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Soil pollution represents a threat to soil biodiversity and to soil and human health. However, many ecotoxicological issues, such as the impact of heavy metal pollution on the soil mite community and its spatial distribution in areas with complex environmental factors, are not fully understood. Here, an investigation was conducted in an arable area (about 11 km 2) enclosed by surrounding mountains. The study area was contaminated with potentially toxic metals derived from copper smelting that was functioning for over 10 years. The area comprised four land use types: woodlands, dry fields, paddy fields, and wastelands, and was divided into 141 study sites each with an area of 6.25 ha. The soil metal (Cu, Zn, Pb, and Cd) contents, pH, and organic matter were determined and their distributions were established. Furthermore, soil mite (Acari) community properties (species richness, individual abundance, and Shannon–Wiener diversity index) were determined, and the distributions of total species number and abundance were ascertained. Soil metal pollution strongly reduced soil mite community, but the effects depended on mite groups or species and their sensitivity to different metals as well as land use types. CANOCO analysis revealed that the order Oribatida was more highly correlated with soil metal contents, whereas the other three orders responded to soil metal contents depending on land use types, mite properties, or metals. SADIE method indicated that the coordinate relationship between mite species number and metal concentration was more negative (4–25% of the study sites) than positive (4–12%). The metal pollution levels in the soil were evaluated by single and integrated pollution and ecological risk indices.

A key to larvae of Ptychopteridae (phantom crane flies) is provided for species inhabiting Northern Europe. The key encompasses seven species, including the previously undescribed larvae of Ptychoptera longicauda (Tonnoir 1919). Larval specimens examined were primarily sampled from sites in Denmark. Larvae were associated with correctly identified adults based on DNA barcode (COI) sequence. In the development of the key, a wide suite of morphological characteristics were examined and evaluated for their utility to separate species. Current distribution maps are provided for all species occurring within Northern Europe. Based on records of larvae from Denmark and Finland, notes on larval habitats are given. We also present flight periods for all species examined during this study. Finally, the status of the enigmatic species Ptychoptera obscura (Peus 1958) is briefly discussed.

The protection of soil biodiversity is essential for ensuring soil functioning and provisioning of related ecosystem services, but also the conservation of species per se. For this purpose, it is essential to know what soil organism is where and how it is influenced by environmental, climate and human activities. Numerous studies (there are over 1400 published articles) have been elaborated in Europe regarding soil fauna. A data platform to store data on soil fauna already exists and is currently under further development to become a pan-European data warehouse for soil biodiversity (https://www.eudaphobase.eu/). Though, the data stored in this database until now comprises only a small percent of the available data. Hence, it is evident that a compiled dataset providing an overall understanding of the distribution of several taxa across European biomes and under different land use still is missing.Attempting to fill this gap, we start a new initiative within the framework of the Cost Action EUdaphobase CA18237: the creation of the first European Atlas of Soil Fauna. We aim to map, summarize and upscale the current knowledge on soil fauna to help in providing support to the scientific community and directions to stakeholders and policymakers. We seek collaboration (data holders and experts) to identify, collect and analyze data of all groups of micro-, meso- and macrofauna in Europe. This presentation will focus on the aims of this initiative and the way we plan to collect data and involve people.

Soil is a complex habitat that host an important diversity of soil organisms. The latter process soil organic matter along trophic chains that play a key role in soil functioning. While important progress has been made to decipher complex trophic interactions in soils, the role of soil animal mobility within the pore space as a determinant of food accessibility, and thus trophic interactions, remains poorly studied. Collembolans are ubiquitous microarthropods playing a pivotal role in soil food webs. We expected that collembolans colonize soil pores of equivalent dimension to their body size (few hundred microns). In these pores, they may hide from predators and access food resources, notably microbes. However, experimental evidences of the range of soil pores accessible to Collembola, and how it affects their mobility are missing. We used self-designed 3D printed physical pore simulation models with pore cylinders of 0.5, 0.75, 1 and 3 mm diameter (and all 4 mm long) to test how the pore diameter affects the mobility of six collembolan species (Heteromurus nitidus, Sinella curviseta, Folsomia candida, Ceratophysella denticulata, Protaphorura fimata and Mesaphorura macrochaeta). For each species, 10 individuals were placed in the soil pore simulation model at moist and dark conditions, and their ability to pass through pores was assessed after 7.5 minutes of incubation. We observed that collembolan mobility increased with pore diameter (P < 0.001), but this varied among species (P < 0.001). Species with the largest body size, namely H. nitidus (body width 0.58 ± 0.29 mm) and C. denticulata (body width 0.50 ± 0.12 mm) were particularly restricted with less than 1% of the individuals passing through pore necks of 0.4 mm. As the pore neck diameter increased, passage increased more for C. denticulata than for H. nitidus. Only 46 ± 20 % of the individuals of H. nitidus passed through a pore neck of 1 mm, whereas for C. denticulata it was 76 ± 10 %. Across the different pore diameters, P. fimata (body width 0.36 ± 0.08 mm) was the least restricted species, with 76 ± 18 % of individuals passing through pores of 0.4 mm diameter. M. macrochaeta (body width 0.11 ± 0.07 mm), S. curviseta (body width 0.39 ± 0.26 mm) and F. candida (body width 0.31 ± 0.09 mm) showed intermediate restriction in mobility with 54 ± 28 %, 43 ± 19 % and 43 ± 28 % of the individuals passing through pore of 0.4 mm diameter, respectively. At a pore diameter of 1 mm, these proportions raised to 84 ± 20%, 79 ± 10% and 95 ± 5%, respectively. Overall, Collembolan species were able to enter pores 20 ± 37 - 171 ± 33 µm wider than their body width, suggesting different ability to enter narrow pores depending on species. We conclude that the dimension of the pore diameter is a main factor restricting the mobility of collembolans in soil and presumably functions as main determinant of food accessibility.

