local conditions such as wind, temperature or because of the type of the sprinkler. This uncertainty can be addressed by analyzing the range of efficiencys values that each irrigation method can have. Addressing the uncertainty can help to understand and inform, which methods have a more variable efficiency and in which places the efficiencies differs of their typical value.