SUITMA 2005 Cairo - The buried soils of antique Tanais City, Russia
SUITMA 2005 Cairo
| This abstract is about one of the papers of the Historical sites theme of the SUITMA 2005 symposium. |
| Olga Bezuglova,i | Igor Morozov.i |
- i - Department of Soil Science and Agrochemistry, Rostov State University, Rostov, Russia.
Tourists get acquainted with the ruins of antique city Tanais, destroyed at the III century AD, on the territory of the archeological museum with the same name. This museum is located one hour drive from Rostov-on-Don, the southern part of Russia. Researchers of our department started soil investigations in the complicity with scientists of the Archeological Laboratory of the Rostov State University in 2000. Soil profiles were pitted in archeological cuts. According to the archeological data, the age of buried soils, which were found out on depth of 4.5 meters approximately, is more than 2300 years.
Humus contents, рН, carbonates, mobile forms of iron (FeO) and phosphates (P2O5) and exchangeable potassium were analyzed. Additionally, the bulk density, density of soil particles, structural condition, texture, hardness and content of maximal hygroscopic water were investigated.
The investigation has shown that the buried soils can be diagnosed as the meadow chernozemic ones, according to their morphological, chemical and physical properties. It is very interesting fact because the current soil cover is presented by calcareous ordinary chernozems. The change of the soil cover structure deals with the significant falling down of ground-water table. At the present time ground waters are disclosed behind 18 meters due to the transgression of the Azov Sea. The humus content in top horizons of modern meadow chernozems reaches 5-5.5 % on average. In the same horizons of buried soils its quantity is only 1.8 — 2.9 %. To sum it up at the early iron epoch the humus content in the top horizons of these soils was approximately 5 — 5.5 %, then its amount in buried soils is about 30 — 35 % from initial. As known, the decrease of the humus content in buried soils is the universal phenomenon. The level of dehumification depends first of all on the age of a burial place and reaches 50-70 %. The distinction for the depth of the humus layer has been established. The depth of the layers in modern soils is changing from 87 up to 100 cm, but in our case the depth of A+B is reaching only 66 — 85 cm. In modern soils with the same genesis the contents of mobile iron is about 6 %, but in our case its content is only 3.5 — 4 %. According to archeological data, it is known that in the history оf the antique Tanais large fires were occurred from time to time. Probably, the high contents of potassium deals with an impurity of ashes, found as inclusions in all archeological profiles.
The analysis of physical properties of meadow chernozems has shown, that these soils can be classified, according to their texture, as a silty clay loam. Our investigation has shown that the buried soil has been well kept, despite of the significant period of burying. This soil can be classified as meadow chernozem, because it has the most significant attributes of meadow process, though it was isolated from intensive influence of the external factors under cultural layers with the depth about 4-4.5 m during long period of time (more than 2000 years).