Soil ecosystems, and the fauna they host, are known to provide many services and communities of Collembola can be used as bioindicators of soil functionality. Climate change is often expected to threaten Collembola, however, it is possible that it could also favour them. Previous studies have shown that the structure of collembolan communities can be shaped by long-term adaptation to climate, and that temperature plays a major role in the variation of species traits. In this study, we evaluated how the functional composition and structure of collembolan communities are impacted by climate change using an experimental climate manipulation design. The study used data from the CLIMAITE experiment, which was carried out in Denmark in an unmanaged heath/grassland ecosystem that was subjected to the simulated predicted climate for the year 2075. The climate manipulation experiment parameters included elevated temperature, elevated concentration of atmospheric CO 2 and extended drought, which were tested alone and in combination on a total of 48 plots, including controls. Collembola were sampled using 10-cm-depth soil cores after 1, 2 and 8 years of climate manipulation. We posited (i) that a stimulating factor (elevated CO 2) would increase mean body length, and (ii) that an inhibiting factor (drought) would favour traits indicating a euedaphic life or an ability to present resistance mechanisms (scales, ecomorphosis) and would reduce functional structure indices through environmental filtering. The results did not support these hypotheses. While the findings showed sporadic effects of the climatic treatments on the functional composition and structure, they did not demonstrate any general community response pattern. This may be due to limitations of the study in terms of climatic intensity or community assembly, opening perspectives for future experiments in terms of the choice of traits and measurements.

Conventional identification based on morphology is today's tool of choice for monitoring earthworm diversity. However, it requires skills to distinguish specific features, which can become the bottleneck in soil ecological studies. DNA-based metabarcoding is increasingly used to monitor diversity of soil organisms. Few studies have compared this method with conventional methods. The aim of the study was to compare metabarcoding based on the mitochondrial 16S rRNA region with conventional morphology-based identification, where metabarcoding captured more species (eight) than identified by conventional method (five). Additionally, we tested the effects of two commercial DNA extraction kits: PowerSoil based on 0.25 g of soil and PowerMax based on 10 g of soil (both from Qiagen), where the PowerMax covered higher richness than PowerSoil.

Earthworms are known for their important role in soil ecosystem functioning and are used as indicators of ecosystem health. Earthworms and soil microorganisms are major players in soil ecosystem processes. However, understanding of their interactions is limited. Using microcosms, we studied the effect of earthworms on soil microorganisms in entire soil mesocosms by comparing soil with and without earthworms. Soil microbial activity was determined by an extracellular enzyme activity assay, while soil DNA was used to determine prokaryote abundance by quantitative PCR targeting 16S rRNA genes and community composition and diversity by amplicon sequencing of 16S rRNA genes. The microbial activity showed an indication of increase of chitinase, α-glucosidase, β-glucosidase and endo-β-glucanase during incubation with a specific increase in endo-β-glucanase activity in the presence of earthworms. Importantly earthworms decreased species richness (p = 0.002) and were a significant factor (p = 0.008) in shaping soil prokaryotes community structure. Moreover, our results revealed enrichment of bacterial phyla of Bacteroidetes and Proteobacteria, as well as reduction in relative abundance of the archaeal phylum Thaumarchaeota, suggesting that the presence of earthworms favors specific microbes in soil. Further, differential abundance analysis showed strong correlations between enzymatic activities (all tested except phosphomonoesterase) and relative abundances of specific bacterial OTUs. Our findings suggest that earthworms influence the soil microbial communities and their activity in soil, and hence earthworm-prokaryote interactions should be incorporated in future soil microbiome studies.

