Setting priorities for land management to mitigate climate change
- Equal contributors
1 International Institute for Applied Systems Analysis, Ecosystem Services and Management Program, Schlossplatz 1, Laxenburg 2361, Austria
2 Johann Heinrich von Thünen-Institut, Institut für Agrarrelevante Klimaforschung, Bundesallee 50, Braunschweig 38116, Germany
3 Deutsches Zentrum für Luft- und Raumfahrt, Institut für Technische Thermodynamik, Pfaffenwaldring 38-40, Stuttgart 70569, Germany
4 CIRED - CNRS/EHESS, 45 bis avenue de la Belle Gabrielle, Nogent s/Marne 94736, France
5 Laboratoire des Sciences du Climat et de l'Environnement, Unité Mixte de Recherche CEA-CNRS, CE Orme des Merisiers, Gif sur Yvette, Cedex 91191, France
6 Georg-August-Universität Göttingen, Burckhardt-Institut, Waldbau und Waldökologie der gemäßigten Zonen, Büsgenweg 1, Göttingen 37077, Germany
7 Max-Planck-Institut für Biogeochemie, Postfach 100164, Jena 07701, Germany
Carbon Balance and Management 2012, 7:5 doi:10.1186/1750-0680-7-5Published: 16 March 2012
No consensus has been reached how to measure the effectiveness of climate change mitigation in the land-use sector and how to prioritize land use accordingly. We used the long-term cumulative and average sectorial C stocks in biomass, soil and products, C stock changes, the substitution of fossil energy and of energy-intensive products, and net present value (NPV) as evaluation criteria for the effectiveness of a hectare of productive land to mitigate climate change and produce economic returns. We evaluated land management options using real-life data of Thuringia, a region representative for central-western European conditions, and input from life cycle assessment, with a carbon-tracking model. We focused on solid biomass use for energy production.
In forestry, the traditional timber production was most economically viable and most climate-friendly due to an assumed recycling rate of 80% of wood products for bioenergy. Intensification towards "pure bioenergy production" would reduce the average sectorial C stocks and the C substitution and would turn NPV negative. In the forest conservation (non-use) option, the sectorial C stocks increased by 52% against timber production, which was not compensated by foregone wood products and C substitution. Among the cropland options wheat for food with straw use for energy, whole cereals for energy, and short rotation coppice for bioenergy the latter was most climate-friendly. However, specific subsidies or incentives for perennials would be needed to favour this option.
When using the harvested products as materials prior to energy use there is no climate argument to support intensification by switching from sawn-wood timber production towards energy-wood in forestry systems. A legal framework would be needed to ensure that harvested products are first used for raw materials prior to energy use. Only an effective recycling of biomaterials frees land for long-term sustained C sequestration by conservation. Reuse cascades avoid additional emissions from shifting production or intensification.