Figure 5. Methodological approach of the energy-information-structure model (see Annex B ): a)Graph model of the interlinked energy carriers flowing in an agroecosystem. b) From the graph model, we can calculate the energy investment (E ), the energy information (I ), and the energy ‘imprint’ in the landscape structure (L ). c) The resulting mathematical model allows to calculate a three-dimensional relationship among E , I and L (as an example five land-cover typologies are represented), conforming a particular human-transformed landscape.