de Wolf, I.K., McMichael, C.N.H., Philip, A.L. & Gosling, W.D. (2022) Characterising Dutch forests, wetlands and cultivated lands on the basis of phytolith assemblages. Netherlands Journal of Geosciences 101, e17. DOI: 10.1017/njg.2022.14
This paper started off as a research thesis undertaken by Iris de Wolf at the University of Amsterdam as part of her BSc Biology degree in 2018. The project was supervised by Crystal McMichael and William Gosling and has subsequently been further developed. If you are student or researcher interested in undertaking a similar type of projects please get in touch.
Listen to Iris’s journal podcast speaking about the subject here.
Gosling, W.D., Miller, C.S., Shanahan, T.M., Holden, P.B., Overpeck, J.T. & van Langevelde, F. (2022) A stronger role for long-term moisture change than for CO2 in determining tropical woody vegetation change. Science 376, 653-656. https://doi.org/10.1126/science.abg4618
To access this article FREE through the Science author referral service click here.
For more on the palaeoecological dataset underpinning this research check out the PhD thesis of Charlotte Miller by clicking here or here.
Nascimento, M.N., Heijink, B.M., Bush, M.B., Gosling, W.D. & McMichael, C.N.H. (2022) Early to mid-Holocene human activity exerted gradual influences on Amazonian forest vegetation. Philosophical Transactions of the Royal Society B: Biological Sciences 377, 20200498. https://doi.org/10.1098/rstb.2020.0498
This project will increase our understanding of how past disturbances have influenced the biodiversity and structure of Amazonian rainforests. The coming years, we will work on reconstructing past fire and vegetation history of forest plots in Amazonia, and how that history relates to modern biomass and modern carbon dynamics. ALPHA is important for forest conservation, because results can be used to prioritize land for conservation. ALPHA results will also give an estimation of the Amazonian rainforests’ ability to sequester carbon, which is important for global carbon models. dr. C.N.H. McMichael received an ERC grant to research ALPHA in Amazonia together with 2 PhD students, 1 post-doc, 2 technicians and a senior-staff. At the beginning of March, the positions were filled, and our team was complete. But then COVID-19 happened… and our team was spread over continents!
To keep ALPHA going, we started with weekly virtual lab meetings. Because these fruitful discussions are online, other researchers soon joined from the US, UK and Jamaica. It is not your average “vrijmibo”, but very fun and a nice way to stay connected! One of the papers we have discussed is the “Asynchronous carbon sink saturation in African and Amazonian tropical forests” from Hubau et al (2020).
In 2015, Brienen et al. published an article about the growth and mortality of trees in Amazonian rainforests for the period of 1985 to 2015. Their results showed a decline of the carbon sink in Amazonian forests.
Now, Hubau et al. (2020) added results from African forest plots and compared the net carbon sink of the African and Amazonian forests. Instead of a long-term decline, African forests showed a stable carbon sink. The difference in their carbon sink was because more trees died in Amazonia, but not in African forests. But since 2010, a decline is also visible in the carbon sink of African forests. This suggests that the two forests have a different ‘saturation’ point in the carbon they can storage.
A statistical model with CO2, temperature, drought and forest dynamics was created to predict the carbon changes of the forests over time. This model predicts that the carbon sink of African forests will show a gradual decline and the carbon sink of Amazonian forests will decline fast.
Overall, this paper highlights that our rainforests may not be the carbon sink we had thirty years ago. We will need to reduce greenhouse gas emissions sooner, if we want to limit global warming. Also, this paper showed how important forest dynamics are to accurately model and predict the carbon storage of Amazonia. Hopefully, the ALPHA research project will make a contribution to this!
In spite of the challenges and uncertainties that the larger scientific community is currently facing, I am delighted and humbled to accept one of the British Ecological Society’s Ecologist in Africa research grant for 2020. The grant will support my historical ecology project whose main goal is to apply palaeoecological and archaeological proxies to investigate the extent of anthropogenic impacts on vegetation structure and composition of one of the Kenyan Central highlands before, during, and after the colonial period.
The Aberdare range forest provide an ideal setting for this study because they have been farmed by local populations since long before colonialism, and they were heavily impacted during colonial times because of their fertile soils. This pilot project aims to reveal the land-use and land-cover dynamics of the Aberdare range forest, and it is hoped that eventually similar studies will be undertaken in other parts of the Kenyan highland forests.
This is the first is a series of blog posts based on papers discussed at our “Amsterdam Palaeoecology Club” meetings. The APC meetings are organized to promote palaeoecological discussion and to help the scientific development of our MSc and BSc research students. At each meeting we discuss a paper and the progress of individual projects. Short summaries of the papers and discussions are then made by the student introducing the paper. First up is MSc researcher Rianne van Duinen with her thoughts on Kaplan et al. (2016).
