Ecological Role Research Articles

Coastal Chronicles: Journey into the World of Coastal Systems

Coastal systems are complex and dynamic settings where the atmosphere, sea, and land combine to create a variety of landscapes, including coral reefs, beaches, and estuaries. These areas contribute to global sustainability initiatives delineated in the United Nations Sustainable Development Goals (SDGs), sustain biodiversity, and play crucial ecological and economic roles. For sustainable management and protection of coastal environments, it is imperative to possess an understanding of the physical attributes, biological constituents, and mechanisms that dictate their dynamics. The natural processes of tides, waves, and currents impact the geomorphology of coastal systems, resulting in the formation of features including dunes, beaches, estuaries, and deltas. Coastal vegetation that stabilizes sediments and supports a variety of habitats, like seagrasses, mangroves, and salt marshes, further enriches these landscapes. Fish, crabs, mollusks, and birds are among the coastal fauna that flourish in these habitats and add to the diversity of coastal life. However, human activities that accelerate natural processes like erosion, accretion, and sea-level riseuch as industrialization, pollution, and climate change pose an increasing threat to coastal systems. Thus, it is essential to use sustainable management techniques that strike a balance between development objectives and conservation initiatives. Coastal ecosystems must be protected and enhanced through the implementation of policies like Integrated Coastal Zone Management (ICZM), habitat restoration, and Marine Protected Areas (MPAs). A combination of mitigation and adaptation strategies, such as building coastal fortifications and promoting nature-based solutions, are also necessary for climate change adaption. We can ensure the resilience and vitality of coastal systems for present and future generations, as well as their sustained ecological and economic significance in the global environment, by tackling these intricate concerns cooperatively and comprehensively.

Evolution of the biochemistry underpinning purine alkaloid metabolism in plants.

Purine alkaloids are naturally occurring nitrogenous methylated derivatives of purine nucleotide degradation products, having essential roles in medicine, food and various other aspects of our daily lives. They are generated through convergent evolution in different plant species. The pivotal reaction steps within the purine alkaloid metabolic pathways have been largely elucidated, and the convergent evolution of purine alkaloids has been substantiated through bioinformatic, biochemical and other research perspectives within S-adenosyl-ʟ-methionine-dependent N-methyltransferases. Currently, the biological and ecological roles of purine alkaloids, further refinement of the purine alkaloid metabolic pathways and the investigation of purine alkaloid adaptive evolutionary mechanisms continue to attract widespread research interest. The exploration of the purine alkaloid metabolic pathways also enhances our comprehension of the biochemical mechanism, providing insights into inter-species interactions and adaptive evolution and offering potential value in drug development and agricultural applications. Here, we review the progress of research in the distribution, metabolic pathway elucidation and regulation, evolutionary mechanism and ecological roles of purine alkaloids in plants. The opportunities and challenges involved in elucidating the biochemical basis and evolutionary mechanisms of the purine alkaloid metabolic pathways, as well as other research aspects, are also discussed. This article is part of the theme issue 'The evolution of plant meta-bolism'.

Plant sesquiterpene lactones.

Sesquiterpene lactones (STLs) are a prominent group of plant secondary metabolites predominantly found in the Asteraceae family and have multiple ecological roles and medicinal applications. This review describes the evolutionary and ecological significance of STLs, highlighting their roles in plant defence mechanisms against herbivory and as phytotoxins, alongside their function as environmental signalling molecules. We also cover the substantial role of STLs in medicine and their mode of action in health and disease. We discuss the biosynthetic pathways and the various modifications that make STLs one of the most diverse groups of metabolites. Finally, we discuss methods for identifying and predicting STL biosynthesis pathways. This article is part of the theme issue 'The evolution of plant metabolism'.

