Ecological Implications Research Articles

Cross-scale Surface Kinetic Energy Transfer of Ocean Mesoscale Eddies in the Southern Ocean Revealed from the SWOT Mission

Abstract The cross-scale energy transfer among oceanic mesoscale eddies is crucial to shape their equilibrium state with important climate and ecological implications. The classical 2- and 3-dimensional turbulence theories predict an upscale and downscale energy transfer locally in spectral space (i.e., a cascade-like process), respectively. However, using unprecedented high-resolution measurements of sea level anomalies from the Surface Water and Ocean Topography (SWOT) mission combined with a high-resolution oceanic simulation, we demonstrate the coexistence of downscale and upscale transfers for surface mesoscale eddy kinetic energy (EKE) in the Southern Ocean. The latter dominates the former, leading to a net upscale surface EKE transfer. The downscale surface EKE transfer is generally local in the spectral space, achieved primarily via interactions of mesoscale eddies with horizontal scales differing by less than a factor of 2. In contrast, the upscale surface EKE transfer is less local, involving mesoscale eddies with larger horizontal scale separation. Accordingly, the upscale surface EKE transfer is severely underestimated in measurements from the last generation of satellite altimeters even at their well-resolved scales O(100 km). Our findings uncover the crucial contribution of EKE transfer by interactions among mesoscale eddies with evident scale differences, which is overlooked in the existing oceanography literature.

Establishment and parasitism levels of Ganaspis kimorum on Drosophila suzukii in Northeastern Italy: insights from a 4-yr release program.

The management of the invasive fruit fly Drosophila suzukii (Diptera: Drosophilidae) still relies on chemical control, despite concerns about pesticide resistance and environmental impact. Integrated pest management strategies are being explored, but current options remain limited and often insufficient. In invaded regions, local natural enemies are mostly generalist pupal parasitoids, which have proven inadequate for controlling this rapidly spreading pest. Conversely, in its native range, D. suzukii is host to more specialized larval parasitoids that may mitigate its impact on fruit crops. Extensive foreign exploration and risk assessments identified the larval endoparasitoid Ganaspis kimorum (Hymenoptera: Figitidae) as the most suitable candidate for classical biological control. In 2021, Italy launched a propagative biocontrol program utilizing a Japanese population of G. kimorum. Here, we present the results from the first 4 yr of releases conducted in Northeast Italy, where the parasitoid was released at 20 different locations. We provide an overview of the monitoring activities at these sites to determine whether G. kimorum has successfully established and to assess its parasitism levels on both the target pest and nontarget species. Results confirmed that G. kimorum is a specialist on D. suzukii and likely does not compete with local parasitoids for reproductive resources. Collected data also suggest that the parasitoid has become established in several locations, and it is gradually expanding its range from the initial release sites. Four years after the initial release of G. kimorum, the data gathered offers valuable insights into the efficacy and ecological implications of this biocontrol strategy.

Establishment and population expansion of the non‐native Azores chromis (Chromis limbata) in the subtropical southwestern Atlantic

Abstract This study documents new records and the spatial–temporal progression of the non‐native Azores chromis (Chromis limbata) in southeastern Brazil, particularly on the coast of São Paulo state. We report the first confirmed occurrence of C. limbata in the Alcatrazes Archipelago and document that, in recent years, its abundance has exceeded that of the native brown chromis (Azurina multilineata). These findings indicate potential shifts in the taxonomic composition of reef fish communities and highlights the importance of further research to understand the processes driving these patterns and their ecological implications.

Comprehensive Biometric Study on the Invasive Seaweed, Caulerpa mexicana, in the Aegean Sea

