I.F. Medvedev, N.G. Levitskaya, I.I. Demakina, M.N. Lubimova
Agricultural Research Institute of South-East Region, ul. Tulaikova, 7, Saratov, 410010, Russian Federation
Summary. The article presents the results of monitoring indicators of the ecological state of soils in stationary experiments of the Institute and blocks of soil monitoring in Saratov region. The research focused on the assessment of natural and anthropogenic transformations of ecological condition of chernozems in the Volga region and their impact on the productivity of ecosystems. Among the negative factors of anthropogenic transformation of the ecological condition of chernozems in the Volga region there are the processes of erosion, dehumification, acidification, etc. Annual losses of humus due to erosion in 1980 were from 4.5 to 5.0 t/ha, and under modern conditions against the background of low-intensity of sheet erosion–up to 1.5 t/ha. The thickness of humus horizon varies from 34 to 64 cm, the reserves of humus in the soil profile ranged from 179 to 437 t/ha, the content of mineral nitrogen–from 23.8 to 48.6 mg/kg, available phosphorus–from 12.9 to 17.6 mg/kg, exchange potassium–from 179 to 289 mg/kg. Soil profiles under field crop rotations and fallows, compared to virgin lands, lost on the average over five units of monitoring, respectively 54 t/ha (15.6%) and 35 t/ha (10,1%) of humus reserves. In eroded chernozems the humus horizon decreases by 20-28%, the availability of mineral nitrogen–1.2-1.6 times. The highest biological productivity of cenosis was observed in leached chernozem under conditions of much precipitation. The modern resource potential of chernozem soils of the Volga region is characterized by changing conditions of moisture provision, the direction of soil-forming processes, medium and low humus content in the soil profile with a tendency to its further decrease, the average availability of mineral nitrogen and sufficiently high supply of available phosphorus and exchangeable potassium.
Keywords: climate change, precipitation, water erosion, relief, humus, mineral nitrogen, available phosphorus, exchange potassium, biocenosis, productivity.
Author Details: I.F. Medvedev, D. Sc. (Agr.), head of department (e-mail: Этот адрес электронной почты защищён от спам-ботов. У вас должен быть включен JavaScript для просмотра.); N.G. Levitskaya, Cand. Sc. (Agr.), head of laboratory; I.I. Demakina, Cand. Sc. (Agr.), research fellow; M.N. Lubimova, Cand. Sc. (Agr.), senior research fellow.
For citation: Medvedev I.F., Levitskaya N.G., Demakina I.I., Lubimova M.N. Environmental Assessment of the Modern Resource Potential of Chernozem Soils of the Volga Region. Dostizheniya nauki i tekhniki APK. 2015. V.30. No 1. Pp. 14-17 (In Russ.).