Unveiling the Diversity and Ecological Roles of Macrofungi in Ayer Hitam Forest Reserve, Selangor, Malaysia

The biodiversity of macrofungi in remaining lowland dipterocarp forest in highly urbanization pressures is infrequently studied, even though their significant impact on the ecosystem of forested and non-forested habitats. Therefore, this research endeavours to unravel the diversity of macrofungi from different substrates in the Ayer Hitam Forest Reserve located in Selangor, Malaysia. Through a combination of field surveys, the study seeks to contribute valuable insights into the complex relationships between macrofungi and the surrounding habitats where macrofungal community structure was mainly influenced by substrate richness and microclimates. Sporocarps of macrofungi were collected from selected sites using opportunistic sampling methods. A total of 333 sporocarps were obtained and identified based on morphological and molecular analysis. Basidiomycota prevailed in the Ayer Hitam Forest Reserve where 27 species belonging to 14 families were successfully identified. Saprophytic fungi (22 species, 81.5%) dominated the areas, and a small number of mycorrhizal (1 species, 3.7%) and parasitic (4 species, 14.8%) fungi were found. Based on species diversity, order Polyporales is the highest occurrence species in the sampling areas with a Shannon-Weiner Index value of 2.103 and Simpson Index value of 0.954, Evenness Index value of 0.601, making it the most abundant order containing Microporus species, The findings are expected to enhance our knowledge of the biodiversity of macrofungi from different substrates in Ayer Hitam Forest Reserve, which can lead to conservation efforts and promote the ecological significance of macrofungi in tropical forest ecosystems.

Diversity and community distribution of soil bacterial in the Yellow River irrigation area of Ningxia, China.

The bacterial community performs an essential ecological role in maintaining agriculture systems. The roles of bacteria in the forest, marine, and agricultural systems have been studied extensively and intensively. However, similar studies in the areas irrigated by the Yellow River remain limited. In this study, we used Illumina sequencing analysis with the 16S rRNA method to analyze the bacterial diversity, community structure, and influencing factors in soil samples from eight regions of the Yellow River irrigation area in northwestern China. The bacterial community structure and diversity varied among samples from the eight regions. The samples differed significantly in terms of the bacterial community composition. Proteobacteria (approximately 12.4%-55.7%) accounted for the largest proportion and was the dominant bacteria, followed by Actinobacteria (approximately 9.2%-39.7%), Bacteroidetes (approximately 1.8%-21.5%), and Chloroflexi (approximately 2.7%-12.6%). Among the physicochemical variables, the soil pH in the eight regions was mildly alkaline, and the total nitrogen, total phosphorus, and total potassium contents in the soils differed significantly. However, the trend in the variations of the above variables was essentially similar. Soil bacteria in Yongning county had greater Chao1, Shannon-Wiener, and Simpson indices than those in the other regions. Notably, soil moisture, organic matter, and total nitrogen were recognized as the primary factors influencing the bacterial community in the Yellow River irrigation area. Our results revealed the laws of variation in soil bacterial diversity and community composition in the Yellow River irrigation area. Our findings could be beneficial for maintaining sustainable ecological practices in the Yellow River irrigation area.

Biomineralization and biomechanical trade-offs under heterogeneous environments in the eastern oyster Crassostrea virginica

ABSTRACT Accurate biological models are critical to reliably predict vulnerability of marine organisms and ecosystems to rapid environmental changes. Current predictions on the biological impacts of climate change and human-caused disturbances primarily stem from controlled experiments but lack assessments of the mechanisms underlying biotic variations in natural systems, especially for habitat-forming, climate-sensitive species with key ecological roles. This study aimed to characterize and quantify spatial patterns of shell biomineralization and biomechanical properties in a key reef-building oyster, Crassostrea virginica, collected from restored reefs along natural estuarine gradients in the Hudson River Estuary (NY, USA). We characterized patterns of oyster shell deposition, structure, composition and mechanical performance at the macro- and microscale. Eastern oysters show a strong capacity for adjustments in shell biomineralization and biomechanics to maintain shell production and protective functions. We reveal salinity as a key predictor of oyster shell structure, mechanical integrity and resistance to dissolution, and describe the functional role of chalky calcite in shaping shell mechanical performance. Changes in shell production along salinity gradients indicate formation of shells with (1) high mechanical resistance but increased vulnerability to dissolution under marine conditions and (2) lower structural integrity but higher protection from dissolution under brackish conditions. Our work illustrates that biomineralization and biomechanical trade-offs may act as mechanisms in eastern oysters to maintain overall performance under heterogeneous estuarine environments and could represent a cornerstone for calcifying organisms to acclimate and maintain their ecological functions in a rapidly changing climate.

