Simulation At Regional Level Of Irrigated Wheat And Tomato In A Mediterranean Environment
Free (open access)
M. Rinaldi & R. Ubaldo
In Mediterranean countries, where water-limited conditions are frequent, it is important to identify soil and crop management which optimize resources transformation and maximize farmers’ return. In this research a seasonal merged with a spatial analysis was simulated with AEGIS/WIN, a Geographic Information Systems (GIS) interface from the DSSAT crop simulation package. The case-study refers to a 1000 km2 area (Southern Italy), characterized by 481 soil samples collected at a regular grid. Durum wheat and processing tomato have been simulated punctual-based using soil and long-term weather data (45 years). The two crops have been compared in the following management scenarios: rainfed and three automatic irrigation levels based on soil water content thresholds. Averages and standard deviations of commercial yield (grain and fruit), seasonal irrigation amount, number and profitability were evaluated as model output. GIS allowed one to visualise the output variables in the soil polygons. The wheat productivity was increased by irrigation of 19% and no difference occurred among automatic irrigation thresholds. In tomato the irrigation increased the yield by 3 times with respect to rainfed, with no difference among irrigation scenarios. Net return of wheat was higher in rainfed than irrigated scenarios also for the cost of water and the low price of the product. For tomato CAW 50% resulted in the most profitable scenario. The \“soil x climate” interaction (rainfall, temperature and soil water holding capability) influenced the spatial response at regional level, allowing us to identify the area more productive for wheat and tomato. Keywords: simulation model, durum wheat, processing tomato, irrigation scenarios, soil water content, net return.
simulation model, durum wheat, processing tomato, irrigation scenarios, soil water content, net return.