Water management improvements for agriculture by applying efficient crop schedules in the highland forest of Vilcabamba, Peru

Abstract

The current work is aimed to improve the water management for agriculture, by applying efficient crop schedules in Vilcabamba -and similar areas of the Andean highland forest-, which can satisfy most of the water requirements with rainfed irrigation and maximise the crops yield.  For this purpose, two field practices were carried out during the dry (September 2012) and wet season (February 2013) to measure rivers and canals flows with the velocity/area method.  Nineteen soil samples were collected on-site and analysed, presenting prevalent sandy loam and loam textures.  Cropwat programme and data on climate, crops and soil were used to estimate crop water requirements and scheme irrigation requirements, indicating that crop evapotranspiration is low due to humidity and cool temperature.  Crops did not need any water during the rainy season (December to April), although irrigation requirements occur in the dry season, with a maximum flow capacity of 1.72 L/s in May.  The flow capacity can be satisfied, since small ditches convey approximately 2 L/s to 6 L/s on the same season.  Rainfed farming can be practised, but an initial pre-irrigation that needs to be applied for crops should not be water stressed.  However, if soil is not pre-irrigated the production can be affected, with vegetables and potato crop yields reduced by 4.7% and 1.4%, respectively.  To minimise these effects, both crops are suggested to be planted one month later, adapting their growth period to the rainy season.

Keywords: Crop scheduling, crop water requirements, rainfed irrigation, water management for agriculture, Cropwat