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There is widespread concern that cessation of grazing in historically grazed ecosystems is causing biotic homogenization and biodiversity loss. We used 12 montane grassland sites along an 800 km north-south gradient across the UK, to test whether cessation of grazing affects local α - and β -diversity of below-ground food webs. We show cessation of grazing leads to strongly decreased α -diversity of most groups of soil microbes and fauna, particularly of relatively rare taxa. By contrast, the β -diversity varied between groups of soil organisms. While most soil microbial communities exhibited increased homogenization after cessation of grazing, we observed decreased homogenization for soil fauna after cessation of grazing. Overall, our results indicate that exclusion of domesticated herbivores from historically grazed montane grasslands has far-ranging negative consequences for diversity of below-ground food webs. This underscores the importance of grazers for maintaining the diversity of below-ground communities, which play a central role in ecosystem functioning.

Present biodiversity comprises the evolutionary heritage of Earth's epochs. Lineages from particular epochs are often found in particular habitats, but whether current habitat decline threatens the heritage from particular epochs is unknown. We hypothesized that within a given region, humans threaten specifically habitats that harbor lineages from a particular geological epoch. We expect so because humans threaten environments that dominated and lineages that diversified during these epochs. We devised a new approach to quantify, per habitat type, diversification of lineages from different epochs. For Netherlands, one of the floristically and ecologically best-studied regions, we quantified the decline of habitat types and species in the past century. We defined habitat types based on vegetation classification and used existing ranking of decline of vegetation classes and species. Currently, most declining habitat types and the group of red-listed species are characterized by increased diversification of lineages dating back to Paleogene, specifically to Paleocene-Eocene and Oligocene. Among vulnerable habitat types with large representation of lineages from these epochs were sublittoral and eulittoral zones of temperate seas and 2 types of nutrient-poor, open habitats. These losses of evolutionary heritage would go unnoticed with classical measures of evolutionary diversity. Loss of heritage from Paleocene-Eocene became unrelated to decline once low competition, shade tolerance, and low proportion of non-Apiaceae were accounted for, suggesting that these variables explain the loss of heritage from Paleocene-Eocene. Losses of heritage from Oligocene were partly explained by decline of habitat types occupied by weak competitors and shade-tolerant species. Our results suggest a so-far unappreciated human threat to evolutionary heritage: habitat decline threatens descendants from particular epochs. If the trends persist into the future uncontrolled, there may be no habitats within the region for many descendants of evolutionary ancient epochs, such as Paleogene., (© 2020 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.)

Pyrethroid insecticides are known to be highly toxic to most aquatic nontarget organisms, but little is known about the mechanisms causing some species to be highly sensitive while others are hardly affected by the pyrethroids. The aim of the present study was to measure the sensitivity (EC 50 -values) of 10 aquatic invertebrates toward a 24 h pulse of the pyrethroid cypermethrin and subsequently test if the difference in sensitivity could be explained by measured morphological and physiological traits and modeled toxicokinetic (TK) and toxicodynamic (TD) parameters. Large differences were observed for the measured uptake and elimination kinetics, with bioconcentration factors (BCFs) ranging from 53 to 2337 at the end of the exposure. Similarly, large differences were observed for the TDs, and EC 50 -values after 168 h varied 120-fold. Modeling the whole organism cypermethrin concentrations indicated compartmentation into a sorbed fraction and two internal fractions: a bioavailable and non-bioavailable internal fraction. Strong correlations between surface/volume area and the TK parameters (sorption and uptake rate constants and the resulting BCF) were found, but none of the TK parameters correlated with sensitivity. The only parameter consistently correlating with sensitivity across all species was the killing rate constant of the GUTS-RED-SD model (the reduced general unified threshold models of survival assuming stochastic death), indicating that sensitivity toward cypermethrin is more related to the TD parameters than to TK parameters.

Aim: Alien plant species can cause severe ecological and economic problems, and therefore attract a lot of research interest in biogeography and related fields. To identify potential future invasive species, we need to better understand the mechanisms underlying the abundances of invasive tree species in their new ranges, and whether these mechanisms differ between their native and alien ranges. Here, we test two hypotheses: that greater relative abundance is promoted by (a) functional difference from locally co-occurring trees, and (b) higher values than locally co-occurring trees for traits linked to competitive ability., Location: Global., Time Period: Recent., Major Taxa Studied: Trees., Methods: We combined three global plant databases: sPlot vegetation-plot database, TRY plant trait database and Global Naturalized Alien Flora (GloNAF) database. We used a hierarchical Bayesian linear regression model to assess the factors associated with variation in local abundance, and how these relationships vary between native and alien ranges and depend on species' traits., Results: In both ranges, species reach highest abundance if they are functionally similar to co-occurring species, yet are taller and have higher seed mass and wood density than co-occurring species., Main Conclusions: Our results suggest that light limitation leads to strong environmental and biotic filtering, and that it is advantageous to be taller and have denser wood. The striking similarities in abundance between native and alien ranges imply that information from tree species' native ranges can be used to predict in which habitats introduced species may become dominant., (© 2019 The Authors. Global Ecology and Biogeography published by John Wiley & Sons Ltd.)

