title: New feed sources key to ambitious climate targets.
abstract: Net carbon sinks capable of avoiding dangerous perturbation of the climate system and preventing ocean acidification have been identified, but they are likely to be limited by resource constraints (Nature 463:747-756, 2010). Land scarcity already creates tension between food security and bioenergy production, and this competition is likely to intensify as populations and the effects of climate change expand. Despite research into microalgae as a next-generation energy source, the land-sparing consequences of alternative sources of livestock feed have been overlooked. Here we use the FeliX model to quantify emissions pathways when microalgae is used as a feedstock to free up to 2 billion hectares of land currently used for pasture and feed crops. Forest plantations established on these areas can conceivably meet 50 % of global primary energy demand, resulting in emissions mitigation from the energy and LULUC sectors of up to 544 [Formula: see text] 107 PgC by 2100. Further emissions reductions from carbon capture and sequestration (CCS) technology can reduce global atmospheric carbon concentrations close to preindustrial levels by the end of the present century. Though previously thought unattainable, carbon sinks and climate change mitigation of this magnitude are well within the bounds of technological feasibility.
authors.affiliation: Ecosystems Services and Management, International Institute for Applied Systems Analysis, Schlossplatz 1, Laxenburg, Austria.
authors.forename: Brian J
authors.identifier: 0000-0003-1689-2309
authors.initials: BJ
authors.lastname: Walsh
authors.affiliation: Ecosystems Services and Management, International Institute for Applied Systems Analysis, Schlossplatz 1, Laxenburg, Austria.
authors.forename: Felicjan
authors.initials: F
authors.lastname: Rydzak
authors.affiliation: Ecosystems Services and Management, International Institute for Applied Systems Analysis, Schlossplatz 1, Laxenburg, Austria.
authors.forename: Amanda
authors.initials: A
authors.lastname: Palazzo
authors.affiliation: Ecosystems Services and Management, International Institute for Applied Systems Analysis, Schlossplatz 1, Laxenburg, Austria.
authors.forename: Florian
authors.initials: F
authors.lastname: Kraxner
authors.affiliation: Commonwealth Scientific and Industrial Research Organisation, Brisbane, Australia.
authors.forename: Mario
authors.initials: M
authors.lastname: Herrero
authors.affiliation: Algae Biotechnology Laboratory, School of Agriculture and Food Sciences, The University of Queensland, Brisbane, Australia.
authors.forename: Peer M
authors.initials: PM
authors.lastname: Schenk
authors.affiliation: Laboratoire des Sciences du Climat et de L'Environnement, CEA-CNRS-UVSQ, Gif-sur-Yvette, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Ciais
authors.affiliation: University of Antwerp, Wilrijk, Belgium.
authors.forename: Ivan A
authors.initials: IA
authors.lastname: Janssens
authors.affiliation: CSIC, Global Ecology Unit CREAF-CSIC-UAB, Cerdanyola del Valles (Catalonia), Spain ; CREAF, Cerdanyola del Valles (Catalonia), Spain.
authors.forename: Josep
authors.initials: J
authors.lastname: Peñuelas
authors.affiliation: Ecosystems Services and Management, International Institute for Applied Systems Analysis, Schlossplatz 1, Laxenburg, Austria.
authors.forename: Anneliese
authors.initials: A
authors.lastname: Niederl-Schmidinger
authors.affiliation: Ecosystems Services and Management, International Institute for Applied Systems Analysis, Schlossplatz 1, Laxenburg, Austria.
authors.forename: Michael
authors.initials: M
authors.lastname: Obersteiner
keywords: BECCS; Biofuels; CCS; Climate change; FeliX; Food security; Livestock; Protein