Establishing phytolith analogs for four forest formations of lowland Ecuador: Results and applications to archaeological and paleoenvironmental interpretation

Summary

As part of the Phytoliths in the Flora of Ecuador Project (PFE) (Pearsall 2016), phytolith assemblages from 82 surface soil samples from four distinctive vegetation formations, xerophytic coastal forest (Chanduy valley), mixed deciduous/evergreen forest (Jama region), coastal evergreen forest (Bilsa Biological Reserve), and Amazonian lowland forest (Jatun Sacha Biological Reserve) were studied, with the goal of establishing phytolith vegetation signatures to facilitate archaeological and paleoenvironmental phytolith interpretation. Proportions of diagnostic phytoliths were examined for each locality, separately, and phytolith patterning within the combined data set, i.e., all individual soil samples considered together, was explored through multivariate statistical analysis. Comparison of coastal (Bilsa) and Amazonian (Jatun Sacha) evergreen forests shows they cannot be distinguished using commonly occurring phytoliths and the rarer forms included in our study. Phytoliths are robust for identifying the evergreen forest biome. Comparison of xerophytic forest (Chanduy), dry (mixed deciduous/evergreen) forest (Jama), and moist forest of the coastal plain (Bilsa) reveals distinctive differences among these forests. Potential applications of our results include investigating the distribution of dry tropical forests in the past, identifying changes in moisture regimes over time, and tracking human impacts on different types of vegetation.

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Individual & Institutional Roles

Project Director(s): Deborah M. Pearsall

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