Effects of forest fire on some soil chemical, physical and hydro-physical properties of black and Turkish pine mixed stands in Bursa-osmangazi

Soil, which is of vital importance for the functioning of ecosystems and human life and is a feeding and stopping place for plants, is one of the most important and fundamental elements among our natural resources. Factors that reduce soil quality and productivity and negatively affect the soil can often be caused by human activities, such as floods, overflows, droughts, fires, etc. It can also occur through natural processes. The relationship between fire and soil properties is quite complex. The effects of fires on soil depend on factors such as soil type, structure, and moisture content, and these interactions determine the rate of spread, severity, and consequences of fires. The sensitivity of soils to fire and post-fire recovery processes are also of great importance in maintaining environmental balance. After a fire, regeneration of soil and vegetation is critical for the sustainability of forest ecosystems. In this study, in order to determine the effect of forest fire on soil properties, disturbed and undisturbed soil samples were taken from 50 forest fire-affected areas and 50 adjacent areas where fire damage was not observed. Properties such as texture (sand, clay, silt), water-holding capacity, permeability, hydraulic conductivity, bulk density, organic matter, soil reaction (pH), electrical conductivity, dispersion, and clay ratio of the soil samples were determined, and statistical data were obtained between the two areas. Differences have been revealed. Descriptive statistical analyses (mean, highest and lowest values, standard deviation, slantness, kurtosis, etc.) of the properties of the soils subject to the research were carried out; Whether the variables showed normal distribution was evaluated with the Kolmogorov-Smirnov one-sample test. An independent sample t-test (for those with normal distribution) and Mann Whitney U test (for those with non-normal distribution) were used to compare the soil properties of burned and unburned areas. The significance check of the difference between the averages was made with the "Independent Sample T test" and the "Mann-Whitney U test". Significant differences were detected at the p<0.05 level in soil samples taken from burned and unburned areas in terms of water-holding capacity, hydraulic conductivity, bulk density, pH, EC, dispersion ratio, and organic matter. Among these properties, silt content, water holding capacity, organic matter, electrical conductivity, and clay ratio had higher values in the forest area than in the burned area.