First report of modern pollen deposition in moss polsters in a semiarid area of Bahia, Brazil

Abstract

Recent studies have shown that pollen analyses of natural substrates can produce data valuable for understanding the local pollen productivity and dispersal, deposition, and preservation potential of pollen grains. In this study, we aimed to acquire novel information about the dynamics and preservation of pollen in Caatinga environment through the palynological study of moss polsters. Samples of moss polsters in soil (MPS) and on rock (MPR) were collected from the Canudos Biological Station in the Bahia State (Brazil) and subjected to standard chemical treatments for the extraction of pollen residues. In total, 372 pollen types were recorded from the samples of which the taxonomical affinity of 140 was determined. The most represented families were Fabaceae (23 pollen types/16.42%) and Asteraceae (12 pollen types/8.57%). The MPS samples had a higher pollen concentration (21,042.04 pollen grains/cm²) than the MPR samples (7,829.35 pollen grains/cm²). On the other hand, the MPR samples had a greater diversity (68.26% of the identified pollen types). Qualitative analysis showed that the plants of shrub and subshrub habits had the greatest representation among the pollen types (35.0%). Overall, moss polsters proved to be excellent natural air pollen collectors in Caatinga environment, provided they had moist microhabitats for their development.

Keywords

• Brazilian NE
• moss
• natural pollen trap
• pollen rain
• semiarid