Modelled effects of rising CO2 concentration and climate change on native perennial grass and sown grass-legume pastures

Abstract

CR Climate Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials CR 42:65-78 (2010) - DOI: https://doi.org/10.3354/cr00863 Modelled effects of rising CO2 concentration and climate change on native perennial grass and sown grass-legume pastures M. P. Perring1,4,*, B. R. Cullen2, I. R. Johnson3, M. J. Hovenden1 1School of Plant Science, University of Tasmania, Private Bag 55, Hobart, Tasmania 7001, Australia 2Melbourne School of Land and Environment, University of Melbourne, Parkville, Victoria 3010, Australia 3IMJ Consultants, Armidale, New South Wales 2350, Australia 4Present address: Ecosystem Restoration Lab, School of Plant Biology (M090), The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia *Email: michael.perring@uwa.edu.au ABSTRACT: Native perennial grass and sown grass-legume pastures are an important agricultural and environmental resource. We investigated the impact of rising carbon dioxide concentration ([CO2]) and projected climate changes on these pasture ecosystems in southeastern Tasmania, Australia, using a biophysical simulation model, EcoMod. The model consists of interdependent modules that describe soil physicochemical and hydrological characteristics, and pasture growth and senescence, with fluxes described by empirical and mechanistic equations. Our simulations showed that in native pastures, projected climate change increased the biomass of C4 grasses, with limited impact upon C3 grasses, a trend reversed by rising [CO2]. In sown pastures, projected climate change decreased the biomass of perennial rye grass Lolium perenne and total biomass markedly by 2070, whilst subterranean clover Trifolium subterraneum biomass increased. Subterranean clover biomass changed little with increased [CO2] alone, whereas perennial rye grass biomass increased. Responses across pastures reflected species’ tolerances to environmental factors, with projected climate change generally having more of an impact on biomass than rising [CO2]. Changes in both [CO2] and climate led to a reduction in protein content and digestibility. Soil inorganic nutrient concentrations decreased with increasing [CO2] and increased with projected climate change. Further simulations should investigate whether these patterns are robust for different sites and alternative environmental futures. Our results reinforce the need to pursue adaptation strategies in response to environmental change in order to maintain productive pasture ecosystems. KEY WORDS: Lolium perenne · Ecosystem model · Simulation · Nutrient availability · Productivity · Tasmania Full text in pdf format PreviousNextCite this article as: Perring MP, Cullen BR, Johnson IR, Hovenden MJ (2010) Modelled effects of rising CO2 concentration and climate change on native perennial grass and sown grass-legume pastures. Clim Res 42:65-78. https://doi.org/10.3354/cr00863Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in CR Vol. 42, No. 1. Online publication date: June 03, 2010 Print ISSN: 0936-577X; Online ISSN: 1616-1572 Copyright © 2010 Inter-Research.