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The paper presents an assessment of the rates of erosion and sedimentation in hollows of the Temeva Rechka small dry valley catchment, dominated by forest-steppe gray forest soils (Luvic Retic Greyzemic Phaeozems), over the past 55–60 years with the use of the radiocesium technique. This catchment is located in the Myosha River basin (Republic of Tatarstan, European Russia). The hollows have been grouped by the catchment's slope aspects, hollow length, hollow bottom gradient, and shape of the thalweg profile of the hollow bottoms; origin and age, as well as by the specifics of erosion/sedimentation processes. Short agrogenic hollows with a small catchment area on relatively steep western slopes of the Temeva Rechka small dry valley, probably formed after human deforestation, have been identified. The shape of their catchments contributes to the formation of surface runoff, sufficient for the erosion of a significant part of their bottoms at a rate of about 2–4 t/ha per year. Older, polygenetic, and relatively long hollows with a slightly sloping bottom and larger catchments serve as sediment transit zones between plowed areas and the Temeva Rechka small dry valley bottom. They are characterized by alternating areas of soil erosion and sediment accumulation. The average rate of soil erosion in these landforms is 0.8 t/ha per year. In some hollows, when several small tributaries (smaller hollows) flow into their lower parts, soil erosion loss increases to 3 t/ha per year. The average soil erosion loss is 6 t/ha per year on short slopes of the hollows; in their upper parts, it can reach 11 t/ha per year. There is a general decrease in the rates of soil erosion and accumulation of eroded material in recent decades due to changes in climate and land use. [ABSTRACT FROM AUTHOR]

To assess the state of soil and plant resources of the territory of several river catchments, the indicator of soil-productive potential (fraction of absorbed photosynthetically active radiation based on ground and remote data, FAPAR), as well as indicators of the phytomass reserve, data on phytocenosis production and land use, and leaf area index (LAI) were used. It is shown that ecosystems of river basins located in different climatic zones react ambiguously to climate change. The data obtained make it possible to forecast the dynamics of soil-productive potential in the conditions of changes in climatic characteristics, such as temperature and precipitation. It is shown that the productive potential continues to grow with time only in those areas, where the amount of biologically active temperatures is a limiting factor, i.e., in river basins within the zone of mixed forests. It is found that in river basins with limited precipitation, the temperature increase will lead to a decrease in the soil productive potential. [ABSTRACT FROM AUTHOR]