Increasing oil and gas activities may substantially increase chemical stress to benthic ecosystems in the Arctic, and it is necessary to evaluate such environmental risks in these systems. Risk assessment procedures for oil-related compounds (e.g., polycyclic aromatic hydrocarbons [PAHs]) should address differences in exposure between Arctic and temperate benthos. We compare for the first time the bioaccumulation of PAHs by Arctic benthic invertebrate species with that of temperate species, based on their biota-sediment accumulation factors (BSAFs). Measured PAH BSAFs were generally higher in temperate bivalves (Limecola balthica) than in Arctic bivalves (Macoma calcarea), whereas BSAFs in Arctic polychaetes (Nephtys ciliata) were higher than in temperate polychaetes (Alitta virens). Differences in measured BSAFs were explained by species-specific feeding modes and traits. However, modeled BSAFs revealed that steady state was not likely to be reached in the 28-d tests for all PAHs and organisms. Due to the low numbers of individuals, most species-specific parameters were too uncertain to reveal differences between Arctic and temperate species. The results of the present study suggest that data from temperate species could be used as a surrogate for Arctic species in risk assessment. Environ Toxicol Chem 2019;38:883-895. © 2019 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC., (© 2019 The Authors. Environmental Toxicology and Chemistry Published by Wiley Periodicals, Inc. on behalf of SETAC.)

This study assessed the long-term toxicity of chlorpyrifos on survival and reproduction of Banded Gourami by using mortality, gonado-somatic index (GSI) and histopathological observations as endpoints. Adult fish were exposed to five different concentrations of chlorpyrifos (0, 15, 50, 150, 500 µg/L) in 15 PVC tanks for 15, 30, 45, 60 and 75 days. Results showed that all male and female fish died after 15 days of 500 µg/L chlorpyrifos exposure. No consistent significant effect was observed for both male and female GSI. Furthermore, results showed dose- and time-dependent histopathological alterations for both ovary and testes. The 60-d No Observed Effect Concentration (NOEC) for most histopathological alterations of Banded Gourami ovary and testes was 50 μg/L, while 60-d NOEC for mortality of both male and female fish was < 15 μg/L. The results show that the long-term exposure to chlorpyrifos not only affect the reproductive tissues of Banded Gourami at exposure concentrations but also cause their mortality. Future studies should evaluate effects at lower concentrations.

Plant functional traits directly affect ecosystem functions. At the species level, trait combinations depend on trade-offs representing different ecological strategies, but at the community level trait combinations are expected to be decoupled from these trade-offs because different strategies can facilitate co-existence within communities. A key question is to what extent community-level trait composition is globally filtered and how well it is related to global versus local environmental drivers. Here, we perform a global, plot-level analysis of trait-environment relationships, using a database with more than 1.1 million vegetation plots and 26,632 plant species with trait information. Although we found a strong filtering of 17 functional traits, similar climate and soil conditions support communities differing greatly in mean trait values. The two main community trait axes that capture half of the global trait variation (plant stature and resource acquisitiveness) reflect the trade-offs at the species level but are weakly associated with climate and soil conditions at the global scale. Similarly, within-plot trait variation does not vary systematically with macro-environment. Our results indicate that, at fine spatial grain, macro-environmental drivers are much less important for functional trait composition than has been assumed from floristic analyses restricted to co-occurrence in large grid cells. Instead, trait combinations seem to be predominantly filtered by local-scale factors such as disturbance, fine-scale soil conditions, niche partitioning and biotic interactions.

Comparing plants of the same species thriving in flooded and non-flooded ecosystems helps to clarify the interplay between natural selection, phenotypic plasticity and stress adaptation. We focussed on responses of seeds and seedlings of Genipa americana and Guazuma ulmifolia to substrate waterlogging or total submergence. Both species are commonly found in floodplain forests of Central Amazonia and in seasonally dry savannas of Central Brazil (Cerrado). Although seeds of Amazonian and Cerrado G. americana were similar in size, the germination percentage of Cerrado seeds was decreased by submergence (3 cm water) and increased in Amazonian seeds. The seeds of Amazonian G. ulmifolia were heavier than Cerrado seeds, but germination of both types was unaffected by submergence. Three-month-old Amazonian and Cerrado seedlings of both species survived 30 days of waterlogging or submersion despite suffering significant inhibition in biomass especially if submerged. Shoot elongation was also arrested. Submersion triggered chlorosis and leaf abscission in Amazonian and Cerrado G. ulmifolia while waterlogging did so only in Cerrado seedlings. During 30 days of re-exposure to non-flooded conditions, G. ulmifolia plants that lost their leaves produced a replacement flush. However, they attained only half the plant dry mass of non-flooded plants. Both submerged and waterlogged G. americana retained their leaves. Consequently, plant dry mass after 30 days recovery was less depressed by these stresses than in G. ulmifolia . Small amounts of cortical aerenchyma were found in roots 2 cm from the tip of well-drained plants. The amount was increased by flooding. Waterlogging but not submergence promoted hypertrophy of lenticels at the stem base of both species and adventitious rooting in G. ulmifolia . Despite some loss of performance in dryland plants, flood tolerance traits were present in wetland and dryland populations of both species. They are part of an overall stress-response potential that permits flexible acclimation to locally flooded conditions.

The tundra is warming more rapidly than any other biome on Earth, and the potential ramifications are far-reaching because of global feedback effects between vegetation and climate. A better understanding of how environmental factors shape plant structure and function is crucial for predicting the consequences of environmental change for ecosystem functioning. Here we explore the biome-wide relationships between temperature, moisture and seven key plant functional traits both across space and over three decades of warming at 117 tundra locations. Spatial temperature-trait relationships were generally strong but soil moisture had a marked influence on the strength and direction of these relationships, highlighting the potentially important influence of changes in water availability on future trait shifts in tundra plant communities. Community height increased with warming across all sites over the past three decades, but other traits lagged far behind predicted rates of change. Our findings highlight the challenge of using space-for-time substitution to predict the functional consequences of future warming and suggest that functions that are tied closely to plant height will experience the most rapid change. They also reveal the strength with which environmental factors shape biotic communities at the coldest extremes of the planet and will help to improve projections of functional changes in tundra ecosystems with climate warming.