Tolerance to thermal extremes is critical for the geographic distributions of ectotherm species, many of which are probably going to be modified by future climatic changes. To predict species distributions it is important to understand the potential of species to adapt to changing thermal conditions. Here, we tested whether the thermal tolerance traits of a common freeze-tolerant potworm were correlated with climatic conditions and if adaptation to extreme cold constrains the evolutionary potential for high temperature tolerance. Further, we tested if evolution of thermal tolerance traits is associated with costs in other fitness traits (body size and reproduction). Lastly, we tested if slopes of temperature-survival curves (i.e., the sensitivity distribution) are related to tolerance itself. Using 24 populations of the potworm, Enchytraeus albidus Henle (Enchytraeidae), collected from a wide range of climatic conditions, we established a common garden experiment in which we determined high and low temperature tolerance (using survival as endpoint), average reproductive output and adult body size. Heat tolerance was not related to environmental temperatures whereas lower lethal temperature was about 10 °C lower in Arctic populations than in populations from temperate regions. Reproduction was not related to environmental temperature, but was negatively correlated with cold tolerance. One explanation for the trade-off between cold tolerance and reproduction could be that the more cold-hardy populations need to channel energy to large glycogen reserves at the expense of less energy expenditure for reproduction. Adult body size was negatively related to environmental temperature. Finally, the slopes of temperature-survival curves were significantly correlated with critical temperature limits for heat and cold tolerance; i.e., slopes increased with thermal tolerance. Our results suggest that relatively heat-sensitive populations possess genetic variation, leaving room for improved heat tolerance through evolutionary processes, which may alleviate the effects of a warmer future climate in the Arctic. On the other hand, we observed relatively narrow sensitivity distributions (i.e., less variation) in the most heat tolerant populations. Taken together, our results suggest that both cold and heat tolerance can only be selected for (and improved) until a certain limit has been reached.

1. The ongoing climate change may strongly impact soil biodiversity with cascading effects on the processes they drive. Thus, it is of prime interest to improve our knowledge about responses by soil organisms such as collembolans to expected shifts in environmental conditions by considering communities comprising both detritivores and predators.2. The aim of the present study was to evaluate how simulated climate change and predation under laboratory conditions alter a collembolan community.3. To infer the impact of climate change, we applied a decreased level of soil moisture (60% vs. 30% soil water holding capacity) and an increasing air temperature (15 degrees C vs. 25 degrees C) to a collembolan community constituted by four species (Folsomia candida, Protaphorura fimata, Proisotoma minuta and Mesaphorura macrochaeta) exhibiting distinct functional traits, for example, body size and furca presence, in the presence or absence of a predatory gamasid Acari Stratiolaelaps scimitus during 2 months in a microcosm experiment.4. We observed that decreasing soil moisture altered the collembolan community with species-specific responses. Interaction between soil moisture, temperature and predation indicates that low soil moisture reduced total collembolan abundance especially (a) by suppressing the positive effect of increasing temperature and (b) by increasing the predatory control on collembolan abundance.5. These results highlight that soil moisture is the major driver of Collembola community and by consequence, a shift in climatic parameters with the ongoing climate change should strongly modify the Collembola community structure and the predator-prey interaction. Our findings are highly important since a strengthening of predation impact on Collembola prey could have major consequences on the whole soil food web being able to lead to a slowdown of key ecosystem processes they drive (e.g. litter decomposition and nutrient recycling). Finally, our study promotes the need to study more complex systems considering distinct soil-dwelling species, their functional traits and their trophic interactions to better predict the ecosystem responses to the ongoing climate change.

Trophic regulation of microbial communities is receiving growing interest in soil ecology. Most studies investigated the effect of higher trophic levels on microbial communities at the bulk soil level. However, microbes are not equally accessible to consumers. They may be hidden in small pores and thus protected from consumers, suggesting that trophic regulation may depend on the localization of microbes within the soil matrix. As microaggregates (< 250 µm) usually are more stable than macroaggregates (> 250 µm) and embedded in the latter, we posit that they will be less affected by trophic regulations than larger aggregates. We quantified the effect of four contrasting species of collembolans (Ceratophysella denticulata, Protaphorura fimata, Folsomia candida, Sinella curviseta) on the microbial community composition in macro- (250 µm – 2mm) and microaggregates (50 – 250 µm). To do so, we re-built consumer-prey systems comprising remaining microbial background (post-autoclaving), fungal prey (Chaetomium globosum), and collembolan species (added as single species or combined). After three months, we quantified microbial community composition using phospholipid fatty acid markers (PLFAs). We found that the microbial communities in macroaggregates were more affected by the addition of collembolans than the communities in microaggregates. In particular, the fungal-to-bacterial (F:B) ratio significantly decreased in soil macroaggregates in the presence of collembolans. In the microaggregates, the F:B ratio remained lower and unaffected by collembolan inoculation. Presumably, fungal hyphae were more abundant in macroaggregates because they offered more habitat space for them, and the collembolans reduced fungal abundance because they consumed them. On the contrary, microaggregates presumably contained microbial communities protected from consumers. In addition, collembolans increased the formation of macroaggregates but did not influence their stability, despite their negative effect on fungal abundance, a well-known stabilizing agent. Overall, we show that trophic interactions between microbial communities and collembolans depend on the aggregate size class considered and, in return, soil macroaggregation is affected by these trophic interactions.

