Vegetation dynamics and soil properties following low-intensity wildfire in loblolly pine (Pinus taeda L.) planted forest in Northern Iran

Abstract

Vegetation dynamics, soil properties, and the correlation between them following a wildfire are crucial to understanding the recovery of forest (natural or planted forest) ecosystems. We compared species composition and soil properties in two burned (Br) and unburned (UBr) sites of loblolly pine (Pinus taeda L.) stand in Northern Iran. We detected 39 plant species including 22 (56.4%) species that were common in both sites, 13 (33.3%) species specifically in the Br site, and 4 (10.3%) species specifically in the UBr site. Although species abundance was significantly higher in the UBr site, species richness was significantly higher in the Br site. Species composition was significantly different (F = 16.25, P-value = 0.001) between Br and UBr sites. Rarefaction-extrapolation revealed consistently and significantly higher species diversity in Br site compared to UBr site for all three Hill numbers. Only sand (t = 2.23, P-value = 0.030), pH (t = 2.44, P-value = 0.018) and electrical coductivity (t = 2.98, P-value = 0.004) were significantly higher (P-value ≤ 0.05) in the Br site due to the demobilization of base cations in burnt vegetation. In the Br site, the wildfire did not cause any marked changes in C and N stocks.