Population structure, spatial distribution and phenology of Anacardium humile A. St.-Hil. (Anacardiaceae) in cerrado stricto sensu

ABSTRACT This study determined the size structure, spatial distribution, and phenology of individuals from a population of Anacardium humile A. St.-Hil. in a cerrado stricto sensu area. Four sample plots (100 × 100 m each) were randomly selected in the Quilombola Kalunga land. Within the plots, we counted the number of individuals and measured the height, basal diameter, number of tree branches and recorded their location and the presence of rocky outcrops. For the phenological analysis, sixteen individuals were monitored between May 2016 and April 2017. A total of 417 individuals were inventoried, which resulted in an average density of 104.25 ind ha-1 (± 60.35). The abundance of individuals was higher in the rocky outcrops and with an aggregate spatial distribution. The population is self-regenerating. Phenological changes were concentrated in the dry season and were influenced by lower precipitation rates, maximum temperature, and relative humidity.

摘要 本研究明确了巴西狭义塞拉多植被（cerrado stricto sensu）区域内矮小腰果（Anacardium humile A. St.-Hil.）种群个体的大小结构、空间分布格局与物候特征。本研究在卡隆加奎隆博拉（Quilombola Kalunga）领地内随机选取了4块单块面积为100×100 m的样地，于样地内统计个体总数，测定植株高度、基径与分枝数，并记录其空间位置及岩石露头（rocky outcrops）的分布情况。针对物候分析，本研究于2016年5月至2017年4月期间对16株个体开展连续监测。本次调查共记录到417株个体，平均种群密度为104.25株·公顷⁻¹（±60.35）。岩石露头区域的个体丰度更高，种群整体呈聚集型空间分布格局。该种群具备自然更新能力。物候变化集中发生于旱季，且受低降水量、最高气温与相对湿度的共同调控。