Showing papers by "Swiss Federal Institute of Aquatic Science and Technology published in 2010"
City College of New York1, University of Michigan2, University of Wisconsin-Madison3, Swiss Federal Institute of Aquatic Science and Technology4, University of Hong Kong5, University of New Hampshire6, Griffith University7, Southern Cross University8, University of Washington9, University of Western Australia10
TL;DR: The first worldwide synthesis to jointly consider human and biodiversity perspectives on water security using a spatial framework that quantifies multiple stressors and accounts for downstream impacts is presented.
Abstract: Protecting the world’s freshwater resources requires diagnosing threats over a broad range of scales, from global to local. Here we present the first worldwide synthesis to jointly consider human and biodiversity perspectives on water security using a spatial framework that quantifies multiple stressors and accounts for downstream impacts. We find that nearly 80% of the world’s population is exposed to high levels of threat to water security. Massive investment in water technology enables rich nations to offset high stressor levels without remedying their underlying causes, whereas less wealthy nations remain vulnerable. A similar lack of precautionary investment jeopardizes biodiversity, with habitats associated with 65% of continental discharge classified as moderately to highly threatened. The cumulative threat framework offers a tool for prioritizing policy and management responses to this crisis, and underscores the necessity of limiting threats at their source instead of through costly remediation of symptoms in order to assure global water security for both humans and freshwater biodiversity.
5,401 citations
ETH Zurich1, Swiss Federal Institute of Aquatic Science and Technology2, University of Maryland, Baltimore3, University College Cork4, University of Le Havre5, Swedish University of Agricultural Sciences6, Lancaster University7, Colorado State University8, Centre national de la recherche scientifique9
TL;DR: It is suggested that changes in species diversity within and across trophic levels can significantly alter decomposition and this happens through various mechanisms that are broadly similar in forest floors and streams.
Abstract: Over 100 gigatons of terrestrial plant biomass are produced globally each year. Ninety percent of this biomass escapes herbivory and enters the dead organic matter pool, thus supporting complex detritus-based food webs that determine the critical balance between carbon mineralization and sequestration. How will changes in biodiversity affect this vital component of ecosystem functioning? Based on our analysis of concepts and experiments of leaf decomposition in forest floors and streams, we suggest that changes in species diversity within and across trophic levels can significantly alter decomposition. This happens through various mechanisms that are broadly similar in forest floors and streams. Differences in diversity effects between these systems relate to divergent habitat conditions and evolutionary trajectories of aquatic and terrestrial decomposers.
1,027 citations
University of British Columbia1, University of Idaho2, Harvard University3, University of California, Santa Barbara4, University of California, Berkeley5, University of Georgia6, Humboldt State University7, University of Minnesota8, Dartmouth College9, Clarkson University10, Yale University11, Imperial College London12, University of Missouri–St. Louis13, Swiss Federal Institute of Aquatic Science and Technology14, University of Bern15, National Evolutionary Synthesis Center16, Oregon State University17, Pontificia Universidad Católica del Ecuador18, Simon Fraser University19
TL;DR: It is suggested that the classical model of adaptive radiation, where morphological evolution is initially rapid and slows through time, may be rare in comparative data.
Abstract: George Gaylord Simpson famously postulated that much of life's diversity originated as adaptive radiations-more or less simultaneous divergences of numerous lines from a single ancestral adaptive type. However, identifying adaptive radiations has proven difficult due to a lack of broad-scale comparative datasets. Here, we use phylogenetic comparative data on body size and shape in a diversity of animal clades to test a key model of adaptive radiation, in which initially rapid morphological evolution is followed by relative stasis. We compared the fit of this model to both single selective peak and random walk models. We found little support for the early-burst model of adaptive radiation, whereas both other models, particularly that of selective peaks, were commonly supported. In addition, we found that the net rate of morphological evolution varied inversely with clade age. The youngest clades appear to evolve most rapidly because long-term change typically does not attain the amount of divergence predicted from rates measured over short time scales. Across our entire analysis, the dominant pattern was one of constraints shaping evolution continually through time rather than rapid evolution followed by stasis. We suggest that the classical model of adaptive radiation, where morphological evolution is initially rapid and slows through time, may be rare in comparative data.
