In this study we explore the use of natural CO2 emissions in Yellowstone National Park (YNP) in Wyoming, USA to study responses of natural vegetation to elevated CO2 levels. Radiocarbon (14C) analysis of leaf biomass from a conifer (Pinus contortus; lodgepole pine) and an invasive, non-native herb (Linaria dalmatica; Dalmation toadflax) was used to trace the inputs of vent CO2 and quantify assi...

Trees exposed to elevated CO2 partial pressure ([CO2]) generally show increased rates of photosynthesis and growth, but effects on leaf respiration are more variable. The causes of this variable response are unresolved. We grew 12-year-old sweetgum trees (Liquidambar styraciflua L.) in a Free-Air CO2 Enrichment (FACE) facility in ambient [CO2] (37/44 Pa daytime/nighttime) and elevated [CO2] (57...

Elevated concentrations of atmospheric carbon dioxide ([CO2]) and tropospheric ozone ([O3]) have the potential to affect tree physiology and structure and hence forest water use, which has implications for climate feedbacks. We investigated how a 40% increase above ambient values in [CO2] and [O3], alone and in combination, affect tree water use of pure aspen and mixed aspen-birch forests in th...

Physiological control of stomatal conductance (Gs) permits plants to balance CO2-uptake for photosynthesis (PN) against water-loss, so optimizing water use efficiency (WUE). An increase in the atmospheric concentration of carbon dioxide ([CO2]) will result in a stimulation of PN and reduction of Gs in many plants, enhancing carbon gain while reducing water-loss. It has also been hypothesized th...

Rising levels of atmospheric CO2 are thought to increase C sinks in terrestrial ecosystems. The potential of these sinks to mitigate CO2 emissions, however, may be constrained by nutrients. By using metaanalysis, we found that elevated CO2 only causes accumulation of soil C when N is added at rates well above typical atmospheric N inputs. Similarly, elevated CO2 only enhances N2 fixation, the m...

Human activities are increasing the concentrations of atmospheric carbon dioxide ([CO2]) and tropospheric ozone ([O3]), potentially leading to changes in the quantity and chemical quality of leaf litter inputs to forest soils. Because the quality and quantity of labile and recalcitrant carbon (C) compounds influence forest productivity through changes in soil organic matter content, characteriz...

Elevated atmospheric concentrations of CO2 and O3 are known to alter the chemical composition of foliage, which in turn may affect the performance of herbivorous insects. We investigated the independent and interactive effects of CO2 and O3 on foliar quality of paper birch (Betula papyrifera Marshall) and the consequences of chemical changes for performance of the whitemarked tussock moth Orgyi...

The aim of this study was to investigate the effects of climate change on the radial growth, wood structure and chemistry of silver birch (Betula pendula Roth), trembling aspen (Populus tremuloides Michx.), paper birch (Betula papyrifera Marsh.), sugar maple (Acer saccharum Marsh.) and Norway spruce (Picea abies (L.) Karst.). The materials for this study were obtained from climate change studie...

The impact of elevated CO2 (1000μmol/mol) was assessed on the common weed, Arabidopsis thaliana (Landsberg erecta), which is used as a model plant system. Elevated CO2 stimulated relative growth rate (RGR) and leaf area gain of Arabidopsis beginning from the cotyledon stage and continuing through the juvenile stage. This early advantage in growth enabled the plants grown in elevated CO2 to gain...

Rice is arguably the most important food source on the planet and is consumed by over half of the world’s population. Considerable increases in yield are required over this century to continue feeding the world’s growing population. This meta-analysis synthesizes the research to date on rice responses to two elements of global change, rising atmospheric carbon dioxide concentration ([CO2]) and ...