The United Nations' Sustainable Development Goals have been established to end poverty, protect the planet, and ensure prosperity for all. Delivery of the Sustainable Development Goals will require a healthy and productive environment. An understanding of the impacts of chemicals which can negatively impact environmental health is therefore essential to the delivery of the Sustainable Development Goals. However, current research on and regulation of chemicals in the environment tend to take a simplistic view and do not account for the complexity of the real world, which inhibits the way we manage chemicals. There is therefore an urgent need for a step change in the way we study and communicate the impacts and control of chemicals in the natural environment. To do this requires the major research questions to be identified so that resources are focused on questions that really matter. We present the findings of a horizon-scanning exercise to identify research priorities of the European environmental science community around chemicals in the environment. Using the key questions approach, we identified 22 questions of priority. These questions covered overarching questions about which chemicals we should be most concerned about and where, impacts of global megatrends, protection goals, and sustainability of chemicals; the development and parameterization of assessment and management frameworks; and mechanisms to maximize the impact of the research. The research questions identified provide a first-step in the path forward for the research, regulatory, and business communities to better assess and manage chemicals in the natural environment. Environ Toxicol Chem 2018;37:2281-2295. © 2018 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC., (© 2018 The Authors. Environmental Toxicology and Chemistry Published by Wiley Periodicals, Inc.)

The idea that noncrop habitat enhances pest control and represents a win-win opportunity to conserve biodiversity and bolster yields has emerged as an agroecological paradigm. However, while noncrop habitat in landscapes surrounding farms sometimes benefits pest predators, natural enemy responses remain heterogeneous across studies and effects on pests are inconclusive. The observed heterogeneity in species responses to noncrop habitat may be biological in origin or could result from variation in how habitat and biocontrol are measured. Here, we use a pest-control database encompassing 132 studies and 6,759 sites worldwide to model natural enemy and pest abundances, predation rates, and crop damage as a function of landscape composition. Our results showed that although landscape composition explained significant variation within studies, pest and enemy abundances, predation rates, crop damage, and yields each exhibited different responses across studies, sometimes increasing and sometimes decreasing in landscapes with more noncrop habitat but overall showing no consistent trend. Thus, models that used landscape-composition variables to predict pest-control dynamics demonstrated little potential to explain variation across studies, though prediction did improve when comparing studies with similar crop and landscape features. Overall, our work shows that surrounding noncrop habitat does not consistently improve pest management, meaning habitat conservation may bolster production in some systems and depress yields in others. Future efforts to develop tools that inform farmers when habitat conservation truly represents a win-win would benefit from increased understanding of how landscape effects are modulated by local farm management and the biology of pests and their enemies., Competing Interests: The authors declare no conflict of interest., (Copyright © 2018 the Author(s). Published by PNAS.)

The application of composted tannery sludge (CTS) has promoted shifts in soil chemical properties and, therefore, can affect the soil bacterial community. This study assessed the effect of the CTS on the soil bacterial community over time. The CTS was applied at five rates (0, 2.5, 5, 10 and 20 t/ha), and the bacterial community was evaluated for 180 days. The principal curve response (PRC) analysis showed that the most abundant phyla were not influenced by the CTS rates over time, while the analysis of the bacterial community showed that some of the less abundant phyla were influenced by the CTS rates. Similarly, the PRC analysis for the bacterial classes showed the significant effect of the CTS rates. The redundancy analyses for the bacterial phyla and classes showed the relationship between the significant chemical properties and the bacterial community of the soil after the CTS amendment over time. Therefore, there was a shift in the bacterial community over time with the application of the composted tannery sludge. Our study has shown that the less abundant bacterial groups were more influenced by the CTS than the most abundant bacterial groups and that these bacterial groups were driven by soil chemical properties, primarily chromium (Cr) and the soil pH.

Mediterranean-African countries (MACs) face a major water crisis. The annual renewable water resources are close to the 500 m 3 /capita threshold of absolute water scarcity, and water withdrawals exceed total renewable water resources by 30%. Such a low water availability curbs economic development in agriculture, which accounts for 86% of freshwater consumption. The analysis of the current situation of wastewater treatment, irrigation, and water management in MACs and of the research projects targeted to these countries indicates the need for 1) an enhanced capacity to analyze water stress, 2) the development of water management strategies capable of including wastewater reuse, and 3) development of locally adapted water treatment and irrigation technologies. This analysis shaped the MADFORWATER project (www.madforwater.eu), whose goal is to develop a set of integrated technological and management solutions to enhance wastewater treatment, wastewater reuse for irrigation, and water efficiency in agriculture in Egypt, Morocco, and Tunisia. MADFORWATER develops and adapts technologies for the production of irrigation-quality water from drainage canals and municipal, agro-industrial, and industrial wastewaters and technologies for water efficiency and reuse in agriculture, initially validated at laboratory scale, to 3 hydrological basins in the selected MACs. Selected technologies will be further adapted and validated in 4 demonstration plants of integrated wastewater treatment and reuse. Integrated strategies for wastewater treatment and reuse targeted to the selected basins are developed, and guidelines for the development of integrated water management strategies in other basins of the 3 target MACs will be produced. The social and technical suitability of the developed technologies and nontechnological tools in relation to the local context is evaluated with the participation of MAC stakeholders and partners. Guidelines on economic instruments and policies for the effective implementation of the proposed water management solutions in the target MACs will be developed. Integr Environ Assess Manag 2018;14:447-462. © 2018 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC)., (© 2018 The Authors. Integrated Environmental Assessment and Management Published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).)

