Динаміка ґрунтово-гідрологічних констант чорнозему типового різного використання

Abstract

Досліджено динаміку гігроскопічної вологи, максимальної гігроскопічності та вологості стійкого в’янення рослин чорнозему типового на лесовидному суглинку південо-східного Лісостепу Харківської області під перелогом, ріллею та лісосмугою. Установлено, що ґрунтово-гідрологічні константи, що згадуються, мають і профільну динаміку, і залежність від використання чорнозему.

Исследовалась динамика гигроскопической влаги, максимальной гигроскопичности и влажности устойчивого увядания растений чернозема типичного на лессовидном суглинке южно-восточной Лесостепи Харьковской области под залежью, пашнею и лесополосою. Установлено, что почвенно-гидрологические константы имеют как профильную динамику, так и зависимость от использования чернозема

Soil-hydrological constants provide an opportunity to assess the direction of the transformation of the soil mass, to develop a strategy for preventing or countering undesirable changes. Among the soil-hydrological constants, the maximum hygroscopicity, the soil moisture of persistent wilting of plants occupy the current position. Their value depends on the content of humus, the composition of exchange absorbed cations, the mineralogical and granulometric composition of the soil. The dynamics of hygroscopic moisture, maximum hygroscopicity and humidity of the stable wilting of plants at chernozem typical at loess-like loam of the South-East Forest-steppe of the Kharkov region under the deposit, arable land, and wooded belt was investigated. Samples were taken from three variants of the study on the genetic horizons of the soil profile. Hygroscopic humidity was determined using a gravimetric method. Maximum hygroscopicity – by saturating the soil with water at a relative humidity of at least 94 % in desiccators with 10 % H2SO4. The moisture content of persistent wilting was determined by the calculation method (1.5 MH). With the subsequent use of chernozem, a gradual decrease in hygroscopic moisture along the profile should be noted. A arable chernozem has significantly larger characteristics in the upper part of the profile to a depth of 58 cm. The near-surface soil layer of 0-10 cm of chernozem typical under the forest belt behind hygroscopic moisture indexes had a significantly larger amount of hygroscopic moisture – 5.19 %. Deeper, as in previous versions, there is a clear differentiation of this indicator beyond the genetic horizons with a decrease with depth. In the typical chernozem under the deposit, the maximum hygroscopicity varied within 6.70-7.80 %. The maximum value was found in the 0-10 cm layer. The typical chernozem in arable land had large indicators of the soil hydrological constant, which is described. Here, two maximum peaks of the indices were revealed – at a depth of 0-10 cm and 20-30 cm. The typical chernozem under the forest belt had an average maximum hygroscopicity index in the humus-accumulative horizon. The intermittent type of use of typical chernozem resulted in a relatively lower moisture index of persistent wilting of plants on average along the profile. Long-acting use of chernozem typical for field cropping led to a shift in the maximum peak of wilting moisture from the near-surface layer of soil to a layer 20-30 cm deep. The typical chernozem, that was used under the forest belt had a high humidity of persistent wilt in the upper ten-centimeter layer of soil – 13.32 % compared with other options. The hygroscopic and maximum hygroscopic moisture capacity of the typical chernozem depended on the depth and use of the soil. These indicators decreased in all options with depth increase. Their maximum levels were in the soil under the forest belt and arable land. The level of maximum hygroscopicity is more hygroscopic moisture capacity on average by 2-3 %. The moisture content of persistent wilting plants fluctuated within 10.04-13.32 % and repeated the tendency of maximum hygroscopicity