Crane migration – A scenic event of the Hortobágy

The Hortobágy, which is one of the most extended coherent nature close open habitats of Europe is an important part of the migration route of the Cranes nesting in Finland, the Baltic states and Russia. The migrating birds – after having a short break in the Hortobágy – fly towards to North Africa. Interestingly many of the Cranes arrived from Siberia: they made a quite long loop on their way to Africa. This year is an exceptional one with an exceptionally high number of cranes, their estimated number is 160 000.

Opposite to their migration in spring (when the Cranes just fly over the grasslands and wetlands of the Hortobágy) they spend a longer time here in this part of the year. The reason is that whilst in springtime the Cranes primarily focus on reaching the nesting areas as soon as possible, in autumn they have more time for migration. They spend their time in the Hortobágy for increasing their (and their youngsters’) fitness by relaxing a bit and feeding. They spend the nights in the wetlands (generally in the numerous shallow fishponds), and during the daytime they are feeding at the neighbouring arable lands and grasslands. The most scenic part of their daily routine is just before sunset, when they compose huge groups and fly back together to the wetlands for having a night rest.

Feeding in the grasslands of Nyírőlapos-puszta

Waiting for the cranes - spider nets in the sunset; Darassa-puszta

The first ones

Just a small group

  

Early arrivals to the fishpond

  

Cranes in the sunset; Darassa-puszta

Grassland restoration by seed sowing: when, what and how much?

Our aim is to answer these important questions to 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 (Deák et al. 2011). Usually they sow the grass seeds in a density of 20-40 kg/ha in the restoration projects. Choosing the right density is crucial: if we don’t sow enough seeds, it can lead to weed encroachment, but sowing too many grass seeds results in the formation of a dense canopy which act as a barrier for the germination of target species via microsite limitation. 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 (Török et al. 2010, Valkó et al. 2016a). 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 (Valkó et al. 2016b, 2018).

In our project we sowed grass (Festuca rupicola) 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 study the species composition and functional diversity of the developed communities and evaluate which solution is the best in terms of weed suppression.

Our preliminary results clearly show 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.

Here are some pictures about the experiment in October 2018.

In this plot, the diverse seed mixture and the grass seeds were sown in the same year (2014).

Here we sowed the diverse seed mixtures in 2015, i.e. 1 year after the grass seeds (2014).

Here we sowed the diverse seed mixtures in 2016, i.e. 2 years after the grass seeds (2014).

Here we sowed the diverse seed mixtures in 2017, i.e. 3 years after the grass seeds (2014).

Literature Cited

Deák, B., Valkó, O., Kelemen, A., Török, P. Miglécz, T., Ölvedi, T., Lengyel, Sz., Tóthmérész, B. 2011: Litter and graminoid biomass accumulation suppresses weedy forbs in grassland restoration. Plant Biosystems 145: 730-737.

Török, P., Deák, B., Vida, E., Valkó, O., Lengyel, Sz., Tóthmérész, B. 2010: Restoring grassland biodiversity: Sowing low-diversity seed mixtures can lead to rapid favourable changes. Biological Conservation 143: 806-812.

Valkó, O., Tóth, K., Kelemen, A., Miglécz, T., Radócz, S., Sonkoly, J., Tóthmérész, B., Török, P., Deák, B. (2018): Cultural heritage and biodiversity conservation – Plant introduction and practical restoration on ancient burial mounds. Nature Conservation 24:65-80.

Valkó, O., Deák, B., Török, P., Kelemen, A., Miglécz, T., Tóth, K., Tóthmérész, B. 2016a: Abandonment of croplands: problem or chance for grassland restoration? Case studies from Hungary. Ecosystem Health and Sustainability 2(2): e01208.

Valkó O., Deák B., Török P., Kirmer A., Tishew S., Kelemen A., Tóth K., Miglécz T., Radócz Sz., Sonkoly J., Tóth E., Kiss R., Kapocsi I., Tóthmérész B. 2016b: High-diversity sowing in establishment gaps: a promising new tool for enhancing grassland biodiversity. Tuexenia 36: 359-378.

Filming

This week we made a project video about the work in the Department of Ecology, University of Debrecen. The main aim of the film is to provide an overview on the life in the Department, on our research topics and showing the ‘essence of being an ecologist’ to the students. During the filming we had a ‘field action’ scene in the Hortobágy, one in the greenhouse, one in the lab and many others. I think that with the help of the Médiacentrum Debrecen we managed to make an exciting ‘movie’. 

The film will be ready in December. Till then some werk fotos.

PhD defense, Réka Kiss

I am happy to congratulate to my former PhD student, Réka Kiss who successfully (indeed, very succesfully, with summa cum laude) defended her PhD thesis recently.

Réka has been studying the role of seed bank and seed sowing in grassland restoration. She presented the key results of two novel and interesting research topics: 1, her literature review about the links between seed bank, climate change and restoration prospects in the open landscapes in the World and 2, establishment gaps, a novel tool for the restoration of species-rich grasslands.

The most important publications related to her dissertation are as follows

Kiss, R., Deák, B., Török, P., Tóthmérész, B.., Valkó, O. (2018) Grasslands and climate change – How can soil seed bank support community resilience? Restoration Ecology, 26, S141-S150.

Kiss, R., Sonkoly, J., Török, P., Tóthmérész, B., Deák, B., Tóth, K., Lukács, K., Godó, L., Kelemen, A., Miglécz, T., Radócz, Sz., Tóth, E., Balogh, N., Valkó, O. (2018) Germination capacity of 75 herbaceous species of the Pannonian flora and implications for restoration. Acta Botanica Hungarica, 60, 357-368.

Kiss, R., Valkó, O., Tóthmérész, B., Török, P. (2016) Seed bank research in Central-European grasslands - An overview. In: Murphy, J. (ed.) Seed Banks: Types, Roles and Research, Nova Science Publishers, 1-34.

Kiss, R. (2016) The role of soil seed bank in restoration and dynamics of Hungarian plant communities – A review of Hungarian seed bank research . Kitaibelia, 21, 116-135.

Valkó, O., Deák, B., Török, P., Kirmer, A., Tishew, S., Kelemen, A., Tóth, K., Miglécz, T., Radócz, Sz., Sonkoly, J., Tóth, E., Kiss, R., Kapocsi, I., Tóthmérész, B. (2016) High-diversity sowing in establishment windows: a promising new tool for enhancing grassland biodiversity. Tuexenia, 36, 359-378.

Török, P., Kelemen, A., Valkó, O., Miglécz, T., Tóth, K., Tóth, E., Sonkoly, J., Kiss, R., Csecserits, A., Rédei, T., Deák, B., Szűcs, P., Varga, N., Tóthmérész, B. (2017) Succession in soil seed banks and its implications for restoration of calcareous sand grasslands. Restoration Ecology, 26, S134-S140.

Godó, L., Tóthmérész, B., Valkó, O., Tóth, K., Kiss, R., Radócz, Sz., Kelemen, A., Török, P., Švamberková, E., Deák, B. (2018) Ecosystem engineering by foxes is mediated by isolation in grassland fragments. Ecology and Evolution, 8, 7044-7054.

We would like to congratulate Réka with some nice and memorable photos, taken in our favorite field days. :)