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Copyright of Arachnology Letters / Arachnologische Mitteilungen is the property of Arachnologische Gesellschaft e.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pesticides are extensively used in agriculture to prevent infestation of crops, control plant-associated diseases and pests, and increase crop productivity. With regards to typical agricultural practice, tank mixing of two or more plant protection products or the subsequent applications of herbicides, fungicides, and insecticides are common application strategies to improve pest control. Our study provides evidence that the fungicide mixture consisting of mancozeb, metalaxyl-M, and chlorothalonil, each applied according to their recommended field rates, retarded the degradation of the phenoxy herbicide 4-chloro-2-methylphenoxyacetic acid (MPCA) in soil. MCPA dissipation times were between 1.6 and 1.9 days without and 2.5–3.5 days with co-applied fungicides. Furthermore, the proportions of extractable residues, non-extractable residues, mineralization, volatile organic compounds, and MPCA metabolism were altered by the fungicide mixture, i.e., considerably lower amounts of the main transformation product of MCPA, 4-chloro-2-methylphenol, were formed. The effects induced by the fungicides persisted throughout the experiment. Our results demonstrate that the current situation of considering individual active substances in the authorization process for plant protection products could lead to a discrepancy in the exposure assessment for humans and the environment. For specifically these cases, this calls into question whether the legally required level of protection is provided. [ABSTRACT FROM AUTHOR]

Field studies to determine the effects of chemicals on earthworm communities are generally conducted according to International Organization for Standardization standard 11268‐3 (and later comments). However, statistical test procedures suggested in the guideline are frequently criticized, mainly for 2 reasons: 1) Earthworm abundances are count data and often do not fulfill requirements for multiple t tests (normal distribution and homogeneity of variance), and 2) the resulting toxicity metrics of multiple testing procedures (no/lowest‐observed‐effect concentrations [NOEC/LOEC]) fail to adequately detect the actual level of effects. Recently, a new method to overcome these shortcomings was presented by the introduction of the closure principle computational approach test (CPCAT). We applied this statistical method to assess chemical effects on abundance in a large dataset of 26 earthworm field studies (with up to 3 test chemical application rates) and an additional extended study with 6 application rates. A comparative analysis was provided considering results of well‐established multiple testing approaches (Dunnett's test) with particular consideration of the degree of overdispersion found in these data. It was shown that the CPCAT detects substantially more effects in earthworm field tests as statistically significant than standard t test approaches. This lowered the LOEC/NOEC for many chemical treatments to control comparisons. As a consequence, the statistically detected NOECs/LOECs were often set at lower percentage deviations between control and chemical treatment. This is the first time the performance of the CPCAT has been assessed within a comprehensive analysis of earthworm field study data. Environ Toxicol Chem 2021;40:1750–1760. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Green infrastructure in cities is considered to serve as a refuge for insect pollinators, especially in the light of an ongoing global decline of insects in agricultural landscapes. The design and maintenance of urban green spaces as key components of green infrastructure play a crucial role in case of nesting opportunities and for foraging insects. However, only few research has explored the impact of urban green space design on flower visitor communities, plant-pollinator interaction and the provision of the ecosystem service of pollination in cities. We investigated the abundance and diversity of pollinator communities in different urban park types in designed, standardized vegetation units, linked the visitation rates to the structural composition of the park types and derived indices for implemented pollination performances. The study was performed in two different structural park elements, flower beds and insect-pollinating trees. To gain a comprehensive understanding of the interaction between plants and pollinators, we calculated a plant-pollinator network of the recorded community in the investigation area. Visitation rates at different park types clearly showed, that the urban community gardens in comparison to other urban park types had a significantly higher abundance of pollinator groups, comparable to results found on a rural reference site. Tilia trees contributed significantly to the ecosystem service of pollination in investigated green spaces with a high supply of nectar and pollen during their flowering period. Calculations of pollination performances showed that recreational parks had comparably low visitation rates of pollinators and a high potential to improve conditions for the ecosystem service of pollination. The results indicated the strong potential of cities to provide a habitat for different groups of pollinators. In order to access this refuge, it is necessary to rely on near-natural concepts in design and maintenance, to create a wide range of flower diversity and to use even small green patches. Based on the findings, we encourage an integrated management of urban free spaces to consider parks as key habitats for pollinators in anthropogenic dominated, urban environments. [ABSTRACT FROM AUTHOR]

