Journal of Conference Abstracts

Methane from West Siberian Swamps: Emission to the Atmosphere, Concentration and Transport in Liquid Phase

G. A. Makhov & N. M. Bazhin (bazhin@kinetics.nsk.su)

Institute of Chemical Kinetics and Combustion, Novosibirsk, 630090, Russia.

Methane emission from West Siberian swamps was studied during the summers of 1993-1996. The programme included: (1) methane emission measurements at various places using a standard camera method, (2) methane emission measurements at various places using an automatic camera method, (3) methane concentration measurements as a function of depth in water phase, (4) time dependence in water phase using a specially introduced tracer (SF6), (5) gas bubble composition measurements, and (6) methane concentration measurements in the gas phase.

Average methane emission from West Siberian swamps is equal 5.4 g m^-2 h^-1. Total annual emission from West Siberian swamps to the atmosphere was estimated as 13.6 Tg yr^-1. The automatic camera proved very useful for making methane emission measurements, giving results that were similar to those obtained using other methods. A very simple method was developed for making methane concentration measurements in swamp water with high resolution (3 cm). The methane concentration at depths greater than 0.5 m is high, approaching saturation at atmospheric pressure. Gas bubbles taken from the depth of 30-40 cm had the following composition: CH₄, 4-38 %; CO₂, 4-6 %; O₂ + Ar, 1-2 %; N₂, remainder. Gas bubble composition was correlated with methane emission from shallow places. Finally, SF6 concentration and evolution demonstrate transport of gases by diffusion and by bubbles in swamp water.

Using the Crystal Lattice of Minerals to Assess the Buffering Capacity of Rock Throughout the Kola Peninsula

A. Malinovsky (sharov@alphais.inep.ksc.ru) & A. Moiseenko (tatyana@alphais.inep.ksc.ru)

Institute of North Industrial Ecology Problems,Kola Science Centre,
Russian Academy of Science, 14 Fersman Str., Apatity, Murmansk Region, 184200, Russia.

One of the main factors determining stability of a territory subjected to water acidification is the buffering capacity of the watersheds rocks. At present its assessment is mostly carried out using relative criteria such as total content of alkaline and alkaline-earth elements (Na₂O+K₂O+CaO+MgO) or as a ratio of base cations to the most inert oxides (like AL₂O₃), or using experimental methods (Basalaev, 1996). These approaches are not free from disadvantages. One disadvantage is that it is impossible to take into account the mineralogical features of rocks and character of structural connections in minerals. Another disadvantage is that experimental methods can be expensive and labour-intensive.

To assess the buffering capacity throughout the Kola Peninsula, we used parameters such as the magnitude of energy for a mineral crystal lattice. The magnitude of energy for a mineral crystal lattice is determined by summing the energies in proportion to their volume in the rock, which will characterize the degree of sensitivity to chemical weathering processes. Power analyses enable the characterization of minerals susceptible to chemical conversions at the most external impacts. To assess the degree of stability of a territory to acid loads only the data on quantitative mineralogical composition of the investigated area is needed. The magnitude of energy for a mineral crystal lattice was used earlier during the description of laws of metasomatic processes and assessment of the thermodynamic stability of minerals. Therefore, accumulated experimental data and produced methods of theoretical account (Kazichin, 1968), permit with sufficient accuracy, the calculation of the magnitudes of energy for crystal lattices of almost all main minerals.

A scheme of rock spreading, with different mineral compositions, for a territory in the Kola peninsula was created using energy magnitudes of mineral crystal lattices. This scheme satisfactorily reflects the stability of rocks to processes of chemical weathering, and correlates well with the pH of surface waters received at the monitoring site in the region.

References

Basalaev A., Kasikov A. & Smirnov D. 3rd International Barents Symp., J. Conf. Abs., p. 19. (1996).

Kazichin U. & Rudnik V. Manual to calculation of substance balance and internal energy in metasomatic rock forming (1968).

Moiseenko T. Acidification and pollution by heavy metals of surface waters on Kola North (1991).