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Progress in genome screening technologies is improving our understanding of how hybridization contributes to the tree of life. Beyond the formation of new gene combinations and species, hybridization can promote biological novelty by triggering or reshaping the whole range of ecological interactions. With the increasing realization that hybridization is widespread in nature, and that human-driven environmental changes will boost its frequency of occurrence, the time is ripe for pinning down the ecological roles of hybridization. Hybridization as an evolutionary process has been studied in depth over the past few decades. Research has focused on its role in shaping reproductive barriers, its adaptive value, and its genomic consequences. In contrast, our knowledge of ecological dimensions of hybridization is still in its infancy, despite hybridization being an inherently ecological interaction. Using examples from various organisms, we show that hybridization can affect and be affected by non-reproductive interactions, including predation, competition, parasitism, mutualism, commensalism, and organism–environment interactions, with significant implications for community structure and ecosystem functioning. However, since these dimensions of hybridization have mostly been revealed from studies designed to decipher other evolutionary processes, we argue that much of the eco-evolutionary importance of hybridization is yet to be discovered. [ABSTRACT FROM AUTHOR]

• High-resolution imaging can reveal relationships between phytoplankton genera. • Pseudo-nitzschia tends to bloom concurrently with or right after other phytoplankton. • Such bloom periods coincide with higher water temperatures and lower salinity. • The width of Pseudo-nitzschia chains or their estimated biovolume may be used to approximate harmful algal bloom risk in the absence of toxin data. Phytoplankton populations in the natural environment interact with each other. Despite rising global concern with Pseudo-nitzschia blooms, which can produce the potent neurotoxin domoic acid, we still do not fully understand how other phytoplankton genera respond to the presence of Pseudo-nitzschia. Here, we used a 4-year high-resolution imaging dataset for 9 commonly found phytoplankton genera in Narragansett Bay, alongside environmental data, to identify potential interactions between phytoplankton genera and their response to elevated Pseudo-nitzschia abundance. Our results indicate that Pseudo-nitzschia tends to bloom either concurrently with or right after other phytoplankton genera. Such bloom periods coincide with higher water temperatures and lower salinity. Pseudo-nitzschia image abundance tends to increase the most from March-May and peaks during May-Jun, whereas the image-derived biovolume and width of Pseudo-nitzschia chains increase the most during Jan-Feb. For most phytoplankton genera, their relationship with Pseudo-nitzschia abundance is noticeably different from their relationship with Pseudo-nitzschia image features. Despite the complexity in the phytoplankton community, our analysis suggests several ecological indicators that may be used to determine the risk of harmful algal blooms. [ABSTRACT FROM AUTHOR]

Recent advances in microbial electrochemical technologies have revealed the existence of numerous and highly diverse microorganisms able to exchange electrons with electrodes. This diversity could reflect the capacity of microorganisms to release and/or retrieve electrons with each other in natural environments. So far, this interspecies electron transfer has been studied with a special focus on syntrophy and was successfully demonstrated for several couples of species. In this article we argue that electron exchange between microbes exists beyond syntrophy or mutualism and could also promote competitive and even parasitic behaviour. Based on three interesting case studies identified from the literature, we also highlight that such nonmutualistic interactions could be widespread and of particular significance for the survival of pathogens or the shaping of complex microbial communities. The development of bioelectrochemistry has revealed a wide diversity of electroactive microorganisms able to exchange electrons with electrodes through mechanisms of extracellular electron transfer. In nature, these mechanisms can be used by electron-donating microbes to reach distant or nonsoluble terminal electron acceptors such as iron oxides or other microorganisms. So far, research on microbe-to-microbe electron transfer has exclusively been focused on mutualistic interactions. It has been experimentally demonstrated that some fermentative species can accept extracellular electrons, even when it is detrimental to their growth yield, which supports the existence of nonmutualistic interspecies electron transfer. [ABSTRACT FROM AUTHOR]

In sub/tropical waters, benthic foraminifera are among the most abundant epiphytic organisms inhabiting seagrass meadows. This study explored the nature of the association between foraminifera and the tropical seagrass species H. stipulacea , aiming to determine whether these interactions are facilitative or random. For this, we performed a "choice" experiment, where foraminifera could colonize H. stipulacea plants or plastic "seagrasses" plants. At the end of the experiment, a microbiome analysis was performed to identify possible variances in the microbial community and diversity of the substrates. Results show that foraminifera prefer to colonize H. stipulacea , which had a higher abundance and diversity of foraminifera than plastic seagrass plants, which increased over time and with shoot age. Moreover, H. stipulacea leaves have higher epiphytic microbial community abundance and diversity. These results demonstrate that seagrass meadows are important hosts of the foraminifera community and suggest the potential facilitative effect of H. stipulacea on epiphytic foraminifera, which might be attributed to a greater diversity of the microbial community inhabiting H. stipulacea. [Display omitted] • A "choice" experiment was performed to study settlement preferences of benthic foraminifera. • Benthic foraminifera significantly chose to colonize H. stipulacea. • Epiphytic foraminifera had a preference for root and rhizome compartments. • High epiphytic microbial community on old leaves might encourage foraminifera settlement. • Seagrass meadows are essential hosts of foraminifera. [ABSTRACT FROM AUTHOR]

