The month-long palaeoecology module at UvA is coming to an end. We have had two weeks of lectures and microscope work, an introduction to quantitative palaeoecology, and we just finished a week of fieldwork in Twente, which is in the easternmost part of the Netherlands.
Students working in the field (photo: M. Groot)
Will Gosling and I tried something new for the field excursion this year. We split the class into eight groups, and gave each group a set of pollen and phytolith samples from an ‘unknown location’. Unknown in this context means being from one of the eight primary sites that we would visit during the field excursion. The students were required to perform vegetation surveys and characterize soils at each of the primary sites that we visited. The goal of each group was to figure out which location their set of ‘unknown’ samples came from. Basically, we had them doing forensic palynology, with idea that they could then better visualize the different vegetation assemblages seen in the palaeoecological records. Continue Reading
Characterization of Neotropical ecosystems by their modern pollen spectra and organic chemical composition
Develop skills in pollen identification, pollen chemical characterization, and the analysis of organic biomarkers.
Examine ecological variation across an altitudinal gradient of nearly 4000 meters on the tropical western Andean flank.
Improve understanding of how ecosystems function in a biodiversity hotspot, and how they might be identified in the fossil record.
The considerable biodiversity of Neotropical ecosystems is under pressure from projected climate change and human activity. Modern ecosystems can be characterized by their pollen rain and organic chemistry, which can in turn provide information about ecosystem health and functioning. However, little is known about how pollen assemblage and chemical composition (of pollen and plants) vary along environmental gradients. Altitudinal transects provide an opportunity to study a range of environments and ecosystems with a relatively small geographic area. By improving our understanding of modern ecosystems we can improve our interpretation of fossil records, and consequently better understand how modern ecosystems came into being.
The main objectives of this PhD project are to:
Generate the first modern pollen assemblage and chemical data set for the Neotropics,
Characterize the landscape-scale variation in pollen assemblage and chemistry composition, and
Identify the key environmental drivers that determines pollen assemblage and chemistry composition variation.
Publication date: 27 July 2015 Closing date: 18 September 2015
Level of education: University (Masters)
Hours: 38 hours per week
Salary indication: €2,125 to €2,717 gross per month
Vacancy number: 15-286
Applications should be emailed to application-science@uva.nl, with in the subject line the position you are applying for and vacancy number (15-286). Please make sure all your material is attached in only one pdf. Applications should include a detailed CV including educational experiences, a list of research projects and/or publications, a letter of motivation, relevant work experience, and the names and contact addresses of two academic referees from whom a reference for the candidate can be obtained.
For more details, including information on how to apply, click here (UvA), or here (via academic transfer).
It’s very nice to be invited to write something for this blog, let me introduce myself a little bit.
I am a MSc Earth Sciences student at the University of Amsterdam. Currently I am working on my master thesis at Naturalis Biodiversity Center, under supervision of Niels Raes, Willem Renema and William Gosling. We are looking at species migration between Australia and Asia during the Miocene, and we compare it to migration between N and S America at the dawn of the Great American Biotic Interchange. To do so I’m analysing data on fossil occurrences in Australia and Southeast Asia. Hopefully this research will lead to interesting new insights.
Before starting my MSc Earth Sciences I did a bachelor in Biology at Leiden University. I decided to do a master’s in Earth Sciences because it offered a broader perspective of the natural world and its processes.
I like analysing and sorting out data like I’m currently doing for my thesis with fossil occurrence data. It also played a major role in my internship at TNO – Caribbean Branche Office, where I was involved in starting a database containing information on Aruba’s subsurface. During my internship I also experienced the “Green Aruba” conference and was involved in organising a geological excursion for some of the attendants. I am very interested in environmental issues and solutions, such as the transition to renewable energy. New technologies spike my interest a lot and I like being aware of innovations in a whole lot of fields.
Hopefully I will have my thesis ready within a couple of months, and can give an update about some of the findings.
University of Amsterdam Palaeoecology & Landscape Ecology researcher Stefan Engels explains his research into the fossil record from Lake Uddelermeer on Vroege Vogels, to watch Stefan in action visit: Boren in het Uddelermeer.
Valencia Castillo, B.G. (2014) From glacial to modern conditions: Vegetation and climate change under human influence in the Central Andes. PhD Thesis, Department of Environment, Earth & Ecosystems, The Open University.
Abstract
Conservation, restoration and management strategies are employed to maintain Earth’s biological diversity and physical environment to a near “natural” state. However, the concept of “natural” is generally inexact and may include degraded landscapes. In absence of long-term empirical data of natural baselines, impacted assemblages (human altered baselines) could be falsely assumed to be natural and set as conservation or restoration goals. Therefore, the identification of long-term ecological baselines becomes a pressing requirement especially in threatened biodiversity hotspots such as the tropical Andes that were under human pressure for several millennial.
