Assessment of the humus state of hortically suitable soils Northwest Caucasus

Kuban State Agrarian University, 13, St. Kalinina, Krasnodar, 350044, Russia

^* Corresponding author: kubsoil@mail.ru

Abstract

The laying of intensive industrial gardens in Russia is carried out according to special projects, which are based on complex works that begin the selection and assessment of the soil suitability of land plots. The levels of total humus and its labile forms have been established for the main horticultural soils of the Krasnodar Territory on the basis of long-term studies. The use of these criteria makes it possible to assess the degree of cultivation or degradation processes of the soil cover of each specific garden plot. Studies have shown that, in all surveyed soils of the region, the profile distribution of humus is gradually decreasing. The most informative soil layer for assessing fertility can be considered the upper 30 cm layer. The greatest quantitative and qualitative changes of organic matter occur in this layer. Different gardening zones of the region differ in the content of total humus in the main types of soils, a decrease is observed from ordinary chernozems (northern zone) to alluvial meadow soils (river valleys of the foothill zone). The humus content in the natural cenoses of Kuban chernozems reached 5.5 %, and in heavily plowed soil up to 3.5 %, a similar situation was observed in floodplain soils, these values corresponded to 4.0 % and 2.0 %. All other types of soils occupied an intermediate position in terms of humus content.