Landscape Metrics and Land-Use Patterns of Energy Crops in the Agricultural Landscape

Energy crops are a new player in the traditional agricultural landscape. The present paper analyses the land uses surrounding and the spatial characteristics of the main energy crops in Sweden (willow, poplar, hybrid aspen and reed canary grass) compared to traditional agricultural crops during the period 2006-2018. Spatial metrics (number of shape characterising points, shape index and rectangularity ratio) are calculated for each field, as well as the nearby land uses at varying distances, at radius: 500 m, 1000 m, 2000 m and 5000 m. A total of 1560 energy crop fields are studied in the 2006 dataset and 3416 fields in the 2018 dataset, which are compared to 58,246 fields with cereal crops in 2006 and 131,354 fields in the 2018 dataset. Results show that, despite being established on previous agricultural land, energy crops present a different spatial profile compared to traditional agricultural crops. Field shapes present less complexity than before, and the overall spatial features become more regular with time in both cases of energy crops and cereals, suggesting an increasing trend in cost-efficient agricultural practices and planning. Important differences concerning land use diversity at different scales are found between plantations versus grasses. In general, willow plantations are located in agriculture-dominated areas (> 70% at 500 m, > 50% at 2000 m), whereas reed canary grass is in forest-dominated landscapes (> 30% at 500 m, > 60% at 2000 m); both contribute to diversifying existing land uses although with varying effects. The results of this study are a basis to assess the impacts of energy crops at landscape level and can translate into applications in energy policy and planning.