New review paper on the soil seed banks of drylands

Our latest article a review of the soil seed bank of drylans, has been published with the first authorship of Abdubakir Kushbokov.

Kushbokov, A., Deák, B., Valkó, O. (2025): Characteristics of soil seed bank in global drylands – A review. Arid Land Research and Management 39: https://doi.org/10.1080/15324982.2025.2467728 

The pdf of the article is available from the authors (please click here).

Drylands cover a large part of the Earth and are unique in terms of their biodiversity and the ecosystem services they provide. Understanding the characteristics and restoration potential of the soil seed bank is key to maintaining and restoring ecosystem biodiversity. In our review article, we looked at the characteristics of the soil seed bank in global drylands and analysed the key factors influencing seed bank density and composition, including soil and climatic characteristics, woody vegetation, topography, and grazing. In our article, we have shown that soil seedbank can contribute to some extent to the restoration of degraded dry habitats, but in many regions and in highly degraded and overgrazed environments, the restoration potential of seedbank is limited.

Map showing the locations of the reviewed studies and the studied treatments.

Please see the abstract of the paper below.

Abstract

Drylands, covering 45.4% of the global land area, are vital ecosystems that support 38% of the world’s population and approximately 35% of global biodiversity. However, they face increasing threats from desertification, land degradation, and unsustainable management practices. Soil seed banks (SSBs) play a critical role in vegetation recovery, resilience, and biodiversity conservation in drylands. This review synthesizes evidence from 58 studies to evaluate the effects of grazing, topography, and woody plants on SSB dynamics and restoration potential. Grazing impacts on SSBs are highly variable, ranging from depletion under heavy grazing to enhanced seed density and diversity under moderate grazing or intermediate-term exclusion. Topographical features, such as dune tops and leeward slopes, and shrubs significantly influence SSB density and diversity by creating seed-rich microsites. While passive restoration using SSBs shows promise, especially in sandy grasslands, it is often slower than active interventions and limited by insufficient seed resources in severely degraded areas. The findings highlight the need for tailored grazing management and integrated restoration strategies to optimize the restoration potential of SSBs. Future research should address knowledge gaps related to underrepresented regions, deeper soil layers, long-term processes, and the combined effects of multiple drivers to enhance dryland ecosystem resilience and functionality.

A picture from our study site in the Kyzyl-Kum drylands, where we started investigating soil seed bank composition.

Effects of laundry washing on the germination of cloth-dispersed seeds: our new paper in Journal of Environmental Management

Our new paper by Katalin Lukács et al. has recently been published in Journal of Environmental Management.

The citation of the paper is:

Lukács, K., Kiss, R., Tóth, Á., Godó, L., Deák, B., Valkó, O. (2025): Effects of laundry washing on germination of cloth-dispersed seeds depends on washing intensity not on detergent type. Journal of Environmental Management 375: 124345. https://doi.org/10.1016/j.jenvman.2025.124345

It is an open access paper that can be freely downloaded from the journal's homepage (please click here).

In this study, we investigated a simple, everyday process - laundry washing. This seems a bit odd, why ecologists study this process - but our study revealed that indeed, it can have very interesting effects on the dispersal of plant species :)

What is the importance of our clothing in the dispersal of plant species? Unintentional human-vectored dispersal (HVD) is a special form of epizoochory, in which the seed dispersal vectors are humans, with seeds attaching to clothing or footwear during various outdoor activities. Due to the increasing human mobility, large quantities of seeds can be spread over long distances on a daily basis. It is important to emphasize, that, to date, mostly weeds and invasive species have been documented as capable of spreading on clothing. Despite HVD is part of everyday life, most people remain unaware of this phenomenon. In many cases, people do not pay attention to clean their clothes from seeds or may not even notice their presence. Unnoticed seeds on clothes can end up in washing machines regularly.

