Biology subjects

Marton, Z.

Publications and source records attributed to Marton, Z..

8 recordsLinked to original sources

bioRxiv2026

Pond age and agricultural land cover influence the occurrence of Anopheles maculipennis in garden ponds in Hungary

Garden ponds are important elements of urban landscapes and provide numerous ecosystem services, but they may also support mosquito populations that can act as vectors of pathogens. However, mosquito occurrence in garden ponds has so far received limited attention. We engaged citizen scientists to provide data on their garden ponds and collect water samples for eDNA analysis to assess mosquito occurrence in 319 garden ponds across Hungary, with special focus on Anopheles maculipennis, a potential malaria-vector species. We tested the effects of land cover, local pond management activities and environmental factors on the probability of An. maculipennis occurrence in garden ponds. Overall mosquito occurrence was relatively low, with mosquitoes detected in 59 ponds (18%) and An. maculipennis detected in 46 ponds (14%). Agricultural land cover and pond age were associated with the occurrence of An. maculipennis in garden ponds. A higher percentage of agricultural land cover within 1000 m of garden ponds increased the probability of An. maculipennis occurrence, while occurrence was higher in newly created ponds ([≤] 2 years). Our results suggest that landscape context is more important than local pond characteristics in determining the occurrence of An. maculipennis in garden ponds. This study contributes to a better understanding of the landscape context in which a potential malaria-vector species occurs in urban and peri-urban environments and highlights the value of citizen science for large-scale data collection from privately owned ponds that are otherwise inaccessible to researchers.

ecology↗

bioRxiv2024

Connectivity loss in experimental pond networks leads to biodiversity loss in microbial communities

Habitat fragmentation is among the most important global threats to biodiversity, however, the direct effects of its components including connectivity loss are still lesser known. Our understanding of these drivers is especially limited in microbial communities. Here, by conducting a four-month outdoor experiment with artificial pond (mesocosm) metacommunities, we studied the effects of connectivity loss on planktonic prokaryote and microeukaryote communities. Connectivity loss was simulated by stopping the dispersal among local habitats while keeping the habitat amount constant and the abiotic environment homogeneous. We found that connectivity loss led to higher levels of extinction and a decrease in both local and regional diversity in microeukaryotes. In contrast, diversity patterns of prokaryotes remained largely unaffected, with some indications of extinction debt. Connectivity loss also led to lower evenness in microeukaryotes, likely through changes in biotic interactions with zooplankton grazers. Our results imply that connectivity loss can directly translate into species losses in communities and highlight the importance of conserving habitat networks with sufficient dispersal among local habitats.

ecology↗

bioRxiv2024

A matter of salt: global assessment of the effect of salt ionic composition as a driver of aquatic bacterial diversity

While the strong general effects of salinity on microbial diversity are well-known and described for marine and freshwater habitats, the impact of the specific composition of major inorganic ions remains largely unexplored. In this study, we assess how microbial community structure in inland saline aquatic habitats is influenced by ionic composition as compared to salinity, spatial factors, and other environmental parameters. We collected and analysed 16S rRNA gene V4 and V3-V4 amplicon datasets from freshwater to hypersaline aquatic environments worldwide (in total 375 samples from 130 lakes). With an emphasis on saline inland waters characterised by highly variable ionic composition, we demonstrated that the ionic composition of the major ions explained more variability in community composition than bulk salinity and that the geographic location of the sampling sites had only an ambiguous effect. We also identified the taxa contributing the most to the observed dissimilarity between communities from sites with different ionic composition and found mostly lineages known to be characteristic for a given habitat type, such as Actinobacteria acI in freshwater, Halomonadaceae in saline, or Nitriliruptorales in soda and soda-saline habitats. Many of these habitat type-specific indicator lineages were monophyletic, underpinning ionic composition as a crucial eco-evolutionary driver of aquatic microbial diversity.

microbiology↗

bioRxiv2023

Effects of urbanisation, habitat characteristics, and management on garden pond biodiversity: a citizen science approach