Our knowledge of host-associated microorganisms and their role in host functions is rapidly evolving. Stress-affected plants assemble beneficial microbes in their rhizosphere to maximize survival and growth. Similarly, insects have gut microbiomes that extend their functional repertoire in fighting stress. A strong microbial linkage between soil, plants, and pollinators is emerging and this can influence pollination services and overall ecosystem health. Yet, the nature of microbial interactions between different ecosystem components remains poorly understood. Here we highlight the acquisition pathways of beneficial microbes and their functions in protecting hosts against stress. By adopting a new 'eco-holobiont' approach, which explicitly incorporates biotic feedbacks, we can significantly expand our ecological understanding and better develop sustainable environmental management. Host holobionts extend host capacity for nutrient uptake and stress protection. Stress-affected plants promote the accumulation of beneficial microbes in the rhizosphere, putatively driven by an alteration of root exudates. Such a 'cry for help' strategy increases plant survival rates under stress. Gut microbiomes of insect pollinators play multifunctional roles in host growth, development, and immunity. They can be switched to dysbiotic conditions when exposed to agrochemicals, with negative consequences for host health and survival. Recent evidence shows that flowers have a microbiome that both interacts with foraging pollinators and can be inherited by seeds. It provides a microbial link between soil, plants, and pollinators. Adopting a new 'eco-holobiont' approach can expand our ecological understanding and help to develop sustainable environmental management. [ABSTRACT FROM AUTHOR]

Abstract Efficient biodiversity management strategies aim to allocate conservation efforts so as to maximize diversity in ecological systems. Toward this end, defining a diversity criterion is an important but challenging task, as several different indices can be used as biodiversity measures. This paper elicits and compares two criteria for biodiversity conservation based on indices stemming from different disciplines: Weitzman's index in economics and Rao's index in ecology. These indices use different approaches to combine information about measures of (1) the probability distributions of the species that are present in an ecosystem (i.e. survival probabilities) and (2) the degree of dissimilarity between these species. As an important step toward in situ conservation criteria, we add to these elements information about (3) the ecological interactions that take place between species. Considering a simple three-species ecosystem, we show that criterion choice has palpable policy implications, as it can sometimes lead to divergent management recommendations. We disentangle the roles played by elements (1), (2) and (3) in the ranking of outcomes, which allows us to highlight several specificities of the two criteria. An important result is that, other things being equal, Weitzman's in situ ranking tends to favor robust species that are least concerned with extinction, while Rao's in situ ranking generally gives priority to more vulnerable species that are closer to extinction. [ABSTRACT FROM AUTHOR]

Abstract The rise in global demand for seafood has led many people to view shellfish aquaculture as an economically and ecologically viable source of seafood. However, interactions with the environment, existing industry, and societal values must be considered to ensure sustainability of this industry. Shellfish aquaculture in British Columbia (BC), Canada, showcases many of these issues. This review explores key socio-economic and ecological considerations for future growth of shellfish aquaculture on the central and north coast of BC, with implications for the continuing global expansion of the industry. Interactions among shellfish aquaculture, coastal groups, existing industries, and First Nations, as well as considerations under changing oceanic conditions are investigated. Expansion of shellfish aquaculture on the central and north coast of BC will need to be socially, environmentally, and economically sustainable. The results of this review strongly indicate that shellfish aquaculture should be incorporated in marine planning initiatives and developed in consideration of local ecological, environmental, economic, and social context. [ABSTRACT FROM AUTHOR]

Highlights • Pollination is an important ecosystem service. • Plant-pollinator networks can be sensitive to the loss of certain pollinators. • We quantified the topology of pollination networks by distance-based fragmentation. • We performed this analysis for 16 habitat types embedded in the same landscape. • Sensitivity to the loss of honeybee, a key pollinator, depends on community structure. Abstract The populations of most pollinators, including honeybees, are declining that heavily affects both crop and wild plant pollination. Wild bee diversity and habitat type may modulate these effects. We addressed the question how the structure of plant-pollinator networks in different habitat types may influence the vulnerability of pollinator communities to the hypothetical loss of honeybees. We performed network analysis based on plant-visitation data in a traditional agricultural landscape and quantified the structural vulnerability (i.e. the effect of the loss of honeybee) of the plant-pollinator networks by a topological index (distance-based fragmentation). We found that very different plant-pollinator communities inhabited the studied different agricultural habitat types. The early summer arable fields had the most, pastures in mid-summer had the less vulnerable structure and, in general, an intermediate plant/pollinator ratio was associated with high vulnerability in the absence of honeybees. We suggest that increased plant species richness can ensure higher wild bee diversity and more stable plant-pollinator networks without honeybee, where flower-visitation can rely more on wild bees. Decreased management intensity in agricultural landscapes can therefore contribute to the maintenance of diverse plant-pollinator communities in agricultural landscapes and to sustainable farming. [ABSTRACT FROM AUTHOR]

The effect of ocean warming and acidification on predator-prey interactions in the intertidal zone is a topic of growing concern for the scientific community. In this review, we aim to describe how scientists have explored the topic via research weaving, a combination of a systematic review, and a bibliometric approach. We assess articles published in the last decade exploring the impact of both stressors on predation in the intertidal zone, via experimental or observational techniques. Several methods were used to delve into how climate change-induced stress affected intertidal predation, as the study design leaned toward single-based driver trials to the detriment of a multi-driver approach. Mollusks, echinoderms, and crustaceans have been extensively used as model organisms, with little published data on other invertebrates, vertebrates, and algae taxa. Moreover, there is a strong web of co-authoring across institutions and countries from the Northern Hemisphere, that can skew our understanding towards temperate environments. Therefore, institutions and countries should increase participation in the southern hemisphere networking, assessing the problems under a global outlook. Our review also addresses the various impacts of ocean acidification, warming, or their interaction with predation-related variables, affecting organisms from the genetic to a broader ecological scope, such as animal behaviour or interspecific interactions. Finally, we argue that the numerous synonyms used in keywording articles in the field, possibly hurting future reviews in the area, as we provide different keyword standardizations. Our findings can help guide upcoming approaches to the topic by assessing what has been already done and revealing gaps in emerging themes, like a strong skew towards single-driver (specially acidification) lab experiments of northern hemisphere organisms and a lack of field multi-stressor experiments. • Review about climate change impacts on intertidal predator-prey interaction. • Research weaving focusing on the scientific literature from the 2010's • Prevalence of single-stressor acidification studies about invertebrates • Countries need to expand their collaborations towards the southern hemisphere • Lack of standardization of keywords may be hindering future reviews about the field [ABSTRACT FROM AUTHOR]