We designed a large experiment to study the effect of laundry washing on the germination potential of cloth-dispersed seeds, with particular attention to the effects of detergents and washing intensity. Since in our earlier study (Valkó et al. 2020 NeoBiota) we did not find a significant effect of detergent type, we sought to investigate this topic further to identify whether a specific detergent could significantly reduce the germination potential of cloth-dispersed seeds. To this end, we selected detergents based on their chemical composition, to represent the main types of detergents used in households (ranging from natural detergents to synthetic ones with varying concentrations of surfactants, enzymes, and soap). We aimed to cover the full spectrum of the detergent types and washing intensities most commonly used in households, and we had in total 21 treatment combinations.

The main idea of our experiment and the design of the treatments.

The findings show that most seeds remain viable after typical household washing, even at common temperatures and wide range of detergent types, highlighting a largely overlooked vector of plant dispersal. These results provided critical insights into the unintentional spread of plant species through human-vectored dispersal via clothing, a pathway that has received limited attention so far. Since most of the plants that are capable of cloth-dispersal are weeds and invasive species, the results have important implications for management. We emphasize the need for targeted biosecurity measures, especially among those working outdoors, to mitigate the spread of invasive species. The results also offer actionable strategies for environmental management by integrating behavioral changes and public awareness to reduce the environmental impact of human-vectored dispersal. According to our questionnaire survey, raising awareness is especially important for nature conservation professionals who are among the most important potential vectors.

Abstract

Unintentional human-vectored seed dispersal (HVD) occurs when the seed dispersal vectors are humans, and the seeds are attached to clothing or footwear during various outdoor activities. Since most plant species spread by HVD are invasives or weeds, the process can have globally relevant adverse environmental effects due to the growing global tourism industry. Here we evaluated whether the germination capacity of seeds can be reduced by laundry washing treatments used in households, in order to decrease the chance of unintended dispersal of plant species by clothing. We experimentally tested the effects of seven types of detergents with different chemical composition and three washing intensities in a full factorial design on the germination capacity of 18 plant species. Washing at high intensity (60 0C) significantly decreased the germination capacity in 15 species, probably due to high temperatures and longer exposure times. Washing at low (30 0C) and medium intensities (40 0C) had no effect. Detergent type affected the germination capacity of only three species. The findings underscore the importance of laundry washing in seed dispersal, since the low and medium washing intensities and detergent types that are commonly used in households do not decrease the germination capacity of the cloth-dispersed seeds. We urge addressing the spread of HVD-dispersed seeds through combined biosecurity measures. Self-regulation, such as removing of seeds from clothes and disposing them properly, is crucial. Informing outdoor workers, who play the largest role in HVD, can encourage small behavioural changes to decrease the adverse effects of this process.

The graphical summary of the study in the graphical abstract.

Homage to kurgans - A conference celebrating the past 30 years of kurgan research and protection in Hungary

A very inspiring and successful conference entitled "Protecting the kurgans '30" was organised by the Government Office of Békés County, the Hungarian University of Agriculture and Life Sciences and the Körös-Maros National Park Directorate in Békéscsaba on 21 November 2024. The occasion of the event was that 30 years ago, in the same place, a professional conference on the protection of the kurgans was held, which drew the attention of nature conservation to these special landmarks. The 1994 event was a milestone in the conservation of the mounds, so the organisers of the conference, in celebrating this fine anniversary, have created an opportunity to look back in 2024 on the achievements, successes and experiences of the past 30 years of kurgan research and protection in Hungary. Kurgans are ancient millennia-old burial mounds characteristic of the Eurasian steppe and forest steppe zone, that have outstanding historical, cultural, and nature conservational importance. For more information on these special landmarks, please read our earlier blog posts (e.g. here, here, and here) and scientific publications.

News about the conference in 1994 on the pages of Békés County Days (Békés Megyei Nap) magazine.

