DYNAMICS OF HUMUS RESERVES AND FORECAST OF CARBON-INVESTING POTENTIAL OF ZONAL SOILS OF THE REPUBLIC OF TATARSTAN

The article analyzes the results of statistical processing of morphometric and agrochemical indicators of zonal soils of the Republic of Tatarstan based on the accumulated information of large-scale soil studies. The boundaries of genetic horizons are examined, the content of humus and its reserves within the limits of heavy loamy and clay varieties of arable soil subtypes is estimated. Arithmetic averages allow us to generalize the humus content in soils. So, in the series of sod-podzolic soils – light gray forest-gray forest – dark gray forest-podzolic chernozems – leached chernozems-typical soils in a layer of 0-30 cm on average contains 2,20; 2,58; 3,76; 4,76; 6,8; 7,6; 7,2 % humus. The observed patterns of humus accumulation in soils are also preserved in the distribution of its reserves – 85; 97; 140; 162; 233; 257; 240 tons per he-1. It is proposed to characterize the general population along the boundaries of typical values that fit into the 50% confidence interval to assess the overall range of spatial variability of humus indicators. The upper limit of the typicity will correspond to the greatest accumulation of humus with a combination of local features of soil formation factors and can serve as a guide for predicting carbon sequestration in the soils of this region. Accordingly, the carbon-sequestering potential of sod-podzolic soil and typical chernozem is-20 tons per he-1, light gray forest soil-22 tons per he-1, gray forest soil and leached chernozem-27 tons per he-1, the highest values in dark gray forest soil are more than 30 tons per he-1