Waterbird guilds predict environmental attributes of aquatic ecosystems

Alkaline soda pans of Hungary are special representatives of inland saline waters in the interior of the continents. The largest number of soda pans in Eurasia is found in the Carpathian Basin, and these lakes are also important resting and feeding areas for migratory birds in the European-African bird migration routes. Evidence is mounting that globally, aquatic habitats and waterbird populations are being rapidly declined by the land-use and land cover changes of recent decades (drainage, run-off), and climate change: rising temperatures and changing rainfall patterns. Waterbird populations play an important role in trophic- and host-parasite networks, and their cultural and recreational role is also important, but as bird populations and habitats decline, these ecological services are also declining.

Emil Boros, Senior Research Fellow at the Centre for Ecological Research, Institute of Aquatic Ecology, has been studying the interaction between waterbird populations and soda pans for many years. In an earlier publication in the Science of the Total Environment they found that waterbirds contribute high phosphorus loading (P) to the shallow saline lakes through their droppings, i.e. birds act as vectors of external phosphorus sources, a process called guanotrophication (bird-induced nutrient enrichment). Waterbirds, such as large-bodied herbivores (goose and duck species) and medium-bodied omnivores (e.g. gulls) have been shown to be 64% responsible for the extremely high phosphorus content of natural soda pans. However, it was also found that, the hypertrophic state of water was in contradiction with the limited primary production of natural soda pans due to the characteristics of the lakes: shallow water depth, high alkalinity (PH ≥ 9), and intermittent hydrological cycle.

Lake Balkhash

In a further investigation about the interaction between inland saline aquatic ecosystems and waterbirds the aim was to show whether the ecological/trophic attributes of saline water bodies could be predicted on multi spatial-scales by different groups (guilds) of waterbirds. Also published in the prestigious journal Science of the Total Environment, Emil Boros and colleagues studied a vast area of 1700 km by 1000 km at different spatial scales in the steppe and semi-desert region of Kazakhstan, where 63 sample area were selected. Nearly 100 waterbird species occurred in the sample areas and were classified into three groups according to their role in nutrient cycling and nutrient turnover: net-importers (large herbivores e.g. geese, cranes), importer-exporters (omnivorous ducks and gulls) and net-exporters (various herbi-, omni- and piscivorous species), based on Boros’s classification method. The abundance, biomass and diversity of these bird groups (guilds) were compared with the attributes of the inland waters on multi spatial scales e.g. water depth, chlorophyll content, and at larger spatial scales, with the land cover data found in the 1 and 10 km radius around the ponds e.g. grassland or agricultural land.

Their results showed that the occurrence of the above waterbird groups was strongly correlated with the attributes of the saline aquatic ecosystems on multi-spatial scale. Water cover and salinity are the main attributes predicting of the type of bird group that occurs in a given environment. The importer-exporter and net exporter bird groups showed positive correlations with productivity metrics and water depth of the waters, while the importers were predicted by the surrounding pond environment e.g. grassland.
The practical significance of this study is that it quantifies this ecosystem services provided by waterbirds, their role in nutrient cycling, which is essential for systematic monitoring and habitat management. The classification system and methodology described in this study can be used to estimate certain environmental attributes of inland water bodies for large geographic regions by counting waterbird populations. In the future, this will provide an opportunity to use birds to estimate ecosystem function and services of aquatic systems, which in turn will require further methodological studies.


Emil Boros, Zarina Inelova, Zsuzsanna Lánczos, Zsolt Végvári: Waterbird guilds predict environmental attributes of inland saline aquatic ecosystems on multi-spatial scales,
Science of the Total Environment, Volume 855, 2023.

Emil Boros, Anita Takács, Péter Dobosy, Lajos Vörös: Extreme guanotrophication by phosphorus in contradiction with the productivity of alkaline soda pan ecosystems,
Science of the Total Environment, Volume 793, 2021.