Trees scale leaf (A L ) and xylem (A X ) areas to couple leaf transpiration and carbon gain with xylem water transport. Some species are known to acclimate in A L  : A X balance in response to climate conditions, but whether trees of different species acclimate in A L  : A X in similar ways over their entire (continental) distributions is unknown. We analyzed the species and climate effects on the scaling of A L vs A X in branches of conifers (Pinus sylvestris, Picea abies) and broadleaved (Betula pendula, Populus tremula) sampled across a continental wide transect in Europe. Along the branch axis, A L and A X change in equal proportion (isometric scaling: b ˜ 1) as for trees. Branches of similar length converged in the scaling of A L vs A X with an exponent of b = 0.58 across European climates irrespective of species. Branches of slow-growing trees from Northern and Southern regions preferentially allocated into new leaf rather than xylem area, with older xylem rings contributing to maintaining total xylem conductivity. In conclusion, trees in contrasting climates adjust their functional balance between water transport and leaf transpiration by maintaining biomass allocation to leaves, and adjusting their growth rate and xylem production to maintain xylem conductance., (© 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.)

Many studies have reported that hydraulic properties vary considerably between tree species, but little is known about their intraspecific variation and, therefore, their capacity to adapt to a warmer and drier climate. Here, we quantify phenotypic divergence and clinal variation for embolism resistance, hydraulic conductivity and branch growth, in four tree species, two angiosperms (Betula pendula, Populus tremula) and two conifers (Picea abies, Pinus sylvestris), across their latitudinal distribution in Europe. Growth and hydraulic efficiency varied widely within species and between populations. The variability of embolism resistance was in general weaker than that of growth and hydraulic efficiency, and very low for all species but Populus tremula. In addition, no and weak support for a safety vs. efficiency trade-off was observed for the angiosperm and conifer species, respectively. The limited variability of embolism resistance observed here for all species except Populus tremula, suggests that forest populations will unlikely be able to adapt hydraulically to drier conditions through the evolution of embolism resistance.

The neonicotinoid insecticide imidacloprid is used in Bangladesh for a variety of crop protection purposes. Imidacloprid may contaminate aquatic ecosystems via spray drift, surface runoff and ground water leaching. The present study aimed at assessing the fate and effects of imidacloprid on structural (phytoplankton, zooplankton, macroinvertebrates and periphyton) and functional (organic matter decomposition) endpoints of freshwater, sub-tropical ecosystems in Bangladesh. Imidacloprid was applied weekly to 16 freshwater microcosms (PVC tanks containing 400 L de-chlorinated tap water) at nominal concentrations of 0, 30, 300, 3000 ng/L over a period of 4 weeks. Results indicated that imidacloprid concentrations from the microcosm water column declined rapidly. Univariate and multivariate analysis showed significant effects of imidacloprid on the zooplankton and macroinvertebrate community, some individual phytoplankton taxa, and water quality variables (i.e. DO, alkalinity, ammonia and nitrate), with Cloeon sp., Diaptomus sp. and Keratella sp. being the most affected species, i.e. showing lower abundance values in all treatments compared to the control. The observed high sensitivity of Cloeon sp. and Diaptomus sp. was confirmed by the results of single species tests. No significant effects were observed on the species composition of the phytoplankton, periphyton biomass and organic matter decomposition for any of the sampling days. Our study indicates that (sub-)tropical aquatic ecosystems can be much more sensitive to imidacloprid compared to temperate ones., (Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.)

This paper deals with species sensitivity distributions (SSDs) for the lipophilic insecticide lufenuron and benthic arthropods based on sediment-spiked laboratory toxicity tests. This compound that inhibits chitin synthesis and moulting of arthropods persists in sediment. Using field-collected sediment, toxicity tests were conducted with three macro-crustaceans and six insects. The Hazardous Concentration to 5% of the tested species, the HC5 (and 95% confidence limit), derived from an SSD constructed with 10d-LC50's was 2.2 (1.2-5.7) μg/g organic carbon (OC) in dry sediment. In addition, HC5 values derived from SSDs constructed with 28d-LC10 and 28-d LC50 values were 0.13 (0.02-1.50) μg/g OC and 2.0 (1.3-5.5) μg/g OC, respectively. In 28d toxicity tests with Chironomus riparius and Hyalella azteca, a higher sensitivity was observed when using lufenuron-spiked field-collected sediment than in lufenuron-spiked artificial sediment. Overall, the non-biting midge C. riparius appeared to be a representative and sensitive standard test species to assess effects of lufenuron exposure in sediment. The Tier-1 (based on standard test species), Tier-2 (based on standard and additional test species) and Tier-3 (model ecosystem approach) regulatory acceptable concentrations (RACs) for sediment-spiked lufenuron did not differ substantially. The Tier-2 RAC was the lowest. Since to our knowledge this study is the first in the open literature that evaluates the tiered approach in the sediment effect assessment procedure for pesticides, we advocate that similar evaluations should be conducted for pesticides that differ in toxic mode-of-action., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The ecosystem services (ES) approach is gaining broad interest in regulatory and policy arenas for use in landscape management and ecological risk assessment. It has the potential to bring greater ecological relevance to the setting of environmental protection goals and to the assessment of the ecological risk posed by chemicals. A workshop, organised under the auspices of the Society of Environmental Toxicology and Chemistry Europe, brought together scientific experts from European regulatory authorities, the chemical industry and academia to discuss and evaluate the challenges associated with implementing an ES approach to chemical ecological risk assessment (ERA). Clear advantages of using an ES approach in prospective and retrospective ERA were identified, including: making ERA spatially explicit and of relevance to management decisions (i.e. indicating what ES to protect and where); improving transparency in communicating risks and trade-offs; integrating across multiple stressors, scales, habitats and policies. A number of challenges were also identified including: the potential for increased complexity in assessments; greater data requirements; limitations in linking endpoints derived from current ecotoxicity tests to impacts on ES. In principle, the approach was applicable to all chemical sectors, but the scale of the challenge of applying an ES approach to general chemicals with widespread and dispersive uses leading to broad environmental exposure, was highlighted. There was agreement that ES-based risk assessment should be based on the magnitude of impact rather than on toxicity thresholds. The need for more bioassays/tests with functional endpoints was recognized, as was the role of modelling and the need for ecological production functions to link measurement endpoints to assessment endpoints. Finally, the value of developing environmental scenarios that can be combined with spatial information on exposure, ES delivery and service provider vulnerability was recognized., (Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.)

