Potential of soil phytoliths, organic matter and carbon isotopes for small-scale differentiation of tropical rainforest vegetation: A pilot study from the campos nativos of the Atlantic Forest in Espírito Santo State (Brazil)
Calegari M.R.,West Parana State University |
Madella M.,University Pompeu Fabra |
Madella M.,IMF Spanish National Research Council CSIC |
Tagliari Brustolin L.,West Parana State University |
And 5 more authors.
Quaternary International | Year: 2016
A truthful vegetation reconstruction is essential for understanding the historical trajectory of climate change and as well as the nature and extent of human impact on ecosystems. A classical approach to these studies is the use of pollen to identify flora composition and variability over time. However, the use of pollen is not always viable due to lack of depositional environments and general taphonomic processes, such as edaphic conditions. The most durable plant fossils, with widespread presence in diverse depositional realities, are phytoltihs. These proxies are common, well preserved in soils and with great potential for the detection of vegetation signals at micro and meso-level. Therefore, phytoliths are an important tool for recognising variability in major biomes such as tropical forests. In this study we illustrate the results of a pilot project in the Atlantic Forest (Mata Atlântica) of Brazil. The Atlantic Forest is a very diverse ecosystem and its environmental history is still poorly known, especially in relation to the origin and development of non-forested islands (campos nativos) within the forest. Campos nativos create a mosaic with the Mata Atlântica and their current persistence is due to a combination of topographic effects, hydrology and soil. Our work evaluated the potential of soil phytolith, total organic content (TOC) and δ13C of two grassland/savannah campos nativos in the Vale Nature Reserve in Linhares (state of Espírito Santo). The results from isotopic analysis show the relevance of C3 plants since the beginning, and for all the sedimentary history, in both campos nativos. The soils of the nativos are spodosols and, surprisingly, the phytolith composition has been drastically affected by the edaphic conditions. The phytolith assemblages are often impoverished, especially in the soil sandy layer. However, the assemblages still show an important local floristic component (micro scale) with an input from the surrounding vegetation (meso-scale). © 2016.
Phillips C.,University of Cambridge |
Lancelotti C.,IMF Spanish National Research Council CSIC |
Lancelotti C.,University Pompeu Fabra
American Journal of Primatology | Year: 2014
Most primate populations remain unobservable; therefore, researchers depend on the analyses of indirect evidence encountered at a study-site in order to understand their behavioral ecology. Diet can be determined through the analyses of scats or feeding remains encountered on-site. This allows aspects of their dietary repertoire to be established, which has implications both for conservation efforts (by locating food resources), and for understanding the evolution of hominin diet (if used as referential models). Macroscopic inspection of fecal samples is a common method applied to ascertain a primate population's diet. However, new approaches are required to identify food-items unrecognizable at this level. We applied a dry ash extraction method to fecal samples (N=50) collected from 10 adult chimpanzees in Kanyawara, Kibale National Park, Uganda and also to plant parts (N=66) from 34 species known to be included in the diet of this community of apes. We recovered phytoliths in 26 of the 34 plant species. Fifteen phytolith morphotypes were only detected in 14 plant species (termed "distinct" phytoliths). We used these distinct phytoliths to identify plant foods (i.e., that they were associated with) in fecal samples. We then validated findings by checking if the 10 chimpanzees had eaten parts of these plants ∼24hr prior to fecal sample collection; six plant species associated with five distinct phytoliths had been eaten. Finally, we compared plant foods identified in fecal samples from phytolith analyses with plants that had been identified from macroscopic inspection of the same fecal samples. Findings from phytolith analyses corroborate with those from macroscopic inspection by expanding the total number of plant species identified per fecal sample (i.e., we identified certain plant parts that remained unrecognizable at macroscopic level). This study highlights the potential of phytolith analyses of feces to increase our knowledgebase of the dietary repertoire of primate populations. Am. J. Primatol. 76:757-773, 2014. © 2014 Wiley Periodicals, Inc.