Resource characteristics of post-agrogenic chernozems in multiple-aged fallow lands of the Belgorod Region

Abstract

As a result of anthropogenic degradation, chernozems often lose their ability to provide an economically acceptable crop and, therefore, are removed from use, passing into a state of fallow. In this state, a certain restoration of the resource characteristics of chernozems is possible, but this process should be investigated using an extensive empirical base. The purpose of this work was the accumulation and primary analysis of data on the natural reproduction of forest-steppe chernozems. The authors have studied the structure and properties of regenerative (post-agrogenic) soils of abandoned arable land in the Belgorod Region which were taken out of use due to severe erosion degradation. For comparison, we have examined the arable soils located in the same agricultural landscapes. Depending on the abandoning age, the soils are characterized by different degrees of recovery in terms of humus horizon’s morphological structure and agrochemical properties. The most obvious regenerative feature of bedding rocks is the thickness of a newly formed humus horizon. For 30 years of recovery, it is 12 – 14 cm and can reach 18 cm in the 80-year-old fallow soils. Post-agrogenic soils demonstrate an accumulation of carbon and nitrogen as well as restoration of soil absorbing complex. The soil organic matter in the recent fallow lands is characterized by a narrower C/N ratio as compared to the middle-aged fallow soils. As compared to arable soils, post-agrogenic soils have less acidic solutions reaction. An intensity degree of progressive changes in post-agrogenic soils tends to decrease with age, which is an indicator of a slowdown in their recovery.