Abstract Sponges are sessile benthic filter-feeding animals, which harbor numerous microorganisms. The enormous diversity and abundance of sponge associated bacteria envisages sponges as hot spots of microbial diversity and dynamics. Many theories were proposed on the ecological implications and mechanism of sponge-microbial association, among these, the biosynthesis of sponge derived bioactive molecules by the symbiotic bacteria is now well-indicated. This phenomenon however, is not exhibited by all marine sponges. Based on the available reports, it has been well established that the sponge associated microbial assemblages keep on changing continuously in response to environmental pressure and/or acquisition of microbes from surrounding seawater or associated macroorganisms. In this review, we have discussed nutritional association of sponges with its symbionts, interaction of sponges with other eukaryotic organisms, dynamics of sponge microbiome and sponge-specific microbial symbionts, sponge-coral association etc. Highlights • Intends to describe sponge associated unique microbial symbionts. • An insight of eukaryotic symbionts-fungi, yeast etc., • Visualization of coral killing sponge T. hoshinota , Terpios. • Influence of environmental factors on sponge association. [ABSTRACT FROM AUTHOR]

Anthropogenic climate change is one of the main current threats to biodiversity, and it has been linked to species decline. Bats deserve attention because they occupy different trophic niches and perform different functions in nature, acting as flower pollinators (nectarivores), seed dispersers (frugivores), and pest controllers (insectivores). The effects of climate change on the distribution of bat species occurring in the Carajás National Forest (Eastern Amazon, southeastern Pará state, Brazil) was examined by modeling species distributions. A total of 83 species of bats providing the above mentioned services were analyzed for the years 2050 and 2070 to answer the following two questions: (i) Which species are potentially more sensitive to climate changes and will not be able to find suitable areas in Carajás in the future, and (ii) Which are the priority areas that protect the greatest number of species from climate change. Of the total species analyzed, 47 (57%) will potentially not find suitable areas in Carajás under the scenarios employed. Pollinators, seed dispersers, and more-generalist (omnivorous) bats will potentially be the most affected, suffering a 28–36% decrease in suitable area under the 2070 scenario, which may have implications for the plants with which those species interact. According to the scenarios employed, the Carajás National Forest, as well as other conservation units in Pará, will not protect most species in the future. The most suitable areas are located mainly to the north and west of the state and under varying degrees of conservation: from well-preserved protected areas to areas degraded due to different anthropogenic impacts. This study emphasizes that the possible effect of climate change and the location of species protection areas need to be analyzed together to ensure that the areas that will act as potential climate refuges for species in the future are indeed protected. [ABSTRACT FROM AUTHOR]

Semantic heterogeneity hampers efforts to find, integrate, analyse and interpret ecological data. An application case-study is described, in which the objective was to automate the integration and interpretation of heterogeneous, flower-visiting ecological data. A prototype knowledge-based system is described and evaluated. The system's semantic architecture uses a combination of ontologies and a Bayesian network to represent and reason with qualitative, uncertain ecological data and knowledge. This allows the high-level context and causal knowledge of behavioural interactions between individual plants and insects, and consequent ecological interactions between plant and insect populations, to be discovered. The system automatically assembles ecological interactions into a semantically consistent interaction network (a new design of a useful, traditional domain model). We discuss the contribution of probabilistic reasoning to knowledge discovery, the limitations of knowledge discovery in the application case-study, the impact of the work and the potential to apply the system design to the study of ecological interaction networks in general. [ABSTRACT FROM AUTHOR]

• Tree diversity and traits are important for epiphytic bryophytes-phorophytes network. • Ecological interactions of epiphytic bryophytes and phorophytes were explored. • Biodiversity conservation of epiphytic bryophytes and phorophytes are consistent. The Qinghai-Tibet Plateau (QTP), the highest and largest plateau in the world, plays a vital role in maintaining the balance of the global ecosystem and China's ecological barriers. The QTP ecosystems are facing serious challenges under the scenario of global climate change. Epiphytic plant diversity is one of the most significant contributors to forest diversity. Epiphytic bryophytes play an important role in forest ecosystem functioning. However, previous studies of epiphytic bryophyte diversity have rarely considered both phorophyte diversity and their ecological networks, factors that are crucial for revealing the ecological processes of community assembly and the mechanisms of biodiversity maintenance and ecosystem stability. We investigated the diversity of epiphytic bryophytes and their host trees in 18 forest sites in the southeastern QTP and analyzed the characteristics of their ecological network. A total of 57 epiphytic bryophyte species in 35 genera and 24 families and 72 individuals of host trees belonging to 14 genera and 10 families were recorded. Epiphytic bryophyte species on Picea , Abies , and Sorbus accounted for 77% of all species. The ecological network structure of epiphytic bryophytes-phorophytes exhibited low connectance and nestedness and a low degree of specialization. The cover of epiphytic bryophytes was significant positively correlated with host tree size (diameter at breast height) and not significantly correlated with bark roughness. Both tree size and bark roughness were weakly positively correlated with epiphytic bryophyte richness. The study results showed that increasing tree diversity is essential for the maintenance of the epiphytic bryophyte diversity in forests of the QTP. Biodiversity conservation of epiphytic bryophytes is consistent with conservation of their host trees. [ABSTRACT FROM AUTHOR]

Our model considers a new element in forest fire modeling, namely the dynamics of a forest animal, intimately linked to the trees. We show that animals and trees react differently to different types of fire. A high probability of fire initiation results in several small fires, which do not allow for a large fuel accumulation and thus the destruction of many trees by fire, but is found to be generally devastating to the animal population at the same time. On the other hand, a low fire initiation probability allows for the accumulation of higher quantities of fuel, which in turn results in larger fires, more devastating to the trees than to the animals. Thus, we suggest that optimal fire management should take into account the relation between fire initiation and its different effects on animals and trees. Further, wildfires are often considered as prime examples for power-law-like frequency distributions, yet there is no agreement on the mechanisms responsible for the observed patterns. Our model suggests that instead of a single unified distribution, a superposition of at least two different distributions can be detected and this suggests multiform mechanisms acting on different scales. None of the discovered distributions are compatible with the power-law hypothesis. [ABSTRACT FROM AUTHOR]