744 citations
TL;DR: For a given oxidant dose, the selective oxidants were more efficient than hydroxyl radicals for transforming ERMs-containing micropollutants, while hydroxy radicals are capable of transforming micropolutants even without ERMs.
656 citations
TL;DR: For the identification and structure elucidation of unknown compounds within a reasonable time frame and with a reasonable soundness, advanced automated software solutions as well as improved prediction systems for theoretical fragmentation patterns, retention times, and ionization behavior are needed.
Abstract: This article provides an overview of the state-of-the-art and future trends of the application of LC–high resolution mass spectrometry to the environmental analysis of polar micropollutants. Highly resolved and accurate hybrid tandem mass spectrometry such as quadrupole/time-of-flight and linear ion trap/orbitrap technology allows for a more reliable target analysis with reference standards, a screening for suspected analytes without reference standards, and a screening for unknowns. A reliable identification requires both high resolving power and high mass spectral accuracy to increase selectivity against the matrix background and for a correct molecular formula assignment to unknown compounds. For the identification and structure elucidation of unknown compounds within a reasonable time frame and with a reasonable soundness, advanced automated software solutions as well as improved prediction systems for theoretical fragmentation patterns, retention times, and ionization behavior are needed.
623 citations
TL;DR: Microscopic results indicate that the Ag-NP are likely transformed to considerably less toxic forms such as Ag2S.
489 citations
TL;DR: It is demonstrated that sampling errors can lead to overinterpretation of measured data and ultimately, wrong conclusions.
Abstract: The analysis of 87 peer-reviewed journal articles reveals that sampling for pharmaceuticals and personal care products (PPCPs) and illicit drugs in sewers and sewage treatment plant influents is mostly carried out according to existing tradition or standard laboratory protocols. Less than 5% of all studies explicitly consider internationally acknowledged guidelines or methods for the experimental design of monitoring campaigns. In the absence of a proper analysis of the system under investigation, the importance of short-term pollutant variations was typically not addressed. Therefore, due to relatively long sampling intervals, potentially inadequate sampling modes, or insufficient documentation, it remains unclear for the majority of reviewed studies whether observed variations can be attributed to “real” variations or if they simply reflect sampling artifacts. Based on results from previous and current work, the present paper demonstrates that sampling errors can lead to overinterpretation of measured d...
436 citations
TL;DR: It is demonstrated that bacteria can modulate flagellar motor output and thus swimming velocity in response to environmental cues and might represent an adaptation to starvation.
411 citations
01 Jan 2010
TL;DR: Because high-risk pharmaceuticals are excreted mainly with feces, urine source separation is not a viable option for reducing the risk potential from hospital wastewater, while a sorption step could be beneficial.