The ongoing debate about the ecological effects of Bt-crops calls for thorough reviews about the impact on soil biodiversity and their ecosystem services. Transgenic Bt-crops have been genetically modified by inserting a Bacillus thuriengensis gene so the plant expresses a Cry toxin aimed for insect crop pests. Non-target soil invertebrates are particularly recognized for their contribution to plant nutrient availability and turnover of organic matter and it is therefore relevant to protect these invertebrate taxa. A number of studies have compared the population abundance and biomass of soil invertebrates in agricultural fields planted with genetically modified Bt crops and their conventional counterparts. Here, were review and analyze a selection of studies on Protista, nematodes, Collembola, mites, enchytraeids, and earthworms systematically to empower the evi- dence for asking the question whether population abundances and biomasses of soil invertebrates are changed by Bt crops compared to conventional crops. 6110 titles were captured, of which 38 studies passed our inclusion criteria, and a final number of 22 publications were subject to data extraction. A database with 2046 records was compiled covering 36 locations and the Bt types Cry1Ab, Cry1Ac, Cry3Bb1 and Cry3Aa. Comparative effect sizes in terms of Hedges’ g were calculated irrespectively of statistical significance of effects of the source studies. Cry effects on populations were compared across the studies in a meta-analysis employing a hierarchical Bayesian approach of weighted data according to the level of replication. The temporal development of effect sizes was modelled, thereby taking into account the variable duration of the field experiments. There was considerable variation among soil invertebrate orders, but the sample size was insufficient and the sample heterogeneity too large to draw any credible conclusions on the effect of Cry at the order level. However, across orders there was no significant effect of Cry on soil invertebrates.

Altres ajuts: COST Actions BIOLINK (FP1305) and KEYSOM (ES 1406). Jorge Curiel Yuste received funding by the Basque Government through the BERC 2018-2021 program. The relatively poor simulation of the below-ground processes is a severe drawback for many ecosystem models, especially when predicting responses to climate change and management. For a meaningful estimation of ecosystem production and the cycling of water, energy, nutrients and carbon, the integration of soil processes and the exchanges at the surface is crucial. It is increasingly recognized that soil biota play an important role in soil organic carbon and nutrient cycling, shaping soil structure and hydrological properties through their activity, and in water and nutrient uptake by plants through mycorrhizal processes. In this article, we review the main soil biological actors (microbiota, fauna and roots) and their effects on soil functioning. We review to what extent they have been included in soil models and propose which of them could be included in ecosystem models. We show that the model representation of the soil food web, the impact of soil ecosystem engineers on soil structure and the related effects on hydrology and soil organic matter (SOM) stabilization are key issues in improving ecosystem-scale soil representation in models. Finally, we describe a new core model concept (KEYLINK) that integrates insights from SOM models, structural models and food web models to simulate the living soil at an ecosystem scale.

BackgroundSoil fauna of the high arctic North Greenland above 79o latitude are particularly unknown, so we sampled the soil fauna within an area of 3 km x 5 km, 5 km south of the Villum Research Station, Station Nord, from August 3-6, 2016, in ten plots of 1,000 m2 (Fig. 1). Ten soil cores of diameter 7 cm and depth 5 cm were collected in each plot and the plant coverage were determined in 10 circles pr. plot. Soil cores were extracted in a MacFadyen high gradient extractor at Aarhus University, Dep. of Bioscience. The surface of most plots were characterized by less than 20% vegetation cover, while only two plots, characterized by either Papaver or Salix, had 50% and 40% vegetation cover, respectively. Collembola and enchytraeidsCollembola was the second largest microarthropod taxon. Enchytraeids, though not extracted by specific methods and therefore underestimated, had the biggest biomass of 37 mg m-2.Oribatid communityOribatid mites dominated the microarthropod fauna with 3,000 individuals m-2 (≈15 mg m-2 ) of the total microarthropods and enchytraeids of 4,100 m-2. The oribatid assembly, with species all known from the arctic, included: Iugoribates gracilis, Liochthonius muscorum, Tectocepheus tenuis and Camisia lapponica. I. gracilis made up 75% of the oribatids. I. gracilis and L. muscorum were found in sites with Arctic poppy, Papaver radicatum, grasses, lichens and mosses. C. lapponica was abundant in the Salix plot.Barcoding of the oribatid I. gracilisWe did COI barcoding of 27 adults and nymphs of I. gracilis in collaboration with NorBOL (Norwegian Barcode of Life) and obtained confirmation of their species identity through BOLD (Barcode of Life Database). Thus, the same species, as verified by the COI barcode, was found in the artic Canada at Ellesmere Island, Victoria Island and Bylot Island and they all belong to the BOLD BIN: BOLD:AAN6609. A synonym species was found in Manitoba and Victoria Island differing by 9% from the latter and assigned to BIN BOLD:AAH6608, and therefore would be a separate species named I. gracilis by mistake.Conclusions- There is a need to sample and barcode the circumpolar oribatids to reveal their species identity and ascertain previous identifications.- The soil fauna in the harsh environment of Princess Ingeborg Peninsula is scarce by its 4,000 indv. m-2 compared to e.g. Zackenberg where 175,000 indv. m-2 was reported (Sørensen et al. 2006).- Oribatids were affiliated with specific plant habitats.