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Plant roots interact with a bewilderingly complex community of microbes, including root-associated fungi that are essential for maintaining plant health. To improve understanding of the diversity of fungi in the rhizobiome of Populus deltoides, Populus trichocarpa and co-occurring plant hosts Quercus alba and Pinus taeda , we conducted field and greenhouse studies and sampled, isolated, and characterized the diversity of culturable root-associated fungi on these hosts. Using both general and selective isolation media we obtained more than 1800 fungal isolates from individual surface sterilized root tips. Sequences from the ITS and/or D1– D2 regions of the LSU rDNA were obtained from 1042 of the >1800 pure culture isolates and were compared to accessions in the NCBI nucleotide database and analyzed through phylogenetics for preliminary taxonomic identification. Sequences from these isolates were also compared to 454 sequence datasets obtained directly from the Populus rhizosphere and endosphere. Although most of the ectomycorrhizal taxa known to associate with Populus evaded isolation, many of the abundant sequence types from rhizosphere and endosphere 454 datasets were isolated, including novel species belonging to the Atractiellales. Isolation and identification of key endorrhizal fungi will enable more targeted study of plant-fungal interactions. Genome sequencing is currently underway for a subset of our culture library with the aim of understanding the mechanisms involved in host-endophyte establishment and function. This diverse culture library of fungal root associates will be a valuable resource for metagenomic research, experimentation and further studies on plant-fungal interactions. [ABSTRACT FROM AUTHOR]

Classification of phenotypic variability in forest dwelling arthropods, especially in applied bioindication, remains difficult due to the complex and synergic ecological interactions. Ecologically, it corresponds with the concept of alternative ontogenies in order to maintain high population fitness. The research on the geobiont Haplothrips subtilissimus (Thysanoptera: Phlaeothripidae) morphometric plasticity alongside selected ecological gradients (temperature, humidity, food availability) and the environmental impact in the xerothermous hilly oak wood (Martinský les, SW Slovakia), have revealed that (MAN(C)OVA and Kruskal–Wallis test) the head width ( p < 0.001) and anterior pronotum width ( p ≤ 0.002) as the only statistically significant variables. The Kruskal–Wallis test (non parametric ANOVA) revealed significant variation (more noticeable in males) in ecologically more diverse ecotone stands. A significant correlation ( p < 0.001) could be shown between the morphometric parameter pairs “head width” and “anterior pronotum width” for both sexes (0.729 for females and 0.822 for males) and between anterior and posterior pronotum width only for males (0.859). Pillai's statistics revealed an interaction of soil humidity and soil temperature which confirms female body parameters depend on habitat conditions ( p = 0.011). Females responded mainly to soil temperature ( p = 0.018) and food availability ( p = 0.030). Soil humidity interacts with the male's morphology (soil humidity p = 0.040), while the relationship to food availability (Acarina) was not statistically significant ( p = 0.350). No body parameter has been significantly affected by environmental stress. [ABSTRACT FROM AUTHOR]

In this study, we hypothesized that a positive impact of Acacia trees when grown in mixed stands with Eucalyptus trees in N-deficient soil, leads to a higher biomass production in mixed stands relative to the monocultures. A randomized block design experiment was set up in a Brazilian Planosol to assess the dynamics of aboveground accumulation of monospecific Eucalyptus urograndis ( Eucalyptus urophylla S. T. Blake × Eucalyptus grandis W. Hill ex Maiden), with or without nitrogen fertilization (E100 + N and E100, respectively), and Acacia mangium (A100) stands, and two arrangements of both species in mixed plantations (E50A50 and E100A100). The height ( H ), diameter at breast height (DBH), litterfall, and aboveground biomass production were measured over a full rotation. Our results partially confirm the initial hypothesis. Acacia showed limited competitive ability against Eucalyptus , which resulted in a stratified canopy in the mixed stands, with Eucalyptus dominating the top layer, especially in the E100A100 arrangement. The E100A100 stand showed greater overall productivity compared with the E100 stand and similar productivity relative to the E100 + N stand. The E50A50 arrangement produced taller Eucalyptus trees with a larger diameter than the monoculture, although the smaller population of Eucalyptus trees in this mixed stand resulted in an overall biomass production that was equal to or less than that of the monocultures E100 and E100 + N, respectively. However, the DBH growth rate of Eucalyptus trees in E50A50 showed no signs of stagnation up to 60 months, which is different from the other treatments. Consequently, the harvesting age of such stands can be extended, which allows for the production of Eucalyptus logs with greater value for the lumber market. [ABSTRACT FROM AUTHOR]

• Interactions between over- and understorey do not reduce to light pre-emption by the overstorey. • Besides light interception, overstorey controls the development of understorey vegetation by belowground competition. • In turn, understorey drives overstorey development by sharing belowground resources and common mycorrhizal networks. • Drought stress alleviation and nutrient sharing by mycorrhizae rely mostly on overstorey-driven processes. • Large mammalian herbivores modulate below- and aboveground resource sharing through complex indirect interactions. Plant interactions play a key role in forest ecosystem dynamics. The tallest plants, namely the overstorey trees, are obvious major drivers, particularly in competition for light. This process has already been amply described. However, the role played by lower strata has often been underestimated. In this review, we first briefly recall the role of over- and understoreys in structuring forest microclimate, mostly through light sharing. We then focus on belowground interactions between over- and understorey, where knowledge is more piecemeal, partly because of measurement difficulties. Even so, some studies show that competition for water and nutrients by the overstorey controls the development of understorey vegetation much more than competition for light. The reverse (overstorey limitation by the understorey) has also been encountered, but has been much less well researched. We also address the involvement of mycorrhizae, specifically their role in alleviating overstorey drought stress and contributing to nutrient cycling. We go on to show how another example of key ecosystem engineers, large mammalian herbivores, shape above- and belowground resources and intervene in over- and understorey interactions. In conclusion, for a better understanding of forest dynamics and adapted management, particularly in the context of global climate change, we advocate taking account not only of trees but of all forest components. Belowground processes need more research. The roles of mycorrhizal networks, root exudates, microbiota, and chemical cues need to be further explored to gain a finer understanding of the interactions between over- and understorey. [ABSTRACT FROM AUTHOR]