It was so nice to hear the thoughts and the presentations of the speakers. It was good to see and hear that the conservation of kurgans is on the right track in Hungary, and that the natural condition of the mounds has generally improved in recent decades, thanks to the joined efforts of conservationists, government, farmers, and researchers. The contributions and presentations highlighted the most important achievements and experiences of 30 years of kurgan conservation and research in Hungary. It was a great honour for us that our research group was represented at the conference with two presentations:

Ádám Bede: The main results of the landscape archaeological survey of the kurgans in the Maros-Körös river basin

Balázs Deák, Orsolya Valkó: Natural values of mounds in agricultural landscapes

In addition to the lectures, visitors were also able to view Ádám Bede's exhibition about kurgans.

Ádám Bede talking about the landscape archaeological importance of kurgans.

Balázs Deák talking about the importance of kurgans in nature conservation.

Many thanks to the Organizers, especially Dr. Attila Rákóczi, Director General of the Békés County Government Office for making this inspiring event possible! We hope that there will be many more such events in the future, where professionals who love and know the Hungarian kurgans can meet and present the values of the mounds and the importance of their protection to the public. It is very important that as many people as possible learn about the historical heritage and the conservation importance of these millennia-old mounds, because as Dr. András Rácz, State Secretary emphasized at the conference, "No one will protect what he is not interested in, and no one will be interested in what he has never experienced." (David Attenborough) 

The iconic Gödény-halom (Pelican-mound) near Békésszentandrás: the largest kurgan in Hungary.

The press release about the conference can be read here (in Hungarian).

Our new paper is published about the effects of steppe mice on the vegetation of agroecosystems

Our new paper by Laura Godó et al. has recently been published in Agriculture, Ecosystems and Environment about the effect of mound-building and caching activities of the steppe mouse.

Reference

Godó, L., Valkó, O., Borza, S., Ferencz, A., Kiss, R., Lukács, K., Deák, B. (2024) Effects of mound building and caching by steppe mouse (Mus spicilegus Petényi) on the vegetation in agroecosystems. Agriculture, Ecosystems and Environment 379: 109359. https://doi.org/10.1016/j.agee.2024.109359.

The paper is open access and can be downloaded from here.

To analyse the complex effects of caching rodents on agroecosystems, we selected the steppe mouse (Mus spicilegus Petényi, 1882), a small outdoor mouse, as a model species. It is a common herbivorous rodent inhabiting grasslands and agroecosystems from eastern Austria to western Russia. Its most well-known and spectacular habitat transformation effect is mound building: in autumn, a group of mice gather and build a mound above their burrow that provides protection against harsh environmental conditions and weather elements during the winter period. The mound consists of a thick layer of piled up inflorescences, fruits, and spikes covered by shallow bare soil layer. Therefore, these mounds are very interesting objects for vegetation dynamics: they contain huge amount of seeds, and they provide small distinct patches for plant establishment.

Our study sites in East Hungary (A), and pictures of a steppe mouse mound (B) and the studied agroecosystems: old-fields (C), alfalfa fields (D) and annual crop fields (E).

Our findings suggest that small-scale disturbances, like mound-building by the steppe mouse, contribute to maintaining plant diversity in otherwise uniform agroecosystems. The mounds provide low-competition sites with unique resources, creating small vegetation patches that differ from surrounding areas. The steppe mouse may act as a "facultative engineer" species, influencing vegetation based on habitat type. However, the mounds are often short-lived due to agricultural activity, leading to a constantly shifting pattern of mound sites, which temporarily facilitate plant establishment.

Seed analysis of the mouse's caches showed a preference for a few weed species, but only a few of these appeared in the vegetation on mounds. This finding suggests that while mounds provide good conditions for cached weeds, they don’t result in significant weed growth, which may help change farmers' perceptions of these rodents as pests. As a common species adapted to disturbed habitats and expanding across Europe due to milder winters, the steppe mouse may increasingly affect agroecosystem structure and function in the region.

