This study investigates the effects of agricultural exploitation of soils of the north-western Crimea, the active and large-scale cultivation of which began with the Greek colonization of the area. In order to compare soils using a wide spectrum of physical and chemical properties, the studied objects (virgin land, post-antique idle land, continually plowed land, modern-day plowed land, idle land of the modern era) have been grouped into a chronosequence. This makes it possible to apply the method of factor sequences of agrogenic transformations in soils, which takes into account different periods of human activities. The other factors involved in soil formation are considered to be relatively invariable. From the mass of physiochemical properties of these soils that have endured long-term agricultural stress, the most informative indicators of agrogenesis have been identified. The authors propose a procedure for calculating an integral agrophysical soil indicator based on five parameters that can be used to determine the soil structure and cloddiness as well as water-stability, the amount of waterstable aggregates and their mean mass-weighted diameter. Based on the estimates of their agrophysical state, the following sequence has been determined for the soils studied: Post-antique idle land b virgin land b idle land of the modern era b continuously plowed land b modern-day plowed land. It has been established that the previous practices of land use favorably affect the agrophysical properties of soils. The loss of organic carbon in continually plowed land is 51%, while in modern-day plowed and idle lands it amounts to 39% and 27-32% respectively. The reproduction of soil organic matter (SOM) and its quality, particularly of its labile content, which is responsible for the agrophysical properties of a plow horizon, is central to soil fertility management for sustainable agriculture. One observed effect of long-term agrogenic stresses in plowed horizons of Chernozems is a decrease in microelements such as Co, Ni, Mn, Cu, Zn, Pb, as well as phosphorus and potassium. It is estimated that the micronutrient content of plowed land is 5-6% lower than that of virgin soils. Even after 2280 years of renaturation, soils of post-antique idle lands preserve in their pedomemory the signs of agrogenesis. In terms of soil quality, the overall agrogenic transformation of soils cultivated during the recent period (the last 150-165 years) is 15% lower than that of the continually plowed lands. The fallowing regime provides conditions that allow soils to regenerate within a few decades. The use of renaturation effects that mimic the fallowing regime opens up new possibilities for resource-saving sustainable agriculture. This study, therefore, shows the informative potential of soils that have continuously, or with restorative periods, been subjected to long-term agrogenic impacts under different practices of land use. It also considers how this information may be actively employed to comprehend the long-term transformations of the ...

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Abstract-Fallow lands in ancient agricultural areas of Northwestern Crimea which had experienced repeated phases of agricultural activity at different time periods (the Late Bronze Age, antiquity, and the last 150−200 years) have been studied. Differences in biogeochemical fluxes for virgin and fallow soils are analyzed from the chemical elements determining the composition of secondary clay minerals. The most informative and evolutionarily significant biogeochemical indicators of relict agricultural loads and duration of fallow periods are specified.

The quantitative and qualitative depletion of water resources (both surface and groundwater) is closely related to the need to protect soils against degradation, rationalization of land use, and regulation of surface water runoff within the watershed area. Belgorod Oblast (27,100 km2), one of the administrative regions of European Russia, was chosen as the study area. It is characterized by a high activity of soil erosion (the share of eroded soils is about 48% of the total area of arable land). The development phase of the River Basin Environmental Management Projects (217 river basins from the fourth to seventh order) allowed for the proceeding of the development of an integrated monitoring system for river systems and river basin systems. The methods used to establish a geoecological network for regional monitoring include the selection and application of GIS techniques to quantify the main indicators of ecological state and predisposition of river basins to soil erosion (the share of cropland and forestland, the share of the south-oriented slopes, soil erodibility, Slope Length and Steepness (LS) factor, erosion index of precipitation, and the river network density) and the method of a hierarchical classification of cluster analysis for the grouping of river basins. An approach considering the typology of river basins is also used to expand the regional network of hydrological gauging stations to rationalize the national hydrological monitoring network. By establishing 16 additional gauging stations on rivers from the fourth to seventh order, this approach allows for an increase in the area of hydro-agroecological monitoring by 1.26 times (i.e., up to 77.5% of the total area of Belgorod Oblast). Some integrated indicators of agroecological (on the watershed surface) and hydroecological (in river water flow) monitoring are proposed to improve basin environmental management projects. Six-year monitoring showed the effectiveness of water quality control measures on an example of a decrease in the concentrations of five major pollutants in river waters.

A new type o f livestock enclosure from the Late Bronze Age has been discovered. Stone walls outline a pair o f circular or oval areas that may be up to 50 m in diameter. The stone walls are invisible at the surface; they were discovered in northwestern Crimea and only w ith the aid o f remote sensing and geophysical surveys. In the period 2 0 0 7-2 0 2 0 , over tw o dozen o f these structures were found; none has ever been noted before. The locations o f these sites were firs t suggested in satellite imagery, often as areas w ith unusually green vegetation. Then, large-area magnetic surveys delineated the buried stone enclosures, fo r there was a good contrast between the non-magnetic limestone walls and the rather magnetic soil. The features can be identified by the unique pattern o f the walls: An almost-complete circular arc that is connected to a full circle or oval. The soil w ithin the features has a high level o f urease enzyme activity and a high concentration o f therm ophilic microorganisms. This suggests the composting o f animal dung and plant residues; therefore, these were corrals and the raising o f livestock was a part o f the economy. Only one o f the doubled enclosures is found at most settlements; the livestock were probably owned by all o f the inhabitants. Each settlem ent had several dwellings, and these had earthen basins whose edges were lined w ith vertical stone slabs. Several small-area excavations exposed corral walls. Magnetic measurements o f the soil and rock were the basis fo r magnetic models; the calculated anomalies agree w ith the measurements o f the magnetic maps.