ANSWER Application
The Answer Application is a biological-physical model of water and salt balance, plant water use and plant response to stress coupled with economic calculations for profit in order to consider options for irrigating with water of varied salinity. The coupled model is packaged in a user-friendly menu- and web-based platform. Model inputs characterize the physical (soil hydraulic properties, weather), biological (crop relative response functions to water and salt), management (applied water quality and quantity), and economic (yield value, yield determined and static expenses, capital return, water pricing, farm unit size, etc.) parameters. The application returns yield and profit data for different scenarios of interest and allows consideration of environmental repercussions of economic decisions through calculation of leachate carrying excess water and salts out of the root zone. The application is a useful planning and teaching tool to understand issues of water quality, soil-water-crop-atmosphere relationships, and economic complexities of irrigated agricultural systems.