Silicophytolith reference collections of different plant communities from Argentina

Abstract

The production of silicophytoliths, plant amorphous silica biomineralizations, has a close relation with phylogeny, although environmental and developmental conditions also affect the silicification process. In this sense, different plant communities, depending on their specific composition, will produce different silicophytoliths, both in qualitative and quantitative terms. The description of the most abundant and characteristic types of silicophytoliths of a particular plant community is an essential tool for botanical studies and, especially, for the interpretation of the fossil phytolith record, and hence to paleobotanical, archaeological and pedological studies. In the present chapter, the reference collection of the silicophytolith production of species belonging to different plant communities from Argentina, is presented. In particular, the silicophytoliths produced in species developed in natural grasslands (Paspalum quadrifarium and "flechillar" communities), grasslands affected by agricultural practices and wetlands from Pampean region, and peatland and grasslands species from Tierra del Fuego are described and compared. The main families represented in these communities are Poaceae, Cyperaceae, Asteraceae and Juncaceae, which greatly differ in their silicophytolith production. Since different subfamilies within Poaceae family characterized the studied grasslands, and silicophytolith production also differs between subfamilies, the grass communities could be differentiated through their phytolith assemblages. In general, silicophytolith production involves the silicification of epidermis, however parenchymatous, sclerenchymatic and xylematic tissues are frequently found silicified.