Annual dynamics of hydrothermal conditions of natural and anthropogenically transformed soils

[摘要] Soil temperature is a key factor controlling many biotic and abiotic processes in soils. It is important to perform temperature monitoring of peat and mineral soils. An atmosphere-soil monitoring system is used to study the hydrothermal regime of soil at two sites (abandoned cropland and spruce forest) with different vegetation covers, top soil structures, and moisture regimes. The observations were carried out from 1 July 2013 to 30 June 2017 in soil profiles from the surface to a depth of 320 cm. In the early 20th century, the present abandoned cropland site was occupied by spruce forest, but later it was used as cropland. The trees were cut down and the top soil was used for croplands. Now the croplands are abandoned and covered with steppe grasses. Differences in vegetation covers lead to differences in soil thermal regimes. The abandoned cropland site soil is better warmed up than the spruce forest soil. The zero isotherm at the spruce forest site reaches a depth of 120-130 cm, while at the abandoned cropland site the zero isotherm is observed deeper than 320 cm. Negative soil temperatures exist at the spruce forest site at depths from 130 to 320 and deeper reaching permafrost soil.

[发布机构] Institute of Monitoring of Climatic and Ecological Systems SB RAS, Tomsk, Russia^1;V.B.Sochava Institute of Geography SB RAS, Irkutsk, Russia^2

[效力级别] 计算机科学

[关键词] Abandoned croplands;Hydrothermal conditions;Soil monitoring;Soil temperature;Spruce forest soils;Temperature monitoring;Thermal regimes;Vegetation cover