Recent developments

 
Glacic Histosol at Labytnangi, Western Siberia (photo Galina Mazhitova)

Recent developments

WRB Trans-Ural Polar Tour

In the framework of testing the Cryosol criteria in the World Reference Base for Soil Resources (WRB) and prior to its upcoming Revised Edition in 2006, the Institute of Biology of the Russian Academy of Sciences at Syktyvkar organized from 26 to 31 of July 2004 a tour to the tundra of North-eastern European Russia, the Polar Ural Mountains and North-western Siberia. Three days were spent in the Vorkuta region and two days in Labytnangi.

The Syktyvkar team headed by Galina Mazhitova and Elena Leptava very well organized the tour. A comprehensive field tour guide had been prepared with information on the geographical, climatological and geological setting of the region, full profile descriptions accompanied by analytical data according to WRB standards, and mineralogical and micromorphological analysis. Profile pits were well prepared, which is quite difficult in view of the environmental conditions.

The group comprised 25 participants from Austria, Belgium, Canada, Germany, Hungary, Italy, Latvia, Netherlands, Poland, Russia, South Africa and the USA, most of them active members of the WRB working group. Weather conditions were fine throughout the tour, with temperatures between 20 and 25 degrees C, wind (which kept the mosquitoes away) and clear skies (which permitted extensive photographing, especially from the air).

The soils studied during the tour classified as Histosols (Glacic, Turbic), Cryosols (Turbic), Leptosols, Luvisols and Cambisols. The classification of Cryosols was generally satisfactory, but a need was registered to adapt the definition of Cryosols to include soils with permafrost between 1 and 2m depth, in which cryoturbation affects the surface. Another difficulty encountered was to establish the prevalence of either gleyic or stagnic conditions; due to cryoturbation, gleyic or stagnic colour patterns cannot be separated. It has therefore been decided to delete the two qualifiers from the list, and to replace them with “reductaquic” (indicating reductive wet conditions, giving a positive reaction with alpha,alpha dipyridyl) and “oxyaquic” (indicating oxidative wet conditions, no reaction with alpha,alpha, dipyridyl). Furthermore, the gypsic qualifier has been dropped and replaced by “gypsiric”, to cater for Cryosols on gypsum deposits. Similarly, a “calcaric” qualifier has been added to cover the Cryosols over calcareous deposits.

It has been discussed extensively if the andic, vitric and spodic qualifiers should be retained, or that soils showing these features should belong to the Major Reference Groups of Andosols and Podzols, respectively. So far, no Andosols with permafrost within 1m have been found (see also the new book on Cryosols, edited by John Kimble), whereas cryoturbated Podzols are quite extensive in Central Siberia, linking up geographically with the Podzol belt. A decision on this has been postponed until sufficient data are collected to justify a final choice.

The classification of boreal Histosols worked fine, providing enough information to be able to interpret their properties and required management. No adjustments will be needed.

Discussion on Cryosols – Leptosols focussed on whether the present sequence of the Key (Cryosols keying out before the Leptosols) is practical. A similar discussion took place in 1996 with the introduction of the Cryosols in the present Key. On advice of the Canadians, Leptosols then were placed after the Cryosols, as a compromise to their wish to have Cryosols key out first, as is done in Soil Taxonomy with the Gelisols. However, such placement requires surveyors and researchers to establish the occurrence of permafrost within 1m in, for example, mountain scree deposits, which is quite cumbersome and not very useful. It is therefore proposed to place the Cryosols after the Leptosols in the new Key, and not to use “cryic”, “turbic” or “gelic” qualifiers in the Leptosols.

Both Cambisols and Luvisols need a “turbic” qualifier to indicate active cryoturbation without the presence of permafrost within 2m. A similar observation was made during the Iceland tour in relation to the Andosols.

Besides classification issues, we were also introduced to engineering aspects of Cryosols. One morning we were guided around Vorkuta to look at various options for building constructions, hot water supply and appliances to maintain permanently frozen ground. We learned about the instability of “warm” permafrost (temperature of about -0.5 degrees C) and the stability of “cold” permafrost (temperature less than    -1 degrees C), and the high variability in depth of the permafrost that interferes with the construction activities. We saw various examples of the necessary non-insulated foundations, and the results of ill-constructed houses and apartment flats. Various devices are used to permanently keep the ground frozen; most refrigeration runs on methane and propane gas.

WRB above the Arctic Circle (photo Stanislaw Brozek)

WRB above the Arctic Circle (photo Stanislaw Brozek)