Prado Júnior J, Schiavini I, Vale V, Lopes S, Arantes C, Oliveira A P
Laboratório de Ecologia Vegetal, Instituto de Biologia, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil.
Laboratório de Ecologia Vegetal, Departamento de Biologia, Universidade Estadual da Paraiba, Campina Grande, PB, Brazil.
Braz J Biol. 2015 May;75(2):339-46. doi: 10.1590/1519-6984.12413.
The specific leaf area (SLA) has been related to environmental disturbances, showing a positive correlation between the disturbances intensities and SLA in a plant community. These studies, however, assessed the responses of plant community as a whole, neglecting species attributes, such as the position in the vertical stratum of forests. Considering the importance of SLA to understand forest ecological processes, this study aimed to determine the influence of the disturbance regime on the SLA of understory species, considering that, unlike for communities as a whole, an increase in the disturbance intensity implies a decrease in SLA of understory species. This study was conducted in nine understories of seasonal forests in Brazil. The most abundant species were selected and their SLA were evaluated. The variability of SLA among populations in different forests was analyzed by Student's t-tests. The SLA of the understories (SLAU) was also compared by an adaptation of the Community-weighted mean index. The comparison of species SLA showed significant differences among the populations of understories under different disturbance regime, showing a decrease in SLA with an increase in the disturbance intensity. Similar results were found for the SLA of understories communities (SLAU), corroborating our hypothesis. The correlation between a reduction in species SLA and in SLA of understory with an increase in disturbance intensity, contradicted the trend observed in the literature for the community as a whole. This study highlights the importance of the evaluation of SLA in understories, as an indicator of the successional stage of communities.
比叶面积（SLA）与环境干扰有关，在植物群落中干扰强度与SLA呈正相关。然而，这些研究评估的是整个植物群落的响应，忽略了物种属性，例如在森林垂直层次中的位置。考虑到SLA对于理解森林生态过程的重要性，本研究旨在确定干扰 regime 对林下物种SLA的影响，因为与整个群落不同，干扰强度的增加意味着林下物种SLA的降低。本研究在巴西季节性森林的九个林下进行。选择了最丰富的物种并评估其SLA。通过学生t检验分析不同森林中种群间SLA的变异性。林下（SLAU）的SLA也通过对群落加权平均指数的一种改编进行比较。物种SLA的比较显示不同干扰 regime 下林下种群之间存在显著差异，表明随着干扰强度的增加SLA降低。林下群落（SLAU）的SLA也得到了类似结果，证实了我们的假设。物种SLA和林下SLA随着干扰强度增加而降低之间的相关性，与文献中观察到的整个群落的趋势相矛盾。本研究强调了评估林下SLA作为群落演替阶段指标的重要性。