The present study investigates the occurrence and biometry of the invasive seaweed Caulerpa mexicana in the Gulf of İzmir, Aegean Sea, thereby highlighting its ecological implications in a region increasingly affected by biological invasions. The Mediterranean basin, especially the eastern and Aegean parts, is becoming a hotspot for non-native species, and the region may be a place of interest with the occurrence of the C. mexicana species. This research represents the first detailed assessment of its biometric characteristics in the Levant-Aegean Basin. The study's sampling was conducted from May to August 2024 at 321 stations along the Aegean coast, and C. mexicana was identified at only two specific sites. The species was found in shallow coastal waters at depths of 10 m and 15 m with densities of 630 shoots/m² and 469 shoots/m², respectively. Morphometric analysis revealed frond lengths ranging from 10 to 12.5 centimeters and widths from 7 to 9 millimeters, with a significant correlation between frond length and number of pinnae. Environmental parameters such as temperature, salinity, and dissolved oxygen were measured, providing a context for the species' habitat preferences. The findings underscore the invasive potential of C. mexicana and its capacity to perturb local marine ecosystems, highlighting the necessity for persistent monitoring and management strategies to mitigate its deleterious effects.

Phenolic Iron Complexes Protect Glacier Ice Algae (Zygnematophyceae) Against Excessive UV and VIS Irradiation

ABSTRACTMelting glacier surfaces are increasingly affected by blooms of psychrophilic microalgae, which darken the ice and lower its albedo, accelerating melting. These microalgae contain distinct vacuoles filled with brownish pigments that were earlier described as the unusual plant phenol purpurogallin. Recently, we discovered so far unreported, large amounts of iron dissolved in aqueous extracts of the glacier ice algae Ancylonema alaskanum. Since the vacuole content was very dark but the chromatographically isolated, aforementioned phenol was only yellowish, a putative complexation of iron with purpurogallin was assumed to be the reason. Application of several protocols, including Raman microscopy on both living cells and extracts, provided strong evidence that this microalga sequesters iron and forms organic metal complexes. Consequently, substantial amounts of so far uncharacterised Fe‐complexes of purpurogallin are inferred to be present in Ancylonema, and that putative polymerisation of this compound impeded an earlier analytical discovery. This finding holds significant ecological implications for cold regions. The pigmentation not only enhances the tolerance of glacier ice algae to excessive UV and visible radiation but also influences our current understanding of the biochemical iron cycle in cryosphere‐dominated polar and alpine regions. Further downstream consequences of this biological iron source remain to be elucidated.

Bacillus biofilm formation and niche adaptation shape long-distance transported dust microbial community

Long-distance microbial transport via dust events is projected to intensify globally. However, survival mechanisms of air- and dust-borne bacteria and their contribution to global processes remain poorly understood. In this study, we characterized Bacillus species from transitional season dust storms, previously identified as a significant component of the bioactive community of the dust microbiome. Our results demonstrated substantial growth and surface-associated biofilm formation diversification, linked to niche adaptation within heterogeneous dust particles. Most dust isolates formed biofilms while showing varying preferences for media composition under standard laboratory conditions, extreme temperatures, and low humidity. Sterile dust stimulated biofilm formation, growth, and matrix gene expression of B. subtilis, leading to robust biofilm development in key related dust isolates. This effect surpassed that of inorganic, synthetic dust, representing a role for organic substrates from decayed dust-community members. Overall, these findings offer direct evidence that biofilm formation serves as an adaptive mechanism in the unique habitat of dust particles, suggesting that niche adaptation may play a role in microbial survival across dust storms. These results hold significant implications for terrestrial and aquatic ecology and health, suggesting a pivotal process by which bacteria survive and evolve in this understudied habitat.

The role of plant host genetics in shaping the composition and functionality of rhizosphere microbiomes.

The plant microbiome comprises a wide range of microorganisms associated with different plant tissues. Over the past decades, significant research efforts have focused on understanding and harnessing the plant rhizosphere microbiome for optimal plant growth and health. However, while environmental factors are often the primary focus of these studies, the influence of plant genotype remains comparatively underexplored. In fact, the plant genotype influences a multitude of factors including root morphology and exudate composition, which play an integral role in shaping the rhizosphere niche. In this review, we discuss how alterations in plant host genetics could lead to differences in the assembly and diversity of the rhizosphere microbiome. Furthermore, we summarize current approaches to decipher complex plant traits and their ecological implications in host-microbiome systems and interactions.

