A simulation model of cereal-legume intercropping systems for semi-arid regions I. Model development

摘要: Cereal-legume intercropping plays an important role in subsistence food production developing countries, especially situations of limited water resources. Crop simulation can be used to assess risk for intercrop productivity over time and space. In this study, a simple model was developed cereal legume growth yield, under semi-arid conditions. The is based on radiation interception use, incorporates stress factor. Total dry matter yield are functions photosynthetically active (PAR), the fraction intercepted use efficiency (RUE). One two PAR sub-models estimate from solar radiation; either 50% or ratio (PAR/SR) function clearness index (K-T). calculated Beer's Law with crop extinction coefficients (K) field experiments previous reports. RUE as available soil depth 900 mm (ASW). Either balance method decay curve approach determine ASW. Thus, alternatives each three factors, i.e., PAR/SR, K ASW, were considered, giving eight possible models (2 methods x 3 factors). calibration validation carried out maize-bean systems using data collected region (Bloemfontein, Free State, South Africa) during seven growing seasons (1996/1997-2002/2003). combination estimated index, coefficient experiment gave most reasonable acceptable result. study simple, so modelling employed develop other cereal-legume regions. (c) 2004 Elsevier B.V. All rights reserved.