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RASCHER
Short Title: RASCHER Project URL: http://igras.geonet.ru/cwg/projects.html#rascher Proposal URL: http://classic.ipy.org/development/eoi/proposal-details.php?id=262 Soils of Polar Regions are a very important membrane in bio-cryospheric interactions, regulating natural and human-induced processes in ecosystems and landscapes of the North Latitudes. The knowledge of positive and negative feedbacks in the system climate-vegetation-soil-permafrost are of the crucial significance for understanding and forecasting response of this system to global change. RASCHER addresses how climate variability and change can affect the soil systems of the polar (Subarctic and Arctic) regions and their sustainability. To provide accurate projections on the impact of climate change and increase of anthropogenic influence on these systems requires improved knowledge of its components and their linkages. Soil has both very inert and changeable parameters, which are altered differently because of climate change. RASCHER will mainly focus on the study of temporal change of labile soil characteristics (temperature, carbon fluxes and other gas fluxes, microbiota and microfauna) and of more stable soil characteristics (mineral composition, organic matter content and quality, morphological features, taxonomical status) in different kinds of frontiers (treeline, tundra-bog border, southern border of permafrost, contact zone of soil and permafrost table in a profile), which are expected to be changed first due to climate change. Together with climate-induced change the influence of the other regional and international processes shift of resource development, increased tourism and relevant infrastructure to the north on permafrost-affected soils will be studied. RASCHER will be based on both database analysis and field studies. The database on soil temperatures for dozens of meteorological stations of arctic and boreal regions for the period 50-100 years and the northern circumpolar soil database are already compiled and can be used for analysis. The field studies will be carried out in the different regions of Arctic and Subarctic during 2006-2008. To understand the effects of global change on northern polar soils firstly the long-term climatic trends and correlation of air and soil temperatures on the various depths will be carried out and the relevant models will be developed. Using the prognosis for climate change the spatial model of soil temperature change in northern polar latitudes will be elaborated. The potential development of northern industries, settlements and transport infrastructure (roads, pipelines) relevant to soil change will be forecasted together with social geographers and specialists in land management. The analysis of previously gained data on anthropogenic impact on permafrost-affected soils and field work in relevant human-changed environments will allow to elaborate the spatial prognostic model of anthropogenic change of Arctic and Subarctic soils. The Northern circumpolar soil database will help to differentiate this forecast related to kinds of soils and substrate. The role of thermal factor in composition and functioning of the biotic complex of tundra soils (microbiota, micro- and mesofauna) as well as the selective role of negative temperatures on the structure of soil microbiocenoses and the influence of cryogenesis on adaptive functions of soil microorganisms will be studied both in the field and in a laboratory using traditional and new (DNA analysis) methods. It allows comparing new data with results of studies carried out at the same locations 30-40 years ago and assessing if any climate-induced change of soil biota has taken place. The samples collected from the same places as 20 years ago will be analyzed for the 14C activity and the soil carbon renovation rates will be calculated (Cherkinsky-Brovkin model) and then will be compared with old samples to find out if it is any acceleration of carbon turnover due to global change. The frontier studies will concern the non-stability of soil thermic regimes, shrinking of isolated patches and the northward retreat of permafrost-affected soils, the assessments of possible soil change related to the vegetation transformation on the base of soil studies (carbon fluxes, humus quality, mineral composition, etc.) in different types of ecotones (forest-tundra, tundra-bog, forest-meadow, forest-bog, meadow-tundra). The other part of frontier studies is the detailed analysis of soil process at the interface of soil and permafrost tables. It concerns the study of the bio- and geochemical barrier on this interface and the study of the process of cryogenic lateral transportation at the contact zone of soil and permafrost table. This interface is the zone of high concentration of organic matter and other compounds, including pollutants. The detailed physico-chemical studies will allow determining the fate of this matter in case of permafrost thawing due to climate change or anthropogenic impact. Soils will be linked with vegetation and changes in vegetation by linking various geospatial data layers to improve our knowledge and the distribution of soils and their environmental linkages