title: Computing the biomass potentials for maize and two alternative energy crops, triticale and cup plant (Silphium perfoliatumL.), with the crop model BioSTAR in the region of Hannover (Germany).
abstract: BACKGROUND
  Lower Saxony (Germany) has the highest installed electric capacity from biogas in Germany. Most of this electricity is generated with maize. Reasons for this are the high yields and the economic incentive. In parts of Lower Saxony, an expansion of maize cultivation has led to ecological problems and a negative image of bioenergy as such. Winter triticale and cup plant have both shown their suitability as alternative energy crops for biogas production and could help to reduce maize cultivation.
  
  
  RESULTS
  The model Biomass Simulation Tool for Agricultural Resources (BioSTAR) has been validated with observed yield data from the region of Hannover for the cultures maize and winter wheat. Predicted yields for the cultures show satisfactory error values of 9.36% (maize) and 11.5% (winter wheat). Correlations with observed data are significant (P< 0.01) withR= 0.75 for maize and 0.6 for winter wheat. Biomass potential calculations for triticale and cup plant have shown both crops to be high yielding and a promising alternative to maize in the region of Hanover and other places in Lower Saxony.
  
  
  CONCLUSIONS
  The model BioSTAR simulated yields for maize and winter wheat in the region of Hannover at a good overall level of accuracy (combined error 10.4%). Due to input data aggregation, individual years show high errors though (up to 30%). Nevertheless, the BioSTAR crop model has proven to be a functioning tool for the prediction of agricultural biomass potentials under varying environmental and crop management frame conditions.
authors.affiliation: Department of Cartography, GIS and Remote Sensing, Research Project 'BIS', University of Göttingen, Goldschmidtstraße 5, Göttingen, 37077 Germany.
authors.forename: Roland
authors.initials: R
authors.lastname: Bauböck
authors.affiliation: Interdisciplinary Centre of Sustainable Development, Research Project 'BIS', University of Göttingen, Goldschmidtstraße 1, Göttingen, 37077 Germany.
authors.forename: Marianne
authors.initials: M
authors.lastname: Karpenstein-Machan
authors.affiliation: Department of Cartography, GIS and Remote Sensing, Research Project 'BIS', University of Göttingen, Goldschmidtstraße 5, Göttingen, 37077 Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Kappas
keywords: Alternative energy crops; BioSTAR; Biomass potentials; Integrative concepts