Energy crops in marginal areas: Scenario-based assessment through ecosystem services, as support to sustainable development

摘要

Starting from the identification of marginal areas, this work presents a possible physical-mathematical approach as a support to landscape planning, based on the pragmatic determination of the predictable environmental effects connected to land use changes (LUC) and related to objective and quantitative ecological indicators for environmental impact assessment."Fringe areas", which are more suitable to change in a medium-short time frame, were determined through a spatial multicriteria decision analysis (S-MCDA) process. Three land use changes scenarios were identified and analysed, namely: the current situation, energy crop cultivation in marginal lands, and the possible abandonment of lands such as these. Energy crop cultivation in marginal lands is widely considered to be a useful opportunity for farmers, against the progressive risk of under-utilization or abandonment; nevertheless, the large areas needed can cause important environmental side-effects. In order to assess the possible variations in environmental components in the ex-ante planning phase, scenarios were assessed in terms of habitat and biodiversity ecosystems services (using both monetary and indexes approach), focusing also on possible environmental fragmentation analysis by means of landscape metrics, which are simple measures used to deepen landscape configuration and structure.The S-MCDA process allowed about 10% of the study area with less favourable environmental conditions to be defined, where land use change is desirable in a medium-short time frame. For the energy crops scenario, the ecosystem services (ESs) approach highlights positive repercussions in terms of habitat quality and biodiversity value. Similar trends are highlighted by different ESs assessment methods adopted (monetary and indexes), confirming themselves. Also, landscape pattern analysis confirmed positive habitat connectivity trends: the delineation of fringe areas has preserved, in energy crops scenario, natural and semi-natural classes, reducing the risk of disturbance with respect to the biodiversity and habitat. This condition assumes that adopted S-MCDA method can contribute positively and significantly to the definition of LUC scenarios and land management.In conclusion, marginal lands can become an opportunity to improve socio-economic conditions and to enhance land image, while respecting the environment. LUC scenarios building, and their assessment by means of ecological indicators become a dynamic and structured tool in the land use planning/management process to support decision maker choices and to re-calibrate interventions, with the aim of contributing to sustainable policies of land management (ecological corridors, compensation and / or mitigation measures, etc.), emphasizing land sustainable management benefits (such as climate change adaptation or disaster risk reduction).