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Product Design and Methodology
° field capacity ° wilting point • Soil fertility can be defined as additional stress on crop growth influenced by: ° water productivity parameter ° the canopy growth development ° maximum canopy cover ° rate of decline in green canopy during senescence AquaCrop separates soil evaporation (E) from crop transpiration (Tr). The simulation of Tr is based on: • Reference evapotranspiration • Soil moisture content • Rooting depth Simulation of soil evaporation depends on: • • • • • •
Reference evapotranspiration Soil moisture content Mulching Canopy cover Partial wetting by localized irrigation Shading of the ground by the canopy
Field Management Characteristics of general field management can be specified, reflecting two groups of field management aspects: soil fertility levels, and practices that affect the soil water balance. In terms of fertility levels, the user can select from predefined levels (non-limiting, near optimal, moderate, and poor) or can specify parameters obtained from calibration. Field management options influencing the soil water balance that can be specified in AquaCrop are mulching, runoff reduction, and soil bunds. Irrigation Management One of the strengths of AquaCrop is simulation of irrigation management, which offers the following options: • • • • • • • •
Rainfed-agriculture (no irrigation) Sprinkler irrigation Drip irrigation Surface irrigation by basin Surface irrigation by border Surface irrigation by furrow Scheduling of irrigation can be simulated as fixed timing or depletion of soil water Irrigation application amount can be defined as fixed depth or back–field capacity. Looking Beyond the Horizon • http://dx.doi.org/10.1596/978-0-8213-9768-8