The effect of fire on the quantitative and qualitative characteristics of alpaine rangelands vegetation (case study: Lorestan research site)

Fire is the fastest cause of extensive changes in vegetation. The purpose of this research is to examine some of these changes. SO, after determining key area of four 200m transects and a distance of 100 m from each other, 10 plots 1m2 fixed on each of them, formed sample units in each field. This site burned in 2011 and 2013, in 2018 and 2019, random-systematic statistical collection was carried out in it. Results showed, in fire treatment the dominance of production and cover is with invader plants. Production of this class 52.05 and 209.1gr/m2 has been preserved in burnt area compared to control. Also, annual grasses have significant average difference in terms of production and canopy compared to other species. However, annual forbs had 1.5 times more production in fire than control. Although the amount of production in burnt area is more than control but, it doesnt mean an increase in the amount of allowable forage. The plant type in the burned fundamental change compared to the control by replacing annuals instead of permanent species. As result production, density and canopy cover of different palatability classes and growing forms also found fundamental changes. Fire is cause of changing in rangeland condition from excellent to average, the trend is positive in both treatments. The management of burnt fields is very specialized, and according to the existing conditions, it is strongly not recommended to create a fire either intentionally or accidentally in this area is vegetation zone form of Iran.