[1] We sought to determine the effect of elevated atmospheric CO2 on mineral weathering reactions in midlatitude carbonate-bearing forest soils of differing nutrient availability. Increased plant growth and soil respiration under elevated atmospheric CO2 suggest increased rates of carbon cycling, which may affect mineral weathering. A randomized complete block experiment was conducted, where as...

Elevated carbon dioxide (CO2) in leaves closes stomatal apertures. Research has shown key functions of the β-carbonic anhydrases (βCA1 and βCA4) in rapid CO2-induced stomatal movements by catalytic transmission of the CO2 signal in guard cells. However, the underlying mechanisms remain unclear, because initial studies indicate that these Arabidopsis (Arabidopsis thaliana) βCAs are targeted to d...

We have measured the metabolic activity in the vascularly isolated, salineperfused swimbladder of the eel (Anguilla anguilla) in order to investigate the pathways for CO2 formation in the gas gland tissue. Concentrations of O2, CO2, glucose and lactate were measured in the arterial inflow and venous outflow of the swimbladder, and metabolic rates were calculated by the direct Fick principle. 1....

Understanding functional trait distributions among organisms can inform impacts on and responses to environmental change. In marine systems, only 1% of dissolved inorganic carbon in seawater exists as CO2. Thus the majority of marine macrophytes not only passively access CO2 for photosynthesis, but also actively transport CO2 and the more common bicarbonate (HCO3-, 92% of seawater dissolved ino...

Ruiz, Ofelia S., R. Brooks Robey, Yi-Yong Qiu, Long Jiang Wang, Cheng Jin Li, Jianfei Ma, and Jose A. L. Arruda. Regulation of the renal Na-HCO3 cotransporter. XI. Signal transduction underlying CO2 stimulation. Am. J. Physiol. 277 (Renal Physiol. 46): F580–F586, 1999.—We have previously shown that CO2 stimulation of the renal Na-HCO3 cotransporter (NBC) activity is abrogated by general inhibit...

Chemolithoautotrophic bacteria grow in habitats with a variety of dissolved inorganic carbon (DIC) concentrations and are likely to have transport-related adaptations to DIC scarcity. Carbon-concentrating mechanisms (CCMs) are present in many species of cyanobacteria, enabling them to grow in the presence of low concentrations of CO2 by utilizing bicarbonate transporters and CO2 traps to genera...

Karenia mikimotoi is a widespread, toxic and non-calcifying dinoflagellate, which can release and produce ichthyotoxins and hemolytic toxins affecting the food web within the area of its bloom. Shifts in the physiological characteristics of K. mikimotoi due to CO2-induced seawater acidification could alter the occurrence, severity and impacts of harmful algal blooms (HABs). Here, we investigate...

Previous studies that have evaluated the Na(+)-H+ antiporter in cells from hypertensive subjects were generally performed under conditions in which HCO3-CO2, the physiological buffer system, was absent from the assay media. The objective of this study was to evaluate the activity of the Na(+)-H+ antiporter and that of the Na(+)-dependent and Na(+)-independent Cl(-)-HCO3- exchangers in cells ass...

Atmospheric mineral aerosols contain CaCO3 as a reactive component. A novel method to produce CaCO3 aerosol was developed by spraying Ca(HCO3)2 solution, which was generated from a CaCO3 suspension and CO2. By aerosol mass spectrometry the freshly sprayed and dried aerosol was characterized to consist of pure Ca(HCO3)2 which under annealing in a tube furnace transformed into CaCO3. Transmission...

We present results from a field study of inorganic carbon (C) acquisition by Ross Sea phytoplankton during Phaeocystis-dominated early season blooms. Isotope disequilibrium experiments revealed that HCO3 ) was the primary inorganic C source for photosynthesis in all phytoplankton assemblages. From these experiments, we also derived relative enhancement factors for HCO3 ) ⁄CO2 interconversion as...