Ecosystem engineering by blind mole rats in sandy grasslands - our new paper in PeerJ

Our new paper about the ecosystem engineering effect of Lesser blind mole rats has recently been published in PeerJ.

The paper is open access and can be freely downloaded from the journal website (please click here). A new interesting feature that authors can opt-in to publish the whole peer review history, so that the review process is transparent to anyone who is interested. The peer review history of the paper can be found here.

Valkó, O., Kelemen, A., Kiss, O., Deák, B. (2022): Patch and matrix characteristics determine the outcome of ecosystem engineering by mole rats in dry grasslands. PeerJ 10: e14582. https://doi-org/10.7717/peerj.14582 [IF2021: 3.061]

 

Strictly protected pasque flower (Pulsatilla flavescens) growing on the mound of the strictly protected blind mole rat (Nannospalax (leucodon) transsylvanicus).

 

Summary of the paper

Background: Burrowing mammals are important ecosystem engineers, especially in open ecosystems where they create patches that differ from the surrounding matrix in their structure or ecosystem functions.

Methods: We evaluated the fine-scale effects of a subterranean ecosystem engineer, the Lesser blind mole rat on the vegetation composition of sandy dry grasslands in Hungary. In this model system we tested whether the characteristics of the patch (mound size) and the matrix (total vegetation cover in the undisturbed grassland) influence the structural and functional contrasts between the mounds and the undisturbed grasslands. We sampled the vegetation of 80 mounds and 80 undisturbed grassland plots in four sites, where we recorded the total vegetation cover, and the occurrence and cover of each vascular plant species. We used two proxies to characterise the patches (mounds) and the matrix (undisturbed grassland): we measured the perimeter of the mounds and estimated the total vegetation cover of the undisturbed grasslands. First, we compared the vegetation characteristics of the mounds and the surrounding grasslands with general linear models. Second, we characterised the contrasts between the mounds and the undisturbed grassland by relative response indices (RRIs) of the vegetation characteristics studied in the first step.

Results: Species composition of the vegetation of the mounds and undisturbed grasslands was well separated in three out of the four study sites. Mounds were characterised by lower vegetation cover, lower cover of perennial graminoids, and higher diversity, and evenness compared to undisturbed grasslands. The contrast in vegetation cover between mounds and undisturbed grasslands increased with
decreasing patch size. Increasing vegetation cover in the matrix grasslands increased the contrasts between the mounds and undisturbed grasslands in terms of total cover, perennial graminoid cover, diversity, and evenness. Our results suggest that mole rat mounds provide improved establishment conditions for subordinate species, because they are larger than other types of natural gaps and are characterised by less intense belowground competition. The ecosystem engineering effect, i.e., the contrast between the patches and the matrix was the largest in the more closed grasslands.

Co-seeding of grasses and forbs supports restoration: our new paper in Scientific Reports

Our new paper by Réka Kiss about our experiment testing priority effects in grassland restoration has recently been published in Scientific Reports.

The paper is open access and can be downloaded from the journal homepage (please click here).

Kiss, R., Deák, B., Tóth, K., Lukács, K., Rádai, Z., Kelemen, A., Miglécz, T., Tóth, Á., Godó, L. & Valkó, O. (2022): Co-seeding grasses and forbs supports restoration of species-rich grasslands and improves weed control in ex-arable land. Scientific Reports 12: 21239. https://doi-org/10.1038/s41598-022-25837-4 

Our aim was to test whether the timing of seed sowing has an effect on grassland recovery and to test how can we support the successful implementation of grassland restoration projects. Choosing the proper timing of seed sowing and the optimal amount and species composition of the sown seed mixtures are very important for maximising restoration success and saving costs.  The matrix of seed mixtures are generally the grass seeds, which have an important role in weed suppression. In large-scale restoration projects, it is not always possible to compose and use a diverse seed mixture in the entire area; thus, they often use low diversity grass seed mixtures. On the one hand, seed sowing of grasses leads to a rapid and predictable vegetation development, and we can expect a species-poor grass-dominated vegetation two or three years after seed sowing. On the other hand, increasing the diversity of these species-poor sown grasslands requires novel methods and a lot of extra work in the future.

In our project we sowed grass (Festuca pseudovina) seeds in 2014 and a diverse seed mixture (containing 20 forb species) in different combinations (together with the grass seeds, and 1, 2 and 3 years later). We studied the species composition of the developed communities and evaluated which solution is the best in terms of weed suppression.