Abstract

Several rodent species are considered ecosystem engineers. They exert profound changes in agroecosystems by disturbing the soil during their activities. The steppe mouse (Mus spicilegus) inhabits various agroecosystems and constructs conspicuous mounds for overwintering using piled up plant material and soil. These mounds are widespread in many agroecosystems and may significantly affect the vegetation. In our study, we evaluated the effect of mound building activity of the steppe mouse on the vegetation of agroecosystems in Hungary. We sampled the cache content of 90 mounds in total located in old fields, alfalfa fields, and annual crop fields, and surveyed the aboveground vegetation of the mounds and their surrounding undisturbed matrix in 39 paired plots. Mice cached large amounts of seeds belonging mostly to weeds. In total we found 50,413 germinable seeds of 30 species in the cache content samples. However, the mound vegetation and the cache shared only a few species, suggesting that seeds cached by the mice do not contribute to the regenerating vegetation on the mounds. Soil disturbance by mice created distinct vegetation patches with species composition and structure different from the neighbouring undisturbed matrix. Early secondary successional vegetation patches on mounds introduced small-scale heterogeneity into the homogenous agricultural landscape, increased plant diversity and provided distinct flower resources for pollinators. The detected differences in the aboveground vegetation between the mound and the matrix in the studied habitats suggest that the steppe mouse acts as a facultative engineer species in agroecosystems.

New paper about the population dynamics of an endangered geophyte, Colchicum bulbocodium

Our new paper by Réka Kiss et al. has been published today about the population dynamics of the spring meadow saffron in Scientific Reports.

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

Reference:

Kiss, R., Lukács, K., Godó, L., Tóth, Á., Miglécz, T., Szél, L., Demeter, L., Deák, B., Valkó, O. (2024) Understanding the effects of weather parameters on the population dynamics of an endangered geophyte supports monitoring efficiency. Scientific Reports 14: 25974. https://doi.org/10.1038/s41598-024-76942-5

This paper is a result of a six-year-long monitoring study and one of the final results of the PD OTKA project of Réka. The study of the population dynamics of this beautiful and endangered early-spring geophyte plant has important implications for species conservation. The species has an interesting life cycle and the different life stages have different detectability. The beautiful flowers are easy to detect, but the plants have low detectability in the leaf and capsule production stages, and it is completely hidden underground thereafter. Therefore it is crucial to understand the transitions between the stages to give reliable population estimations. In the paper we describe the transitions between these life stages and the effects of various climatic parameters on the population dynamics of Colchicum bulbocodium.

In early spring, the flowers are well visible.

And it is easy to find them :)

When only the leaves are visible, it is not easy to spot the plants.

Especially not in such kind of understorey vegetation...

Abstract

Due to their complex life cycles geophytes are often neglected in conservation programs, despite theyare important elements of early spring communities. Their life cycle is strongly affected by weatherparameters, i.e. temperature, precipitation, and light, but the effects of these parameters are oftencontradictory and show high intra-annual variability even within species. Deeper knowledge about theabiotic factors affecting the population dynamics of geophytes is needed to support the designationof effective conservation plans. We aimed to explore the link between weather parameters andpopulation dynamics of Colchicum bulbocodium, an endangered and strictly protected geophyte. Wemonitored three life cycle stages (flowering, growing, fruiting) of 1069 individuals in permanent plotsfor six consecutive years. Our results showed that life cycle of C. bulbocodium was strongly relatedto the actual weather parameters; the lagged effect of the previous year was weaker. Increasingtemperature and lack of cold periods had negative effect on all life stages. We highlighted thatpopulation estimation based on the number of flowering individuals in a single year can underestimatepopulation size by 40–83%. Monitoring in years following wet and cold springs and cold winters couldincrease the accuracy of population estimations of the flowering individuals.