Unique Features of Extremely Halophilic Microbiota Inhabiting Solar Saltworks Fields of Vietnam.

The artificial solar saltworks fields of Hon Khoi are important industrial and biodiversity resources in southern Vietnam. Most hypersaline environments in this area are characterized by saturated salinity, nearly neutral pH, intense ultraviolet radiation, elevated temperatures and fast desiccation processes. However, the extremely halophilic prokaryotic communities associated with these stressful environments remain uninvestigated. To fill this gap, a metabarcoding approach was conducted to characterize these communities by comparing them with solar salterns in northern Vietnam as well as with the Italian salterns of Motya and Trapani. Sequencing analyses revealed that the multiple reuses of crystallization ponds apparently create significant perturbations and structural instability in prokaryotic consortia. However, some interesting features were noticed when we examined the diversity of ultra-small prokaryotes belonging to Patescibacteria and DPANN Archaea. Surprisingly, we found at least five deeply branched clades, two from Patescibacteria and three from DPANN Archaea, which seem to be quite specific to the Hon Khoi saltworks field ecosystem and can be considered as a part of biogeographical connotation. Further studies are needed to characterize these uncultivated taxa, to isolate and cultivate them, which will allow us to elucidate their ecological role in these hypersaline habitats and to explore their biotechnological and biomedical potential.

Attraction of Sweet Potato Whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae), and Two Generalist Predators to Green Leaf Volatile Compounds.

Traditionally, olfaction was thought to play a minor role in the behavioral ecology of the sweet potato whitefly, Bemisia tabaci (Gennadius). However, recent research is uncovering significant potential for whitefly management based on olfaction. Incorporating chemical attractants with standard whitefly management programs could significantly improve control. The integration of attractants with biological control is exceptionally promising. Therefore, the behavioral response of B. tabaci and two generalist predators to the green leaf volatiles (E)-2-hexenal, (Z)-3-hexenal, (Z)-3-hexenyl acetate, and (Z)-3-hexe-1-ol were investigated in Y-tube olfactometers. Three of the four green leaf volatiles resulted in the attraction of female B. tabaci. Blend optimization indicated a two-chemical blend to be the most attractive blend for female B. tabaci. In addition, this blend was attractive to female Macrolophus praeclarus (Distant) but did not elicit a behavioral response from either male or female Delphastus catalinae (Horn). The two-chemical blend of green leaf volatiles could be further developed as a lure to attract B. tabaci and its predator, M. praeclarus.

Trophic niche of a nonnative invader and environmental drivers of its increasing populations in the coastal Everglades

AbstractThe Florida Everglades is a critically important, but highly threatened ecosystem that is becoming increasingly susceptible to the invasion of non-native species. This study investigated the ecological role of the invasive peacock eel (Macrognathus siamensis) within this ecosystem using 15 years of electrofishing data and stable isotope analysis. We investigated the population trends of peacock eels at the marsh-mangrove ecotone of the Shark River Estuary, the environmental factors contributing to their abundance, and the potential interactions they may have with native fish assemblages and coastal food webs. We used stable isotope analysis to provide insights into the basal resource contribution to peacock eels and hypervolume analysis to determine peacock eel trophic niche size and overlap with native species. Results of this study found that peacock eel abundance has rapidly increased, and their populations are strongly related to hydroclimatic regimes. Peacock eel abundance was positively associated with warmer water temperatures and greater marsh inundation periods. The trophic niche of peacock eels was significantly smaller in volume than that of native sunfishes (Lepomis spp.) indicating lower intraspecific resource use variability and suggesting a limited potential for inter-specific competition with these taxa. However, in recent years, the catch of peacock eels has outnumbered the catch of all native sunfishes combined. The feeding habits and pervasiveness of peacock eels in the coastal Everglades could lead to a decrease in abundance of benthic prey items targeted by peacock eels and alter food web dynamics in the system. Based on these data, peacock eel populations are predicted to continue to increase, highlighting the importance of continued monitoring of their potential impact on native fish assemblages and food webs.

