elevated atmospheric carbon dioxide and other green house gases have increased the earth temperature in recent century, which it affects all biochemistry cycles in soils. to examine the effect of atmospheric co2 concentration and temperature on n forms in soil solution in a calcareous soil, an experiment was conducted in a completely randomized design with factorial arrangement in the laborator...

Unbalanced production of atmospheric CO(2) constitutes a major challenge to global sustainability. Technologies have thus been developed for enhanced biological carbon fixation (also referred to as CO(2) mitigation), and one of the most promising capitalizes on microalgae. However, the "best bioreactor", which would be able to achieve maximum productivity and maximum energy efficiency under a g...

Photosynthetic data collected from Pisum sativum L. and Phaseolus vulgaris L. plants at different stages of development were related to symbiotic N(2) fixation in the root nodules. The net carbon exchange rate of each leaf varied directly with carboxylation efficiency and inversely with the CO(2) compensation point. Net carbon exchange of the lowest leaves reputed to supply fixed carbon to root...

The effect of 3,3-dichloro-2-(dihydroxyphosphinoylmethyl)propenoate (DCDP), an analog of phosphoenolpyruvate (PEP), on PEP carboxylase activity in crude leaf extracts and on photosynthesis of excised leaves was examined. DCDP is an effective inhibitor of PEP carboxylase from Zea mays or Pancum miliaceum; 50% inhibition was obtained at 70 or 350 micromolar, respectively, in the presence of I mil...

Rapidly increasing levels of atmospheric CO2 and other greenhouse gases (GHGs) initiate unprecedented changes in climate systems, leading to severe ecological economic disruptions. Climate change mitigation is possible through a reduction net GHG emission by the process carbon sequestration. Storage stable solid form direct indirect fixation soil sequestration can result an annual growth rate 0...

δCO2 measured in Antarctic ice cores provides constraints on oceanic and terrestrial carbon cycle processes linked with millennial-scale changes in atmospheric CO2. However, the interpretation of δCO2 is not straightforward. Using carbon isotope-enabled versions of the LOVECLIM and Bern3D models, we perform a set of sensitivity experiments in which the formation rates of North Atlantic Deep Wat...

It is unclear why atmospheric oxygen remained trapped at low levels for more than 1.5 billion years following the Paleoproterozoic Great Oxidation Event. Here, we use models for erosion, weathering and biogeochemical cycling to show that this can be explained by the tectonic recycling of previously accumulated sedimentary organic carbon, combined with the oxygen sensitivity of oxidative weather...

Photosynthesis in plants converts the energy of sunlight into chemical energy. Although photosynthesis involves many proteins and catalytic processes, it often is described as two sets of reactions: the light-dependent reactions and the carbonfixing reactions. Plants do not have a monopoly on photosynthesis, which also occurs in other photosynthetic eukaryotes and several species of bacteria. I...

The hydrogen (H₂) cycle associated with the dinitrogen (N₂) fixation process was studied in laboratory cultures of the marine cyanobacterium Crocosphaera watsonii. The rates of H₂ production and acetylene (C₂H₂) reduction were continuously measured over the diel cycle with simultaneous measurements of fast repetition rate fluorometry and dissolved oxygen. The maximum rate of H₂ production was c...