Influence of Pinus taeda plantation on the seed bank in an Araucaria Rainforest region

Abstract This study aimed to evaluate the effect of a Pinus taeda plantation on the floristic and species composition of the seed bank in remnant of the Araucaria Rainforest (FOM). For this purpose, a total of 160 samples were collected from the seed bank, 80 of a FOM remnant and 80 from a P. taeda plantation. The samples were placed to germinate in two different greenhouses, under 35% and 75% shading level. A total of 11,669 woody and herbaceous individuals were counted, distributed in 31 botanical families and 84 species. The families Asteraceae and Poaceae were the most representative in richness of herbaceous species. With regard to woody species, Solanaceae and Asteraceae were the most representative in both areas. The species P. taeda was recorded only in the seed bank of the plantation. The seed bank of the pinus plantation was characterized mainly by the low richness of woody species, which shows its influence on the seed stock. On the other hand, the FOM remnant seems not to be influenced by the proximity of the pinus plantation to it is seed bank.

摘要 本研究旨在评估火炬松（Pinus taeda）人工林对南洋杉雨林残存地（Araucaria Rainforest，以下简称FOM）种子库的区系组成与物种构成的影响。为此，研究人员共采集160份种子库样本，其中80份取自该南洋杉雨林残存地，80份取自火炬松人工林。随后将所有样本分别置于两种不同的温室中开展萌发实验，设置35%与75%两种遮光度。本研究共计统计得到11669株木本与草本个体，隶属于31个植物科、84个物种。其中，菊科（Asteraceae）与禾本科（Poaceae）在草本物种丰富度方面占据主导地位；就木本物种而言，茄科（Solanaceae）与菊科在两个样地中均为优势类群。火炬松（Pinus taeda）仅在该人工林的种子库中被记录到。该火炬松人工林的种子库以木本物种丰富度偏低为主要特征，这体现了其对种子库的影响；与之相反，该FOM残存地的种子库似乎并未受到附近火炬松人工林的影响。