Академическое издательство «Гео»

Keywords: peat deposit, Dagestan, Holocene, age-depth model, peat composition, accumulation rate.


Swamps of East Caucasus as high resolution archives of paleogeographical information

N.E. Ryabogina*, I.A. Idrisov**, A.V. Borisov***, A.S. Afonin*, E.P. Zazovskaya****

*Tyumen Scientific Center, Siberian Branch, Russian Academy of Sciences,
625003, Tyumen, POB 2774, Russia, nataly.ryabogina@gmail.com, hawk_lex@list.ru
**Institute of Geology, Dagestan Scientific Center, Russian Academy of Sciences,
367010, Makhachkala, ul. Yaragskogo, 75, Russia, idris_gun@mail.ru
***Institute of Physicochemical and Biological Problems of Soil Science, Russian Academy of Sciences, 142290, Pushchino, ul. Institutskaya, 2, Russia, a.v.borisovv@gmail.com
****Institute of Geography, Russian Academy of Sciences,
119017, Moscow, Staromonetnyi per., 29, Russia, zaszovsk@gmail.com

We examine the regional conditions for swamp formation in different geomorphological settings and characteristics of their emergence, water feed and functioning in the middle mountain zone of Dagestan. Comprehensive investigations used, as the basis, the largest area of swamps located at the transition from the slope of the Arzhuta ridge to the Khunzakh plateau at altitudes of about 1860 m. We investigated the 1.5 m profile of the Shotota lowland swamp, estimated its age using 14 radiocarbon datings and developed the age-depth model. It is established that the grass marsh was continuously evolving in geomorphologically stable conditions for more than 7400 years. It is pointed out that according to the accumulation rate in the peat layer of the profile (averaging 1 cm per 62 years), the Shotota peat deposits may well become the first high resolution long-period natural archives of the northeastern part of Caucasus. It is determined that the development of this peat deposit and underlying sediments encompasses most of the Holocene, including periods of intense agricultural land use of the mountain zone of Dagestan starting in the Neolithic. Data obtained for changes in the peat composition, accumulation rate, degree of decomposition and ash content revealed large phases of change in the region’s moisture content. It is emphasized that a further study of the paleoecological records in the Shotota profile will permit a detailed reconstruction of the Holocene landscape-climatic conditions to provide fundamentally new information on the evolution of nature and development of the territory of East Caucasus by humans.

Keywords: peat deposit, Dagestan, Holocene, age-depth model, peat composition, accumulation rate.

DOI: 10.21782/GiPR0206-1619-2019-2(85-94)