Yangın Sıklığı Ve Vejetasyon Örtüsünün Akdeniz Vejetasyonu Dinamikleri Üzerine Etkisinin Modellenmesi
Özet
In the last century, global changes have resulted in changes in fire regimes and vegetation structure in the Mediterranean basin. In this study, long-term effects of fire frequency on vegetation dynamics were examined using a modelling approach in pine woodland and maquis shrubland landscapes. Simulation scenarios created with different functional groups involving certain life history traits and regeneration strategies on different total initial plant cover and different fire frequencies. These functional groups were determined as Pinus (seeder trees) Quercus (obligate resprouter large shrubs), Erica (facultative resprouter shrubs), Cistus (seeder shrubs) and Brachypodium (obligate resprouter herbs). We used spatially-explicit FATELAND model considering functional traits for computing the relationship between fire and vegetation dynamics. Seven fire scenarios (fire in each 5 to 80 years and no fire scenarios) and 10 total initial plant cover scenarios (from 0 % to 100 % cover of the landscape) in 3 different landscapes. Scenarios were run for 120 years in different landscapes to obtain final abundance of funstional groups.
The final abundance of Pinus was negatively affected by the fire frequecy and the presence of Quercus. Although Quercus was slightly affected from the fire frequency, this functional group dominated the vegetation in the most of the scenarios. The increase in fire frequency promoted the final abundance of Erica, Cistus and Brachypodium, however the increase in total initial plant cover affected the final abundance of these groups negatively. In the maquis shrubland landscape, similar results on final abundance were obtained with the pine woodland landscape. However, excluding Quercus from pine woodland clearly increased the final abundance of all functional groups. This study shows that the initial abundance of resprouter large shurbs is another key driver of post-fire vegetation dynamics in the Mediterranean Basin along with fire frequency.