The contemporary state of functional traits and species richness in plant communities depends on legacy effects of past disturbances. Whether temporal responses of community properties to current environmental changes are altered by such legacies is, however, unknown. We expect global environmental changes to interact with land-use legacies given different community trajectories initiated by prior management, and subsequent responses to altered resources and conditions. We tested this expectation for species richness and functional traits using 1814 survey-resurvey plot pairs of understorey communities from 40 European temperate forest datasets, syntheses of management transitions since the year 1800, and a trait database. We also examined how plant community indicators of resources and conditions changed in response to management legacies and environmental change. Community trajectories were clearly influenced by interactions between management legacies from over 200 years ago and environmental change. Importantly, higher rates of nitrogen deposition led to increased species richness and plant height in forests managed less intensively in 1800 (i.e., high forests), and to decreases in forests with a more intensive historical management in 1800 (i.e., coppiced forests). There was evidence that these declines in community variables in formerly coppiced forests were ameliorated by increased rates of temperature change between surveys. Responses were generally apparent regardless of sites' contemporary management classifications, although sometimes the management transition itself, rather than historic or contemporary management types, better explained understorey responses. Main effects of environmental change were rare, although higher rates of precipitation change increased plant height, accompanied by increases in fertility indicator values. Analysis of indicator values suggested the importance of directly characterising resources and conditions to better understand legacy and environmental change effects. Accounting for legacies of past disturbance can reconcile contradictory literature results and appears crucial to anticipating future responses to global environmental change., (© 2017 John Wiley & Sons Ltd.)

Previous studies of Eurasian grasslands have suggested that nutrient ratios, rather than absolute nutrient availabilities and associated productivity, may be driving plant species richness patterns. However, the underlying assumption that species occupy distinct niches along nutrient ratio gradients remains to be tested. We analysed plant community composition and nutrient status of 644 Eurasian wet grassland plots. The importance of nutrient ratios driving variation in species composition was analysed using ordination methods (DCA and CCA). Subsequently, we assessed the niche position and width along the most important nutrient ratio gradient [N:P] for each species. We found that the N:P ratio explained part of the variation in species composition independent from conventional explanatory variables. The N:P ratio explained less variation than soil moisture or pH, but more than productivity or the availability of N and P separately, highlighting its importance for grassland species composition. Species occupied distinct niches along the N:P gradient, and species' niche widths decreased toward extreme nutrient limitation. After correcting for niche position, there was no overall difference in niche width between endangered and non-endangered species. Surprisingly, endangered species with niche optima at the extreme P-limited end of the gradient had broader niches than their non-endangered counterparts. As species occupied distinct niches along a nutrient ratio gradient, future grassland conservation efforts may benefit from targeting changes in nutrient ratios, i.e. the balance between N and P, rather than only focussing on a general reduction in nutrient availability. However, what management interventions can be used for this purpose remains unclear.

In literature, varying and sometimes conflicting effects of physicochemical properties of nanoparticles (NPs) are reported on their uptake and effects in organisms. To address this, small- and medium-sized (20 and 50 nm) silver nanoparticles (AgNPs) with specified different surface coating/charges were synthesized and used to systematically assess effects of NP-properties on their uptake and effects in vitro. Silver nanoparticles were fully characterized for charge and size distribution in both water and test media. Macrophage cells (RAW 264.7) were exposed to these AgNPs at different concentrations (0-200 µg/ml). Uptake dynamics, cell viability, induction of tumor necrosis factor (TNF)-α, ATP production, and reactive oxygen species (ROS) generation were assessed. Microscopic imaging of living exposed cells showed rapid uptake and subcellular cytoplasmic accumulation of AgNPs. Exposure to the tested AgNPs resulted in reduced overall viability. Influence of both size and surface coating (charge) was demonstrated, with the 20-nm-sized AgNPs and bovine serum albumin (BSA)-coated (negatively charged) AgNPs being slightly more toxic. On specific mechanisms of toxicity (TNF-α and ROS production) however, the AgNPs differed to a larger extent. The highest induction of TNF-α was found in cells exposed to the negatively charged AgNP&#95;BSA, both sizes (80× higher than control). Reactive oxygen species induction was only significant with the 20 nm positively charged AgNP&#95;Chit.

