Assessment of Fire Effects on Surface Plants Cover and Some of the soil characteristics in the rangeland of Lorestan province (Case Study: North East of County - Garin Mountain)

The aim of this study was to assess the regional effects of fire on the surface cover and soil characteristics of mountainous rangelands of Delfan County, Lorestan province, Iran. which seems has significant effect on vegetation characteristics on the study area. Four fire affected sites were selected for sampling and a close area without fire was considered as control. Sampling was carried out using random systematic method and the size of plots was determined using the minimal area framework. The number of plots was determined using statistical method. Totally, the data of eight sites including four fire affected sites and four control sites were measured during four consecutive years in early July of each year after fire. In each site, four transects of 50m length were selected in the direction of slope as well as perpendicular to the slope and five plots were established along each transect. Soils samples from the beginning, middle and end of each transect were taken from a depth of 0-30 cm. Independent t-test was used to compare the mean of the factors in two control and fire zones, and one-way ANOVA and Duncan test were used to compare the years. The results showed that fire caused a significant increase in forage production, cover percentage, perennial grasses density and forbes and percentage of litter cover. Also, the density and percentage of shrub species and bare soil cover decreased significantly. The fire caused an increase in organic matter, electrical conductivity, nitrogen, potassium, phosphorus and soil texture.