SIMULATION OF OIL YIELD PROVIDES GUIDELINES FOR DESIGN, MANAGEMENT, AND RESEARCH OF HEDGEROW OLIVE ORCHARDS
This paper describes the origins and use of a simulation model of oil yield of olive hedgerow orchards that combines calculations of hedgerow illumination in response to orchard structure, canopy depth, canopy width, canopy slope and row spacing, with measured responses of oil yield to incident solar radiation. Simulation results for N-S oriented orchards reveal that orchard yield of hedgerows of rectangular shape reaches a maximum when canopy depth equals alley width (row spacing - canopy width) and decreases at wider spacing, and/or with wider canopies, as the length of productive row decreases per unit orchard area. Yields of wide canopies can be substantially increased (to 40%) by applying slopes to canopy walls, in part because sloping canopies allow closer row spacing and hence more row length per unit orchard area. By comparison, responses to latitude in the range 40-30° due to greater radiation during fruit filling are small, to +20%, and do not warrant adjustment to row spacing. Simulations suggest that high yields can be obtained within the wide range of high density (HD) to super-high density (SHD) orchards provided attention is paid to structure. For example, applying a 10° slope to 4-m deep, 3-m wide HD canopy increases yield from 2060 to 2580 kg ha-1, by a combination of greater illumination and extra row length achieved by narrowing row spacing from 7 to 6 m. Yield then is comparable to a 1-m wide, 2-m deep SHD canopy with row spacing of 3 m. The paper identifies a role for modelling in guiding research, development, and maintenance of optimal structures in hedgerow olive orchards. It also identifies the need for observations and experiments in a range of hedgerows types together with complete descriptions of structural parameters.
Connor, D.J. and Gómez-del-Campo, M. (2014). SIMULATION OF OIL YIELD PROVIDES GUIDELINES FOR DESIGN, MANAGEMENT, AND RESEARCH OF HEDGEROW OLIVE ORCHARDS. Acta Hortic. 1057, 209-219
hedgerows, olive, structure, yield, simulation models