Farmers’ Perception of Shelter Forests and the Influencing Factors in Windy Desert Areas of the Hexi Corridor, China

Shelter forest systems in the sandy areas mainly comprise farmland shelter forests (FSF) and windbreak and sand-fixing forests (WSF). Through a questionnaire survey of farmers in the oasis–desert transition zone of the windy desert areas of the Hexi Corridor in China, a perception assessment model of farmers’ perception of the status quo and ecosystem service function of shelter forests was constructed, and the willingness of farmers to pay for shelter forest construction and protection was measured. Influencing factors for the farmers’ perception of shelter forests were analyzed by a multiple regression analysis. The results showed problems with pests and diseases all present in FSF and WSF, the destruction of farmland in FSF, and water scarcity in WSF. Farmers evaluated the ecological role of shelter forests as the most obvious in windbreak and sand fixation; intermediate in the four ecological roles of leisure and recreation, agricultural production, a sense of locality, and climate regulation; and the smallest in soil improvement. Nearly 95% of farmers are willing to donate funds to shelter forest construction and protection, and the average amount the farmers were willing to pay was CNY 54.30 per year. Willingness to pay, annual household income, gender, environmental experience, age, and interview area have significant effects on farmers’ perception of shelter forests. Finally, in this paper, we recommend increasing motivation through government financial support and training for farmers to address pests and diseases, water security, and the destruction of farmland in shelter forests to ensure healthy and sustainable growth.

Distinct Communities of Bacteria and Unicellular Eukaryotes in the Different Water Masses of Cretan Passage Water Column (Eastern Mediterranean Sea).

Elucidating marine microbiota diversity and dynamics holds significant importance due to their role in maintaining vital ecosystem functions and services including climate regulation. This work aims to contribute in the understanding of microbial ecology and networking in one of the world's most understudied marine regions, the Eastern Mediterranean Sea. High-throughput 16S and 18S rRNA gene sequencing analysis was applied to study the diversity of bacteria and unicellular eukaryotes in the different water masses of the Cretan Passage during two seasonally-different sampling expeditions. We assumed that microbial associations differ between the surface and deepwater masses and created co-occurrence networks to evaluate this hypothesis. Our results unveiled vertical variations in both bacterial and unicellular eukaryotic diversity with species fluctuations indicative of seasonality being recorded in the surface water mass. Heterotrophic taxa and grazers related to organic matter degradation and nutrient cycling were enriched in the deepest water layers. Moreover, surface waters presented a higher number of microbial associations indicating abundant ecological niches compared to the deepest layer, possibly related to the lack of bottom-up resources in the oligotrophic deep ocean. Overall, our data provide insight in a heavily stressed, yet underexplored, marine area that requires further research to unravel the ecological roles of marine microbes. To our knowledge, this is the first study that combines molecular biology tools to provide data on both planktic prokaryotes and unicellular eukaryotes across the different water masses in this marine region of the Eastern Mediterranean basin.

Bacterial amino acid chemotaxis: a widespread strategy with multiple physiological and ecological roles.