Cultural and natural values of sacred sites - our new paper in Human Ecology

In our study recently published in Human Ecology, we aimed to explore the cultural values associated with ancient burial mounds, provide an overview of the landscape changes on and around the kurgans during the past 280 years, and explore the plant biodiversity of the kurgans. Based on our results, we evaluated factors that can support or endanger the grasslands on kurgans and assess whether there are synergies or trade-offs between cultural and natural values.

The citation of the paper:

Deák, B., Bede, Á., Süveges, K., Dózsai, J., Ormsby, A.A., Dixon, A., Valkó, O. (2024): Synergies and trade-offs between cultural and natural values of sacred sites – A case study of ancient burial mounds in Central Europe. Human Ecology https://doi.org/10.1007/s10745-024-00515-3

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

Kurgans, ancient burial mounds, hold significant cultural and spiritual value across the Eurasian steppes, reflecting a deep connection of local societies and these important landscape elements. These mounds, built by various steppe cultures like the Yamnaya, Sarmatians, Avars, and Hungarians, have served as cultural and spiritual landmarks for millennia. Their enduring cultural significance is evident through archaeological finds and the continued use of these sites for religious and communal activities.

Humka Kalvarija (‘Calvary Mound’; Kanjiža; Serbia)

Our study focusing on kurgans in Hungary, Romania, and Serbia reveals that these mounds are still regarded as sacred by local communities, who maintain graves and other spiritual objects on them. This cultural respect has helped preserve the kurgans, preventing destructive land use changes that could have altered their original state. In the past, kurgans also served practical purposes, such as acting as sentinel points, border markers, or flood refuges, further contributing to their preservation.

Despite significant landscape changes over the past three centuries, with much grassland converted to agricultural or urban use, the grasslands on kurgans have often remained intact. This preservation is likely due to the cultural importance of the kurgans, as land users consciously chose to protect these sites as part of their cultural heritage. Similar patterns of preservation due to cultural significance have been observed in other sacred sites around the world, such as sacred groves in India or land around monasteries in Italy. Kurgans are valuable for biodiversity, acting as refuges for grassland species that have become rare or endangered in surrounding landscapes. The relatively undisturbed state of these mounds, combined with their cultural significance, allows them to maintain high levels of plant species diversity. This makes kurgans important biodiversity hotspots in otherwise human-transformed landscapes. The microclimates created by the varying slopes and aspects of the kurgans contribute to this biodiversity by providing different habitats for various plant species.

Temető-halom (‘Cemetry Mound’, Iratoșu, Romania)

However, the maintenance of cultural values on kurgans can also lead to trade-offs. The construction of new religious and cultural structures can reduce the area of natural grassland, and the introduction of non-native or invasive species can threaten the existing biodiversity. In some cases, the lack of maintenance can lead to the accumulation of litter and an increased risk of fire, further endangering the natural values of the kurgans.

The study suggests that the cultural recognition of kurgans by local communities plays a crucial role in their preservation. This ‘bottom-up’ approach, driven by respect for historical and cultural heritage, can be more effective than formal protection measures. The findings highlight the importance of maintaining traditional cultural practices associated with kurgans to support the conservation of both their cultural and natural values. In conclusion, kurgans are essential biocultural hotspots that contribute to landscape-scale biodiversity conservation. Their preservation is vital not only for their cultural heritage but also for maintaining the ecological integrity of the landscapes they inhabit. By fostering a deeper understanding of the cultural and natural values associated with kurgans, we can better protect these ancient mounds and the biodiversity they support.