[Display omitted] • SMS composting effectively influence the microbial dynamic. • Microbial networks are modularized and fragmented. • Network topological properties are significantly influenced by environmental factors. • The final composting product are mature, safe and available. Global mushroom production is growing rapidly, raising concerns about polluting effects of spent mushroom substrate (SMS) and interest in uses in composts. In this study, SMS composting trials and high-throughput sequencing were carried out to investigate to better understand how the structure, co-occurrence patterns, and functioning of bacterial and fungal communities vary through compost time and across environmental conditions. The results suggested that both bacterial and fungal microbiota displayed significant variation in community composition across different composting stages. Enzyme activity levels showed both directional and fluctuating changes during composting, and the activity dynamics of carboxymethyl cellulase, polyphenol oxidase, laccase, and catalase correlated significantly with the succession of microbial community composition. The co-occurrence networks are "small-world" and modularized and the topological properties of each subnetwork were significantly influenced by the environmental factors. Finally, seed germination and seedling experiments were performed to verify the biosafety and effectiveness of the final composting products. [ABSTRACT FROM AUTHOR]

Understanding the processes that underlay an ecological disaster represents a major scientific challenge. Here, we investigated phytoplankton and zooplankton community changes before and during a fauna mass kill in a European protected wetland. Evidence on gradual development and collapse of harmful phytoplankton blooms, allowed us to delineate the biotic and abiotic interactions that led to this ecological disaster. Before the mass fauna kill, mixed blooms of known harmful cyanobacteria and the killer alga Prymnesium parvum altered biomass flow and minimized zooplankton resource use efficiency. These blooms collapsed under high nutrient concentrations and inhibitory ammonia levels, with low phytoplankton biomass leading to a dramatic drop in photosynthetic oxygenation and a shift to a heterotrophic ecosystem phase. Along with the phytoplankton collapse, extremely high numbers of red planktonic crustaceans- Daphnia magna , visible through satellite images, indicated low oxygen conditions as well as a decrease or absence of fish predation pressure. Our findings provide clear evidence that the mass episode of fish and birds kill resulted through severe changes in phytoplankton and zooplankton dynamics, and the alternation on key abiotic conditions. Our study highlights that plankton-related ecosystem functions mirror the accumulated heavy anthropogenic impacts on freshwaters and could reflect a failure in conservation and restoration measures. [Display omitted] • A mass fauna kill followed changes in plankton dynamics and abiotic factors. • Blooms of harmful phytoplankton species blocked biomass flow in the lake's food web. • High ammonia levels led to phytoplankton collapse and drop of photosynthetic oxygen. • Extremely high numbers of red Daphnia individuals were visible through satellites. • Disclosure of the mass fauna kill was observed due to water level decrease. [ABSTRACT FROM AUTHOR]

Predicted climate change scenarios for the end of this century suggest a substantial warming and ocean acidification of sea surface waters. Physiological performance of marine coastal organisms will be affected leading to changes in whole communities. In particular, ocean acidification poses an important threat for shelled molluscs. Nevertheless, climate change impacts are species-specific and responses may even differ among species that play a similar role in the ecosystems. Currently, two mussel species, the native Mytilus galloprovincialis Lamarck 1819 and the non-indigenous Xenostrobus securis Lamarck 1819, share the same habitat along shores in the inner part of the Galician Rias Baixas (NW Spain) forming mixed patchy clumps. Here, we used an experimental approach in mesocosms to evaluate the effects of increasing temperature and acidification on mussel clumps of different composition (monospecific and mixed clumps). Our model systems were artificially constructed clumps resembling those found on rocky shores. Responses to environmental stressors were measured on several functioning variables at the individual (i.e. survivorship, growth, condition index and composition of shell) and clump level (i.e. respiration, ammonia and phosphate excretion rates). The decrease of pH had a lethal effect and reduced growth on the native mussels. The invader was more resilient although individual responses were very often shaped by the composition of the clump. The reduced pH and, especially the high temperature conditions, tended to cause an increase in respiration rates of all types of clumps. Interactions between the two species seemed to modulate many effects at both individual and clump levels highlighting the complexity of responses when considering multiple stressors. [ABSTRACT FROM AUTHOR]

The application of ionomics and ecological stoichiometry benefits conservation biology with necessary ecological and evolutionary relevance, allowing unresolved problems to be addressed. The use of ionomics and ecological stoichiometry enables consideration that changes in the environmental nutritional supply affect the ecophysiology, behavior, health and fitness of individuals, influencing their ecological interactions and population functioning. The resulting knowledge can help promote better conservation and restoration strategies. Ultimately, ionomics and ecological stoichiometry facilitate improved forecasting and mitigation of the negative effects of current global change. Here, we present the theoretical background followed by the application of ionomics and ecological stoichiometry in biological conservation. We also propose avenues for future research. For example, larval and adult pollinating insects belong to different feeding guilds, and larvae rely on various stoichiometrically (im)balanced foods (showing herbivory, pollinivory, detritivory or even carnivory). Therefore, the ecology and diversity of pollinators may be shaped by the nutritional quality of larval food, which is required for physiological development into fully functional adults. Although a stoichiometric balance during larval development is crucial for pollinator health and fitness, pollinator conservation is focused on the nutritional needs of adults. Another example is atmospheric CO 2 increases leading to nutrient dilution in plant tissues, aggravating nutritional imbalances in consumers and challenging Earth's herbivore populations. CO 2 -driven nutrient dilution may affect food webs, ecosystems and human wellbeing. However, our understanding of this phenomenon is minimal. These and other unresolved conservation biology problems may be studied and solved using ionomics and ecological stoichiometry. • Biogeochemical processes affect our biological conservation efforts. • Ecological stoichiometry and ionomics may be used in conservation biology. • This brings research closer to nature and offers tools for asking important questions. • We present examples of pollinator conservation and CO 2 driven nutrient dilution. [ABSTRACT FROM AUTHOR]