This thesis aims to identify ecological baselines for tropical Andean ecosystems based on multi-proxy palaeoecological reconstructions from three Andean lakes. Trends of vegetation change are used to identify when landscapes became anthropogenic in the Andes. Because vegetation assemblages at c. 10 ka experienced negligible anthropogenic impacts and had modern-like climate condition, this time was considered the most recent period likely to provide insight into natural ecological baseline conditions.
Changes in vegetation assemblages were evaluated over time departing from 10 ka around Miski and Huamanmarca, two sites that remained virtually impervious to human impacts. Baselines in Miski and Huamanmarca drifted continuously over time and showed that baselines are dynamic entities. The vegetation assemblages derived from Miski and Huamanmarca suggest that that human impact was not homogeneous throughout the Andean landscape.
Once baselines were defined it was possible to evaluate if the spatial distribution of Andean woodlands represented by Polylepis was a product of human impacts. A MaxEnt model generated based on 22 modern environmental variables and 13 palaeoecological vegetation reconstructions showed that Polylepis woodlands were naturally fragmented before humans arrived in South America (14 ka). However, the influence of humans during the mid and late Holocene enhanced the patchiness of the forest generating a hyper-fragmented landscape.
Two weeks ago I attended the biannual International Biogeography Society (IBS) conference in Bayreuth, together with 600+ other people from more than 50 different countries. This IBS conference, my first IBS meeting, proved to be an exciting event during which I met scientists from many different disciplines and heard talks on cutting-edge biogeographical research.
The IBS conference was held in the Bavarian city of Bayreuth, in the middle of the biodiverse landscape of Upper Franconia. This landscape provided the training ground for Alexander von Humboldt, the founder of the field of biogeography. The 4-day conference included a wide variety of symposia and many, many posters. The conference dinner in the German Steam Train Museum was highly memorable. The conference was closed by a lecture from Daniel Simberloff, once a doctorate student of Edward O. Wilson, who received the Wallace Award for his outstanding contributions to invasion ecology.
I had a talk in the plenary symposium of ‘Ecosystem response to past climate change’, organized by David Nogués-Bravo and Francisco Rodríguez-Sánchez. The symposium covered the dangers of climate change to biodiversity and tried to assess if the range and rate of adaptation, migration, persistence, or extirpation, that are registered in deep-time records, palaeorecords, and the recent past, are adequate responses for predicted climate change in the future. I addressed this issue from the point of view of a small remote island, where migration is obviously a limiting factor. I showed how I reconstructed climate and its effect on island biota during the last 40,000 years using long-term palaeoecological records from Mauritius (de Boer et al, 2013 & 2014). These records show that different climate regimes result in different ecosystem response to climate change in the past. Local extirpation or population collapse of larger vertebrates was a natural phenomenon in the lowlands of Mauritius due to frequent climate extremes (I will discuss this in more detail in my next blog; de Boer, 2015). Despite these population collapses, island biota have always (in the timeframe of my records) survived natural climate change. Therefore, my take home message was not to focus on the effects of (future) climate change alone. Other key components of global change, such as invasive species and habitat destruction, are more imminent threats to the biodiversity of many islands. For more information on my research, including publications, click here.
More information on the IBS read on (below) or visit the IBS website or blog. All abstracts and other details of the IBS conference in Bayreuth can be found here. The next IBS meeting will take place in Salvador, Bahia (Brazil) in March 2017.
Students examining a sediment core extracted with a Russian corer
Last week, Will – our new associate professor at the University of Amsterdam – joined us on the field residential module of the undergraduate “Paleoecology” course; 7 days exploring the sediments and vegetation of the Twente region of the Netherlands. The experience provided Will with a lot of information on Dutch language, landscapes, and students; which should be useful to him next year as he will be coordinating the course!
Students examining peat exposures.
During this very intensive (4-week) paleoecology course, students get background lectures in past environmental change, learn to identify microfossils in the laboratory (pollen and chironomids), and go on the excursion to experience fieldwork. The field module involves excursions during the day, when students have to identify plant species indicative of different vegetation types in relation to soil nutrient availability and moisture content. The evenings are reserved for the students own paleoecological research investigation; this year students were reconstructing the vegetation history and climate change during the late-glacial from a lake sediment core from Germany. Once data collection was completed the students had to interpret the pollen assemblages they found using the knowledge of modern day ecosystems they gained throughout the week. On the final evening they presented their work to the whole group. The final results they achieved were quite impressive.
Students presenting findings from the days work
I am very curious as to what the course will be like next year, led by Will, and how he will tweak and turn it to his liking.
Frazer Matthews-Bird’s video on his PhD research examining long-term (>50 year) climate change from fossil insects (chironomids) has been shortlisted for the American Geophysical Union (AGU) student competition prize. Please watch Frazer’s video and “Like”; the most liked video will win free entry into the AGU Fall meeting 2014.
Ecology of the past 