Effects on soil Collembola of Cu, Zn, Pb, and Cd pollution from Cu smelters over 40 years were investigated in paddy fields from an area of Eastern China. We compared the field effects to those observed in single-species laboratory tests employing the hemiedaphic collembolan Folsomia candida and the epedaphic Sinella curviseta obtained from laboratory cultures and exposed to field-collected polluted soil. The results indicated that different collembolan species responded differently to the pollution in the fields and could be divided into sensitive, indifferent, and tolerant types accordingly. The abundance of sensitive species decreased as the pollution increased, but this was not the same for indifferent and tolerant species. The dominant species changed from sensitive to tolerant species as the pollution increased. The reproduction of F. candida and S. curviseta was most sensitive to the contaminated soil compared to growth and survival; the sensitivity of the two species was similar. The growth was more sensitive than the survival for F. candida but not for S. curviseta. The growth and survival of F. candida were much more sensitive than those of S. curviseta. Sensitivity of field populations of F. candida (EC10 31 [15–46]) and hemiedaphic species Folsomia quadrioculata (EC10 52 [0.7–102]) were comparable with sensitivity of the reproduction of F. candida in the single-species tests (EC10 21 [14–27]), suggesting that single-species test based on laboratory cultures and field soil could be used to link laboratory and field data and then reflect the field situation. S. curviseta could be used as an epedaphic species in single-species tests and F. quadrioculata as an indicator species for assessment of field effect.

Ecological Risk Assessment (ERA) of genetically modified crops for the soil environment is supported by guidelines already available for pesticides. They have very much in common and here we point out the salient features of empirical ERA methodology for soil invertebrates and the need to address ecosystem services through assessment of ecological processes contributed by soil invertebrate functional traits. The soil quality, bait lamina test, and earthworm burrowing activity are current candidates underpinning an ecosystem services assessment approach. Establishing functional trait databases, baseline data, and making links between them, will enable future assessment of soil ecosystem services.

The recording and evaluation of the diversity of soil organism communities has made considerable progress within the last decade (see, e.g., the results of the European FP7-project,,EcoFinders"). In particular, the large influence of these organisms on the ecological functions of the soil has been highlighted (e.g., maintenance of soil structure. organic matter decomposition). Equally important, it was shown that not only flagship species such as the deep-burrowing earthworm species Lumbricus terrestris, but also the highly diverse meso-and microfauna have to be considered. However, in Germany no regional coverage and comprehensive information regarding the biodiversity of soil invertebrates is available. Reasons for ignoring soil invertebrates are the lack of trained taxonomists, the only recent implementation of standard (i.e. ISO) sampling methods as well as the general lack of interest in these often small and inconspicuous species. In order to improve this situation, the German Federal Environmental Agency (UBA) started a project in 2018, aiming to develop a standardized, comprehensive and efficient program to monitor selected soil invertebrate groups all over Germany, representing different soils, land use forms (i.e. meadows, crop sites and forests) and regions. Currently, sampling started at 25 Permanent Soil Monitoring Sites (PSMS), looking in particular at earthworms (Lumbricidae), springtails (Collembola) and potworms (Enchytraeidae), and using ISO standard sampling methodology. Species belonging to these groups are determined by classic morphological methods but also by using modern genetical methods such as DNA-barcoding or cDNA and eDNA measurements. The final aim of the project is to develop an efficient, cost-effective, and routinely applicable soil invertebrate monitoring system, as a tool for the evaluation of soil invertebrate biodiversity under stress. First results of this project will be presented.

Earthworms are widely known to impact soil health, having a keyrole in nutrient cycling and are often referred to as soil engineers.They are vital for soil microbial assemblages particularly through theirfeeding and burrowing activity in soil. Earthworms feed on soil organicmatter and litter, and the resulting casts alter the soil microbialcommunity. However, the gut microbiome of earthworms remains less known.In this study, we used amplicon sequencing of the 16S rRNA gene forbacteria and 18S rRNA gene for eukaryotes to assess the gut communityassemblages of earthworm species within three genera Aporrectodea,Allolobophora and Lumbricus that represent different life forms sharingthe same habitat. The objective was to compare the gut microbiomeprofiles of eukaryotic and prokaryotic organisms to assess significanceof earthworm life forms, and to explore the cross kingdom networks in anattempt to identify keystone species. We found a high eukaryoticdiversity with a dominance of the SAR supergroup along with fungi andmetazoan in the earthworm gut. The bacterial community were dominated bymembers of Proteobacteria, Acidobacteria, Actinobacteria, Firmicutes, andVerrucomicrobia. The eukaryotic and prokaryotic communities showedsimilar differences in alpha diversity, being lowest in Lumbricusherculeus. The beta diversity showed earthworm species as a key factor inshaping gut microbiomes with L. herculeus harboring distinct microbiomescompared to species of Aporrectodea caliginosa, A. longa, A. tuberculataand Allolobophora chlorotica. Cross kingdom networks showed highinteractions between several protist and bacterial OTUs. In conclusion,this study suggested that the community assemblages of gut microbiomeswas shaped by earthworm species and life form, and such assemblageconsist of cross kingdom interactions among eukaryotes and prokaryotes.

