Phytolith production in non-woody plants from the Atlantic Forest on islands of the Paraná River, Brazil

Abstract

Phytolith reference collections of modern plants (RC) are essential tools for understanding and disseminating variations in phytolith production both within and among plant families, thereby playing a fundamental role in studies of biological indicators. This study aimed to assess the phytolith production (quantity and diversity; redundancy and multiplicity) of the main species from the vegetation of the Três Ilhas Archipelago in the Upper Paraná River, Brazil. Phytoliths were extracted from the leaves of 48 species across 25 families, including liana, subshrub, herb, and bamboo life forms, using the dry ashing method. The extracted material was quantified and prepared as temporary slides with immersion oil, enabling phytolith identification and counting. Phytolith production data were analyzed using descriptive statistics and non-metric multidimensional scaling (nMDS). Phytoliths were identified in 25 species, representing 16 families from liana, herb, subshrub, and bamboo life forms. A total of 25 phytolith morphotypes were identified, with monocots showing higher phytolith abundance, and eudicots exhibiting greater morphotype diversity, ranging from 1 to 7. The most redundant morphotype in monocots was Bilobate, found in four species, while the most common in eudicots was Spheroid ornate, present in 16 species. The Lythraceae family, known for producing Conical phytoliths, showed significant production of Oblong morphotypes in this collection. No new morphotypes were identified, and the findings largely align with the current literature for most of the studied families. This research provides essential data for paleoenvironmental reconstruction studies of the Três Ilhas Archipelago and similar environments, complementing the previous work on this site and vegetation.