The modelled productivity of Miscanthus x giganteus (GREEF et DEU) in Ireland

The contribution of Miscanthus biomass to an energy or fibre industry in Ireland can only be estimated if the potential productivity is predicted on a regional basis. In order to parameterise a model to predict dry matter production, growth and climatic measurements were carried out in 1994 and 1995 on a Miscanthus field trial, planted in 1990 in southern central Ireland. These were used to derive relationships between: (i) leaf canopy light interception and thermal time calculated from air temperatures; and (ii) radiation intercepted and above ground biomass. These relationships were used to parameterise an empirical productivity model in which water and nutrient supplies are assumed non-limiting. The output from this model was incorporated into a geographical information system (GIS) to map the predicted potential production of M. x giganteus throughout Ireland, using 10 year daily air temperatures and incident radiation from 23 climatic stations. Across the island, potential biomass yields at the end of the growing season, ranged between 16 and 26 t DM ha(-1). The model approach and its predictions are discussed. (C) 2000 Elsevier Science B.V. All rights reserved.