First record of albinism in a Crab-eating Fox and review of anomalous coloration in Neotropical carnivores

Abstract Hypopigmentation can lead to albinism or leucism in animal pelage. This study presents the first documented case of albinism in the Crab-eating Fox (Cerdocyon thous) and explores anomalous coloration in Neotropical carnivores. An albino individual was observed in Nova Maringá, Mato Grosso, Brazil. A literature review identified 12 studies documenting 30 records of anomalous coloration across seven carnivore species, with the Tayra (Eira barbara) showing the highest occurrence (18 cases). Though rare, conditions like albinism and leucism can impact survival by reducing camouflage, communication, and reproduction, underscoring the need for further research into their causes and ecological implications.

Functional aspects of the headshield processes in ostracoderms

Abstract Ostracoderms, Paleozoic jawless stem-gnathostomes, are characterized by distinctive bony shields covering the front of their bodies. These headshields exhibit significant variations in morphology across species, boasting frontal, lateral, and dorsal processes. Ostracoderms represent pivotal intermediaries between modern jawless and jawed vertebrates, so understanding their biology and ecology is crucial for unraveling the selective pressures that shaped the early evolution and diversification of jawed vertebrates, which now dominate vertebrate diversity. This study employs virtual paleontology techniques and phylogenetic comparative methods to explore the hydrodynamic and ecological implications of these processes, focusing on pteraspidomorphs, the most diverse ostracoderm group. The analysis reveals widespread convergence in the arrangement and development of headshield processes. Lateral processes enhance hydrodynamic efficiency and generate lift, while combined lateral and dorsal processes provide stability in rolling, yawing, and pitching. Frontal processes reduce drag in many cases. These findings illuminate the enigmatic roles of ostracoderm headshields, showing how the dimensions and arrangement of their processes are biomechanically linked to a range of functions and ecological roles. Collectively, this highlights the intricate evolutionary pathways of lifestyles and ecologies within stem-gnathostomes, challenging the idea of a unidirectional trend toward more active lifestyles in vertebrate evolution and suggesting diverse ecological roles for ostracoderms.

Unraveling the Toxic Mechanisms of Microplastics in Aquatic Ecosystem: A Case Study on Vallisneria natans and Myriophyllum verticillatum.

Unraveling the Toxic Mechanisms of Microplastics in Aquatic Ecosystem: A Case Study on Vallisneria natans and Myriophyllum verticillatum.

How do I look when I'm infected? Morphometric changes in heads associated with Trypanosoma cruzi infection in flightless Triatominae.

How do I look when I'm infected? Morphometric changes in heads associated with Trypanosoma cruzi infection in flightless Triatominae.

Avulsion of the Nyabarongo River into Lake Rweru (Rwanda) Under Anthropic Pressure: Morpho-Sedimentary and Ecological Implications

Avulsion of the Nyabarongo River into Lake Rweru (Rwanda) Under Anthropic Pressure: Morpho-Sedimentary and Ecological Implications

Effects of microplastics on soil environment and land plant growth: a review.

Microplastics represent an emerging category of long-lasting environmental contaminants that exhibit detrimental impacts not only on marine ecosystems but also demonstrate extensive distribution within terrestrial environments. Currently, soil contamination by microplastics has become a pressing ecological issue, yet scientific investigations focusing on phytological systems remain comparatively limited when contrasted with environmental studies of soil matrices. These synthetic particulates exert dual-phase influences on vegetation development through both direct phytotoxic impacts and indirect mediation via modifying soil physicochemical characteristics. Following their translocation into terrestrial systems and progressive bioaccumulation within plant tissues, microplastics may undergo trophic transfer through food chains, ultimately posing potential health risks to human populations. This review systematically examines contemporary research progress regarding microplastic interactions with pedospheric environments, botanical organisms, and co-existing contaminants, with particular emphasis on their ecological implications for soil functionality and vascular plant physiology. Prospective research directions are outlined to establish theoretical foundations for subsequent investigations concerning microplastic biogeochemical cycles and their ecotoxicological consequences in terrestrial ecosystems.

