Our new paper about plant trait - environment relationships at the meso-scale published in the Science of the Total Environment

Our new paper by Balázs Deák et al. about the plant trait distributions in topographically heterogeneous dry grasslands has recently been published in the Science of the Total Environment.

The paper is open access, and can be freely downloaded from the website of the journal (please click here).

Reference:

Deák, B., Botta-Dukát, Z., Rádai, Z., Kovács, B., Apostolova, I., Bátori, Z., Kelemen, A., Lukács, K., Kiss, R., Palpurina, S., Sopotlieva, D., Valkó, O. (2024): Meso-scale environmental heterogeneity drives plant trait distributions in fragmented dry grasslands. Science of the Total Environment 947: 174355.

For studying trait-environment relationships, we selected our favourite study system, kurgans (millenia-old ancient burial mounds built by nomadic steppe tribes) that are among the most widespread man-made landmarks in the Eurasian steppe and forest steppe zone (please see our previous publications on these mounds here). We have shown that even at the scale of a few meters, the environmental heterogeneity can considerably shape the distribution of plant traits. Since these small landmarks are characterised by various different microsites, the large trait variation on the mounds can considerably increase community resilience.

Abstract

Environmental heterogeneity shapes the patterns of resources and limiting factors and therefore can be an important driver of plant community composition through the selection of the most adaptive functional traits. In this study, we explored plant trait–environment relationships in environmentally heterogeneous microsite complexes at the meso-scale (few meters), and used ancient Bulgarian and Hungarian burial mounds covered by dry grasslands as a model habitat. We assessed within-site trait variability typical of certain microsites with different combinations of environmental parameters (mound slopes with different aspects, mound tops, and surrounding plain grasslands) using a dataset of 480 vegetation plots. For this we calculated community-weighted means (CWMs) and abundance models. We found that despite their small size, the vegetation on mounds was characterized by different sets of functional traits (higher canopy, higher level of clonality, and heavier seeds) compared to the plain grasslands. North-facing slopes with mild environmental conditions were characterized by perennial species with light seeds, short flowering period, and a high proportion of dwarf shrubs sharply contrasted from the plain grasslands and from the south-facing slopes and mound tops with harsh environmental conditions. Patterns predicted by CWMs and abundance models differed in the case of certain traits (perenniality, canopy height, and leaf dry matter content), suggesting that environmental factors do not necessarily affect trait optima directly, but influence them indirectly through correlating traits. Due to the large relative differences in environmental parameters, contrasts in trait composition among microsites were mostly consistent and independent from the macroclimate. Mounds with high environmental heterogeneity can considerably increase variability in plant functional traits and ecological strategies at the site and landscape levels. The large trait variation on topographically heterogeneous landscape features can increase community resilience against climate change or stochastic disturbances, which underlines their conservation importance.

PhD defence of Katalin Lukács

Congratulations to Kata Lukács, who last week defended her PhD thesis entitled "The mechanism and ecological importance of human-vectored seed dispersal" with summa cum laude. We wish you all the best for the future and continue happy sciencing :)

Kata's PhD topic was the ecological significance of human-vectored seed dispersal. This is a very interesting, new, diverse and human-centered topic :) Kata has carried out her doctoral research with maximum dedication, enthusiasm, and precision.

Start of our first experiment related to human-vectored dispersal in 2017...

And continuation of the same experiment a few years later :)

The dissertation is based on the following articles:

Lukács, K., Tóth, Á., Kiss, R., Deák, B., Rádai, Z., Tóth, K., Kelemen, A., Bátori, Z., Hábenczyus, A.A., Tölgyesi, C., Miglécz, T., Godó, L., Valkó, O. (2024). The ecological footprint of outdoor activities: Factors affecting human-vectored seed dispersal on clothing. Science of the Total Environment 906: 167675. PDF

Valkó, O., Lukács, K., Deák, B., Kiss, R., Miglécz, T., Tóth, K., Tóth, Á., Godó, L., Radócz, S., Sonkoly, J., Kelemen, A. & Tóthmérész, B. (2020). Laundry washing increases dispersal efficiency of cloth-dispersed propagules. NeoBiota, 61, 1. PDF

Lukács, K., & Valkó, O. (2021). Human-vectored seed dispersal as a threat to protected areas: Prevention, mitigation and policy. Global Ecology and Conservation, 31, e01851. PDF

Lukács, K., & Valkó, O. (2022). Magterjedés az emberi ruházaton: megelőzési és védekezési lehetőségek. Természetvédelmi Közlemények, 28, 74–85. [in Hungarian] PDF

If you are interested in the topic, read the doctoral thesis, available here (in Hungarian and English). 

.. or the slightly shorter summary of the doctoral thesis, below:

The doctoral dissertation consists of three chapters aiming to provide an in-depth understanding of epianthropochory and to investigate further details of this process. In the first chapter, we collected data in a multi-site field experiment in three Central-European countries. We collected the diaspores (seeds, fruits) from 88 volunteer participant’s shoes and socks and we studied the effects of landscape-, vector- and plant characteristics. In total of 251 samples (and 2008 subsamples) we identified 229 plant species and we were the first to report the ability for cloth-dispersal in case of 137 species. Most of the identified species were weeds and disturbance tolerant species, which might cause serious environmental problems worldwide. We have shown that site characteristics and vector characteristics strongly influence the human-vectored seed dispersal (HVD) on clothing. In the second chapter, we tested the germination potential after the laundry washing in case of diaspores of 18 plant species. In addition, the adhesion potential of the diaspores was tested on three different clothing and fabric types (blue jeans, polar sweater and cotton socks) before and after the laundry washing. Our results show that washing temperature was the most significant factor affecting germination. Gentle washing at 30 C did not affect the germination potential, while intensive washing (60 C) decreased the seedling number in half of the species. Washing at 60 C desynchronized the germination of eight species. In desynchronized germination, diaspores start germination at different times. If germination is desynchronized, there is a higher chance some diaspores will germinate in a perfect time and establish in a new environment. We found that the lowest proportion of diaspores remained attached on blue jeans. Some of the diaspores may remain on clothing after the laundry washing and may even spread over long distances. In the third study, our aim was to collect biosecurity measures related to HVD on clothing. The biological measures were grouped according to the categories in force: information, self-regulation, legislation, quarantine measures, monitoring, interception and visitor management. Based on the literature, we added useful suggestions to guide to development of future directives.