The rapid expansion of urban areas often leads to degradation, fragmentation, and loss of natural habitats, threatening biodiversity. While urban ponds might contribute substantially to the biodiversity of urban blue-green infrastructure, the role of garden ponds is still largely unkown. We lack a comprehensive understanding of how local habitat features, different forms of management, and urbanisation might impact the biodiversity of these habitats. This study aimed to reveal the importance of garden ponds via a country-wide online citizen science survey in Hungary, Central Europe. Data from over 800 pond owners revealed the occurrence and local frequency of various native animal taxa (amphibians, odonates, and birds), and introduced animals (e.g., fish). We collected data about pond features and management practices. We tested the effect of pond features, pond management, and landscape-level drivers (urbanisation, surrounding wetland coverage) on the presence of conspicuous animal taxa (adult amphibians and tadpoles, birds, odonates) to identify the potential drivers of the biodiversity of garden ponds. Key pond features including pond age, area, aquatic and shoreline vegetation were the most important factors, while algaecide addition was the most influential management practice negatively affecting amphibian presence. Urbanisation negatively affected the presence of adult amphibians and their tadpoles, but it was not associated negatively with the presence of odonates and birds. Our results indicate the high potential to utilise garden ponds as urban habitats surveyed with the help of the public. Developing effective urban biodiversity monitoring and conservation strategies are necessary for a better functioning blue-green infrastructure. The high level of engagement of pond owners, as in our survey, can create valuable data for achieving these aims.

ecology↗

bioRxiv2023

Patterns and correlates in the distribution, design and management of garden ponds along an urban-rural gradient

Urbanisation results in the loss and alteration of natural wetlands and ponds. However, garden ponds in cities and towns can act as rich reservoirs of aquatic biodiversity and stepping stones for dispersal. Homeowners with a range of different motivations, including biodiversity values, install garden ponds. Here, our main aim was to study whether the design and management choices of garden pond owners was dependent on the location of ponds (capital city vs. countryside), when ponds were installed (pond age), or whether fish were introduced. We surveyed 834 garden pond owners across Hungary using a citizen science questionnaire, asking questions on pond size, location, construction date and materials, vegetation structure, introduction of fish and management practices. From 753 validated responses, we found that the introduction of fish into ponds and high urbanisation were strongly associated with local features and management practices, especially large ponds with a water circulation feature, irrespective of pond age. A typical garden pond in Hungary is [~]20 m2, <10 years old, made of rubber (PVC) lining, contains fish, aquatic vegetation and circulating water, and is actively managed. There was a spatial separation of ponds based on local features between ponds in the capital city (Budapest) and elsewhere. These findings suggest that garden pond owners in cities are likely to make different choices in pond design and management compared to owners in regional areas. Our results also suggest that pond owners may primarily select management practices to improve habitat quality for ornamental fish. Our findings have important implications for maintaining aquatic biodiversity in urban areas, where garden ponds may be the only aquatic habitat available. RESEARCH HIGHLIGHTSO_LIHungarian garden ponds [≤] 200 m2 occur in both large cities and small villages C_LIO_LIMost garden ponds we sampled in Hungary were built in the last decade C_LIO_LIPond design and management differs between Budapest and regional areas C_LIO_LIPond design and management practices are influenced by ornamental fish stocking C_LIO_LIPond owners frequently drain ponds to remove sediment and leaves and use algaecides C_LI

ecology↗

bioRxiv2023

Contrasting Response of Microeukaryotic and Bacterial Communities to the Interplay of Seasonality and Stochastic Events in Shallow Soda Lakes

Seasonal environmental variation is a leading driver of microbial planktonic community assembly and interactions. Yet, unexpected departures from general seasonal successional trends are often reported. To understand the role of local stochastic events in modifying seasonal succession, we sampled fortnightly throughout three seasons (spring, summer, and autumn) five nearby shallow soda lakes exposed to the same seasonal meteorological changes. We characterised their microeukaryotic and bacterial communities by 18S and 16S rRNA gene sequencing, respectively. Biological interactions were inferred by the analyses of synchronous and time-shifted interaction networks, and the keystone taxa were topologically identified. The pans showed similar succession patterns during the study period with spring being characterised by high relevance of trophic interactions and certain level of community stability followed by a more dynamic and variable summer-autumn period both in respect of community composition and microbial interactions. Adaptation to general seasonal changes happened through the abundant shared core microbiome of the pans. However, stochastic events such as desiccation and cyanobacterial blooms disrupted common network attributes and introduced shifts from the prevalent seasonal trajectory. These were more pronounced for microeukaryotes than for bacteria which was reflected in increased turnover and contribution of non-core microeukaryotes. Our results demonstrated that despite being extreme and highly variable habitats, shallow soda lakes exhibit certain similarities in the seasonality of their planktonic communities, yet random stochastic events such as droughts can instigate substantial deviations from prevalent trends for the microeukaryotic but not bacterial communities.