The Circumpolar Biodiversity Monitoring Programme (CBMP) provides an opportunity to improve our knowledge of Arctic arthropod diversity, but initial baseline studies are required to summarise the status and trends of planned target groups of species known as Focal Ecosystem Components (FECs). We begin this process by collating available data for a relatively well-studied region in the Arctic, the North Atlantic region, summarising the diversity of key terrestrial arthropod FECs, and compiling trends for some representative species. We found the FEC classification system to be challenging to implement, but identified some key groups to target in the initial phases of the programme. Long-term data are scarce and exhibit high levels of spatial and temporal variability. Nevertheless, we found that a number of species and groups are in decline, mirroring patterns in other regions of the world. We emphasise that terrestrial arthropods require higher priority within future Arctic monitoring programmes. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13280-019-01162-5) contains supplementary material, which is available to authorized users.

Odour is one problem in the management of waste water from dairy, thus the organic Thise Dairy has developed an all year round solution releasing the waste water into underground tubes at 30 cm depth in a willow energy crop plantation established in 2013. The wastewater contains 0.3% dry matter, 150 mg L-1 N, 2 g salt L-1 of mainly sodium chloride, and a COD of 1100 mg -1 .Thousand m3 wastewater ha-1 was applied from Oct. 15 to Oct. 31, corresponding to 6.5 mm precipitation per day. Neighbour plots distant 20-30 m apart, one within the wastewater treated area and one just outside in the untreated control willow area, were established in Oct. 2017 and considered (non-randomized) blocks. In other words this was a Before-After-Control-Impact (BACI) design. Plots were sampled to estimate earthworm abundance one week before and one week after treatment (map link: goo.gl/tvvMuF). The willow was surrounded by an agricultural field with a history of wastewater fertilisation subject to an exploratory sampling.- We found seven species of earthworms in the willow and five in the agricultural soil. Juveniles of A. tuberculata, A. caliginosa, L. herculeus, L. castaneus, are morphologically intrageneric indistinguishable, so they were lumped together in their genus, e.g. Lumbricus sp. and Aporrectodea sp. - The pairwise positioned plots were very similar except for one pair.- A behavioural response after wastewater underground application was observed for L. herculeus with increased fresh biomass by 50% compared to the paired control plot (Fig. 3). In general no acute harmful effects was detected from wastewater application.- The willow earthworm community since its establishment in 2013 had developed into a composition more typical for undisturbed soil and managed forests as it is favored by the absence of tillage in the willow .

1. Investigating the functional facet of biodiversity provides ecologists with a deeper understanding of community assembly and ecosystem processes, from local to biogeographical scales. A central assumption in functional ecology is that interspecific trait variability is higher than intraspecific variability. The stable species hierarchy hypothesis states that for similar species found in different environmental conditions, their species trait ranking is conserved. In this study, we applied this trait hierarchy concept prevalent in plant ecology to the growing field of soil functional ecology, for which newly developed trait databases are being increasingly used. However, to date there have been few attempts to test for patterns of intraspecific trait variability in these databases. 2. We thus aimed to characterize how such patterns might influence (i) a species hierarchy based on trait values, and (ii) the conclusions of a trait-based analysis at a community level. To examine this, we used Collembola body size data (extracted from the BETSI database) as model trait. The source consisted of four regional trait datasets (Poland, Scandinavia, Spain and UK) and one dataset for which species traits are defined at a continental (European) scale. 3. We found that, firstly, species were consistently ranked in all the trait datasets, although slight differences were observed between continental and northern European (i.e. Scandinavia and UK) trait datasets. In the two northern datasets, body size was higher (ca. 10%), indicating an intraspecific body size gradient from temperate to colder northern regions that we assumed could be explained by latitudinal patterns. 4. Secondly, using selected published species abundance matrices (from experimental studies), we calculated the community-weighted mean body size using various trait datasets. The findings showed that the slight discrepancies observed between trait datasets can lead to different conclusions. 5. This work confirms that properly defining the extent of intraspecific trait variability in databases is of primary importance in order to ensure robust conclusions. This is particularly important for databases hosting large scale data, that might be influenced by biogeographical patterns as latitudinal gradients. We recommend using a local regional trait dataset when available or, if not, a continental trait dataset. As trait databases are now commonly used tools for performing trait-based analyses, it is crucial to carefully select the data used to make inferences.

The concept of soil health emphasizes the role of soil organisms in sustainable agriculture and relies on bioindicators to assess the impact of management options. This study employed Collembola, a key group of microarthropods with intimate links to soil microbial activity, as bioindicators to reveal the sustainability of using acidified cattle slurry. While environmental and plant production benefits of acidification are well known, effect of acidified slurry on Collembola is undocumented. We added Collembola to sandy soil mixed with untreated or acidified cattle slurry labelled with 15N and applied at two rates (corresponding to 30 and 90 Mg slurry ha−1). The collembolan community included two species for each vertical life-form: epedaphic (Sinella curviseta and Heteromurus nitidus), hemiedaphic (Proisotoma minuta and Hypogastrura assimilis) and euedaphic species (Folsomia fimetaria and Protaphorura fimata). Replicate mesocosmos were incubated for 28 or 56 days at 15 °C, 65% WHC and a 12 h light-dark cycle. The epedaphic species strongly declined at the end of the experiment, whereas P. minuta and F. fimetaria were positively affected by high rates of untreated and acidified slurry, respectively. The hemiedaphic P. minuta showed the highest abundances and accumulation of slurry-15N, especially when high rate of untreated slurry was applied. We conclude that the impact on Collembola of low rates of untreated and acidified slurry applied to agricultural soils is marginal while higher rates of slurry may subsequently form a favourable habitat for euedaphic species.

