Fire Impacts on Forest Ecosystem: With a Focus on the Resilience of Tree Species and Dramatic Change in Insect Populations

The research data was collected from forests located at Haibat Sultan Mountain in Koya district for three years from 2014 to 2017. At the sampling location, fire outbreaks occur many times a year. This study aims to determine the environmental impacts of forest fire on vegetation and insects. This results in the identification of the most fire-resistant trees and the impact of burning on the environment. In the Haibat Sultan Mountain forest, four types of tree species are distinguished which are Pine, Cupressus, Pistachio and Oak, their contribution to cover the area is 63%, 19%, 15% and 3% respectively. Oak is the only native tree of the forest and one of the most resistant species, 93 percent of which can survive, but the other species Cupressus, Pine and Pistachio are introduced with different level of vulnerabilities, with 75%, 60% and 41% of combustion rates, respectively. Forest fire has a significant negative impact on the population of Thaumetopoea solitaria Freyer and Schistocerca gregaria, both of which are the main insects of the forest. The average of the number of egg masses of Thaumetopoea solitaria and nymph and adult of Schistocerca gregaria before the fire is (18.8 masses and 4.1 nymphs and adults), but the average declined dramatically to (3.3 masses and 0.9 nymphs and adults) during the fire season. In the post-fire season, the average is increased significantly (6.3 masses and 1.9 nymphs and adults).