last glacial maximum | Ecology of the past

Human impact on forest cover in Europe during the last glaciation

February 27, 2019
riannevduinen

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

Human impact on forest cover in Europe during the last glaciation
By Rianne van Duinen
(currently studying for MSc Biological Sciences, Ecology & Evolution track at the 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.

Reference

Past and future global transformation of terrestrial ecosystems under climate change

August 30, 2018
WDG

Nolan, C., Overpeck, J.T., Allen, J.R.M., Anderson, P.M., Betancourt, J.L., Binney, H.A., Brewer, S., Bush, M.B., Chase, B.M., Cheddadi, R., Djamali, M., Dodson, J., Edwards, M.E., Gosling, W.D., Haberle, S., Hotchkiss, S.C., Huntley, B., Ivory, S.J., Kershaw, A.P., Kim, S., Latorre, C., Leydet, M., Lézine, A., Liu, K., Liu, Y., Lozhkin, A.V., McGlone, M.S., Marchant, R.A., Momohara, A., Moreno, P.I., Müller, S., Otto-Bliesner, B.L., Shen, C., Stevenson, J., Takahara, H., Tarasov, P.E., Tipton, J., Vincens, A., Weng, C., Xu, Q., Zheng, Z. & Jackson, S.T. (2018) Past and future global transformation of terrestrial ecosystems under climate change. Science 361, 920-923. DOI: 10.1126/science.aan5360

Long-Term Vegetation Dynamics in a Megadiverse Hotspot

February 20, 2018
WDG

Open access:

Montoya, E., Keen, H.F., Luzuriaga, C.X. & Gosling, W.D. (2018) Long-term vegetation dynamics in a megadiverse hotspot: The Ice-Age record of a pre-montane forest of central Ecuador. Frontiers in Plant Science 9, 196. doi: 10.3389/fpls.2018.00196

Vegetation History & Archaeobotany

February 12, 2017
WDG

I am delighted to report that I have recently been appointed as an Associate Editor for the journal Vegetation History & Archaeobotany (VHA). The journals scope is global and covers Quaternary environmental and climatic change, with a specific focus on the Holocene and pre-historic human impacts on landscapes; often linking palaeoecological and archaeological research. My remit with VHA is to provide expertise on tropical, and in particular South American, studies. Recent articles in VHA with a South American focus include:

Assessing the influence of glacial-interglacial climate changes on the dry forest vegetation along the southern edge of Amazonia (Whitney et al., 2014),
The role of fire in modifying Amazonian vegetation (Hermanowski et al., 2015), and
Modern pollen-vegetation relationships in Brazil and Argentina (Rodrigues et al., 2016).

I hope that over the next few years we can publish some more exciting articles on the tropics in VHA and I would therefore like to encourage you to submit interesting high quality original research, reviews, or short articles for our consideration.

To find out more about the journal and submit an article click here.

Flantua, S.G.A., Hooghiemstra, H., Van Boxel, J.H., Cabrera, M., Gonzlez-Carranze, Z., Gonzlez-Arrango, C. (2014) Connectivity dynamics since the last glacial maximum in the northern Andes: a pollen-driven framework to assess potential migration. Monographs Systematic Botany Missouri Botanical Garden, 128: 98-123. In: Stevens, W.D., Montiel, O.M. Raven, P.H. (eds.), Paleobotany and biogeography; A Festschrift for Alan Graham in his 80 year. Missouri Botanical Garden Press, St. Louis, USA. ISBN 978-0-915279-97-5.

One short story and five scientific papers thinking about different aspects of ecological change through time.

Chekhov in 1889 (http://tinyurl.com/ny2msd9)

Short story:

Checkhov, A. (1889) The Pipe

SUMMARY (Will): People have long been concerned about environmental change. Observations of phenological shifts, degradation of ecosystem services and climate change are clearly presented in Checkhov’s “The Pipe” (1889).The key difference is today we have a better idea of why these things are happening!?

Scientific papers:

Garcia, R.A., Cabeza, M., Rahbek, C. & Araújo, M.B. (2014) Multiple dimensions of climate change and their implications for biodiversity. Science 344 1247579
SUMMARY (Phil): This review highlights the alternative metrics used to quantify climate change at different spatial scales, each with its own set of threats and opportunities for biodiversity. It’s a very relevant paper for palaeoecologists, with implications for how we think about climatic estimates we generate, how we interpret ecological shifts in the assemblages we study, and for demonstrating the importance thinking spatially as well as temporally. It also shows how important palaeoecological data is for setting baselines and putting projected climatic change into context.

Garzón-Orduña, I.J., Benetti-Longhini, J.E. & Brower, A.V.Z. (2014) Timing the diversification of the Amazonian biota: butterfly divergences are consistent with Pleistocene refugia. Journal of Biogeography, early online.
SUMMARY (Will): Butterfly species diverged in the Neotropics during the Pleistocene (probably).

Mitchard, E.T.A. et al. (2014) Markedly divergent estimates of Amazon forest carbon density from ground plots and satellites. Global Ecology and Biogeography, early online.
SUMMARY (Will): It is difficult to work out how much carbon is in a tropical forest.

Stansell, N.D., Polissar, P.J., Abbott, M.B., Bezada, M., Steinmann, B.A. and Braun, C. (2014) Proglacial lake sediment records reveal Holocene climate changes in the Venezuelan Andes. Quaternary Science Reviews. 89, 44 – 55.
SUMMARY (Hayley): A study of three lake sediment records in the Venezuelan Andes to look at patterns of glacial variability, and how glaciers might have responded to changing climatic conditions during the last c. 12,000 years.

Still, C.J., Foster, P.N. & Schneider, S.H. (1999) Simulating the effects of climate change on tropical montane cloud forests. Nature, 398, 608–610.
SUMMARY (Nick): The paper attempts to model the impact of climate change on a number of cloud forests around the world by simulating atmospheric parameters at the last glacial maximum (LGM) and at twice today’s CO2 level. The models agrees with palaeoecological data of a downslope migration of the cloud forest at the LGM, while the 2xCO2 model shows reduced cloud cover and increased evapotranspiration, which results in a significant reduction in cloud forest supporting land area.

Gosling PhD thesis 2004

April 10, 2014
WDG

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)

Abstract:

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.

Supervisors: Dr. Francis Mayle (University of Leicester, now at University of Reading) and Dr. Nicholas Tate (University of Leicester)

Examined by: Prof. Henry Lamb (University of Aberystwyth) and Prof. Andrew Millington (University of Leicester, now at Texas A & M), April 2004.

To borrow a copy from University of Leicester Library search for my name or thesis title here (item ID 7507349613), or download directly: Volume 1, Volume 2, and CD.