Initial data on biological activity of taiga-steppe soils in the lower reaches of the Kolyma River.

Microbiological and enzyme activities of extrazonal taiga-steppe soils in the lower reaches of the Kolyma River have been studied for the first time. Contrary to north-taiga cryometamorphic soils, predominating in the area, microbial cenoses under herb-sedge petrophytic and grass-sagebrush-herb thermophytic steppes are characterized by features typical for arid soils. The saturation of the soil profile with microorganisms is greater, and the development of actinomycetes is more intensive. The enzyme complex is characterized by high activity of dehydrogenases.

[The possible contribution of late pleistocene biota to biodiversity in present permafrost zone]. / O vozmozhnosti uchastiia pozdnepleistotsenovoi bioty v formirovanii bioraznoobraziia sovremennoi kriolitozony.

During the last decade a wide range of biological objects, which have preserved their viability for tens and hundreds of thousands of years, was found in the samples of permafrost sediments from North-East Eurasia. Among them are bacteria, fungi, algae, moss spores, seeds of higher plants, protists. Along with physiological mechanisms of cryoconservation and constant low temperature of great importance for long-term preservation of biological objects in permafrost layers are ways of burying the organisms and conditions that prevail before the transition of sediments to the permafrost state. The analysis of viability showed by preserved biological objects gives reasons to suppose that some representatives of Pleistocene biota buried in permafrost thickness may contribute to the biodiversity of present cryolite zone.