Forest bioenergy harvesting changes carbon balance and risks biodiversity in boreal forest landscapes

Abstract

Climate solutions relying on forest bioenergy may be in conflict with carbon sequestration and storage by forests as well as conservation of biodiversity. We quantified effects of forest-residue harvesting for bioenergy on both forest carbon balance and biodiversity in a boreal forest landscape. Through a modeling framework, we simulated forest development in four real watersheds with three scenarios: (i) with and (ii) without forest-residue harvesting and (iii) set aside to study the conservation potential of these landscapes in the future without management. We simulated changes in the forest carbon stocks and in the quality and quantity of deadwood resources for 100 years and combined this information with the information on species habitat associations based on expert judgements. In this study, current practices of slash and stump harvesting reduced forest carbon stocks and deadwood volumes at the landscape scale and, consequently, halved the emissions savings that can be obtained with bioenergy. In addition, logging-residue harvesting reduced 15%–21% of the combined species conservation capacity of the landscape for red-listed, saproxylic species compared with forest management without bioenergy harvesting. Furthermore, the results indicated a potential conflict between areas of high bioenergy potential and high conservation potential.