Soils of xerophytic meadows of the Middle Podesen’ya: on the issues of accumulation of organic substances and biochemical activity

Abstract

Relevance. Natural meadow communities, belonging to the dry meadows group, in the conditions of a decrease in floodplain of the leading water artery in the Bryansk region — the Desna River are characterized by significant changes in the mode of economic use. However, a significant part of dry meadows is used as pasture lands, so the regime of intensive exploitation of these lands significantly changes the ecological regimes of phytocenoses, reducing the carbon-depositing functions. For xerophytic (dry) meadows of natural origin, the establishment of soil carbon reserves, the identification of biochemical and microbiological activity is especially important in the light of the low stability of these communities under pasture load and wide distribution throughout the territory of the Middle Podesen’ya.Methods. The research provided for field route studies and in-house data processing using the methods of trial sites, the method of ecological and floral classification, the method of ecological scales (according to G. Ellenberg), ecological and chemical methods — determination of organic carbon, the weight method, biochemical and microbiological methods for the study of the biocompatible body.Results. For the soils of xerophytic (dry) meadows, for the first time, carbon-absorbing capacity, enzymatic activity for urease, catalase, cellulase, depending on the phytocenotic complex, has been established for the Middle Podesen’ya. A positive strong correlation has been established with organic carbon and average monthly precipitation in June, July and August. Over a two-year observation period, the amount of total organic carbon in the soil changed in a number of associations communities: Festuco ovinae-Koelerium delavignei > control > Agrimonio eupatoriae-Poetum angustifoliae > Caro carvi-Deschampsietum > Anthoxantho-Agrostietum tenuis > Hieracio pilosellae-Agrostietum tenuis > Koelerio delavignei-Festucetum rubrae > Anthyllidi-Trifolietum montani > Polygalo vulgaris-Anthoxanthoetum.