West Nile virus (WNV) and Usutu virus (USUV) are arboviruses that are maintained in enzootic transmission cycles between mosquitoes and birds and are occasionally transmitted to mammals. As arboviruses are currently expanding their geographic range and emerging in often unpredictable locations, surveillance is considered an important element of preparedness. To determine whether sera collected from resident and migratory birds in the Netherlands as part of avian influenza surveillance would also represent an effective source for proactive arbovirus surveillance, a random selection of such sera was screened for WNV antibodies using a commercial ELISA. In addition, sera of jackdaws and carrion crows captured for previous experimental infection studies were added to the selection. Of the 265 screened serum samples, 27 were found to be WNV-antibody-positive, and subsequent cross-neutralization experiments using WNV and USUV confirmed that five serum samples were positive for only WNV-neutralizing antibodies and seven for only USUV. The positive birds consisted of four Eurasian coots (Fulica atra) and one carrion crow (Corvus corone) for WNV, of which the latter may suggest local presence of the virus, and only Eurasian coots for USUV. As a result, the screening of a small selection of serum samples originally collected for avian influenza surveillance demonstrated a seroprevalence of 1.6% for WNV and 2.8% for USUV, suggesting that this sustained infrastructure could serve as a useful source for future surveillance of arboviruses such as WNV and USUV in the Netherlands., (© 2017 Blackwell Verlag GmbH.)

Primary producers are amongst the most sensitive organisms to antibiotic pollution in aquatic ecosystems. To date, there is little information on how different environmental conditions may affect their sensitivity to antibiotics. In this study we assessed how temperature, genetic variation and species competition may affect the sensitivity of the cyanobacterium Microcystis aeruginosa and the green-algae Scenedesmus obliquus to the antibiotic enrofloxacin. First, we performed single-species tests to assess the toxicity of enrofloxacin under different temperature conditions (20°C and 30°C) and to assess the sensitivity of different species strains using a standard temperature (20°C). Next, we investigated how enrofloxacin contamination may affect the competition between M. aeruginosa and S. obliquus. A competition experiment was performed following a full factorial design with different competition treatments, defined as density ratios (i.e. initial bio-volume of 25/75%, 10/90% and 1/99% of S. obliquus/M. aeruginosa, respectively), one 100% S. obliquus treatment and one 100% M. aeruginosa treatment, and four different enrofloxacin concentrations (i.e. control, 0.01, 0.05 and 0.10mg/L). Growth inhibition based on cell number, bio-volume, chlorophyll-a concentration as well as photosynthetic activity were used as evaluation endpoints in the single-species tests, while growth inhibition based on measured chlorophyll-a was primarily used in the competition experiment. M. aeruginosa photosynthetic activity was found to be the most sensitive endpoint to enrofloxacin (EC50-72h =0.02mg/L), followed by growth inhibition based on cell number. S. obliquus was found to be slightly more sensitive at 20°C than at 30°C (EC50-72h cell number growth inhibition of 38 and 41mg/L, respectively), whereas an opposite trend was observed for M. aeruginosa (0.047 and 0.037mg/L, respectively). Differences in EC50-72h values between algal strains of the same species were within a factor of two. The competition experiment showed that M. aeruginosa growth can be significantly reduced in the presence of S. obliquus at a density ratio of 75/25% M. aeruginosa/S. obliquus, showing a higher susceptibility to enrofloxacin than in the single-species test. The results of this study confirm the high sensitivity of cyanobacteria to antibiotics and show that temperature and inter-strain genetic variation may have a limited influence on their response to them. The results of the competition experiment suggest that the structure of primary producer communities can be affected, at least temporarily, at antibiotic concentrations close to those that have been measured in the environment., (Copyright © 2017 Elsevier Inc. All rights reserved.)

In the aquatic tier-1 effect assessment for plant protection products with an herbicidal mode of action in Europe, it is usually algae and/or vascular plants that determine the environmental risks. This tier includes tests with at least 2 algae and 1 macrophyte (Lemna). Although such tests are considered to be of a chronic nature (based on the duration of the test in relation to the life cycle of the organism), the measurement endpoints derived from the laboratory tests with plants (including algae) and used in the first-tier effect assessment for herbicides are acute effect concentrations affecting 50% of the test organisms (EC50 values) and not no-observed-effect concentrations (NOECs) or effect concentrations affecting 10% of the test organisms (EC10) values. Other European legislative frameworks (e.g., the Water Framework Directive) use EC10 values. The present study contributes to a validation of the tiered herbicide risk assessment approach by comparing the standard first-tier effect assessment with results of microcosm and mesocosm studies. We evaluated EC50 and EC10 values for standard test algae and macrophytes based on either the growth rate endpoint (E r C50) or the lowest available endpoint for growth rate or biomass/yield (E r /E y C50). These values were compared with the regulatory acceptable concentrations for the threshold option as derived from microcosm and mesocosm studies. For these studies, protection is maintained if growth rate is taken as the regulatory endpoint instead of the lowest value of either growth rate or biomass/yield in conjunction with the standard assessment factor of 10. Based on a limited data set of 14 herbicides, we did not identify a need to change the current practice. Environ Toxicol Chem 2018;37:175-183. © 2017 SETAC., (© 2017 SETAC.)