Oxidative Stress, Phytochemical Screening, and Antioxidant Activity on Microalgae (Arthrospira platensis) After Exposure to Glyphosate and Microplastics

The knowledge about the potential toxic effects of microplastics (MPs) combined with herbicides at lower trophic levels is still largely unknown. The present study aimed to evaluate the potential toxic effects of polyethylene terephthalate (PET) and polyamide (PA), isolated or combined with the pesticide glyphosate (GLY), on the microalgae Arthrospira platensis. For this, microalgae were exposed to control, GLY (3 μg/L), PET (0.5 and 1 mg/L), PA (0.5 and 1 mg/L), and the respective mixtures of each MP with GLY, for 12 days. The photosynthetic pigment content, phytochemicals, antioxidants, and enzymatic activity were determined. Cell growth was significantly enhanced on day 4 in the GLY+PA1 group (~80%), compared to the control. At day 12, biomass was significantly higher in the GLY (~25%) and GLY+PET0.5 (~26%) groups relative to the control. Significant effects on the enzymatic and detoxification mechanisms were observed, including increased SOD (PET0.5, p = 0.011) and CarE (GLY, PA and GLY+PA, p < 0.01), and decreased GST in combined exposures, which support stress-induced enzymatic activation and adaptive biochemical responses. Significant effects on phytochemicals and antioxidant activity were also observed, with PET0.5 significantly reducing total carotenoids (~65%), and flavonoids (p < 0.001) and ortho-diphenols (p < 0.05) being decreased in all exposure groups, in comparison to the control group. The decrease in flavonoids and ortho-diphenols, important antioxidant molecules, suggests the depletion of these key compounds under stress. DPPH scavenging activity, a measure of antioxidant potential, was inhibited in the GLY+PA groups, indicating compromised antioxidant defense. Results confirmed that combined stressors elicit distinct and sometimes deleterious responses not predicted by single exposures. Our findings highlight that the combined exposure to glyphosate and MPs significantly disrupts antioxidant defenses and enzymatic activity in A. platensis, indicating potential risks to primary producers in aquatic ecosystems and underscoring the ecological implications of co-contaminant stressors. In fact, the results indicate that MPs can modify herbicide toxicity, posing enhanced risks to microalgal physiology and potentially affecting primary productivity and nutrient cycling in aquatic ecosystems. In turn, negative effects of MPs on microalgae can have serious consequences for food webs, food security, and ecological health.

The Larval and Adult Female Gut Microbiomes of Two Burying Beetles (Nicrophorus spp.) With Distinct Parental Care Traits.

Burying beetles (Nicrophorus spp.) exhibit parental care behaviours well-suited for studying gut microbiome and holobiont evolution. Theory predicts that differences in transmission can contribute to gut microbiome variations. We show that microbiome diversity estimates were comparable between reproductive females of common-garden-reared colonies of Nicrophorus marginatus (facultative parental care) and Nicrophorus orbicollis (obligate parental care). In contrast, the respective associated larvae of both species differed significantly. Furthermore, larval microbiomes clustered with respective adult female microbiomes but differed from each other. Fifteen bacterial families underscored differences in community composition between beetle species, with Wohlfahrtiimonadaceae significantly more abundant in N. orbicollis than N. marginatus. Results suggest that differences in parental transmission (trophallaxis) and larval acquisition of microbes possibly impact the parental-offspring gut microbiome dynamic. Close association of parental and larval microbiomes in the facultative parental care species is attributed to environmental acquisition from prepared carcasses and limited trophallaxis in larvae. However, the distinct larval and parental microbiomes in the obligate parental care species are attributed to the selective sorting of functionally relevant microbes from parents in larvae. Further examination of this genus's parental care behaviours and gut microbiome dynamics may offer insight into the possible evolutionary and ecological implications and general outcomes.

Coronaviruses in wild rodent and eulipotyphlan small mammals: a review of diversity, ecological implications and surveillance considerations.