Highlights • Spruce forest conversion (SFC) by beech introduction increases fungal species richness. • SFC shifts fungal community composition and changes the functional structure. • Old-growth European beech forests act as a refugium for unique fungi. • Wind disturbance and further salvage logging decreases fungal species richness. Abstract This study investigated the response patterns of aboveground macrofungal communities to different management stages representing a forest conversion from Norway spruce (Picea abies) to European beech (Fagus sylvatica) in the Eifel National Park, Germany. We used a space-for-time substitution approach with three replicate study sites for each forest conversion stage: (I) even-aged single species Norway spruce, (II) unmanaged Norway spruce windthrow, (III) salvage-logged Norway spruce windthrow, (IV) single Norway spruce tree selection cutting (close-to-nature managed) with European beech underplanting and (V) old-growth, uneven-aged European beech (as reference). We assessed environmental variables and macrofungal sporocarps, while the latter were categorized into functional groups to link taxonomic information to potential ecosystem functions. Overall, we observed 235 macrofungal species. The highest species richness was found in the European beech reference stage, followed by the close-to-nature managed spruce/beech stage, while the Norway spruce stage showed approximately half the species richness, similar to the species level of both windthrow stages. Non-metric multidimensional scaling (NMDS) ordination separated each forest conversion stage into distinct fungal communities, while both windthrow stages could not be distinguished from each other. Beside tree species composition change and forest management, nutrient availability and microclimate were the main drivers of fungal community changes among the five differently-managed stages. Further, different functional groups responded in different patterns to forest management and to explanatory environmental variables. We reinforced the assumption, that old-growth, uneven-aged European beech forests (>120 years) can act as a refugium for unique forest type specific fungal communities with a higher functional structure, especially contrary to non-native, even-aged Norway spruce forests (∼70 years). Single Norway spruce tree selection cutting with further introduction of European beech trees can be an adequate strategy to allow a spruce forest conversion without necessarily reducing the macrofungal species richness and its functional structure. We displayed that ecological consequences of windthrow events can be a depression of fungal species richness and a collapse for the functional structure of fungi, especially after salvage logging. Our study underlines the need of including fungal conservation in forest conversion plans to optimize forest ecosystem integrity and resilience against biotic and abiotic agents, such as windstorm events. [ABSTRACT FROM AUTHOR]

In ecotoxicology, transcriptomics is an effective way to detect gene expression changes in response to environmental pollutants. Such changes can be used to identify contaminants or contaminant classes and can be applied as early warning signals for pollution. To do so, it is important to distinguish contaminant-specific transcriptomic changes from genetic alterations due to general stress. Here we present a first step in the identification of contaminant class-specific transcriptome signatures. Embryos of zebrafish (Danio rerio) were exposed to three substances (methylmercury, chlorpyrifos and Aroclor 1254, each from 24 to 48 hpf exposed) representing sediment typical contaminant classes. We analyzed the altered transcriptome to detect discriminative genes significantly regulated in reaction to the three applied contaminants. By comparison of the results of the three contaminants, we identified transcriptome signatures and biologically important pathways (using Cytoscape/ClueGO software) that react significantly to the contaminant classes. This approach increases the chance of finding genes that play an important role in contaminant class-specific pathways rather than more general processes. [ABSTRACT FROM AUTHOR]

The Edaphostat web application allows interactive and dynamic analyses of soil organism data stored in the Edaphobase data warehouse. It is part of the Edaphobase web application and can be accessed by any modern browser. The tool combines data from different sources (publications, field studies and museum collections) and allows species preferences along various environmental gradients (i.e. C/N ratio and pH) and classification systems (habitat type and soil type) to be analyzed. [ABSTRACT FROM AUTHOR]

Transcriptomics is often used to investigate changes in an organism's genetic response to environmental contamination. Data noise can mask the effects of contaminants making it difficult to detect responding genes. Because the number of genes which are found differentially expressed in transcriptome data is often very large, algorithms are needed to reduce the number down to a few robust discriminative genes. We present an algorithm for aggregated analysis of transcriptome data which uses multiple fold-change thresholds (threshold screening) and p values from Bayesian generalized linear model in order to assess the robustness of a gene as a potential indicator for the treatments tested. The algorithm provides a robustness indicator (ROBI) as well as a significance profile, which can be used to assess the statistical significance of a given gene for different fold-change thresholds. Using ROBI, eight discriminative genes were identified from an exemplary dataset ( Danio rerio FET treated with chlorpyrifos, methylmercury, and PCB) which could be potential indicators for a given substance. Significance profiles uncovered genetic effects and revealed appropriate fold-change thresholds for single genes or gene clusters. Fold-change threshold screening is a powerful tool for dimensionality reduction and feature selection in transcriptome data, as it effectively reduces the number of detected genes suitable for environmental monitoring. In addition, it is able to unmask patterns in altered genetic expression hidden by data noise and reduces the chance of type II errors, e.g., in environmental screening. [ABSTRACT FROM AUTHOR]