The impact of Bt proteins on non-target arthropods is less understood than their effects on target organisms where the mechanism of toxic action is known. Here, we report the effects of two Bt proteins, Cry1Ab and Cry1Ac, on gene expression in the non-target collembolan, Folsomia candida. A customized microarray was used to study gene expression in F. candida specimens that were exposed to Cry1Ab and Cry1Ac. All selected transcripts were subsequently confirmed by qPCR. Eleven transcripts were finally verified, and three of them were annotated. The responses of all eleven transcripts were tested in specimens for both Cry1Ab and Cry1Ac at a series of concentrations. These transcripts were separated into two and three groups for Cry1Ab and Cry1Ac, respectively, depend on their expression levels. However, those eleven transcripts did not respond to the Bt proteins in Bt-rice residues. © 2013 Elsevier Ltd. All rights reserved.

Thermal gasification of straw is a highly efficient technology that produces bioenergy and gasification biochar that can be used as a soil amendment, thereby returning non-renewable nutrients and stable carbon, and securing soil quality and crop productivity.A Danish on-farm field study investigated the impact of traditional straw incorporation vs. straw removal for thermal gasification bioenergy production and the application of straw gasification biochar (GB) on soil quality and crop production. Two rates of GB were applied over three successive years in which the field was cropped with winter wheat (Triticum aestivum L.), winter oilseed rape (Brassica napus L.) and winter wheat, respectively, to assess the potential effects on the soil carbon pool, soil microorganisms, earthworms, soil chemical properties and crop yields.The application of GB did not increase the soil organic carbon content significantly and had no effect on crop yields. The application of straw and GB had a positive effect on the populations of bacteria and protists, but no effect on earthworms. The high rate of GB increased soil exchangeable potassium content and soil pH indicating its potassium bioavailability and liming properties.These results suggest, that recycling GB into agricultural soils has the potential to be developed into a system combining bioenergy generation from agricultural residues and crop production, while maintaining soil quality. However, future studies should be undertaken to assess its long-term effects and to identify the optimum balance between straw removal and biochar application rate.

Introduction of legumes (i.e. white clover) in agricultural grasslands is a common practice toimprove yields, but how this affects soil fauna populations, particularly mesofauna, is still poorlyunderstood. We investigated taxonomical and functional differences of Collembola communitiesbetween plots with either perennial ryegrass (Lolium perenne L.), white clover (Trifolium repens L.)or a mixture of both in a Danish agricultural grassland. Soil was sampled six months and 14 monthsafter establishing the leys (September and May, respectively). Diet preferences were investigatedvia stable isotope analyses (SIA) of carbon (13C) and nitrogen (15 N). Collembolan abundance datawere used to analyse morphological and ecological traits of the collected taxa and calculatefunctional diversity indices. Our stable isotope results show that root-derived resources made largercontributions to epedaphic and hemiedaphic species in the white clover than ryegrass plots.Changes in taxa specific density and traits distribution as a response to the C:N ratio of plantmaterial, suggest that plant material quality was the main factor affecting the collembolancommunity, which was particularly evident comparing the two sampling occasions. Functionalrichness decreased under conditions of low quality material. Surprisingly, the mixture treatment didnot positively affect population densities, but rather hosted less hemi- and euedaphic species inSeptember, and less niche space, i.e functional richness, was occupied by the community underthese conditions. This suggests that habitat changes, via different plant composition, can affectsome functional groups, having in turn effects on the functional diversity of the community. Ourresults confirm previous findings that Collembola can change feeding habits according toenvironmental conditions. Introduction of legumes (i.e. white clover) in agricultural grasslands is a common practice to improve yields, but how this affects soil fauna populations, particularly mesofauna, is still poorly understood. We investigated taxonomical and functional differences of Collembola communities between plots with either perennial ryegrass (Lolium perenne L.), whiteclover (Trifolium repens L.) or a mixture of both in a Danish agricultural grassland 6 and 14 months after establishing the leys (September and May, respectively). Diet preferences were investigated via stable isotope analyses (SIA) of carbon (13C) and nitrogen (15N). Collembolan abundance data were used to analyse morphological and ecological traits of the collected taxa and calculate functional diversity indices. Our stable isotope results show that root-derived resources made larger contributions to epedaphic and hemiedaphic species in the white clover than ryegrass plots. Changes in taxa specific density and traits distribution as a response to the C:N ratio of plant material, suggest that plant material quality was the main factor affecting the collembolan community,especially when comparing the two sampling occasions. Functional richness decreased under conditions of low quality material. In contrast to our hypothesis, population densities did not increase under mixture treatment and functional richness decreased. Our results suggest that habitat changes, via different plant composition, can affect some functional groups, having in turn effects on the functional diversity of the community.