Abstract: In this paper, we evaluated the ecotoxicological potential of the 100 pharmaceuticals expected to occur in highest quantities in the wastewater of a general hospital and a psychiatric center in Switzerland. We related the toxicity data to predicted concentrations in different wastewater streams to assess the overall risk potential for different scenarios, including conventional biological pretreatment in the hospital and urine source separation. The concentrations in wastewater were estimated with pharmaceutical usage information provided by the hospitals and literature data on human excretion into feces and urine. Environmental concentrations in the effluents of the exposure scenarios were predicted by estimating dilution in sewers and with literature data on elimination during wastewater treatment. Effect assessment was performed using quantitative structure-activity relationships because experimental ecotoxicity data were only available for less than 20% of the 100 pharmaceuticals with expected highest loads. As many pharmaceuticals are acids or bases, a correction for the speciation was implemented in the toxicity prediction model. The lists of Top-100 pharmaceuticals were distinctly different between the two hospital types with only 37 pharmaceuticals overlapping in both datasets. 31 Pharmaceuticals in the general hospital and 42 pharmaceuticals in the psychiatric center had a risk quotient above 0.01 and thus contributed to the mixture risk quotient. However, together they constituted only 14% (hospital) and 30% (psychiatry) of the load of pharmaceuticals. Hence, medical consumption data alone are insufficient predictors of environmental risk. The risk quotients were dominated by amiodarone, ritonavir, clotrimazole, and diclofenac. Only diclofenac is well researched in ecotoxicology, while amiodarone, ritonavir, and clotrimazole have no or very limited experimental fate or toxicity data available. The presented computational analysis thus helps setting priorities for further testing. Separate treatment of hospital wastewater would reduce the pharmaceutical load of wastewater treatment plants, and the risk from the newly identified priority pharmaceuticals. However, because high-risk pharmaceuticals are excreted mainly with feces, urine source separation is not a viable option for reducing the risk potential from hospital wastewater, while a sorption step could be beneficial.
369 citations
TL;DR: It is important to develop a better understanding of the biochemistries of the LinA and LinB variants and to use that knowledge to build better variants, because field trials of some bioremediation strategies based on the Lin pathway have yielded promising results but would not yet achieve economic levels of remediation.
Abstract: Summary: Lindane, the γ-isomer of hexachlorocyclohexane (HCH), is a potent insecticide. Purified lindane or unpurified mixtures of this and α-, β-, and δ-isomers of HCH were widely used as commercial insecticides in the last half of the 20th century. Large dumps of unused HCH isomers now constitute a major hazard because of their long residence times in soil and high nontarget toxicities. The major pathway for the aerobic degradation of HCH isomers in soil is the Lin pathway, and variants of this pathway will degrade all four of the HCH isomers although only slowly. Sequence differences in the primary LinA and LinB enzymes in the pathway play a key role in determining their ability to degrade the different isomers. LinA is a dehydrochlorinase, but little is known of its biochemistry. LinB is a hydrolytic dechlorinase that has been heterologously expressed and crystallized, and there is some understanding of the sequence-structure-function relationships underlying its substrate specificity and kinetics, although there are also some significant anomalies. The kinetics of some LinB variants are reported to be slow even for their preferred isomers. It is important to develop a better understanding of the biochemistries of the LinA and LinB variants and to use that knowledge to build better variants, because field trials of some bioremediation strategies based on the Lin pathway have yielded promising results but would not yet achieve economic levels of remediation.
330 citations
TL;DR: Results suggest that negative effects of hatchery rearing are not just a concern but undeniably present in many aquaculture species, and there is a chance to improve hatchery practices and mitigate the negative effects on wild stocks, although scientific data supporting the positive effect on stock enhancement are largely missing at this moment.
TL;DR: The results support the use of ATP analysis for both routine monitoring and research purposes, and contribute towards a better interpretation of ATP data.
TL;DR: Quantitative analysis of the effects of photolytic and photocatalytic treatment processes on the antibacterial activity of ciprofloxacin solutions under controlled laboratory conditions indicates that the UVA-TiO(2) photocatalysis is the most energy efficient process for achieving cIProfl oxacin inactivation under laboratory conditions.
TL;DR: The results showed that the complementary use of the target and non-target screening methods allowed for a more comprehensive interpretation of the TPs generated than either would have provided individually.
Abstract: During wastewater treatment, many organic micropollutants undergo microbially mediated reactions resulting in the formation of transformation products (TPs). Little is known on the reaction pathways that govern these transformations or on the occurrence of microbial TPs in surface waters. Large sets of biotransformation data for organic micropollutants would be useful for assessing the exposure potential of these TPs and for enabling the development of structure-based biotransformation prediction tools. The objective of this work was to develop an efficient procedure to allow for high-throughput elucidation of TP structures for a broad and diverse set of xenobiotics undergoing microbially mediated transformation reactions. Six pharmaceuticals and six pesticides were spiked individually into batch reactors seeded with activated sludge. Samples from the reactors were separated with HPLC and analyzed by linear ion trap-orbitrap mass spectrometry. Candidate TPs were preliminarily identified with an innovative...