Chemotaxis is the directed, flagellum-based movement of bacteria in chemoeffector gradients. Bacteria respond chemotactically to a wide range of chemoeffectors, including amino, organic, and fatty acids, sugars, polyamines, quaternary amines, purines, pyrimidines, aromatic hydrocarbons, oxygen, inorganic ions, or polysaccharides. Most frequent are chemotactic responses to amino acids (AAs), which were observed in numerous bacteria regardless of their phylogeny and lifestyle. Mostly chemoattraction responses are observed, although a number of bacteria are repelled from certain AAs. Chemoattraction is associated with the important metabolic value of AAs as growth substrates or building blocks of proteins. However, additional studies revealed that AAs are also sensed as environmental cues. Many chemoreceptors are specific for AAs, and signaling is typically initiated by direct ligand binding to their four-helix bundle or dCache ligand-binding domains. Frequently, bacteria possess multiple AA-responsive chemoreceptors that at times possess complementary AA ligand spectra. The identification of sequence motifs in the binding sites at dCache_1 domains has permitted to define an AA-specific family of dCache_1AA chemoreceptors. In addition, AAs are among the ligands recognized by broad ligand range chemoreceptors, and evidence was obtained for chemoreceptor activation by the binding of AA-loaded solute-binding proteins. The biological significance of AA chemotaxis is very ample including in biofilm formation, root and seed colonization by beneficial bacteria, plant entry of phytopathogens, colonization of the intestine, or different virulence-related features in human/animal pathogens. This review provides insights that may be helpful for the study of AA chemotaxis in other uncharacterized bacteria.

Seagrass Meadows: Prospective Candidates for Bioactive Molecules.

Seagrass meadows consist of angiosperms that thrive fully submerged in marine environments and form distinct ecosystems. They provide essential support for many organisms, acting as nursery grounds for species of economic importance. Beyond their ecological roles, seagrasses and their associated microbiomes are rich sources of bioactive compounds with the potential to address numerous human healthcare challenges. Seagrasses produce bioactive molecules responding to physical, chemical, and biological environmental changes. These activities can treat microbe-borne diseases, skin diseases, diabetes, muscle pain, helminthic diseases, and wounds. Seagrasses also offer potential secondary metabolites that can be used for societal benefits. Despite numerous results on their presence and bioactive derivatives, only a few studies have explored the functional and therapeutic properties of secondary metabolites from seagrass. With the increasing spread of epidemics and pandemics worldwide, the demand for alternative drug sources and drug discovery has become an indispensable area of research. Seagrasses present a reliable natural source, making this an opportune moment for further exploration of their pharmacological activities with minimal side effects. This review provides a comprehensive overview of the biochemical, phytochemical, and biomedical applications of seagrasses globally over the last two decades, highlighting the prospective areas of future research for identifying biomedical applications.

Peptide-Driven Assembly of Magnetic Beads for Potentiometric Sensing of Bacterial Enzyme at a Subcellular Level.

Bacterial enzymes with different subcellular localizations play a critical ecological role in biogeochemical processing. However, precisely quantifying enzymes localized at certain subcellular levels, such as extracellular enzymes, has not yet been fully realized due to the complexity and dynamism of the bacterial outer membrane. Here we present a magneto-controlled potentiometric sensing platform for the specific detection of extracellular enzymatic activity. Alkaline phosphatase (ALP), which is one of the crucial hydrolytic enzymes in the ocean, was selected as the target enzyme. Magnetic beads functionalized with an ALP-responsive self-assembled peptide (GGGGGFFFpYpYEEE, MBs-peptides) prevent negatively charged peptides from entering the bacterial outer membrane, thereby enabling direct potentiometric sensing of extracellular ALP both attached to the bacterial cell surface and released into the surrounding environment. The dephosphorylation-triggered assembly of peptide-coupled magnetic beads can be directly and sensitively measured by using a magneto-controlled sensor. In this study, extracellular ALP activity of Pseudomonas aeruginosa at concentrations ranging from 10 to 1.0 × 105 CFU mL-1 was specifically and sensitively monitored. Moreover, this magneto-controlled potentiometric method enabled a simple and accurate assay of ALP activity across different subcellular localizations.

