New paper: Quantification of large herbivore populations… using dung fungal spores

Baker et al. (2016) Quantification of population sizes of large herbivores and their long-term functional role in ecosystems using dung fungal spores. Methods in Ecology and Evolution. http://dx.doi.org/10.1111/2041-210X.12580

Article first published online: 12 MAY 2016

You’ll be interested in our latest paper developing the dung fungal spore method and published in Methods in Ecology and Evolution.

With this paper and our 2013 review (see this post), my co-authors and I open the path for improved quantitative reconstruction of large herbivore population sizes. These quantitative reconstructions will be critical for any future research to contribute to topical themes such as rewilding, megafauna and ecosystem function.

Most of the research examining the relationship between large herbivores and their impact on landscapes has used extant studies. An alternative approach is to estimate the impact of variations in herbivore populations through time using fossil dung fungal spores and pollen in sedimentary sequences. The ponds at Oostvaardersplassen provided the ideal setting  to develop further the dung fungal spore method and determine the relationship between spore abundance in sediments and herbivore biomass densities. Our results indicate that this method provides a robust quantitative measure of herbivore population size over time.

The Oostvaardersplassen, The Netherlands, is a nature reserve established on polder land. Re-wilding was initiated at this site from 1983 with the introduction of free-ranging Heck cattle (Bos taurus Linnaeus) in 1983, Konik horses (Equus ferus caballus Linnaeus) in 1984 and red deer (Cervus elaphus Linnaeus) in 1992. Moreover, 1001 ponds were created throughout the reserve between 1985 and 2000 for avian biodiversity. The site is managed with a policy of minimal intervention, i.e. the population size of freely roaming large herbivores is not controlled by culling, no supplementary feeding is given during winter and no management intervention is implemented to maintain vegetation.

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New paper: Phytolith analysis reveals the intensity of past land use change in the Western Ghats biodiversity hotspot.

Nogué, S., Whicher, K., Baker, A.G., Bhagwat, S.A. & Willis, K.J. (2016) Phytolith analysis reveals the intensity of past land use change in the Western Ghats biodiversity hotspot. Quaternary International.

Article first published online: 8 March 2016.

 

New paper: Pollen productivity from the old-growth forest of Białowieża differs from that of cultural landscapes across Europe

Baker, A.G., Zimny, M., Keczyński, A., Bhagwat, S.A., Willis, K.J., Latałowa, M. (2016) Pollen productivity estimates from old-growth forest strongly differ from those obtained in cultural landscapes: Evidence from the Białowieża National Park, Poland. The Holocene 26, 80-92. http://hol.sagepub.com/content/26/1/80

Available online: 29 July 2015

Pollen productivity estimates of individual plant species are necessary when determining changes of vegetation cover in the past using fossil pollen. To date, studies describing pollen productivity in lowland temperate Europe have been carried out in cultural landscapes showing low forest cover and dominated by human activities. However, these may be of limited use when applied to reconstruct past land cover, for instance, from pre-agricultural landscapes.

The aim of this paper was to ascertain whether pollen productivity from the closed canopy old-growth forest in the Białowieża National Park, Poland, where human impact has been minimal for nearly a century, is different from that calculated in much more open landscapes. We asked: how much does forest antiquity and structure influence the amount of pollen released from particular taxa?

Our results demonstrate that pollen from forest grasses and forest hazel is six times more under-represented in old-growth forest than that estimated from cultural landscapes. This finding reinforces the idea that pollen productivity can vary in response to changes in the prevailing environmental setting and we present for the first time a quantification of this variability, likely induced by differences in light availability.

The Forest of Białowieża is a flagship ecosystem in European nature conservation. It covers about 1450 km2 straddling the border between Poland and Belarus. Białowieża is the largest expanse of lowland temperate closed canopy forest in Europe and it is unique for the complete assemblage of native trees, large herbivores and carnivores, for its size and for its antiquity.

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New Paper: Looking forward through the past: identification of 50 priority research questions in palaeoecology

Seddon A.W.R., Mackay A.W., Baker, A.G., et al. (66 other authors) (2014) Looking forward through the past. Identification of fifty priority research questions in palaeoecology. Journal of Ecology. 102, 256–267. Link.

Article first published online: 16 December 2013

This multi author, horizon-scanning paper presents the 50 priority questions in palaeoecology that were identified during a workshop that Alistair, Anson and I organised in December 2012 in Oxford.

New paper: Do dung fungal spores make a good proxy for past distribution of large herbivores?

Baker, A.G., Bhagwat, S.A., Willis, K.J. (2013) Do dung fungal spores make a good proxy for past distribution of large herbivores? Quaternary Science Reviews 62, 21–31. http:/www.dx.doi.org/10.1016/j.quascirev.2012.11.018

Available online: 27 December 2012

Abstract: The importance of herbivory as a long-term driver of ecosystem change is a topic that has been hotly debated over the past few years. An understanding of the interaction between herbivores and ecosystems is particularly important for conservation policies aimed at re-wilding.

Dung fungal spores have been highlighted as an important potential proxy to reconstruct large herbivore densities across past landscapes. However, this proxy appears to have been used and interpreted in a variety of ways in addition to highly variable taxonomic identification of dung fungal spores.

Here we review studies that have utilised fungal spore assemblages to assess past herbivore presence and test the validity of this method. We aim to determine whether there is a set of identifiable dung fungal spores that can unequivocally track variation of large herbivore activity through time and across regions.

Our meta analysis identifies: (1) spore types that are commonly found to be indicative of large herbivores and their geographical ranges, (2) linkages between these spores and their biological origin, and (3) the most appropriate quantitative method to express their abundance for comparisons through time and across sites.