Annotated reference list of CH4 and CO2 flux measurementsfrom Russia mires

Atmospheric CO2 and CH4 are the effective greenhouse gases. The increase in the concentration of radiatively active gases such as CO2 and CH4 has the potential to increase surface temperature and affect climate on a global scale. The concentration of atmospheric methane has doubled over the last century from a preindustrial concentration of 0.7 ppmv to the current level of 1.7 ppmv. Because of the potential effects of increased atmospheric CO2 and CH4 on the global energy budget, considerable effort has recently been made to quantify terrestrial CO2 and CH4 sources and sinks. Natural wetlands are important sources of CH4 to the global atmosphere accounting for nearly 30% of the CH4 produced annually. Analysis of global CH4 emissions indicates that more than half of the annual wetland emission is from forested and nonforested wetlands from 50 to 70°N. Russia, Canada and Alaska are the major CH4 sources to the atmosphere from high-latitude soils of the Northern Hemisphere, responsible for 64%, 11%, and 7% of these net emissions, respectively. Estimates of the source and sink strength of boreal, subarctic, and arctic wetlands have received considerable attention in recent initiatives such as the 1988 Arctic Boundary Layer Experiment (ABLE) and the 1990 Canadian Northern Wetlands Study (NOWES). The results of these experiments have been published in dedicated volumes of the Journal of Geophysical Research and other well known scientific journals. Of course the reviews reflect mainly these papers. For example 21 out of the 25 CH4 flux estimates listed by Vourlitis and Oechel [1996] for arctic and subarctic ecosystems are from Alaska and 23 out of the 34 estimates of boreal wetland CH4 flux are derived from studies of Canadian boreal wetlands. Unfortunately reported estimates of CH4 flux extrapolated from plot-level arctic, subarctic, and boreal wetlands (50 to 70°N) range between ca. 25-35 TgCH4 /yr to as high as 65 TgCH4 /yr. The high dispersion probably reflect the relatively limited date base that was available for Russia. Significant amount of CO2 and CH4 flux research has been conducted in Russia over the past 10-20 years. But the results of these experiments have been published mainly in national Russian scientific journals as well as Proceedings and Abstracts of symposiums. Due to the uncertainty in the natural wetland CO2 and CH4 sources and sinks strengths, the aim of our paper is to review the publications which estimate CO2 and CH4 emissions in Russia and discuss how photosynthesis, respiration, methanogenesis, and methyltrophy are controlled here by their environment. Time span covered in this annotated bibliography is from the beginning of the 1990s up to now. The list contains both primary sources and reviews, which report data on carbon dioxide or methane flux densities. Topics not covered are consumption and production of СН4 and СО2 by soil microcosms, time trends for C pools in ecosystems, experimental studies of photoassimilation. While the list is not exhaustive, an effort has been made to mention publications of all known to the compiler research groups, which have been engaged in measurements of СО2 and СН4 fluxes at Russian mires. Totally, about 200 annotations are included. If the original source contains an authors' annotation, it is reproduced in the bibliography, sometimes with minor alterations. Otherwise, an annotation which summarizes methods and results of the study was written by the compiler. When we believed our own appraisals and comments on the original content to be desirable, they were inserted as footnotes.