Annotation

The paper presents the results of researching into the effect of drip irrigation on calcium treatment of chernozyom soils, which were used for tomato growing in high tunnels. It was established that the manner of distribution of different forms of calcium (water-soluble, exchangeable and carbonate calcium) was graded through the year. During the irrigation season in the upper soil layer the quantity of soluble calcium, exchangeable calcium and carbonate calcium is increasing. In spring the quantity of soluble calcium in the upper soil layer is decreasing due to the winter precipitation. Under the influence of drip irrigation the carbonates build up in the upper soil layer, while the soil depth is increasing the quantity of carbonates is decreasing as opposed to natural soil conditions without irrigation, where the content of carbonates is minimally in the upper soil layer and increasing together with the soil depth.