The Molecular Composition of Lignin as an Indicator of Subaqueous Permafrost Thawing

The concentration and molecular composition of phenols, lignin derivatives, were analyzed. The material for the study was sampled from bottom sediments and subaqueous perennial frozen rocks from a well drilled in the Buor-Khaya Gulf of the Laptev Sea. The analysis was undertaken on the basis of calculation of the molecular factor. The principal difference in the molecular composition of organic matter is shown. This difference is manifested in the decrease in the total concentration of the vanillic lignin derivatives in the thawed formations in comparison with the perennial frozen rocks. This phenomenon is explained by activation of the bacterial transformation of organic matter caused by thawing of the subaqueous permafrost. It was established that the weight percentage of lignin in the organic matter of the analyzed sediments is 17% C_org.

     

Transport of organic matter and clay minerals in estuaries of the Arctic sea (Experimental and Field Observations)

The behavior of clay minerals under different salinity conditions was studied during model experiments using clay mineral suspensions (bentonite and kaolinite) and organic substance solutions (chitosan, humic acids). It was shown that the kaolinite suspension was more stable and may migrate through the river-sea barrier, while the bentonite suspension coagulated even under 1–2‰ salinity. The influence of the organic matter’s nature on the stability of clay mineral suspensions and their ability to migrate through the marginal filter was discussed.     

Lithological and Geochemical Characteristics of Morpholithogenesis in Buor-Khaya Bay

Oceanology - The paper presents the general lithological and geochemical characteristics of subsea permafrost and thawed bottom sediments from three cores drilled in Buor-Khaya Bay. The...     

Distribution,Fluxes, and Balance of Particulate Organic Carbon in the Arctic Ocean

Oceanology - Particulate organic carbon is one of the major components of the carbon cycle in the ocean. In this study, an attempt to has been made construct a pattern of the distribution and...     

Interannual variability of the primary production and organic carbon fluxes in the Arctic seas of Russia

To estimate the response of the primary production to the climate warning, the trends of the production changes within 1998–2006 were considered in tests areas in the Barents, Kara, and Chukchi seas using satellite and field data. Both positive and negative trends were revealed with a general tendency to an increase in the primary production and in the extent of the organic carbon burial in the bottom sediments.     

Geochemical Typing of Organic Matter in the Bottom Sediments Based on the Molecular Composition of Saturated Aliphatic Hydrocarbons

Oceanology - The paper presents approaches to typing organic matter (OM) from bottom sediments based on molecular indicators and statistical analysis. The results of analyzing the molecular...