Sosnin, Aleksandr (2009) Organic Matter Mineralization and Trace Gas Turnover in Northeast Siberian Permafrost Deposits. (Master thesis), St. Petersburg State University ; University of Bremen, St. Petersburg, Russia ; Bremen, 38 pp.

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Abstract

Permafrost rocks are one of the potential of large storage carbon dioxide and methane, presumably the concentration of carbon in the range from 700 to 1500 Gt, which is considered by some authors to stimulate the processes of global warming. Perhaps quantity of this element is correct, but under what conditions they are a threat? For better understanding this question firstly we need more details about mineralization, it helps us apply results of laboratory work in master thesis.
Mineralization is a process of turning organic matter (plant and animal residues) in a simple inorganic (CO2, NH3, CaCO3, etc.). One of the most simple example of this process occurs in soil.
Object of study is the allocation of carbon dioxide (and methane) from the permafrost layer of sediments of the Lena delta river. Thus, the aim of the work is assessment the possible emission of carbon dioxide in permafrost sediments of the Lena delta river (Samoylov and Kurungnakh islands).
The work assumes the following tasks:
1. to improve our understanding on organic matter mineralization in the carbon rich northeast Siberian permafrost;
2. to determine the effect of geographical conditions on the rate of mineralization;
3. to measure the speed of mineralization of organic matter in anaerobic and aerobic conditions in permafrost sediments of the Delta Lena;
4. to measure total organic carbon concentrations in the samples;
5. to identify the dependence gas emission on the quantity of organic carbon concentration in the samples;
Analysis of geographical conditions, climate and soil as the main factors influencing the persistence and modification of permafrost rocks is presented in the first chapter. Special attention is paid to the characteristics of permafrost soils and sediments in the Lena Delta River. The second chapter describes the materials and methods which were used for experiment. During laboratory research 1000 measurements of concentration trace gases in permafrost samples have been made. The results of the measurements and its interpretation are offered in the third chapter.
During of research work the following methods have been used: comparative method, laboratory method: measuring the volume of CO2 and CH4 using a gas chromatograph (GC), revealing the concentration of total organic carbon and nitrogen, the measurement of pH value in the samples.
It should be noted that the issue of allocation of carbon dioxide and methane from permafrost deposits attracted much attention in scientific community. In Germany this problem are described in works L. Kutzbach, E.-M. Pfeiffer, D. Wagner, C. Knoblauch. In foreign countries, this concern relates with the possible impact on global climate, and in accordance with the possible catastrophic consequences for humanity.
In Russia, investigation in frame of this question mostly connected with engineering, as in the cities built on the Siberian permafrost soils a large proportion of the population, and the study of permafrost, it is necessary for security, maintaining economic activity, etc. Therefore, scientific organization in Siberia and other cities (traditionally St. Petersburg, Moscow) have given sufficient attention to research in this area.
As a result of the experiment and data analysis determined the relationship of the allocation of greenhouse gases from permafrost deposits of organic material, its age, and geographical conditions of occurrence. The data presented in the paper can be use for construction mathematical models, which usually use averaged values of emissions of carbon dioxide, not taking into account the specific geographical conditions deltas of Siberian River. Also, the material will be useful to make prediction, and further studies in emissions of gases.

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