Humka Kalvarija (‘Calvary Mound’; Kanjiža; Serbia)

Abstract

In the Eurasian steppes, ancient burial mounds called ‘kurgans’ are among the most widespread manmade structures. These sacred sites hold cultural values and often provide safe havens for grassland-related plant species. We established links between kurgans' cultural and natural values through a comprehensive multi-layered evaluation of human and landscape history, cultural attributes, and botanical composition on selected mounds in Hungary, Romania, and Serbia. We evaluated factors that can support or endanger the grasslands on kurgans and assessed whether there are synergies or trade-offs between the presence of cultural and natural values. We found that kurgans act as cultural hotspots in transformed landscapes, and we found the following evidence for the synergies between cultural and natural values: i) Extensive land use and management connected to the cultural functions could considerably contribute to the preservation of grassland specialist plants on the mounds. ii) Over the past three centuries, most grasslands we studied were converted to cropland, but the cultural importance of the kurgans could hinder their destruction through ploughing or construction works. However, we also found that built cultural objects decreased the grassland cover area and supported the establishment and spread of several weedy and invasive species. Consequently, to preserve the valuable biocultural systems, it is essential to focus efforts on the maintenance of the already existing traditional cultural functions and not the establishment of new objects.

Our new paper about grassland restoration by topsoil removal and topsoil transfer - published in BMC Ecology and Evolution

Our latest paper about grassland restoration by topsoil removal and topsoil transfer  has been recently published in BMC Ecology and Evolution.

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

The citation of the paper:

Valkó, O., Kelemen, A., Kiss, O., Bátori, Z., Kiss, R., Deák, B. (2024): Grassland restoration on linear landscape elements – comparing the effects of topsoil removal and topsoil transfer. BMC Ecology and Evolution 24: 112. https://doi.org/10.1186/s12862-024-02299-y 

Here we compared the effectiveness of the two methods for the restoration of alkaline grasslands. We surveyed vegetation development after topsoil transfer and topsoil removal after the elimination of former linear landscape scars. Topsoil removal supported a rapid vegetation recovery and several rare halophyte species became established in the restored site. Topsoil transfer was less succesful and the developing vegetation was characterised by fewer target species and several weeds. Since these methods are rarely applied in Hungary, our results can provide new insights for the planning and implementation of restoration projects that involve the elimination of landscape scars.

This figure shows the initial conditions (in 2015): the positive landforms (embankments) and negative landforms (channels) that were eliminated in 2019. Below, you can see the recovering vegetation in the two sites in year 2 (2020).

Abstract

Artificial linear landscape elements, including roads, pipelines, and drainage channels, are main sources of global habitat fragmentation. Restoration of natural habitats on unused linear landscape elements can increase habitat quality and connectivity without interfering with agricultural or industrial development. Despite that topsoil removal and transfer are widely applied methods in restoration projects, up to our knowledge these were previously not compared in the same study system. To address this knowledge gap, we compared spontaneous vegetation recovery after the elimination of positive (embankments) and negative landscape scars (drainage channels) in lowland alkaline landscapes in South Hungary. The novelty of our study is that we compared the fine-scale and landscape-scale results of both methods. At the fine scale, we monitored the spontaneous vegetation development on the created open surfaces in the first, second and fourth year after restoration in 160 permanent plots per year. For characterizing the habitat changes on the landscape scale, we prepared habitat maps and assigned naturalness scores to each patch before and after the restoration activities. Both restoration methods resulted in a rapid vegetation recovery at the fine scale, progressing toward the reference state. In the topsoil removal treatment, a large part of the soil seed bank was removed; therefore, the colonization of the bare surface was a slower process. Seeds of halophytes, including the endemic and protected Suaeda pannonica, were probably present in the deeper soil layers, and these species became established in the restored surfaces, despite being absent in the surrounding vegetation. For restoring vegetation cover, topsoil transfer was a more rapid option; however, vegetation closure and competition by generalist species and weeds hampered the establishment of target species. The removal of the landscape scars by both methods made the sites accessible for grazing. At the landscape scale, the two methods had different effects: there was a slight increase in the habitat naturalness in the topsoil removal site, and a slight decrease in the topsoil transfer site because of weed encroachment. Spreading an upper layer of nutrient-poor soil with low amounts of weed seeds, direct propagule transfer, and targeted grazing regimes could enhance restoration success.