The article presents an environmental risk assessment (ERA) of the adverse ecological effects of chemical exposure and other anthropogenic stressors on freshwater organisms and their ecological recovery potential. Topics include types of stressors, the variations in recovery times of exposed animals based on taxonomic groups, and the impact of ecosystem type, landscape, and community processes. Other topics include recovery times based on stressor types and ecological recovery and legislation.

In this study we present evidence that anthropogenic stressors can reduce the resilience of age-structured populations. Enhancement of disturbance in a model-based Daphnia population lead to a repression of chaotic population dynamics at the same time increasing the degree of synchrony between the population's age classes. Based on the theory of chaos-mediated survival an increased risk of extinction was revealed for this population exposed to high concentrations of a chemical stressor. The Lyapunov coefficient was supposed to be a useful indicator to detect disturbance thresholds leading to alterations in population dynamics. One possible explanation could be a discrete change in attractor orientation due to external disturbance. The statistical analysis of Lyapunov coefficient distribution is proposed as a methodology to test for significant non-linear effects of general disturbance on populations. Although many new questions arose, this study forms a theoretical basis for a dynamical definition of population recovery. [ABSTRACT FROM AUTHOR]

A sediment contact test (SCT) battery consisting of five ecotoxicological test systems was applied to 21 native freshwater sediments characterized by a broad variety of geochemical properties and anthropogenic contamination. Higher plants ( Myriophyllum aquaticum), nematodes ( Caenorhabditis elegans), oligochaetes ( Lumbriculus variegatus), zebrafish embryos ( Danio rerio), and bacteria ( Arthrobacter globiformis), representing various trophic levels and exposure pathways, were used as test organisms. The test battery detected sediment toxicity caused by anthropogenic pollution, whereas the various tests provided site-specific, nonredundant information to the overall toxicity assessment. Based on the toxicity pattern derived from the test battery, the sediments were classified according to a newly proposed classification system for sediment toxicity assessment. The SCT-derived classification generally agreed well with the application of consensus-based sediment quality guidelines (SQGs), especially with regard to sediments with high toxic potential. For sediments with low to medium toxic potential, the SQGs often underestimated the toxicity that was detected by the SCTs, underpinning the need for toxicity tests in sediment quality assessment. Environ. Toxicol. Chem. 2013;32:144-155. © 2012 SETAC [ABSTRACT FROM AUTHOR]

1. As mature tropical forests disappear, secondary forests with their potential to conserve mature tropical forest species are increasingly of interest in a conservation context. 2. We investigated the recovery of litter inhabiting beetle diversity and composition during natural forest regeneration in the coastal submontane forest of Southern Brazil, using chronosequences on two different soil types: cambisol and gleysol. Secondary forests, ranging in ages from 5 to 50 years, as well as old-growth forests were studied. Beetles were sifted from leaf litter and extracted using the Winkler technique. 3. Young secondary forests had a very low species density and a significantly different and heterogeneous species composition compared to old-growth forests. During forest regeneration, species density greatly increased and the species composition of older secondary forests was similar to that of old-growth forests. The recovery pattern of species density and composition differed between soil types; nonetheless, they showed the same tendencies generally. Thus, mature secondary forests of about 35–50 years can be assumed to contribute substantially to the maintenance of forest beetle species. 4. Litter quantity was not only significantly correlated with species density; but, even reflected the density pattern of both soil types. Thus, litter quantity is an important factor for maintaining or recovering high beetle densities. The composition of beetle assemblages was strongly affected by soil type. Thus, soil type should be considered in regional biodiversity monitoring and conservation actions. [ABSTRACT FROM AUTHOR]

