Temporal and Spatial Features of Phosphatase Activity in Natural and Human-Transformed Soils

Data on phosphatase activity (PA) in soils of different natural zones, intrazonal soils, buried soils, and cultural layers in archaeological monuments of different age were summarized. The variability of PA in soil complexes was analyzed. The maximum values of PA were recorded in the upper horizon of Eutric Retisols, and minimum values were found in Haplic Calcisols of the Baer hills in the Caspian Lowland. In Solonetzes, a wider variation of PA in the A1 horizon was recorded as compared to that in Cambisols and Calcisols. Mean value of PA in the upper horizon of Solonetz was 1.5 times higher than in the upper horizon of Cambisols and Calcisols. The maximum values of PA in the profile of Solonetz were determined in the uppermost 2-cm-thick layer. The B1 horizon of Cambisols and Calcisols had a higher PA in comparison with that in the A1 horizon of these soils, whereas the B1 horizon of Solonetz had a lower PA than that in the A1 horizon. In the paleosols buried under kurgans of different age, PA was higher in paleosols buried in humid epochs than in paleosols buried in arid epochs. Cultural layers of ancient settlements had the maximum variability of PA values. In some cases, in the cultural layers with low organic matter content, the values of PA correlated with the content of phosphates. In the cultural layers with ash and charcoals, the low values of PA were recorded at high phosphate content.