ARS | Publication request: Quantifying gaps in understanding of crop and ecosystem responses to elevated CO2

Submitted to: Plant Biology Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: May 1, 2012
Publication Date: July 20, 2012
Citation: Bishop, K., Leakey, A., Ainsworth, E.A. 2012. Quantifying gaps in understanding of crop and ecosystem responses to elevated CO2 [abstract]. Plant Biology Annual Meeting. Paper No. P23001.

Technical Abstract: The response of plants and ecosystems to rising atmospheric carbon dioxide concentration ([CO2]) plays a critical role in determining future food supply, future carbon storage in managed and natural ecosystems, and the magnitude of global climate change. Field experiments using both open-top chambers (OTC) and Free Air Concentration Enrichment (FACE) investigate the response of plants and ecosystems to rising [CO2] in relatively undisturbed, natural conditions and provide critical results for modeled projections of future global carbon balance and food supply. The objectives of this study are to: (a) determine the phylogenetic, geographic and climatic inference space of the 34 FACE and 62 OTC studies to date, and (b) use meta-analytic techniques to quantify how the photosynthetic and growth response of plants to elevated [CO2] varies along temperature, precipitation and nutrient gradients. Results show that experimentation to date has been strongly biased toward ecologically and economically important species in temperate climates. There is a lack of experimentation on natural and agricultural systems at low and high latitudes. Large gaps in knowledge also exist for a number of keystone species and genera, including those in Moraceae, Dipterocarpaceae and Mimosoideae families. Despite these limitations of the dataset from temperate experiments, there is significant variation in temperature and rainfall among experimental sites, which we use to test the hypothesis that temperature and water availability modulate the impact of elevated [CO2].