Acanthocephalan Profilicollis altmani infecting the mole crab Emerita brasiliensis in southeastern Brazil

Acanthocephalan parasites, specifically from the genus Profilicollis, are known to infect decapod crustaceans, including mole crabs like Emerita brasiliensis, which serve as intermediate hosts in their complex life cycles. This study reports the first occurrence of the acanthocephalan parasite Profilicollis altmani infecting the mole crab Emerita brasiliensis on a sandy beach in southeastern Brazil, thereby expanding the known geographic range of this parasite. Additionally, the study provides novel molecular data that enhance our understanding of the parasite’s taxonomy and distribution, including the first evidence of genetic variation within populations of the intermediate host E. brasiliensis. Phylogenetic analysis based on mitochondrial COX1 gene sequences confirmed the identification of the parasite and underlined small genetic differences among P. altmani populations. These findings suggest a weak genetic population structure of the parasite and underscore the need for further studies to understand gene flow among these populations. This work contributes to the knowledge of parasite-host interactions in sandy beach ecosystems. It highlights the importance of monitoring parasitic infections in species like E. brasiliensis, which play a crucial ecological role in these environments.

The role of mouse tails in response to external and self-generated balance perturbations on the roll plane.

Chordate tails exhibit considerable morphological and functional diversity, with variations in length, diameter and texture adapted to various ecological roles. While some animals, including humans, have lost or reduced their tails, many vertebrates retain and use their tails for activities such as balancing, climbing and escaping predators. This study investigates how laboratory mice (Mus musculus) use their tails to maintain balance when dealing with external and self-generated perturbations. Mice crossed platforms of different widths, while responding to roll-plane tilts. Our findings show that mice swing their tails to counteract external roll perturbations, generating angular momentum to stabilize themselves. Mice were also found to use active (dynamic stabilizer) and passive (counterweight) tail movement strategies when locomoting on narrow platforms. The results suggest that the tail is a core component of mouse locomotion, especially in challenging balancing conditions.

Endophytic Bacterial Biofilm-Formers Associated with Antarctic Vascular Plants.

Deschampsia antarctica and Colobantus quitensis are the only two vascular plants colonized on the Antarctic continent, which is usually exposed to extreme environments. Endophytic bacteria residing within plant tissues can exhibit diverse adaptations that contribute to their ecological success and potential benefits for their plant hosts. This study aimed to characterize 12 endophytic bacterial strains isolated from these plants, focusing on their ecological adaptations and functional roles like plant growth promotion, antifungal activities, tolerance to salt and low-carbon environments, wide temperature range, and biofilm formation. Using 16S rRNA sequencing, we identified several strains, including novel species like Hafnia and Agreia. Many strains exhibited nitrogen-fixing ability, phosphate solubilization, ammonia, and IAA production, potentially benefiting their hosts. Additionally, halotolerance and carbon oligotrophy were also shown by studied bacteria. While some Antarctic bacteria remain strictly psychrophilic, others demonstrate a remarkable ability to tolerate a wider range of temperatures, suggesting that they have acquired mechanisms to cope with fluctuations in environmental temperature and developed adaptations to survive in intermediate hosts like mammals and/or birds. Such adaptations and high plasticity of metabolism of Antarctic endophytic bacteria provide a foundation for research and development of new promising products or mechanisms for use in agriculture and technology.