Rianne on field work in Twente during the 2017 edition of the BSc Palaeoecology course at University of Amsterdam
We discussed the paper “Large scale anthropogenic reduction of forest cover in Last Glacial Maximum Europe“ by Kaplan et al. (2016) which was found by the group to be super interesting and it incited a lot of discussion. The paper was mostly concerned with the anthropogenic influences and past vegetation of Europe. The main conclusion was that humans had a very big impact on forests during the last glacial period through the use of fire. The authors suggest that human actions are the explaining factor for the low amount of forests cover suggested by pollen records during the last glacial maximum (c. 21,000 years ago). The suggestion from Kaplan et al. that human modification of forest cover through fire during the glacial links with a recent study from Sevink et al. (2018) that suggests, based on pollen and charcoal data from the Netherlands, that human use of fire altered forest cover into the Holocene. In our discussion it was also noted that animals (mega-herbivores) were not really taken into account or discussed, even though animals probably had a big impact on the vegetation (e.g. see Bakker et al., 2016). Furthermore, another discussion point was the charcoal records that were used in the Kaplan et al. study, more specifically the number of cores. Kaplan et al. only used three cores to map out the effect of charcoal. It would be interesting to see what happens when more data from more cores is used. The Global Charcoal Database has a lot of data on European cores (c. 38% of the cores are from Europe) so there is a lot of potential for this. All in all, the article by Kaplan et al. raised a lot of questions and opened up a nice discussion.
I recently joined the editorial board of Plant Ecology & Diversity at the invitation of editor-in-chief Laszlo Nagy (University of Campinas, Brazil). The journal focuses on ecological and evolutionary issues within plant biology with broad themes covering biodiversity, conservation and global change. Furthermore, I think this is a particularly interesting journal to be involved with because of its option for double-blind peer reviews, commitment to providing a platform for ‘negative results’ and ‘repeat experiments’, and its open access Grubb Review series (Nagy & Resco de Dios, 2016); which already includes many significant articles, including: Ashton (2017), Barbeta & Peñuelas (2016), Grubb (2016), Körner (2018), Valladares et al. (2016), and Wilkinson & Sherratt (2016). In addition to the invited Grubb Reviews the journal publishes: research articles, short communications, reviews, and scientific correspondence. My role on the editorial board will be to cover submissions related to tropical palaeoecology and biogeography. So please consider submitting to Plant Ecology & Diversity if you have some exciting new research or ideas that you think would be appropriate.
15:00 Predator avoidance and prey tracking in a Neotropical forest (Constant Swinkels, Wageningen University & Research)
15:20 The role of fig volatiles in pollinator specificity and fig diversity (Aafke Oldenbeuving, Naturalis Biodiversity Center)
15:40 Mangrove Atlantis: Can mangroves keep up with extreme land-subsidence? (Celine van Bijsterveldt, Royal Netherlands Institute for Sea Research)
16:10 The fate of forests in agro-forest frontier landscapes, implications for conservation (Madelon Lohbeck, Wageningen University & Research)
16:30 Trends in the variability of Specific Leaf Area of paramo vegetation during succession (Marian Cabrera, University of Amsterdam)
16:50 Succession dynamics of tree and soil fungal communities in regenerating tropical rainforests are strongly influenced by regional species pool and abiotic factors (Irene Adamo, Naturalis Biodiversity Center)
For those of you I have not had the pleasure of meeting yet, please allow me to introduce myself. My name is Yoshi Maezumi. I have recently been awarded a Marie Curie Fellowship for my research proposal FIRE: Fire Intensity in Rainforest Ecotones. I will have the honor of working with an extraordinary team of international, interdisciplinary researchers including Will Gosling, Crystal McMichael, Emiel van Loon, and Boris Jansen from the University of Amsterdam, Boris Vannière from the Université de Franche-Comté, Jose Iriarte from the University of Exeter, and Francisco Cruz from the University of São Paulo. Together we will examine the long-term role of fire in shaping Amazon Rainforest Ecotones.
My research is focused on paleofire (fire in the past) in Neotropical savanna and rainforest ecosystems. My current post-doctoral research at the University of Exeter is investigating the role indigenous fire management practices had on shaping the composition, structure, and flammability of modern Amazonian rainforests.
Recently introduced to a book by Bill Gammage entitled The Biggest Estate on Earth: How the Aborigines Made Australia. Gammage identifies five uses of indigenous fire: 1) to control wildfire fuel; 2) to maintain diversity; 3) to balance species; 4) to ensure abundance; 5) to locate resources conveniently and predictably. Gammage argues that our current regime is struggling with number one. These stages of fire management provide some really interesting food for thought for my Marie Curie Fellowship as I aim to develop new paleoecological techniques to analyze paleofire that will be used to model natural and anthropogenic drivers of paleofire activity.
I have been thinking a lot about what we do and do not know about paleofire. One of the ways we reconstruct past fire activity is through the use of charcoal preserved in lake sediments. Charcoal can tell us a lot about what past fires were like including what kind of plants were burning, how often fires occurred, and potentially how big a fire was. One of the more elusive components is paleofire intensity, or how hot a particular fire was. The temperature of a fire has important ecological implications, as hotter fires tend to cause more ecological damage. Lots of factors can contribute to fire intensity including droughts, fuel loads, vegetation composition and structure, fuel moisture, etc. All of this is to say that, fire intensity is complicated. Nevertheless, one of the main objectives of my Marie Curie research will be to compile what we currently know about the effect of modern fire intensity on the charcoal formation to figure out how that information can be used to interpret charcoal from the palaeorecord.
If you would like to join me on this ‘intense’ paleofire journey, (punny, I know, I just couldn’t resist), I am starting a weekly science blog called Her Science that will highlight the trials, tribulations, and triumphs of my Marie Curie research over the next few years.