83 resultados para MASS SPECTROMETRY, GAS PHASE ACIDITY, GAS PHASE BASICITY
Resumo:
Geological, mineralogical and microbiological aspects of the methane cycle in water and sediments of different areas in the oceans are under consideration in the monograph. Original and published estimations of formation- and oxidation rates of methane with use of radioisotope and isotopic methods are given. The role of aerobic and anaerobic microbial oxidation of methane in production of organic matter and in formation of authigenic carbonates is considered. Particular attention is paid to processes of methane transformation in areas of its intensive input to the water column from deep-sea hydrothermal sources, mud volcanoes, and cold methane seeps.
Resumo:
The data files give the basic field and laboratory data on five ponds in the northeast Siberian Arctic tundra on Samoylov. The files contain water and soil temperature data of the ponds, methane fluxes, measured with closed chambers in the centres without vascular plants and the margins with vascular plants, the contribution of plant mediated fluxes on total methane fluxes, the gas concentrations (methane and dissolved inorganic carbon, oxygen) in the soil and the water column of the ponds, microbial activities (methane production, methane oxidation, aerobic and anaerobic carbon dioxide production), total carbon pools in the different horizons of the bottom soils, soil bulk density, soil substance density, and soil porosity.
Resumo:
Ne, Ar, Kr, Xe, and K2O were measured in representative samples of holocrystalline basalt from DSDP Hole 504B. No hiatus in inert gas abundance is recognized at the base of the "oxic" alteration zone and the extent rather than the nature of alteration appears to determine these abundances. When the inert gas abundances are separately plotted against K2O, two distinct trends of loss emerge, one for alteration involving K-gain, the other for K-loss. Apparent whole-rock K-Ar ages are anomalous in the upper 50 m of basement, and below 300 m sub-basement. In the intervening zone of basement, celadonization adds sufficient potassium and eliminates enough "primary" 40Ar early in the history of the basalts for "excess" 40Ar to become subordinate to radiogenic 40Ar in basalts showing potassium enrichment greater than 0.2%. Stratigraphically correct K-Ar ages are obtained, therefore, from K-enriched basalts of the oxic alteration zone.
Resumo:
The effects of CO2-induced seawater acidification on plankton communities were also addressed in a series of 3 mesocosm experiments, called the Pelagic Ecosystem CO2 Enrichment (PeECE I-III) studies, which were conducted in the Large-Scale Mesocosm Facilities of the University of Bergen, Norway in 2001, 2003 and 2005, respectively. Each experiment consisted of 9 mesocosms, in which CO2 was manipulated to initial concentrations of 190, 350 and 750 µatm in 2001 and 2003, and 350, 700 and 1050 µatm in 2005. The present dataset concerns PeECE III.