Photos: Emil Boros – Red-necked Phalarope and Lake Balkas


Inaugural lecture by András Báldi at the Hungarian Academy of Sciences

ANDRÁS BÁLDI, Corresponding Member of the Hungarian Academy of Sciences, Research Professor at the Centre for Ecological Research, held his inaugural lecture on 14 February 2023 in the Great Hall of the Hungarian Academy of Sciences.
Title: Biodiversity and ecosystem services: from fieldwork to policy

Biodiversity has declined over the past decades. Recognition and understanding the patterns and processes of ecosystems and thus halting their degradation is essential for human-wellbeing. One of the main reason of biodiversity loss is the transformation of original natural habitats leaving only small isolated patches of remnants in human-dominated landscapes. These patches of habitats are subject to the species-area relationship, one of the few laws of ecology. The proportion of interior and edge habitats is also decreasing. All these are reflected in the presence of species and individuals, but natural patterns and processes can be affected by human interference. Patches of natural habitats are surrounded by human-dominated land, mostly agricultural land which may still have significant biodiversity values. Fundamental questions remain to be answered, such as what is the impact of farming and landscape structure on biodiversity and the ecosystem services? Research results ensure essential information to nature-friendly management practices in order to help effective conservation of biodiversity. The next step towards practice is to integrate research results into policy. This step involves a number of processes and institutions in which researcher’s participation is a key.
András Báldi presented the existence of human influence overriding the species-area relationship, and the positive but species-specific effect of habitat edges on bird abundance and the negative effect of habitat edges on the survival of nestlings. Over many years, the biodiversity of many agricultural habitats has been studied, including plants, grasshoppers and related insects , ground beetles, bugs, cicadas, bees, wasps, birds, and has shown that the species richness of the natural habitat in Hungary is significantly higher than in other intensively farmed countries. To conserve this richness, context-dependent management – e.g. local habitat, landscape, taxon – is required. In their landscape-scale experiments launched in recent years, the most effective management options are investigated by creating wildflower plots and overplanting fallow land, from which both the farmer and biodiversity can benefit. Finally, he outlined how research results can be translated into policy and decision-making and what is the role of researchers in it at international level.
Photo: Tamás Szigeti


András Báldi was elected Head of the Section of Organismic and Evolutionary Biology of Academia Europaea

András Báldi, research professor of the Centre for Ecological Research and a corresponding member of the Hungarian Academy of Sciences, has been elected Head of the Organismic and Evolutionary Biology Section of the Life Sciences Division of the Academia Europaea, a leading European research community.
Founded in 1988, the Academia Europaea (AE) (European Academy of Sciences) has around 5,000 members, including 83 Nobel laureates. The AE’s objectives include promoting and disseminating the results of European research, fostering interdisciplinary and international research cooperation, and raising public awareness of scientific results.
“The Academia Europaea resembles the academies of the old days, the “learned societies”. It has a staff of just a few people, so every activity initiated and carried out by its members. A series of seminars, conferences and peer-reviewed papers are indicative of this. The Section of Organismic and Evolutionary Biology is one of the smallest, with 139 members. However, it has a total of eight distinguished Hungarian members from several institutions in the country” – told András Báldi to
András Báldi’s term of office is three years from 1 January 2023. He said that his election was partly due to his experience in leading international societies and partly to the fact that has practice in mediating between science and policy. The latter is also important because one of the main objectives of the section is to provide useful advice to EU decision-makers.
“To this end, my aim is to complement the membership by involving European leaders in highlighted research field,” he said. “In addition to professional excellence, we also take into account the need to strike the right balance between gender, countries and disciplines. In other words, it is not mechanistically the science metrics that matter, but whether the candidate excels in their particular situation.”
András Báldi said there is a sense that climate change and the crisis of biodiversity loss are increasing the weight of ecology, both in scientific research and in international scientific organisations.
He cited as an example the fact that the Global Risks report for the World Economic Forum in Davos included climate change and biodiversity loss among the six environmental problems that are estimated to be the greatest threats over the next 10 years. “A working group on environmental sustainability has also been set up within Academia Europaea.”