Coronaviruses are abundant and diverse RNA viruses with broad vertebrate host ranges. These viruses include agents of human seasonal respiratory illness, such as human coronaviruses OC43 and HKU1; important pathogens of livestock and domestic animals such as swine acute diarrhoea syndrome coronavirus and feline coronavirus; and human pathogens of epidemic potential such as SARS-CoV, MERS-CoV and SARS-CoV-2. Most coronavirus surveillance has been conducted in bat species. However, small terrestrial mammals such as rodents and eulipotyphlans are important hosts of coronaviruses as well. Although fewer studies of rodent and eulipotyphlan coronaviruses exist compared to those of bats, notable diversity of coronaviruses has been reported in the former. No literature synthesis for this area of research has been completed despite (a) growing evidence for a small mammal origin of certain human coronaviruses and (b) global abundance of small mammal species. In this review, we present an overview of the current state of coronavirus research in wild terrestrial small mammals. We conducted a literature search for studies that investigated coronaviruses infecting rodent and eulipotyphlan hosts, which returned 63 studies published up to and including 2024. We describe trends in coronavirus diversity and surveillance for these studies. To further the examination of the interrelatedness of these viruses, we conducted a phylogenetic analysis of coronavirus whole genomes recovered from rodent and eulipotyphlan hosts. We discuss important facets of terrestrial small mammal coronaviruses, including evolutionary aspects and zoonotic spillover risk. Lastly, we present important recommendations and considerations for further surveillance and viral characterization efforts in this field.

Species-Specific Exudates From the Harmful Algae Alexandrium minutum and Prymnesium parvum Drive the Structure of a Synthetic Microbial Community.

In this study, we examined the role of species-specific algal exudates in shaping bacterial community structure and interactions using synthetic microbial communities co-cultured with Alexandrium minutum and Prymnesium parvum. Cell-free algal exudates supported bacterial growth as the sole carbon source and revealed distinct exometabolomes unique to each algal species. These exometabolomes selectively influenced bacterial community composition, even among common copiotrophic taxa. Furthermore, co-culture experiments highlighted that the presence of algal cells drove further bacterial assembly, particularly within particle-attached communities, emphasising the role of close algal-bacterial interactions in structuring microbial consortia. Metabolomic analyses showed significant modulation of algal exudates by bacteria, with axenic cultures containing a broader and more diverse range of metabolites. This suggests microbial consumption, degradation or suppression of metabolite production under xenic conditions. Importantly, we observed a bacterial-mediated increase in extracellular paralytic shellfish toxins (PSTs) in A. minutum cultures. Exudates of both algal species displayed hemolytic activity, which was not affected by the presence of bacteria, suggesting bioactive extracellular compounds (BECs) production does not rely on bacteria. These findings underscore the complex and dynamic nature of algal-bacterial interactions, with implications for nutrient cycling, toxin dynamics and harmful algal bloom ecology.

Salmonid sensory system development is affected by climate change driven temperature increases

Increases in water temperature due to global climate change are known to alter the course and timing of fish development. The mechanosensory lateral line (LL) system mediates flow-sensing behaviors vital for survival in fishes, but the effects of increased water temperatures resulting from climate change on its development have not been examined. Here LL development was documented in a cold-water salmonid (brook trout, Salvelinus fontinalis) reared at the thermograph of a long-term study stream (ambient) and two higher temperatures (+ 2 and + 4 °C) that reflect projected increases within their native range. At these two higher temperatures, fish reach crucial early life history transitions earlier (e.g., hatch, “swim-up” from gravel nests into the water column) and are larger in size through the parr (juvenile) stage. Early forming canal neuromast receptor organs are larger, and the process of canal morphogenesis is also accelerated suggesting potential consequences for neuromast function and presumably for LL-mediated behaviors. A potential mismatch between the timing of transitions in early life history stages, the ability to carry out LL-mediated behaviors (e.g., prey detection), and the timing of the seasonal emergence of their preferred prey, could have serious implications for cold-water salmonid ecology and survival.

Comprehensive research of some semi-volatile organic compounds (SVOCs) at very low levels in Lake and marine waters in Antarctica on-site by SBSE thermal desorption GC-MS/MS: Distribution, source apportionment, ecological and human health implication.

Comprehensive research of some semi-volatile organic compounds (SVOCs) at very low levels in Lake and marine waters in Antarctica on-site by SBSE thermal desorption GC-MS/MS: Distribution, source apportionment, ecological and human health implication.

Assessing strategies for remote island beach cleanups: Lessons from the Pacific and Alaska.

Assessing strategies for remote island beach cleanups: Lessons from the Pacific and Alaska.