microbiology↗

bioRxiv2022

Environmental changes associated with drying climate are expected to affect functional groups of pro- and microeukaryotes differently in temporary saline waters

Temporary ponds are among the most sensitive aquatic habitats to climate change. Their microbial communities have crucial roles in food webs and biogeochemical cycling, yet how their communities are assembled along environmental gradients is still understudied. This study aimed to reveal the environmental drivers of diversity (OTU-based richness, evenness, and phylogenetic diversity) and community composition from a network of saline temporary ponds, soda pans, in two consecutive spring seasons characterized by contrasting weather conditions. We used DNA-based molecular methods to investigate microbial community composition. We tested the effect of environmental variables on the diversity of prokaryotic (bacteria, cyanobacteria) and microeukaryotic functional groups (ciliates, heterotrophic flagellates and nanoflagellates, fungi, phytoplankton) within and across the years. Conductivity and the concentration of total suspended solids and phosphorus were the most important environmental variables affecting diversity patterns in all functional groups. Environmental conditions were harsher and they also had a stronger impact on community composition in the dry spring. Our results imply that these conditions, which are becoming more frequent with climate change, have a negative effect on microbial diversity in temporary saline ponds. This eventually might translate into community-level shifts across trophic groups with changing local conditions with implications for ecosystem functioning.

ecology↗

bioRxiv2021

Microbial stowaways - waterbirds as dispersal vectors of aquatic pro- and microeukaryotic communities

AimWaterbirds are important dispersal vectors of multicellular organisms such as macrophytes, aquatic macroinvertebrates, and zooplankton. However, no study to date has focused on their potential role in dispersing aquatic microbial communities (i.a., bacteria, algae, protozoa). Here, we explicitly studied passive transport (endozoochory) of prokaryotes and unicellular microeukaryotes by waterbirds based on DNA metabarcoding approaches. By directly comparing the dispersed set of organisms to the source pool of a natural metacommunity, we aimed for a realistic estimate of the overall importance of waterbird zoochory for natural microbial communities. LocationShallow saline temporary ponds (soda pans) in the cross-border region of Austria and Hungary. TaxonProkaryotes and unicellular microeukaryotes. MethodsIn 2017 and 2018, water samples from 25 natural aquatic habitats along with fresh droppings of the dominant greylag goose (Anser anser) and four other waterbird species were collected in a habitat network of temporary ponds. Their prokaryotic and microeukaryotic communities were identified via 16S and 18S rRNA gene amplicon sequencing. Sequence reads were analysed using mothur. After quality filtering of the reads, pro- and microeukaryotic amplicon sequencing variant (ASV) compositions were compared between the aquatic and dropping samples, across years and waterbird species. ResultsWe found that 28% of the dominant aquatic prokaryotic and 19% of the microeukaryotic ASVs were transported by A. anser. ASV richness in A. anser droppings was lower, but compositional variation was higher compared to the aquatic communities, probably resulting from stochastic pick-up of microbes from multiple aquatic habitats. We furthermore found that the composition of prokaryotic ASVs in bird droppings were different among the two years and reflected the actual aquatic communities. The dispersed set of microbes were largely similar among the different waterbird species except for the planktivore filter-feeder northern shoveler (Spatula clypeata) which was outstanding by dispersing a more species-rich subset of microeukaryotes than shorebirds or geese. Main conclusionsBy using a combined amplicon-sequencing approach to characterize microorganisms in waterbird droppings and in the associated environment, our study provides strong evidence for endozoochory of natural aquatic microorganism communities. These results imply that waterbirds may be crucial in maintaining ecological connectivity between discrete aquatic habitats at the level of microbial communities.

ecology↗