Earth’s Cryosphere, 2009, Vol. XIII, No. 2, p. 44-54

HUMUS-FRACTIONAL TYPE CONTENT OF SOILS OF THE EURASIAN TUNDRA ZONE

L.A. Fominykh, B.N. Zolotareva, A.L. Kholodov, L.T. Shirshova

Institute of Physicochemical and Biological Problems of Soil Science RAS, 142290, Moscow region, Pushchino, Institutskaya str., 2, Russia, azol@issp.serpukhov.su

The humate-fulvat type of humus of modal loam soils in temperate and ultracontinental regions of tundra zone plains has been determined. The 1st and the 3rd fractions of humic substances predominate in humus composition. The differentiation of humic profiles is regulated by the content and distribution of silt and thin dust granulometric particles. The correlation between the humus content and the composition has been established.

Key words: Humus, humic substances, type of humus, fraction composition, cryolithozone.

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