Highlights: [•] Individual behavior is integral to the organization of ecological systems. [•] Automated image-based tracking offers novel opportunities to study behavior. [•] Tracking data allows linking individual to higher-level ecological processes. [•] A diverse range of taxa have now been tracked in a variety of habitats. [•] Automated image-based tracking has an important role in ecology. [ABSTRACT FROM AUTHOR]

Effects of three biocides, esfenvalerate, picoxystrobin and triclosan, were studied in a Soil-Multi-Species (SMS) test system with four springtail- and one earthworm species exposed for eight weeks. All biocides affected springtail population growth negatively, and species- and chemical specific differences had clear impacts on their dominance structure. We suggest that differences in vulnerability may be influenced by activity related to species-specific vertical distribution in the soil. The responses of the springtail Folsomia fimetaria differed strongly from previous results from a single-species experiment with the same biocides. Survival of juvenile earthworms was more sensitive to biocide exposure than weight gain, and earthworm performance was significantly correlated with springtail abundance. Feeding activity of soil organisms measured with the bait lamina test system was a sensitive criterion for esfenvalerate and picoxystrobin exposure, but not for triclosan. The results suggest that interspecific interactions such as resource- and interference competition may influence the toxicity of biocides. SMS test systems may hence be a suitable method for investigating direct and indirect effects in combination under standardized laboratory conditions. [ABSTRACT FROM AUTHOR]

Species interactions such as predation or competition can have notable implications for fish population dynamics. Stock status and associated biological reference points can be misrepresented if these interactions are not considered. Here we present a multispecies, biomass production model (MS-PROD) developed by incorporating modifications to the Schaefer production model. The modifications explicitly emphasize a functional group approach, highlighting the effects of species interactions that include competition between species within a group, competition between groups, and predation. The mathematical formulation also includes constraints on carrying capacity for both the entire system and for individual groups. We applied the model as initialized to the Northeast U.S. Large Marine Ecosystem finfish community. We then executed simulations designed to explore the behavior of the model with respect to fishery exploitation and ecological interactions. Collectively, the results demonstrated the utility, and the need, for incorporating ecological effects into fisheries models. [Copyright &y& Elsevier]

We conducted a short-term field sampling complemented with time integrating stable isotope analysis to holistically investigate status and ecological interactions in a remote NE Atlantic Zostera marina meadow. We found high nutrient water concentrations, large biomass of fast-growing, ephemeral macroalgae, low abundance, and biodiversity of epifauna and a food web with thornback ray (Raja clavata) as intermediate and cod (Gadus morhua) as top predator. We observed no variation with increasing depth (3.5–11 m) except for decreasing shoot density and biomass of Zostera and macroalgae. Our results indicate that the Finnøya Zostera ecosystem is eutrophicated. During the past three to four decades, nutrients from aquaculture have steadily increased to reach 75% of anthropogenic input while the coastal top predator cod has decreased by 50%. We conclude that bottom-up regulation is a predominant driver of change since top-down regulation is generally weak in low density and exposed Zostera ecosystems such as Finnøya. • Zostera marina species components • Water and sediment biogeochemistry • Ecological interactions • Aquaculture and fishery • NE Atlantic [ABSTRACT FROM AUTHOR]

Soil ecology is witnessing exponential growth in the number of studies using co-occurrence network analysis. Researchers reconstruct networks based on the co-occurrence of taxa or genes across soil samples at a wide range of geographic scales - from single aggregates to the whole planet - and taxonomic scopes, some studies targeting specific taxa or guilds to others surveying the whole microbiome as well as micro- and mesofauna. Co-occurrence networks can be very useful to extract simple patterns from complex datasets. Applications include the detection of abiotic and biotic factors that determine community structure, the identification of keystone taxa and their relationship to specific soil functions, and the inference of mechanisms of community assembly. However, networks are more and more often misused and serve as mere graphic tools with no attempt at hypothesis testing. In this perspectives article, we first review the main usage of co-occurrence network analysis in soil ecology during the last decade. We then discuss the applications and caveats of network analysis in soil ecology, leaving apart strictly methodological aspects of network reconstruction, which is beyond the focus of this article. Finally, we include recommendation guidelines – such as the possibility of informing networks with geographic, environmental and/or phylogenetic information – with the hope that this will facilitate network analysis to become a useful tool that helps elucidate meaningful patterns in soil ecology. •Number of articles using co-occurrence network analysis has grown exponentially •Review usage and applications of networks in soil ecological communities •Detect main pitfalls and misuse of co-occurrence networks •Provide guidelines to extract meaningful ecological patterns from networks [ABSTRACT FROM AUTHOR]