Our results clearly showed that the best solution is sowing the diverse seed mixture together with the grass seeds. This treatment resulted in the most diverse vegetation, the lowest level of weed encroachment and the highest number of established target species. In large restoration sites, which are embedded in an agricultural landscape, the spontaneous establishment of target species is very unlikely, given their impoverished seed banks and the lack of propagule sources. In such areas, active introduction of target species is inevitable for restoring species-rich grasslands. Our results suggest that it is a much more practical and cost-effective solution to sow the diverse seed mixture together with the grass seeds, at the very first stage of grassland restoration.

Abstract

Sowing is widely used for the restoration of species-rich grasslands but still there are knowledge gaps regarding the most suitable application of different seed mixtures. We tested the effect of seed mixtures application timing on the establishment of sown forbs and weed control. 36 experimental plots with nine sowing treatments were established in an abandoned cropland in Hungary. Grass seeds, diverse forb seed mixture and the combination of the two were applied: diverse forb mixture was sown simultaneously or 1, 2 or 3 years after grass sowing, in plots sown previously with grass or in empty plots (fallows). All sowing treatments supported the rapid establishment of the sown species in large cover and hampered weed encroachment. Forbs performed better when sown into fallows than in grass-matrix and forbs establishment was worse in older fallows than in younger ones. Grasses expressed a strong priority effect, especially when forbs were sown at least two years later than grasses. We also investigated the relation between seed germinability, weather parameters and establishment success. Germination rate in the greenhouse could not predict the establishment success of forbs in the field and showed great differences between years, hence we recommend sowing target forbs in multiple years.

Grazing and ecosystem services in drylands - synthesis by Maestre et al. published in Science

The newest paper from the BIODESERT ERC project of Prof. Fernando Maestre has been published in Science. The paper gives an overview on the effects of grazing on the ecosystem service delivery  in global drylands. The study is based on the implementation of a robust field protocol in dry rangelands of six continents and 26 countries. It was our great pleasure that we could take part in this survey and we could represent the Hungarian rangelands. Our dry grasslands were situated in the least arid end of the whole studied gradient. Our part in the survey took approximately two months of intensive field survey and laboratory analysis, for which the help of our colleagues Katalin Lukács, Réka Kiss, Szilvia Radócz, Laura Godó and Sándor Borza was essential, many thanks!

The citation and the abstract of the paper:

Maestre, F.T.M. et al. 2022. Grazing and ecosystem service delivery in global drylands. Science 378: 915-920.

'Grazing represents the most extensive use of land worldwide. Yet its impacts on ecosystem services remain uncertain because pervasive interactions between grazing pressure, climate, soil properties, and biodiversity may occur but have never been addressed simultaneously. Using a standardized survey at 98 sites across six continents, we show that interactions between grazing pressure, climate, soil, and biodiversity are critical to explain the delivery of fundamental ecosystem services across drylands worldwide. Increasing grazing pressure reduced ecosystem service delivery in warmer and speciespoor drylands, whereas positive effects of grazing were observed in colder and species-rich areas. Considering interactions between grazing and local abiotic and biotic factors is key for understanding the fate of dryland ecosystems under climate change and increasing human pressure.'

The lead authors of the paper prepared a nice and informative video summary, please click here to see it.

 

International Meeting for PhD students in Botany in Poroszló

Between 22-25 September, we organized an International Meeting for PhD students in Botany in Poroszló, Hungary. This meeting was first initiated by Milan Chytry and Zoltán Botta-Dukát about twenty years ago, and it has a very nice tradition since then. Every second year, PhD students in botany meet somewhere in Central Europe and they share their research plans and results, and they can get advice from senior scientitst in a friendly atmosphere.

After a few years break do to the pandemics, finally this nice event could be organized in person. We were very happy that we could organize this event this year - Zoltán Botta-Dukát, Balázs Deák and Orsolya Valkó, from IEB CER Vácrátót.

There was a huge interest and we were almost 70 participants, from 16 countries :) The scientific program was very dense, but very interesting; the PhD students gave very impressive and high-quality presentations.

The venue of the conference was in Poroszló, in the Tisza-Lake Ecocentrum, which was a wonderful place for having such an event. During the (few) coffee breaks, we could visit the nice indoor and outdoor exhibitions and aquariums, which was a nice and refreshing activity. During the nights, there were two very interesting topical discussions about 'How can we translate the scientific results into practice?' and whether 'Quality or quantity counts more in science?', followed by a lively social program.

On Sunday, Balázs Deák led a half-day long excursion, where we showed the participants the natural beauties of the Hortobágy National Park, the alkaline grasslands and wetlands, loess grasslands, and of course, kurgans.