Source: - Magyar akadémikus az Academia Europaea Organizmus- és Evolúcióbiológiai Szekciójának élén - 2023-01-24


Co-seeding grasses and forbs supports restoration of species-rich grasslands and improves weed control in ex-arable land

The members of the ‘Lendület’ Seed Ecology Research Group of the Centre of Ecological Research followed the vegetation dynamics of artificially created grassland patches for several years. The researchers found that in the course of grassland-restoration the efforts at the beginning pay off: the simultaneous sowing of grasses and forbs in fallow lands leads to the development of species-rich grassland communities and efficient weed control.
The aim of ecological restoration is to recreate something lost or deteriorated. Grassland restoration aims to recreate grassland ecosystems and communities. In many cases recreation of the original ecosystem is not a possibility, but restoration still can help to cover landscape scars created by human activities. Restored grasslands not only improve landscape aesthetics but offer many different ecosystem services as well (e.g., forage for the livestock, nectar for pollinators, effective carbon capture and storage, and soil erosion control).
When grassland restoration is done with seed sowing, the success of restoration depends on many factors, such as the identity of sown species, the timing of sowing, the quantity, quality and proportion of sown seeds. In the current study the researchers aimed to find the best timing to sow grasses and forbs to achieve the highest possible species richness, to enhance forb-establishment and to hamper weed encroachment.
„The matrix of the grasslands is composed by grasses. Previous works found that sowing grass seeds certainly results in a closed grass sward within a few years, and also hampers weed encroachment. That is why grass sowing is preferred in landscape-scale restoration works. But it also has its feedbacks: the new grassland will be species-poor, as the closed grass sward hampers the establishment of other grassland species.” – explained Réka Kiss, the first author of the manuscript published in the Nature- Scientific Reports.
To create species-rich grasslands the use of diverse forb seed mixtures is needed. However, the compilation or production of such seed mixtures requires more efforts (seeds of more species are needed in good quality and high quantity). Due to these reasons diverse seed mixture is less likely to be used in the early stages of restoration. In later stages, however, it will need more effort from the practitioners to secure the successful establishment of species.
„We were curious of the most suitable timing: If we want to sow both grasses and forbs in a fallow for a species rich grassland, which is the time-lag when with the least effort we can achieve the most?” – explained Réka Kiss – „At the beginning of the experiment we created 36 patches in a recently abandoned land. We sow exclusively grass seeds, exclusively diverse forb seed mixture (20 species) or both of them into the patches. When we combined the grass with the forb seed mixture we sown them simultaneously (at the same time), or the diverse seed mixture was sown with a delay of 1, 2 or 3 years.”
Following the development of the patches for several years the researchers found that the best results were achieved when seeds were sown simultaneously, without time-lag. In such patches the species richness of species was the highest, the weeds were less successful and the establishment success of sown forb species was the highest. This is the most cost-effective and most successful method among the studied sowing regimes. If simultaneous sowing is not a possibility, sowing forbs one year later than grasses is still effective. However, after one year the advantage received by grasses cannot be outcome by the forbs, their successful establishment in later stages can be promoted only by active interventions.

Source: - Co-seeding grasses and forbs supports restoration of species-rich grasslands and improves weed control in ex-arable land - 2022-12-08


Tamara Szentiványi wins AXA Fellowship

Tamara Szentiványi, a research fellow in the Evolutionary Ecology Research Group of the Centre for Ecological Research, has been awarded a two-year AXA Fellowship research grant.
Since its launch in 2008, the AXA Research Fund has supported transformative scientific research on major global risks and the dissemination of research results. The Fund supports projects in the fields of health, environment, new technologies and socio-economic issues. The AXA Research Fund’s Scientific Panel is currently supporting eight research projects in the Field of Climate Change and Health, including Dr. Tamara Szentiványi’s project on „Effects of climate change on the eco-epidemiology of zoonotic arbovirus infection in avian hosts”.
In her awarded research project, Dr. Tamara Szentiványi will analyse the current distribution and public health risk of avian arboviruses, which can spread zoonotic diseases, and improve current surveillance methods to monitor vector-borne diseases.