Dry Grassland Post-fire Impacts in Biribiri State Park, Minas Gerais, Brazil

ABSTRACT This study aimed to evaluate the natural post-fire regeneration in dry grassland. We selected three sites: I and II, with occurrence of fire and III with no occurrence. Each site received one transect with 20 plots of 5 × 5m (25m 2). Diameter at ground level (DNS), total height and regrowth of all individuals with height ≥ 0.10 m and DNS ≤ 5.0 cm were measured. Sites I and II, respectively, had 436 and 387 sampled individuals, and 29 and 24 species. Site III had 741 individuals and 29 species sampled. There was a significant difference in the number of tiller, individuals and basal area. In sites I and II, 72% and 88%, respectively, showed signs of regrowth. The fire changed the structure of vegetation, and regrowth was the main strategy used by species in sites with fire occurrence.

摘要 本研究旨在评估干旱草原火灾后的自然更新状况。我们选取了3个样地：样地I、II发生过火灾，样地III未发生火灾。每个样地设置1条样带，包含20个5×5米（即25平方米）的样方。对所有株高≥0.10米、基径（Diameter at ground level, DNS）≤5.0厘米的植株，测量其基径、总高度及萌蘖更新情况。样地I、II分别采集到436株和387株植株，隶属29种和24种；样地III共采集到741株植株，隶属29种。植株分蘖数、个体数量及基断面积均存在显著差异。样地I、II中分别有72%和88%的植株表现出萌蘖更新迹象。火灾改变了植被结构，萌蘖更新是火灾发生样地中多数物种采用的主要更新策略。