Information from effects of pesticides in sediments at an ecosystem level, to validate current and proposed risk assessment procedures, is scarce. A sediment-spiked outdoor freshwater microcosm experiment was conducted with fludioxonil (lipophilic, non-systemic fungicide) to study exposure dynamics and treatment-related responses of benthic and pelagic macroinvertebrates and zooplankton. Besides blank control and solvent control systems the experiment had six different treatment levels (1.7-614mga.s./kg dry sediment) based around the reported 28-d No Observed Effect Concentration (NOEC) for Chironomus riparius (40mga.s./kg dry sediment). Twelve systems were available per treatment of which four were sacrificed on each of days 28, 56 and 84 after microcosm construction. Fludioxonil persisted in the sediment and mean measured concentrations were 53-82% of the initial concentration after 84days. The dissipation rate increased with the treatment level. Also exposure concentrations in overlying water were long-term, with highest concentrations 28days after initiation of the experiment. Sediment-dwelling Oligochaeta and pelagic Rotifera and Cladocera showed the most pronounced treatment-related declines. The most sensitive sediment-dwelling oligochaete was Dero digitata (population NOEC 14.2mga.s./kg dry sediment). The same NOEC was calculated for the sediment-dwelling macroinvertebrate community. The most sensitive zooplankton species was the cladoceran Diaphanosoma brachyurum (NOEC of 1.6μga.s./L in overlying water corresponding to 5.0mga.s./kg dry sediment). At the two highest treatments several rotifer taxa showed a pronounced decrease, while the zooplankton community-level NOEC was 5.6μga.s./L (corresponding to 14.2mga.s./kg dry sediment). Zooplankton taxa calanoid Copepoda and Daphnia gr. longispina showed a pronounced treatment-related increase (indirect effects). Consequently, an assessment factor of 10 to the chronic laboratory NOECs of Chironomus riparius (sediment) and Daphnia magna (water) results in a regulatory acceptable concentration that is sufficiently protective for both the sediment-dwelling and pelagic organisms in the microcosms., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Aim: Agricultural intensification and urbanization are important drivers of biodiversity change in Europe. Different aspects of bee community diversity vary in their sensitivity to these pressures, as well as independently influencing ecosystem service provision (pollination). To obtain a more comprehensive understanding of human impacts on bee diversity across Europe, we assess multiple, complementary indices of diversity., Location: One Thousand four hundred and forty six sites across Europe., Methods: We collated data on bee occurrence and abundance from the published literature and supplemented them with the PREDICTS database. Using Rao's Quadratic Entropy, we assessed how species, functional and phylogenetic diversity of 1,446 bee communities respond to land-use characteristics including land-use class, cropland intensity, human population density and distance to roads. We combined these models with statistically downscaled estimates of land use in 2005 to estimate and map-at a scale of approximately 1 km 2 -the losses in diversity relative to semi-natural/natural baseline (the predicted diversity of an uninhabited grid square, consisting only of semi-natural/natural vegetation)., Results: We show that-relative to the predicted local diversity in uninhabited semi-natural/natural habitat-half of all EU27 countries have lost over 10% of their average local species diversity and two-thirds of countries have lost over 5% of their average local functional and phylogenetic diversity. All diversity measures were generally lower in pasture and higher-intensity cropland than in semi-natural/natural vegetation, but facets of diversity showed less consistent responses to human population density. These differences have led to marked spatial mismatches in losses: losses in phylogenetic diversity were in some areas almost 20 percentage points (pp.) more severe than losses in species diversity, but in other areas losses were almost 40 pp. less severe., Main Conclusions: These results highlight the importance of exploring multiple measures of diversity when prioritizing and evaluating conservation actions, as species-diverse assemblages may be phylogenetically and functionally impoverished, potentially threatening pollination service provision.

Composting has been suggested as an efficient method for tannery sludge recycling before its application to the soil. However, the application of composted tannery sludge (CTS) should be monitored to evaluate its effect on the chemical and microbial properties of soil. This study evaluated the time-dependent effect of CTS on the chemical and microbial properties of soil. CTS was applied at 0, 2.5, 5, 10, and 20 Mg ha -1 and the soil chemical and microbial properties were evaluated at 0, 45, 75, 150, and 180 days. Increased CTS rates increased the levels of Ca, Cr, and Mg. While Soil pH, organic C, and P increased with the CTS rates initially, this effect decreased over time. Soil microbial biomass, respiration, metabolic quotient, and dehydrogenase increased with the application of CTS, but decreased over time. Analysis of the Principal Response Curve showed a significant effect of CTS rate on the chemical and microbial properties of the soil over time. The weight of each variable indicated that all soil properties, except β-glucosidase, dehydrogenase and microbial quotient, increased due to the CTS application. However, the highest weights were found for Cr, pH, Ca, P, phosphatase and total organic C. The application of CTS in the soil changed the chemical and microbial properties over time, indicating Cr, pH, Ca, phosphatase, and soil respiration as the more responsive chemical and microbial variables by CTS application.