The event was supported by the Hungarian Ecological Society and the Hungarian Academy of Sciences, we are grateful for their support. We are thankful for all the participants for their enthusiasm and active participation in all the events. We are thankful for all the colleagues from IEB who helped us in the organization, especially József Nagy, Attila Lengyel and Miklós Kertész. We are thankful for the Hortobágy National Park Directorate for supporting the field trip.

Our 'Forefront' project received funding - our new research will start soon

Our research project was one of the ten funded Forefront projects by the National Research, Development and Innovation Office in 2022. This gives us a unique opportunity for strengthening our group and for studying our beloved research topics in the next five years. The project will start soon, from 1st October :)

The title of the project is ‘Grassland restoration based on nature-based solutions in agricultural landscapes: drivers at micro- and macro-scales’. The topic of the project aligns well to the current global and European policies, that have ambitious plans for supporting habitat restoration in agricultural landscapes. The Frontline project aims to provide a comprehensive framework for utilizing nature-based solutions in the restoration of semi-natural grasslands and in creating multifunctional agricultural landscapes. The ambition is a multi-scale and multi-site research program that by answering theoretical ecological questions provides evidence-based solutions for strategic restoration planning and for fine-tuning the agri-environmental schemes. The novelty of our work is that we will combine approaches of large-scale multi-site vegetation surveys with landscape ecology, seed ecology and historical ecology. First, we use a multi-site chronosequence approach and study the spontaneous and assisted grassland recovery in agricultural landscapes. We sample the vegetation in 300 recovering sites and evaluate diversity and species composition patterns as a function of small-scale environmental heterogeneity, landscape context and recovery time. Second, we analyze the temporal (seed bank) and spatial (seed rain) components of seed dispersal and test the effect of the local and landscape factors on the availability of seed sources. Finally, we study whether seeds from the seed sources can achieve successful establishment in the aboveground vegetation and test the importance of plant functional traits, landscape- and environmental filters in the establishment process from the seed sources in the recovery process. We aim to develop and test seed-based restoration methods for overcoming establishment limitation. The research will identify optimal settings of local and landscape factors where recovery is the most promising and support restoration prioritization by determining where we can rely on spontaneous recovery processes and where we need active restoration measures.

Finally, we can attend conferences :) The week in a nutshell: conferences on conservation biology, landscape ecology and archaeology

After three years, it was a real pleasure to finally attend conferences in person and to meet with colleagues who we haven't met for a long time. The last part of August was especially intensive and exciting as we attended/will attend in total four conferences :) And now we are very much looking forward to the two forthcoming conferences in Spain in September.

In a chronological order, we attended/will attend the following meetings in the past days

- European Congress for Conservation Biology, Prague: the biggest conference of the European conservation biologist community, with great talks, great symposia and of course great other programs. Balázs Deák was a member of the scientific committee and he also organized a thematic symposium entitled 'Synergy between nature and culture: the role of historical and sacred natural sites in biodiversity conservation'. This gap-filling symposium was very interesting and gave a great overview on this very important but less known topic. Besides, members of our group participated in the conference with oral presentations and speed presentations.

- Hungarian Conservation Biology Conference, Pécs: right after the European conference, we went to the Hungarian one, which had also great talks, and great programs. With Katalin Török we organized a roundtable discussion entitled 'From where to where we transfer propagules in grassland restoration?'. We had a very lively discussion about this controversiary topic. Besides, our group participated at the conference with several posters and the talk of Katalin Lukács.

- Hungarian Conference on Landscape Ecology, Nádudvar: Parallel with the above two conferences, there was another interesting Hungarian conference, on which Sándor Borza from our group participated with a presentation and a poster.

- Annual Meeting of the European Archaeological Association, Budapest: the largest European archaeological conference is also running this week. From our group, Balázs Deák and Ádám Bede will participate with one presentation and one poster each, in a section dedicated to kurgans.

Finally, some photos about our adventures in Prague :)

The symposium organized by Balázs about the synergies between nature conservation and culture.

The botanical garden of the Charles University is a hidden gem, with a very interesting exhibition of wetland and aquatic species.

We visited the famous U Fleku inn :)

In Prague, there are so many invasive nutrias. Once on an island of the Vltava river, we so as many as thirty individuals! They are not afraid at all from the tourists.

We visited the Lednice-Valtice UNESCO site both on the journey to and back from Prague. This is a great place and definitely worth a visit. Not only because the wonderful buildings and the spectacular and huge hedges, but also because there are wonderful natural habitats there, including meadows with large old trees and nice lakeshore vegetation.

Group photo at the ECCB conference :)