TL;DR: A proteomic study of protein-nanoparticle interactions suggests a probable mechanism for adhesion of proteins to the most commonly used commercial nanoparticles and highlights the potential effect of nanoparticle surface coating on bioavailability.
Abstract: Here we describe results from a proteomic study of protein−nanoparticle interactions to further the understanding of the ecotoxicological impact of silver nanoparticles (AgNPs) in the environment. We identified a number of proteins from Escherichia coli that bind specifically to bare or carbonate-coated AgNPs. Of these proteins, tryptophanase (TNase) was observed to have an especially high affinity for both surface modifications despite its low abundance in E. coli. Purified TNase loses enzymatic activity upon associating with AgNPs, suggesting that the active site may be in the vicinity of the binding site(s). TNase fragments with high affinities for both types of AgNPs were identified using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. Differences in peptide abundance/presence in mass spectra for the two types of AgNPs suggest preferential binding of some protein fragments based on surface coating. One high-binding protein fragment contained a residue (Arg103)...
TL;DR: The substantial temperature-dependent methane emissions discovered in this 90-year-old reservoir indicate that temperate water bodies can be an important but overlooked methane source.
Abstract: Methane emission pathways and their importance were quantified during a yearlong survey of a temperate hydropower reservoir. Measurements using gas traps indicated very high ebullition rates, but due to the stochastic nature of ebullition a mass balance approach was crucial to deduce system-wide methane sources and losses. Methane diffusion from the sediment was generally low and seasonally stable and did not account for the high concentration of dissolved methane measured in the reservoir discharge. A strong positive correlation between water temperature and the observed dissolved methane concentration enabled us to quantify the dissolved methane addition from bubble dissolution using a system-wide mass balance. Finally, knowing the contribution due to bubble dissolution, we used a bubble model to estimate bubble emission directly to the atmosphere. Our results indicated that the total methane emission from Lake Wohlen was on average >150 mg CH4 m−2 d−1, which is the highest ever documented for a midlati...
TL;DR: This study showed that water stagnation in household pipes results in considerable microbial changes and emphasizes the need for the development of good material validation methods, recommendations and spot tests for in-house water installations.
TL;DR: It can be safely concluded that in catchments of mixed land use, the contributions of biocide and pesticide inputs into surface waters from urban areas are at least as important as those from agricultural areas.
TL;DR: In this article, a GIS-based version of the EPIC model, GEPIC, is used for the estimation of consumptive water use in cropland on a global scale with a spatial resolution of 30 arc-minutes.
TL;DR: The current status of FCM in the field of microbiology is reviewed, focusing on its recent applications in aquatic microbiology, which range from straightforward total cell counts to community structure analysis, and further extend to physiological analysis at a single-cell level.
TL;DR: In this article, the authors presented a method for high-resolution vertical temperature profiling in surface-water sediments for detailed quantification of seepage flux over depth and time.
TL;DR: An input-output analysis based on the water footprint accounting framework is built to account for WF and virtual water trade of final consumptive products in the water stressed Haihe River basin in China and showed that the basin was silently importing virtual water through the trade of raw and processed food commodities under the background of the whole economic circulation.
Abstract: The virtual water strategy which advocates importing water intensive products and exporting products with low water intensity is gradually accepted as one of the options for solving water crisis in severely water scarce regions. However, if we count the virtual water embodied in imported products as the water saved for a region, we might overestimate the saving by including the virtual water that is later re-exported in association with the proceeded products made from the originally imported products. This problem can be avoided by accounting for the saved water through calculating water footprint (WF) in domestic final consumptive products. In this paper, an input−output analysis (IOA) based on the water footprint accounting framework is built to account for WF and virtual water trade of final consumptive products in the water stressed Haihe River basin in China for the year 1997, 2000, and 2002. The input−output transaction tables of the three years are constructed. The results show WF of 46.57, 44.52,...