Abstract: Interactions between plants, soils and microbes regulate terrestrial ecosystem functioning. Biotic and abiotic interactions can strongly affect the community structure which in turn will impact on ecological processes. Plant species with different ecophysiological traits can exert strong effects on soil biological properties. Our objective was to investigate and identify the effects of different biotic and abiotic variables on soil microbial community structure and functions and to examine if plant species with different physiological traits support different microbial communities in soils. Here, we show that 3 years of the presence of plants had direct impacts on soil function in terms of total heterotrophic respiration and on microbial biomass and microbial community structure. However, the plant species-specific impact on bacterial community structure was weak, and differences were mainly driven by sample field location. The fungal community analysis gave similar results, with soil location being the most important factor driving fungal community structure. The effect of plant species on fungal community structure was weak but statistically significant. There was a strong concordance between bacterial and fungal communities (P <0.001) which suggested that the bacteria and fungi have an influence on shaping the structure of each other''s community. Among the abiotic factors, moisture had a comparatively higher impact on bacterial communities compared to soil N and C. However, the fungal community was not affected by the soil moisture but soil N and C had a stronger impact than on the bacterial community. These results indicate that the microbial community structure in the natural environment is influenced by interactions between both biotic and abiotic factors. [Copyright &y& Elsevier]

Motile bacteria sense changes in the concentration of chemicals in environments and respond in a behavioral manner. This behavioral response is called chemotaxis. Bacterial chemotaxis can be viewed as an important prelude to metabolism, prey–predator relationships, symbiosis, infections, and other ecological interactions in biological communities. Genome analysis reveals that a large number of environmental motile bacteria possess a number of genes involved in chemosensing and chemotatic signal transduction. Pseudomonas aeruginosa has a very complex chemosensory system with more than 20 chemotaxis (che) genes in five distinct clusters and 26 chemoreceptor (methyl-accepting chemotaxis protein [mcp]) genes. Among the 26 MCPs of P. aeruginosa, nine have been identified as MCPs for amino acids, inorganic phosphate, oxygen, ethylene, and volatile chlorinated aliphatic hydrocarbons, whereas 3 MCPs were demonstrated to be involved in biofilm formation and biosynthesis of type IV pilus. Six che genes are essential for chemotactic responses, while genes in Pil-Chp cluster and Wsp cluster are involved in type IV pilus synthesis and twitching motility and biofilm formation, respectively. P. aeruginosa, with its complex chemotaxis system, is a better model microorganism for investigating ecological aspects of chemotaxis in environmental bacteria than Escherichia coli and Salmonella enterica serovar Typhimurium, which possess a relatively simpler chemotaxis system. [Copyright &y& Elsevier]

Abstract: The species sensitivity distribution, a technique currently used to derive water-quality standards of chemicals, is associated with a set of inadequately tested assumptions. One of these assumptions is that ecosystem structure is as or more sensitive than ecosystem function, i.e., that structure is the target of concern. In this paper, we tested this assumption for a simple freshwater ecosystem exposed to different toxicants. Using an ecosystem model, we calculated no observed effect concentrations (NOECs) for ecosystem structure (ecosystem structure-NOECs) and function (ecosystem function-NOECs) for each of 1000 hypothetical toxicants. For 979 of these toxicants, the ecosystem structure-NOEC was lower than or equal to the ecosystem function-NOEC, indicating that the tested assumption can be considered valid. For 239 of these 979 toxicants, both NOECs were equal. For half of the 1000 toxicants, the structure of lower trophic levels (i.e., phytoplankton) appears to be more sensitive than the structure of higher trophic levels (i.e., fish). As such, ecosystem structure-NOECs are primarily determined by the sensitivity of the structure of lower trophic levels. In contrast, ecosystem functions associated with higher trophic levels (e.g., total ingestion by fish) are more sensitive than functions associated with lower trophic levels (e.g., total photosynthesis by phytoplankton) for 749 toxicants. [Copyright &y& Elsevier]

This study describes assemblages of predatory ground beetles in native birch forest and derived blueberry farms on the Lower Mainland of British Columbia and investigates their role in the successful biological control of winter moth (Operopthera brumata L.) by the parasitoid Cyzenis albicans Falle´n. Pitfall traps at four sites in 1991 and 1992 indicated that natural birch forest was dominated by native carabid species, while open blueberry was dominated by introduced species and some native xerophilous species. Predation by generalist invertebrates was an important mortality factor for both winter moth and C. albicans at all sites and was greatest in the first 2 weeks after pupation. Ground beetles including Harpalus affinus (Schrank) and Pterostichus spp. consumed winter moth pupae in arenas but adult beetles rarely consumed C. albicans pupae. Much of the overall predation was due to smaller invertebrates including beetle larvae. Predators actively searched for buried pupae and selected among pupal types based on condition (dead, parasitised or healthy) and size. Prey-selection differed among sites but C. albicans pupae were preferred at three of the four sites. At the remaining site, an organic blueberry farm, over 90% of both parasitised and healthy pupae were consumed. High levels of predation did not affect the levels of parasitism by C. albicans at the sites. This herbivore–parasitoid–predator system demonstrates the importance of naturally occurring predatory invertebrates for successful integrated pest management, even where they prey upon a biological control agent. [Copyright &y& Elsevier]

The abundance of heterotrophic flagellates, ciliates and naked amoebae was measured in 8 sites covered with different vegetation (beech, birch, beech-birch, birch-oak-beech, grass) from January to April 2001. The results were analysed by a suite of mathematical techniques, together with data on bacteria, fungi, nematodes, microarthropods, and the composition of forest litter and field layer, available from parallel research. The population levels ranged between 4.02 and 795 × 103, 28 and 1010, 35 and 1170 g–1 litter dry wt for flagellates, ciliates and amoebae, respectively. Temporal changes in the microbiota appeared to be affected by progressive winter cooling followed by a spring increase in temperature, and influenced by habitat characteristics and a complex multivariate interplay among ecosystem components. The population abundance in winter (January-mid March) was higher than in spring (late March–April) for all protozoa. Amoebae showed minimum values in March, followed by considerable recovery in April. However, ciliate values dropped slightly between March and April, whilst flagellate values steadily decreased throughout the whole research period, suggesting that the spring growth of ciliates and flagellates might have been arrested by increased predation and/or competition. Statistical analysis revealed a number of significant relationships between the protozoa studied and other ecosystem components. These relationships were indicative of the conditions studied and may, therefore, be useful for future reference. The results highlighted the complexity of transient multivariate interactions of protobiota in forest litter, suggesting that any interpretations of the population dynamics must take account of a full range of both temporal and spatial factors. [Copyright &y& Elsevier]

