Alexandra Golyeva

Biomorphic analysis as a part of soil morphological investigations

Abstract Biomorphic analysis is the microscopic investigation of plant tissue, detritus, phytoliths, pollen and other remains of biota for the reconstruction of ancient pedogenic conditions and the evolution of soils. Each biomorph is associated with certain types of landscape, and provides information on conditions of soil development and on landscape evolution. Every stage of soil development forms its own biomorph profile, and profiles of different stages can be distinguished. They indicate the main vegetation changes during the Holocene. Human impacts such as grazing, tillage and tree felling also exert a considerable influence on the qualitative and quantitative distribution of biomorphs through the profile. As examples, samples were studied from soil profiles representing different climatic subzones of the Russian Plain. The results show that biomorphic analyses can provide information that is otherwise unobtainable and can elucidate some controversial questions of soil genesis and cultural changes.

Buried paleosols in balks of Kalmykiya as a record of late Holocene nature and society interaction

Abstract Modern and buried soils under valley sediments have been compared on the Southern Russian Plain (Kalmykiya) in the arid zone. The buried soil contains more humus and less carbonates, and pH values are lower. The humus content in this soil is comparable with that of modern Haplic Kastanozems and Gleyic Phaeozems. The comparison of differences in properties of buried soil at specific times and historical data on cultures’ functioning in these periods has allowed us to reveal the interrelation of nature and society processes development in South Kalmykia since the middle Holocene. Three stages of landscape development are recognized: (1) stable stage, at least 3000 years long (from the 2nd millennium BC until the 1st millennium AD), characterized by the formation of meadow-steppe soils; (2) dynamic stage, likely short, when deposits were accumulated, and soils were buried; and (3) modern stable stage, at least 500 years long (up to the present time), characterized by the formation of meadow-saline soils (Molli-Endogleyic Solonetz) on deposits in valleys. A strong ecological crisis was evident in the territory of modern Kalmykia about 1000 years ago, resulting from the collapse of the Khazar state. As a result, meadow-steppe soils were buried, and Saline Molli-Endogleyic soils were formed.