Management of jellyfish outbreaks to achieve good environmental status

Jellyfish and gelatinous zooplankton (GZ) in general, fulfill important ecological roles with significant impacts, although they are often oversimplified or misunderstood. This paper reviews the impacts, pressures, monitoring methods and current management strategies for various GZ groups. It also introduces potentially applicable indicators for their assessment in ecosystem-based management approaches, such as the European Marine Strategy Framework Directive (MSFD). This multi-faceted review is primarily envisioned to serve as a state-of-the-art document for scientists and policymakers to foster a holistic assessment and management of GZ across European regional seas. The systematic review on global impacts of GZ shows a notable increase in the number of studies since the early 2000s. Stings were the main cause of human health impacts. Mechanisms that impact biodiversity included direct predation, modification of trophic flows or competition for resources. Several GZ taxa may be beneficial to biodiversity acting as biological regulators and provide societal ecosystem services such as food provision or medical applications. The systematic review on monitoring techniques outlined a variety of methods, such as nets (the most common technique), continuous plankton recorder (CPR), polyp and jelly-fall monitoring, acoustic methods, remote aerial and underwater imaging, molecular methods, and citizen science. Furthermore, several currently employed management strategies were enumerated, including the use of anti-jelly nets, bubble curtains, chemical compounds, or the introduction of GZ predators. This study highlights the pressing need for enhanced GZ-dedicated monitoring, assessment, and anticipatory management of GZ populations to address future GZ crises more effectively and cost-efficiently. Moreover, exploring GZ ecosystem services unveils opportunities to harness marine resources while mitigating adverse effects, thereby supporting sustainable blue economies.

Measuring standardized functional leaf traits of aquatic carnivorous plants – challenges and opportunities

Aquatic carnivorous plants (ACP) are an important component of humic nutrient-poor freshwater environments. However, these habitats are facing multiple impacts that ultimately lead to habitat degradation and declining ACP populations. Functional traits, particularly those within the leaf economics spectrum, are a valuable tool for studying plant adaptation strategies and plasticity. Given their unique morphological structure, ACP are essentially excluded from functional comparisons, which potentially limits our knowledge about the ecological roles of these species compared to non-carnivorous ones. In this study, we developed a protocol for measuring the leaf functional traits of ACP (leaf fresh and dry weight, leaf area, leaf dry matter content, specific leaf area, leaf pigment content, leaf phosphorus, nitrogen and carbon contents), and carnivory-related traits (number of traps and investment in carnivory). We measured 15 traits in seven ACP species (Aldrovanda vesiculosa, Utricularia australis, U. bremii, U. intermedia, U. ochroleuca, U. stygia, U. vulgaris), grown in the outdoor collection of aquatic and wetland plants of the Institute of Botany CAS at Třeboň, the Czech Republic. We used the functional traits of other macrophyte groups/species (lemnids, Nuphar lutea, Ceratophyllum demersum), collected with a similar methodology, to assess the comparability of ACP traits. We identified the “functional unit”, a modular structure, including one leaf node, plus an internode, which performs the function of a leaf in ACP, and selected its position along the stem to reflect species-specific growth rates. We collected 714 new trait records for the target ACP. Based on a multivariate trait space representation (PCA), ACP were distinct from the other macrophyte groups/species, which highlights these species’ structural and physiological peculiarities. Nonetheless, ACP entirely overlapped the comparison data along the first PCA axis, and most of the traits lay within the ranges observed for other macrophyte groups/species, which demonstrates the comparability of the ACP traits measured by the new protocol. Applying this protocol in ecological studies could shed light on the adaptations of ACP to environmental variability, with important conservation implications.

Once Upon a Time, “About 1.170 Results”: Exploring the Narrative Power of Search Engines

Search engines play a pivotal role in online ecology and can have a significant impact on people, especially in the case of a name search. The pros and cons of removing search results have been at the heart of an ongoing debate revolving around “the right ro be forgotten” (art. 17 of the General Data Protection Regulation). This article proposes to contribute the discussion by philosophically reflecting on the transformative power of search engines in relation to original content. It shows that the implications of search engines run deeper than the mere display of faulty or outdated content. In order to reveal and conceptualise the impact that search engines have on the information they present, this article operationalises Ricoeur’s notion of ‘semantic autonomy’ in a digital context. This offers a framework that is used to analyse the transformative power of search engines across several dimensions: the relation to authors, audiences, the message and the semantic value of content. The article concludes that search engines have a transformative power that may bypass human intentions on multiple levels and, to a certain degree, allows them to ‘tell a story’ on their own.