In México, the unique living member of the genus Canis Linnaeus, 1758, is the coyote (C. latrans Say, 1823). The wolf (C. lupus Linnaeus, 1758) is not considered because it is a recently reintroduced species. Not much is known about the biology and evolution of the coyote in the Mexican territory. However, the fossil record allows us to compare between the living and past members. The aim of this work is to evidence the variation in size of the teeth of the Pleistocene coyote with respect to living populations from México. For this research, we use dental material of specimens housed at paleontological and mastozoological collections. In the results, we observed a reduction in the size of all dental elements of the current coyotes with respect to the Pleistocene ones. In the case of the first upper molar (M1), the reduction is significant. The reduction in the size of skeletal elements in C. latrans has been reported in other studios. The dental narrowing observed in this canid is probably a reflection of an alteration in the diet of this mammal, as has been observed in other mammals carnivores with a similar evolutionary history (e.g., Panthera onca). • Decrease in the size of C. latrans is a consequence of alteration in diet. • We observed differences between the size of the teeth. • Teeth showed a reduction in size. • Implies a higher consumption of meat in the diet of the Pleistocene coyotes. [ABSTRACT FROM AUTHOR]

• There is temporal consistency in the rules assembling plant-frugivore networks. • Species' traits explain the frequency of pairwise interactions. • Models including species' relative abundances drive the general structure of seasonal networks. There is an ongoing debate on whether species' traits or neutrality generate recurrent patterns of mutualistic networks. Although there have been recent advances on the issue, many studies neglect the seasonal dynamics of these drivers. In this study, we investigated how pervasive are the drivers (i.e. species' size, phenological overlap and species relative abundance) of the frequency of pairwise interactions and the aggregate metrics of seasonal seed dispersal networks in a semideciduous forest from the savannahs of Southeastern Brazil. We used a likelihood approach and built probability matrices based on different drivers to compare how they fit in the frequency and structure of the seasonal observed networks. We found that in both seasons trait-based processes, especially phenological overlap between species, best predicted the frequency of pairwise interactions. However, species relative abundances performed better than species traits in explaining most of aggregate network metrics in both seasons, except for the interaction evenness. These findings suggest that ecological and evolutionary processes are seasonally pervasive and determine the ability of species to interact with their partners. Besides, the general structure of the seasonal networks is less sensitive to species traits and its drivers remain seasonally constant. We conclude that our ability to understand the complexity of plant-frugivore interactions depends on assessing the contribution of species traits and their relative abundances to the structure of seasonal-detailed networks. Image, graphical abstract [ABSTRACT FROM AUTHOR]

The bacterial genus, Borrelia , is comprised of vector-borne spirochete species that infect and are transmitted from multiple host species. Some Borrelia species cause highly-prevalent diseases in humans and domestic animals. Evolutionary, ecological, and molecular research on many Borrelia species have resulted in tremendous progress toward understanding the biology and natural history of these species. Yet, many outstanding questions, such as how Borrelia populations will be impacted by climate and land-use change, will require an interdisciplinary approach. The evolutionary ecology research framework incorporates theory and data from evolutionary, ecological, and molecular studies while overcoming common assumptions within each field that can hinder integration across these disciplines. Evolutionary ecology offers a framework to evaluate the ecological consequences of evolved traits and to predict how present-day ecological processes may result in further evolutionary change. Studies of microbes with complex transmission cycles, like Borrelia, which interact with multiple vertebrate hosts and arthropod vectors, are poised to leverage the power of the evolutionary ecology framework to identify the molecular interactions involved in ecological processes that result in evolutionary change. Using existing data, we outline how evolutionary ecology theory can delineate how interactions with other species and the physical environment create selective forces or impact migration of Borrelia populations and result in micro-evolutionary changes. We further discuss the ecological and molecular consequences of those micro-evolutionary changes. While many of the currently outstanding questions will necessitate new experimental designs and additional empirical data, many others can be addressed immediately by integrating existing molecular and ecological data within an evolutionary ecology framework. [ABSTRACT FROM AUTHOR]

The direct effects of large-scale disturbances are readily studied because their effects are often apparent and result in large changes to ecosystems. Direct effects can cascade through the ecosystem, leading to indirect effects that are often subtle and difficult to detect. Managing anthropogenic disturbances, such as chemical contamination, requires an understanding of both direct and indirect effects to predict, measure, and characterize the impact. Using a replicated whole-ecosystem experiment and path analyses (assesses the effects of a set of variables on a specified outcome, similar to multiple regression), we examined the direct and indirect effects of a glyphosate-based herbicide and nutrient enrichment on wetland communities. The latter did not impact any measured endpoints. The strongest drivers of macrophyte, benthic invertebrate, and amphibian assemblages were the ephemerality and the size of wetlands, factors which were not altered by herbicide applications. The herbicide had a direct negative effect on macrophyte cover, amphibian larval abundance, and the proportion of predatory benthic invertebrates. However, both amphibians and invertebrates were positively affected by the reduction in the macrophyte cover caused by the herbicide applications. The opposing directions of the direct and indirect effects lead to no net change in either group. The compensatory dynamics observed herein highlight the need for a better understanding of indirect effects pathways to determine whether common anthropogenic disturbances alter the ecological communities in small wetland ecosystems. Unlabelled Image • Glyphosate application has a direct negative effect on wetland macrophyte cover. • The indirect effect of macrophyte reduction on the amphibian and benthic invertebrate communities opposed the direct effect. • Compensatory dynamics make it difficult to determine the overall effects of chemical contamination on wetland communities. • Natural variation in abiotic environmental factors has a greater effect on wetland communities than herbicide application. [ABSTRACT FROM AUTHOR]