Compositional Similarity of Urban Green Areas in Southeastern Brazil

ABSTRACT Urban afforestation greatly contributes to the ex situ conservation of native species in urban centers of Brazil. In this way, the aim of the present work was to analyze the similarity of the arboreal-shrub flora among urban afforestation in southeastern Brazil. For this analysis, a binary matrix with data of 283 species present in 20 municipalities in the Southeastern Region of Brazil was adopted, in which the Principal Component Analysis (PCA) was also used aiming at enabling refinement in the grouping obtained by the floristic similarity (FS) of Sørensen with similarity from values provided by PCA. FS among municipalities was intermediate, but the highest similarity of urban flora was found among the geographically closest municipalities. In the southeastern region, 283 species were recorded, being distributed in 71 botanical families, with Fabaceae having the largest number of species, and with emphasis on the predominance of exotic plants over native plants.

摘要 巴西城市中心城区的城市造林活动，对本土物种的迁地保护（ex situ conservation）具有显著贡献。为此，本研究旨在分析巴西东南部各城市造林项目间木本-灌木植物区系的相似性。本次分析采用覆盖巴西东南部20个市域、涵盖283个物种数据的二元矩阵，并引入主成分分析（Principal Component Analysis, PCA），以优化基于索伦森（Sørensen）植物区系相似性（floristic similarity, FS）所得聚类结果的精细程度。研究结果显示，各市域间的植物区系相似性处于中等水平，但地理距离最接近的市域间，其城市植物区系相似性最高。本次研究在巴西东南部区域共记录到283个物种，隶属于71个植物科，其中豆科（Fabaceae）的物种数量最多，且整体呈现外来物种占比高于本土物种的显著特征。