SALINATION OF POSTPIROGENIC SOILS OF UKRAINIAN ROZTOCHYA

Abstract

Introduction. One of the most dangerous phenomena of fires in natural ecological systems is the physicochemical and structural changes of soils due to temperature (pyrogenic) factor. Such types of fire, except for the instantaneous destruction of the biocenosis, have a secondary impact on all components of the environment for many years - ecosystem restoration is slow or non-existent, riverbeds change, new ecotopes formed, physicochemical properties of soil change irreversibly. Pyrogenic degradation of edaphotopes leads to their slow recovery. Many scientific works are devoted to this issue in Ukraine and abroad. All of them can be classified into the following groups: pyrogenic degradation ofpeatlands, physicochemical properties of post-pyrogenic soils, pyrogenic succession. Postpyrogenic soils require detailed research depending on specific natural and climatic conditions, which, in addition to temperature, are crucial in the processes of ecological renaturalization of vegetation.Aim and methods. The work aims to establish the relationship between the post-pyrogenic factor and soil salinity overtime for the Ukrainian Roztochya. For measuring the flame temperature used fluke thermal imager. Soil moisture was determined using a moisture meter "MG-44". Soil acidity was determined using a contact device "KS-300V". Modelling the acidity distribution into the genetic horizons was performed using a demo version of Surfer software. Statistical values are processed using MS Excel. In the research used: statistical, chemical, pedologic, phytocenotic methods.Results and discussion. Due to the high salinity of forest fires, we determined the content of chlorides, sulfates, phosphates in the samples. We found that the highest content of chlorides and sulfates is inherent in the investigated area №4, namely: in the horizon of 0-5 cm chloride content is 432.1 mg/kg, in 5-10 cm – chloride content is 267.1 mg/kg, in 10-20 cm – chlorides content is 142.7 mg/kg; in the horizon of 0-5 cm sulfate content is 235.7 mg/kg, in 5-10 cm – sulfate content is 160.3 mg/kg, in 10-20 cm – sulfate content is 131.7 mg/kg. The extremely salt content in the area with the model fire indicates significant salinization due to the ground fire. The level of chlorides and sulfates is much lower than in other areas, depending on the age of ground fires occurrence, which indicates the natural restoration of edaphotopes and alignment of salinity to background values.Conclusions. As a result of a research of the salinity of post-pyrogenic soils of the Ukrainian Roztochya, we found that the restoration of edaphic indicators of the loam depends on the age of the ground fires occurrence. For researching of acidity and salinity of soils accepted the range of occurrence of grassland forest fires four years ago We found that in the investigated areas exposed to fire long ago, the indicators of acidity and salinity correspond to the background values and are much lower than the same values for the model fire area.