Volcanic aerosols from the 1991 Mount Pinatubo eruption greatly increased diffuse radiation worldwide for the following 2 years. We estimated that this increase in diffuse radiation alone enhanced noontime photosynthesis of a deciduous forest by 23% in 1992 and 8% in 1993 under cloudless conditions. This finding indicates that the aerosol-induced increase in diffuse radiation by the volcano enh...

Major sedimentary nutrient cycles Phosphorus cycle Sulphur cycle Major gaseous cycles Nitrogen Cycle Carbon Cycle Ammonification Nitrification Nitrogen fixation Symbiotic nitrogen fixation Non-symbiotic nitrogen fixation Photosynthesis Light reaction Dark reaction Carbon dioxide cycle Micronutrients Plant uptake of trace elements (essential and non-essential) Factors influencing micronutrient u...

Ocean uptake of anthropogenic CO2 reduces pH and saturation state of calcium carbonate materials of seawater, which could reduce the calcification rate of some marine organisms, triggering a negative feedback on the growth of atmospheric CO2. We quantify the effect of this CO2-calcification feedback by conducting a series of Earth system model simulations that incorporate different parameteriza...

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Chemoautotrophic symbioses, in which endosymbiotic bacteria are the major source of organic carbon for the host, are found in marine habitats where sulfide and oxygen coexist. The purpose of this study was to determine the influence of pH, alternate sulfur sources, and electron acceptors on carbon fixation and to investigate which form(s) of inorganic carbon is taken up and fixed by the gamma-p...

The strong advances in synthetic biology enable the engineering of novel functions and complex biological features in unprecedented ways, such as implementing synthetic autotrophic metabolism into heterotrophic hosts. A key challenge for the sustainable production of fuels and chemicals entails the engineering of synthetic autotrophic organisms that can effectively and efficiently fix carbon di...

Elevated atmospheric carbon dioxide (CO2) can affect both the quantity and quality of plant tissues produced, which will impact the cycling and storage of carbon (C) within plant/soil systems and thus the rate of CO2 release back to the atmosphere. Research is needed to more accurately quantify the effects of elevated CO2 and associated feedbacks on soil CO2 efflux in order to predict the poten...

A dynamic numerical model was developed to predict the biomass concentration, pH, and carbon dioxide fixation rate in the continuous culture of cyanobacteria in a photobioreactor. The model is based on the growth rate equation of microalgae combined with mass transfer equations for gas and liquid phases in the photobioreactor as well as thermodynamic equilibrium of inorganic carbon ions in the ...

C(4) photosynthesis has evolved more than 60 times as a carbon-concentrating mechanism to augment the ancestral C(3) photosynthetic pathway. The rate and the efficiency of photosynthesis are greater in the C(4) than C(3) type under atmospheric CO(2) depletion, high light and temperature, suggesting these factors as important selective agents. This hypothesis is consistent with comparative analy...

soil organic carbon is a key factor in productivity and quality of soil and environment particularly in semi arid regions. in this article, the role of farm soil organic matter management in soil and in land is discussed. the variability of soil organic carbon in drylands is mainly controlled by tillage and crop residue management. results of this study indicated that usage of correct tillage m...