We are seeking to recruit a Neotropical palaeoecologist to join the recently funded “The past peoples of Amazonia: Assessing ecological legacies” project(PIDr. Crystal McMichael, funding NWO, based within the Department of Ecosystem & Landscape Dynamics). The project aims to reconstruct cultural histories from lake sediments in northwestern Amazonia, and link past human activities with modern ecological observations. The project involves analyzing microfossils (including pollen, phytoliths, and charcoal), and the development of a transfer function that estimates past human impacts in tropical forest systems.
We are particularly looking for a candidate with expertise and experience, in:
Fieldwork in remote areas.
Quantitative analysis, including familiarity with R and Geographical Information Systems.
Gosling, W.D. (2004) Characterisation of Amazonian forest and savannah ecosystems by their modern pollen spectra. PhD Thesis, Department of Geography, University of Leicester.
WDG Bolivia (2002)
Controversy surrounds the Quaternary palaeoenvironmental history of Amazonia. It is unclear whether moist evergreen forest, savannah or seasonally dry forest dominated the Amazon basin at the last glacial maximum (c. 21,000 years B.P.). In part the uncertainty surrounding the palaeoenvironmental history of Amazonia stems from a poor understanding of the ecological significance of the fossil pollen records from the region. In order to improve interpretations of the fossil pollen record it is essential to better understand the nature of the pollen rain produced by modern ecosystems.
In this thesis, three Neotropical ecosystems equivalent to those alluded to above were characterised by their modern pollen rain. This was achieved by examining samples collected in artificial pollen traps located within permanent (50 x 200 m) vegetation plots in the Noel Kempff Mercado National Park area, Bolivia. In each plot 10 traps were sampled for one field season (September 1998 to September 1999, or September 2000 to September 2001) and 5 traps were sampled from two additional field seasons (between 1998 and 2001). Pollen counts of at least 100 grains were made for each trap. In total 318 pollen taxa were distinguished, of which 116 were identified. The characteristic pollen from each of the three ecosystems were determined through a series of steps: spatial and temporal variations were explored using Spearman’s Rank correlations, the distinctive taxa of each ecosystem were identified using Principal Components Analyses (PCA), and the representativity of the pollen for each ecosystem was examined by comparing pollen and vegetation abundances. These analyses revealed a small number of taxa that can be used to characterize these ecosystems. Further PCA showed that it is possible to differentiate between the ecosystems by assessing the relative proportions of Didymopanax, Alchornea, Anadenanthera, Melastomataceae/Combretaceae, Moraceae/Urticaceae, Myrtaceae, Palmae, Pteropsidia (trilete), Poaceae and Solanum. These findings mean that it is now possible to detect these ecosystems in the fossil pollen record and consequently further information regarding the nature of the vegetation change in the Amazon basin can be gained.