The effects of H2 gas treatment of an agricultural soil cultivated previously with a mixture of clover (Trifolium pratense) and alfalfa (Medicago sativa) on CO2 dynamics and microbial activity and composition were analyzed. The H2 emission rate of 250 nmol H2 g K1 soil h was similar to the upper limit of estimated H2 amounts emitted from N2 fixing nodules into the surrounding soil ([Dong, Z., L...

Introduction Hydrogen as a fuel has recently been an important issue due to developments in fuel cell technology. Hydrogen production from sustainable sources, e.g. biomass, is gaining attention for a CO2 neutral energy supply. Recent developments in flash pyrolysis technologies make it possible to convert lignocellulosic biomass efficiently to a bio-oil, which is easier for handling and transp...

Tillage is a common agricultural practice affecting soil structure and biogeochemistry. To evaluate how tillage affects soil microbial CO2 fixation, we incubated and continuously labelled samples from two paddy soils and two upland soils subjected to simulated conventional tillage (CT) and no-tillage (NT) treatments. Results showed that CO2 fixation ((14)C-SOC) in CT soils was significantly hig...

The key components of crassulacean acid metabolism (CAM) - nocturnal fixation of atmospheric CO2 and its processing via Rubisco in the subsequent light period - are now reasonably well understood in terms of the biochemical reactions defining this water-saving mode of carbon assimilation. Phenotypically, however, the degree to which plants engage in the CAM cycle relative to regular C3 photosyn...

BACKGROUND AND AIMS White lupin is highly adapted to growth in a low-P environment. The objective of the present study was to evaluate whether white lupin grown under P-stress has adaptations in nodulation and N2 fixation that facilitate continued functioning. METHODS Nodulated plants were grown in silica sand supplied with N-free nutrient solution containing 0 to 0.5 mm P. At 21 and 37 d aft...

We investigated carbon acquisition by the N2-fixing cyanobacterium Trichodesmium IMS101 in response to CO2 levels of 15.1, 37.5, and 101.3 Pa (equivalent to 150, 370, and 1000 ppm). In these acclimations, growth rates as well as cellular C and N contents were measured. In vivo activities of carbonic anhydrase (CA), photosynthetic O2 evolution, and CO2 and HCO { 3 fluxes were measured using memb...

Following field observations of increased photosynthesis at increased rates of sediment flushing in sandy sediments, we conducted a series of laboratory experiments to elucidate the mechanism behind these observations. Column experiments in which water was pumped though sand at rates ranging from 0 to 613 L m22 d21 showed that carbon (C) fixation, as measured using carbon-14 (14C) incorporation...

A thermophilic cyanobacterium named Thermosynechococcus CL–1 (TCL–1) was cultivated in the flat plate photobioreactors under strong illumination with dense culture to examine the effects of nutrient concentrations on the biomass production, CO2 fixation, and the potential as the feedstock for bioethanol production. The results show that concentrations of Na, NO3, and CaCl2•2H2O, should be decre...

CO2/pH perturbation experiments were carried out under two different pCO2 levels (39.3 and 101.3 Pa) to evaluate effects of CO2-induced ocean acidification on the marine diatom Phaeodactylum tricornutum. After acclimation (>20 generations) to ambient and elevated CO2 conditions (with corresponding pH values of 8.15 and 7.80, respectively), growth and photosynthetic carbon fixation rates of high...

Bio-Bag (Marion Laboratories, Kansas City, Mo.) type C is made up of a ziplock plastic bag which contains a Thayer-Martin plate and a crushable CO2-generating ampoule. This system was compared with the candle extinction jar, Gono-Pak (Nasco, Fort Atkinson, Wis.), and JEMBEC (GIBCO Diagnostics, Lawrence, Mass.) systems to determine their efficiency and reliability for the isolation of Neisseria ...