• Metabarcoding can identify community response patterns on spruce forest conversion. • Metabarcoding approach showed the genetic refugium of the soil fungal community. • Diverse beech-associated fungal communities can develop after spruce forest conversion. • Metabarcoding and morphological datasets should be interpreted by taxonomic experts. • Fungal eDNA metabarcoding cannot be used interchangeably for morphological analyses. Analyzing fungal diversity and community composition through environmental DNA (eDNA) metabarcoding and high-throughput sequencing relies on sequence databases and their taxonomic coverage which are often doubted in regards of data accuracy. To assess the potential of eDNA metabarcoding to distinguish differently managed forest conversion stages, we compared an extant morphological dataset created through sporocarp surveys with a metabarcoding dataset from the same study sites. The study was conducted along a spruce forest conversion project of Norway spruce towards European beech in the Eifel National Park in Germany. Using the UNITE ITS reference database, a total of 198 fungal operational taxonomic units (OTUs) were assigned up to the species level. Comparing the morphological and metabarcoding dataset, a low species overlap was observed with 27 shared fungi. The metabarcoding dataset revealed that all investigated forest conversion management stages shared beech-associated fungi (even the spruce forests), while within the morphological dataset, only the beech-inhabiting forest conversion management stages showed beech-associated fungi. The metabarcoding dataset could not show the same fungal community response patterns on the spruce forest conversion, compared to the morphological dataset, but revealed the genetic refugium of the soil fungal community. We conclude that fungal eDNA metabarcoding should always be evaluated by taxonomic experts to identify potential sequence database errors. eDNA metabarcoding cannot be used interchangeably for morphological community analyses to identify response patterns of fungal communities on forest management strategies. However, both approaches performed well in combination and showed that beech-associated fungal communities with high functional redundancy can develop after a spruce forest conversion by restoring natural European beech forests with an appropriate close-to-nature management strategy. [ABSTRACT FROM AUTHOR]

Lake ecosystems are sensitive recorders of environmental changes that provide continuous archives at annual to decadal resolution over thousands of years. The systematic investigation of land use changes and emission of pollutants archived in Holocene lake sediments as well as the reconstruction of contamination, background conditions, and sensitivity of lake systems offer an ideal opportunity to study environmental dynamics and consequences of anthropogenic impact that increasingly pose risks to human well-being. This paper discusses the use of sediment and other lines of evidence in providing a record of historical and current contamination in lake ecosystems. We present a novel approach to investigate impacts from human activities using chemical-analytical, bioanalytical, ecological, paleolimnological, paleoecotoxicological, archeological as well as modeling techniques. This multi-time slice weight-of-evidence (WOE) approach will generate knowledge on conditions prior to anthropogenic influence and provide knowledge to (i) create a better understanding of the effects of anthropogenic disturbances on biodiversity, (ii) assess water quality by using quantitative data on historical pollution and persistence of pollutants archived over thousands of years in sediments, and (iii) define environmental threshold values using modeling methods. This technique may be applied in order to gain insights into reference conditions of surface and ground waters in catchments with a long history of land use and human impact, which is still a major need that is currently not yet addressed within the context of the European Water Framework Directive. [ABSTRACT FROM AUTHOR]

Soils are faced with man-made chemical stress factors, such as the input of organic or metal-containing pesticides, in combination with non-chemical stressors like soil compaction and natural disturbance like drought. Although multiple stress factors are typically co-occurring in soil ecosystems, research in soil sciences on this aspect is limited and focuses mostly on single structural or functional endpoints. A mechanistic understanding of the reaction of soils to multiple stressors is currently lacking. Based on a review of resilience theory, we introduce a new concept for research on the ability of polluted soil (xenobiotics or other chemical pollutants as one stressor) to resist further natural or anthropogenic stress and to retain its functions and structure. There is strong indication that pollution as a primary stressor will change the system reaction of soil, i.e., its resilience, stability and resistance. It can be expected that pollution affects the physiological adaption of organisms and the functional redundancy of the soil to further stress. We hypothesize that the recovery of organisms and chemical-physical properties after impact of a follow-up stressor is faster in polluted soil than in non-polluted soil, i.e., polluted soil has a higher dynamical stability (dynamical stability = 1 / recovery time), whereas resilience of the contaminated soil is lower compared to that of not or less contaminated soil. Thus, a polluted soil might be more prone to change into another system regime after occurrence of further stress. We highlight this issue by compiling the literature exemplarily for the effects of Cu contamination and compaction on soil functions and structure. We propose to intensify research on effects of combined stresses involving a multidisciplinary team of experts and provide suggestions for corresponding experiments. Our concept offers thus a framework for system level analysis of soils paving the way to enhance ecological theory. [ABSTRACT FROM AUTHOR]