SUMMARYManaged grasslands are characterized by rotations of leys and arable crops. The regime of water flow evolves during the leys because of earthworm and root activity, climate and agricultural practices (fertilizer, cutting and cattle trampling). The effects of duration of the leys, cattle trampling and fertilizer practice on the movement of water through sandy loam soil profiles were investigated in managed grassland of a dairy operation. Experiments using tracer chemicals were performed, with or without cattle slurry application, with cutting or grazing, in the 1st and the 3rd year of ley, and in winter rye. Each plot was irrigated for an hour with 18·5 mm of water containing a conservative tracer, potassium bromide; 24 h after irrigation, macropores >1 mm were recorded visually on a horizontal plan of 0·7 m2 at five depths (10, 30, 40, 70 and 100 cm). The bromide (Br−) concentration in soil was also analysed at these depths and the density of the different earthworm species were recorded. The density of macropores was not directly influenced by the factors investigated. The abundance of anecic earthworms was larger after 3 years of ley and was not affected by grazing (trampling or dung pat deposits) or fertilizer practice. The water infiltration estimated from the Br− concentration was not influenced by fertilizer practice and was reduced after 3 years of ley due to settlement, but was greater than that for the arable phase of the rotation. As shown by Br− concentration, preferential flow was induced by the grazing regime. Infiltrating water may bypass the soil matrix under similar or more extreme conditions than in the current experiment. Such hydraulic functioning in the grazing regime is expected to reduce the risk of leaching of nitrate contained in soil water.

Despite their importance both in soil functioning and as soil indicators, the response of microarthropods to various land uses is still unclear. The aim of this study is to assess the effect of land use on microarthropod diversity and determine whether a soil's biological quality follows the same physicochemical quality-based gradient from forest, agriculture-grassland, agriculture-arable land, vineyards, urban vegetable gardens to urban, industrial, traffic, mining and military areas. A database compiling the characteristics of 758 communities has been established. We calculated Collembola community indices including: species richness, Pielou's evenness index, collembolan life forms, the abundance of Collembola and of Acari, the Acari/Collembola abundance ratio, and the Collembolan ecomorphological index. Results show that agricultural land use was the most harmful for soil microarthropod biodiversity, whilst urban and industrial land uses give the same level of soil biological quality as forests do. Furthermore, differences between the proportions of Acari and ecomorphological groups were observed between land uses. This study, defining soil microarthropod diversity baselines for current land uses, should therefore help in managing and preserving soil microarthropod biodiversity, especially by supporting the preservation of soil quality. (C) 2017 Elsevier B.V. All rights reserved.

Daggmaskarna skapar rör i jorden, underhåller och reparerar dem samt kopplar samman rören med förhistoriska rotkanaler långt ner i jordprofilen. Dräneringen kan därmed öka upp till 10 gånger med daggmaskar i jorden. Grödorna svarar på daggmaskarnas N-frigörande aktivitet med en skördeökning på i medeltal 25 procent.

11 páginas, 2 tablas, 6 figuras., 1 Physiological mechanisms such as allocation and release of nutrients are keys to understanding an animal's adaptation to a particular habitat. This study investigated how two detrivores with contrasting life-history traits allocated carbon (C) and nitrogen (N) to growth, reproduction and metabolism. As model organisms we used the collembolans, Proisotoma minuta (Tullberg 1871) and Protaphorura fimata (Gisin 1952). 2 To estimate allocations of C and N in tissue, we changed the isotopic composition of the animal's yeast diets when they became sexually mature and followed isotope turnover in tissue, growth and reproduction for 28 days. In addition, we measured the composition of C, N and phosphorus (P) to gain complementary information on the stoichiometry underlying life-history traits and nutrient allocation. 3 For P. minuta, the smallest and most fecund of the two species, the tissue turnover of C and N were 13% and 11% day−1, respectively. For P. fimata, the equivalent rates were 5% and 4% d−1, respectively. Protaphorura fimata had the lowest metabolic rate relative to total body mass but the highest metabolic rates relative to reproductive investment. Adult P. fimata retained approximately 17% of the nutrient reserves acquired while a juvenile and adult P. minuta about 11%. N and P contents of total tissue were significantly higher in P. minuta than in P. fimata, suggesting that tissue turnover was correlated with high protein-N and RNA-P. 4 Our results suggest that the lower metabolism and nutritional requirements by P. fimata than P. minuta is an adaptation to the generally low availability and quality of food in its natural habitat. 5 The methodological approach we implemented tracking mass balance, isotope turnover and elemental composition is promising for linking nutrient budgets and life-history traits in small invertebrates such as Collembola., This study was part of the research project ‘Closing the Rural-Urban Nutrient Cycle (CRUCIAL)’ supported by Danish Research Centre for Organic Farming, DARCOF. Thomas Larsen was supported by a Carbergfondet fellowhip and Marc Ventura was supported by a Marie Curie post-doctoral grant (MEIF-CT-2005-010554) and Juan de la Cierva and Ramon y Cajal grants (Spanish Ministry of Education and Science).