Modelling adaptive management of intercropping in vineyards to satisfy agronomic and environmental performances under Mediterranean climate

In the Mediterranean area, rainfed viticulture is exposed to irregular rainfall distribution. The impacts on production and environment can be mitigated by appropriate management practices like, for instance, the introduction of cover crop in the inter-rows in vineyards. This paper presents the VERDI simulation model created to study various adaptive intercrop management strategies at field scale. The purpose is to design management strategies that are responsive to the water status of the biophysical system (soil - grapevine - intercrop) and the past and current climatic conditions. VERDI realistically reproduces the dynamic interactions between the biophysical system and the decision system in varying Mediterranean rain regime. The decision system works as an interpreter of a management strategy, defined as a set of soil surface management activities (e.g. mechanical weeding of the intercrop) that are linked by temporal constraints (e.g. sequencing, synchronisation) and organisational or programmatic specifications (e.g. iteration). The adaptive capabilities of the strategies are distinguished according to the different sources of flexibility to be exploited at operational, tactical, and strategic levels. A simulation study is reported that involves more or less flexible strategies under different climate scenarios. The simulation results proved that, in case of severe drought, the most flexible strategy yields the best trade-off between agricultural production and environmental services over the years. (C) 2011 Elsevier Ltd. All rights reserved.