TL;DR: Flow cytometry allows fast and easy quantification of microbial growth of natural bacterial communities, including "uncultivable" members, under environmental conditions, and when combined with strain-specific fluorescent immunoprobes, this technique allows investigation of the growth and competition with the indigenous microbial flora.
TL;DR: Modelling might be sufficient to estimate daily average exposure concentrations for compounds that are either recalcitrant or whose degradation and sorption behaviour can be predicted with confidence based on laboratory experiments, and chemical measurements should be reserved for assessing point sources.
TL;DR: In this article, the local coordination and structure of Fe(III)-precipitates formed in aerated Fe(II)- and As(III)containing water (buffered to pH 7 by 8mM bicarbonate) using synchrotron-based X-ray absorption spectroscopy (XAS) at the K -edges of Fe, P, Ca, and As.
TL;DR: In the tertiary effluent, the highest average concentrations were determined for mecoprop which was at comparable levels as the pharmaceuticals diclofenac and sulfamethoxazole but 1-2 orders of magnitude higher than the other biocidal compounds.
TL;DR: Struvite formation in a CSTR (continuously stirred tank reactor) process was shown to be a reliable stable process that does not require any pH control and a method based on conductivity measurement is presented to estimate ionic strength, which is needed for equilibrium calculations.
TL;DR: The amount of total As(III) formed during soil reduction was linearly correlated to the amount oftotal Fe(II) formed, indicating that the rate of As(V) reduction was controlled by the rates of microbial Fe(III] (hydr)oxide reduction.
Abstract: Arsenic (As) in soils and sediments is commonly mobilized when anoxic conditions promote microbial iron (Fe) and As reduction. Recent laboratory studies and field observations have suggested a decoupling between Fe and As reduction and release, but the links between these processes are still not well understood. In microcosm experiments, we monitored the formation of Fe(II) and As(III) in the porewater and in the soil solid-phase during flooding of a contaminated floodplain soil at temperatures of 23, 14, and 5 °C. At all temperatures, flooding induced the development of anoxic conditions and caused increasing concentrations of dissolved Fe(II) and As(III). Decreasing the temperature from 23 to 14 and 5 °C strongly slowed down soil reduction and Fe and As release. Speciation of As in the soil solid-phase by X-ray absorption spectroscopy (XAS) and extraction of the Fe(II) that has formed by reductive Fe(III) (hydr)oxide dissolution revealed that less than 3.9% of all As(III) and less than 3.2% of all Fe(II...
TL;DR: The phenomenon of flux stabilization opens interesting possibilities for application, for instance in simple and low-cost ultrafiltration systems for decentralized drinking water treatment in developing and transition countries, independent of energy supply, chemicals, or complex process control.
TL;DR: A general introduction to the concept of TK-TD modelling for environmental scientists is provided and opportunities as well as current limitations are discussed.
Abstract: Toxicokinetic-toxicodynamic (TK-TD) models simulate the processes that lead to toxicity at the level of organisms over time. These dynamic simulation models quantify toxicity, but more importantly they also provide a conceptual framework to better understand the causes for variability in different species' sensitivity to the same compound as well as causes for different toxicity of different compounds to the same species. Thus TK-TD models bring advantages for very diverse ecotoxicological questions as they can address two major challenges: the large number of species that are potentially affected and the large number of chemicals of concern. The first important benefit of TK-TD models is the role that they can play to formalize established knowledge about toxicity of compounds, sensitivity of organisms, organism recovery times and carry-over toxicity. The second important aspect of TK-TD models is their ability to simulate temporal aspects of toxicity which makes them excellent extrapolation tools for risk assessment of fluctuating or pulsed exposures to pollutants. We provide a general introduction to the concept of TK-TD modelling for environmental scientists and discuss opportunities as well as current limitations.