29 research outputs found

    Predatory arthropod community composition in apple orchards: Orchard management, landscape structure and sampling method

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    Studies on predatory arthropods in agricultural areas seldom include Diptera other than hoverflies, partly because common sampling methods are less effective for capturing species that easily fly off when disturbed. To study the effect from this bias when describing the predator community, we compared traditional beat sampling of branches and suction sampling for describing the community of predatory arthropods in Swedish apple orchards, both organic orchards and orchards using integrated pest management (IPM). Our results indicate that the proportion of both predatory dipterans and parasitic hymenopterans increase dramatically when using suction sampling (Diptera: 32% vs. 20%, Hymenoptera: 25% vs. 7%). In fact, predatory dipterans were the most abundant predatory group when using suction sampling, in contrast to beat sampling where spiders were the most abundant group. One group of predatory flies that was particularly rich in both species and individuals in the surveyed apple orchards was dance flies in the family Hybotidae. Even though the bias of sampling method was evident, it was encouraging that the method choice did not affect the conclusions concerning management on predatory arthropod communities. With both methods, dipteran and coleopteran predators were more abundant in organic apple orchards whereas opilionids were more abundant in orchards managed according to IPM. The inclusion of landscape variables further indicated effects of landscape diversity and of deciduous forest cover, but the response varied in sign between predatory groups. Whereas both Coleoptera and Heteroptera were more abundant in orchards surrounded by more complex landscapes (high landscape diversity and/or high deciduous forest cover), spiders, opilionids and dipterans were rather less abundant in these orchards. To conclude, our study points to the potential importance of predatory dipterans in apple orchards, and we highly recommend future studies of arthropod predators in apple and other crops to actively include predatory Diptera

    Different spatial structure of plant-associated fungal communities above- and belowground

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    The distribution and community assembly of above- and belowground microbial communities associated with individual plants remain poorly understood, despite its consequences for plant-microbe interactions and plant health. Depending on how microbial communities are structured, we can expect different effects of the microbial community on the health of individual plants and on ecosystem processes. Importantly, the relative role of different factors will likely differ with the scale examined. Here, we address the driving factors at a landscape level, where each individual unit (oak trees) is accessible to a joint species pool. This allowed to quantify the relative effect of environmental factors and dispersal on the distribution of two types of fungal communities: those associated with the leaves and those associated with the soil of Quercus robur trees in a landscape in southwestern Finland. Within each community type, we compared the role of microclimatic, phenological, and spatial variables, and across community types, we examined the degree of association between the respective communities. Most of the variation in the foliar fungal community was found within trees, whereas soil fungal community composition showed positive spatial autocorrelation up to 50 m. Microclimate, tree phenology, and tree spatial connectivity explained little variation in the foliar and soil fungal communities. Foliar and soil fungal communities differed strongly in community structure, with no significant concordance detected between them. We provide evidence that foliar and soil fungal communities assemble independent of each other and are structured by different ecological processes

    The role of inputs of marine wrack and carrion in sandy-beach ecosystems: A global review

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    Sandy beaches are iconic interfaces that functionally link the ocean with the land via the flow of organic matter from the sea. These cross-ecosystem fluxes often comprise uprooted seagrass and dislodged macroalgae that can form substantial accumulations of detritus, termed ‘wrack’, on sandy beaches. In addition, the tissue of the carcasses of marine animals that regularly wash up on beaches form a rich food source (‘carrion’) for a diversity of scavenging animals. Here, we provide a global review of how wrack and carrion provide spatial subsidies that shape the structure and functioning of sandy-beach ecosystems (sandy beaches and adjacent surf zones), which typically have little in situ primary production. We also examine the spatial scaling of the influence of these processes across the broader land- and seascape, and identify key gaps in our knowledge to guide future research directions and priorities. Large quantities of detrital kelp and seagrass can flow into sandy-beach ecosystems, where microbial decomposers and animals process it. The rates of wrack supply and its retention are influenced by the oceanographic processes that transport it, the geomorphology and landscape context of the recipient beaches, and the condition, life history and morphological characteristics of the macrophyte taxa that are the ultimate source of wrack. When retained in beach ecosystems, wrack often creates hotspots of microbial metabolism, secondary productivity, biodiversity, and nutrient remineralization. Nutrients are produced during wrack breakdown, and these can return to coastal waters in surface flows (swash) and aquifers discharging into the subtidal surf. Beach-cast kelp often plays a key trophic role, being an abundant and preferred food source for mobile, semi-aquatic invertebrates that channel imported algal matter to predatory invertebrates, fish, and birds. The role of beach-cast marine carrion is likely to be underestimated, as it can be consumed rapidly by highly mobile scavengers (e.g. foxes, coyotes, raptors, vultures). These consumers become important vectors in transferring marine productivity inland, thereby linking marine and terrestrial ecosystems. Whilst deposits of organic matter on sandy-beach ecosystems underpin a range of ecosystem functions and services, they can be at variance with aesthetic perceptions resulting in widespread activities, such as ‘beach cleaning and grooming’. This practice diminishes the energetic base of food webs, intertidal fauna, and biodiversity. Global declines in seagrass beds and kelp forests (linked to global warming) are predicted to cause substantial reductions in the amounts of marine organic matter reaching many beach ecosystems, likely causing flow-on effects for food webs and biodiversity. Similarly, future sea-level rise and increased storm frequency are likely to alter profoundly the physical attributes of beaches, which in turn can change the rates at which beaches retain and process the influxes of wrack and animal carcasses. Conservation of the multi-faceted ecosystem services that sandy beaches provide will increasingly need to encompass a greater societal appreciation and the safeguarding of ecological functions reliant on beach-cast organic matter on innumerable ocean shores worldwide

    Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

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    Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

    Community heterogeneity and the evolution of interactions between plants and insect herbivores

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    Plant communities vary tremendously in terms of productivity, species diversity, and genetic diversity within species. This vegetation heterogeneity can impact both the likelihood and strength of interactions between plants and insect herbivores. Because altering plant?herbivore interactions will likely impact the fitness of both partners, these ecological effects also have evolutionary consequences. We review several hypothesized and well?documented mechanisms whereby variation in the plant community alters the plant?herbivore interaction, discuss potential evolutionary outcomes of each of these ecological effects, and conclude by highlighting several avenues for future research. The underlying theme of this review is that the neighborhood of plants is an important determinant of insect attack, and this results in feedback effects on the plant community. Because plants exert selection on herbivore traits and, reciprocally, herbivores exert selection on plant?defense traits, variation in the plant community likely contributes to spatial and temporal variation in both plant and insect traits, which could influence macroevolutionary patterns.Our research is supported by NSF DEB-0447550 (AAA, www.herbivory.com), by NSF IBN-0206601 ( JAL and SY Strauss), and by the Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (FORMAS to PAH). JAL is currently supported by NSF IOB 0620318 to P Tiffin, R Shaw, and P Reich

    Fasta file - with sequences

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    This Fasta file contains all unique sequences accompanied by a unique identification number from 1 to 9193, which corresponds to a number in the file ’Frequency table.xls

    Frequency table

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    This file tabulates sequences for all spider individuals. Each row in this file represents a unique sequence with the identification number (in column 1) corresponding to the sequence number in the file ’Fasta file – with sequences.txt’. The following columns have the following descriptions: Sequence count = the total number of sequence across all spider individuals Order = Arthropod order corresponding to the sequence Sequence identity = The identity based on best match in Barcode of Life Data bas Match = best match where 1.00 corresponds to perfect match (100%) Spindel_1 .. Spindel_504 = unique identity for each spider individual, which corresponds to a number in the file ’GutTesta.txt’. The numbers in this column indicates the number of sequences for each unique sequence and spider individua

    Tabulated gut contents

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    This file summarises presence-absences for a given prey group in the gut of a spider individual. The columns have the following descriptions: Spider no = unique identity for each spider individual, with a number corresponding to columns in the file ’Frequency table.xls’ Site = Collection site, see Figure 1 in the paper Date = Collection date Month = Collection month Identity = Identification of spider individual: ’Pardosa prativaga’, ’Pardosa agricola’, ’Pardosa sp’ Sex, f = female, m = male, x = unidentified Age, ad = adult, subad = subadult, juv = spiderling Predation events = total number of predation events Pepred = Predation events – occurrence of predator in gut Weight = Weight in mg Two group columns, Aqua = Aquatic larvae, Terr = Terrestrial larvae Nine group columns, Chir = Chironomids, Aqu = other aquatic diptera, Det = detritivores, Pred = predators, Herb = herbivores, Leps = Lepidoptera, Cole = Coleoptera, Hete = Heteroptera, Coll = Collembola 22 columns for taxonomic categories
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