In protected areas managers have to achieve conservation targets while providing opportunities for outdoor recreation. This dual mandate causes conflicts in choosing between management options. Furthermore, the persistence of a protected species within the management unit often depends on how conservation areas elsewhere in the region are managed. We present an assessment procedure to guide groups of managers in aligning outdoor recreation and bird conservation targets for a regional scale protected area in the Netherlands. We used existing bird monitoring data and simulated visitor densities to statistically model the impact of outdoor recreation on bird densities. The models were used to extrapolate the local impacts for other parts of the area, but also to assess the impact on conservation targets at the regional level that were determined by the national government. The assessment shows impacts of outdoor recreation on Nightjar (Caprimulgus europaeus), Stonechat (Saxicola torquata) and Woodlark (Lullula arborea), reducing the regional population by up to 28 percent. The Woodlark population size was reduced below the level of the politically determined conservation target. The output of the regression models provides information that connects implications of local management to regional scale conservation targets. The spatial maps of bird densities can help in deciding where reducing visitor disturbance is expected to result in increasing bird populations, or where alternative measures, such as improving the habitat conditions, could be effective. We suggest that by using our assessment procedure collaborative decision making is facilitated., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Urban rivers may receive contamination from various sources including point sources like domestic sewage and nonpoint sources (e.g., runoff), resulting in contamination with various chemicals. This study investigated the occurrence of emerging organic contaminants (3 endocrine disrupting compounds (EDCs), and 17 pharmaceuticals and personal care products (PPCPs)) in six urban rivers of a representative subtropical city, Guangzhou (southern China). Our results showed that EDCs and personal care products were frequently detected in the water phase and sediment phase. 4-nonylphenol (4-NP) was the most predominant compound with the highest concentration of 5050ng/L in the water phase and 14,400ng/g dry weight (dw) in the sediment. Generally, higher total concentrations of EDCs and PPCPs were detected in the four urban streams compared to the main stream Zhujiang River and the Liuxi River at the suburb area. A screening-level risk assessment showed that 4-nonylphenol and triclosan (TCS) pose potential risks to aquatic organisms in most sampling sites. For individual taxa, 4-NP may pose risks to various groups of aquatic organisms, while TCS only might pose high risks to algae., Capsule: Higher contamination of EDCs and PPCPs was observed in rivers in urban area; 4-nonylphenol and triclosan showed RQs>1 in >70% of the reported area., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The principal response curve (PRC) method is a constrained ordination method developed specifically for the analysis of community data collected in mesocosm experiments, which provides easily understood summaries and graphical representations of community response to stress. It is a redundancy analysis method and is usually performed on log-transformed abundance data. The choice of a measure of dissimilarity between samples and the choice of the data transformation significantly affect the results of multivariate analysis. Dissimilarity measures that are more ecologically meaningful than the Euclidean distance can be incorporated into the PRC using distance-based redundancy analysis. The present study investigates the ordinations produced by a small selection of dissimilarity measures: the Euclidean distance using log-transformed and Hellinger-transformed data and the Bray-Curtis dissimilarity using raw and log-transformed data. It compares 2 data sets from experiments on the effect of the anti-inflammatory drug diclofenac and the insecticide chlorpyrifos on macroinvertebrate communities. The choice of dissimilarity measure can determine the outcome of a risk assessment. For the diclofenac data set, the PRCs were different depending on the dissimilarity measure: the community no-effect concentration was lowest for the Bray-Curtis on log-transformed data and Hellinger dissimilarity measures. For chlorpyrifos, however, the PRCs were similar for all dissimilarity measures. Environ Toxicol Chem 2017;36:1667-1679. © 2016 SETAC., (© 2016 SETAC.)

Many goose species feed on agricultural land, and with growing goose numbers, conflicts with agriculture are increasing. One possible solution is to designate refuge areas where farmers are paid to leave geese undisturbed. Here, we present a generic modelling tool that can be used to designate the best locations for refuges and to gauge the area needed to accommodate the geese. With a species distribution model, locations are ranked according to goose suitability. The size of the area to be designated as refuge can be chosen by including more or less suitable locations. A resource depletion model is then used to estimate whether enough resources are available within the designated refuge to accommodate all geese, taking into account the dynamics of food resources, including depletion by geese. We illustrate this with the management scheme for pink-footed goose Anser brachyrhynchus implemented in Norway. Here, all geese can be accommodated, but damage levels appear to depend on weather, land use and refuge size.

In exposure prediction for environmental risk assessment, the transition to more dynamic and realistic modelling approaches and scenarios has been recently identified as a major challenge, since it would allow a more accurate prediction of bioavailable concentrations and their variations in space and time. In this work, an improved version of the multimedia model ChimERA fate, including a phytoplankton compartment and equations to calculate phytoplankton, detritus and dissolved organic matter variations in time, was developed. The model was parameterized to simulate five dynamic scenarios for shallow meso-eutrophic water bodies based on a latitudinal gradient (in Europe); such scenarios include seasonal profiles of water temperature, phytoplankton biomass, detritus, and dissolved organic matter. Model runs were performed for each scenario for 8 hydrophobic chemicals (PCB congeners), with the aim of investigating the influence of scenario characteristics and compound properties on bioavailable concentrations. The key processes were adsorption/uptake by phytoplankton and deposition to sediment of detritus-bound chemicals. The northern scenarios ("Scandinavia" and "UK") showed the highest bioavailable concentrations, with annual maximum/minimum concentration up to 25; in contrast, for example, maximum concentrations in the "Mediterranean" scenario were lower by a factor of 2 to 9 with respect to the northern ones (depending on chemical hydrophobicity), due to the generally higher biomass and carbon levels, and showed only limited seasonal variability (up to a factor of 4). These results highlight the importance of including biomass and organic carbon dynamics in both modelling approaches and scenarios for the evaluation of exposure concentrations in aquatic environments., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In this paper, we reflect on the implications for science, policy and practice of the recently introduced concept of Nature-Based Solutions (NBS), with a focus on the European context. First, we analyse NBS in relation to similar concepts, and reflect on its relationship to sustainability as an overarching framework. From this, we derive a set of questions to be addressed and propose a general framework for how these might be addressed in NBS projects by funders, researchers, policy-makers and practitioners. We conclude that: To realise their full potential, NBS must be developed by including the experience of all relevant stakeholders such that 'solutions' contribute to achieving all dimensions of sustainability. As NBS are developed, we must also moderate the expectations placed on them since the precedent provided by other initiatives whose aim was to manage nature sustainably demonstrates that we should not expect NBS to be cheap and easy, at least not in the short-term., (Copyright © 2016 British Geological Survey, NERC. Published by Elsevier B.V. All rights reserved.)