In this paper, we present an approach to modeling the internal psychological processes of resource-using individuals. From results of relevant resource-use literature, we identified nine essential influence factors and their interactions: communication, feedback about other's harvest, trust, social value orientations, group identity, resource feedback, resource uncertainty, payoff, and perceived cause of resource abundance or scarcity. Based on these findings, we built the Social-Ecological Relevance Model of resource use. Comparison of simulation results with data of real experiments shows that the developed model is an appropriate internal model for agents in resource-use simulations. We ran simulations targeting to trace individual dynamics in a group of five agents that used from the same resource. It could be show that although some agents under low uncertainty overuse the resource the majority of the group is using it in a sustainable way and thus stabilizing the resource on a higher level. Finally, we discuss the implications for future research.

Vielfach werden Spurenstoffe in Kläranlagen nur teilweise zurückgehalten. Der restliche Teil und mögliche Abbauprodukte gelangen mit dem geklärten Abwasser in die Gewässer. Welche technischen Optionen stehen zur Verfügung, um die Eliminationsleistung zu verbessern? Ein Einblick in die moderne Verfahrenstechnik.

L’idée de base de la désinfection de l’eau par le rayonnement solaire est simple: après un séjour de six heures en plein soleil, l’eau contenue dans des bouteilles en polyéthylène est débarrassée de tout germe. Mais malgré sa simplicité et ses avantages sanitaires indéniables, cette méthode ne se diffuse pas aussi rapidement qu’on pourrait le penser.

D’énormes quantités de carbone sont emmagasinées dans les sédiments lacustres. Ce piégeage permet de retirer une partie du CO<SUB>2</SUB> de l’atmosphère et contribue donc à limiter l’effet de serre. Une équipe de chercheurs de l’Eawag vient de déterminer comment le carbone était stabilisé pour de longues périodes dans les sédiments lacustres.

Le modèle de simulation ERIMO (Ecological River Model) que nous avons développé permet de décrire d’importants processus se déroulant dans les cours d’eau. Pour le mettre au point, une modélisation des algues et invertébrés vivant au fond du lit a été réalisée et les incertitudes de modélisation ont été prises en compte.

Les nitrosamines sont des substances réputées cancérigènes qui peuvent être absorbées avec la nourriture ou se former par réaction chimique au niveau de l’estomac. Au vu de rapports nord-américains faisant état d’une contamination parfois importante de l’eau potable, nous avons cherché à savoir si ce bien vital pouvait également être menacé en Suisse.

De plus en plus de produits du quotidien renferment des nanoparticules synthétiques. Nos connaissances sur leur émission et leur comportement dans l’environnement sont cependant encore très limitées. En outre, on ignore aussi très largement quelles sont les quantités de nanoparticules naturellement présentes, notamment dans l’eau potable. Nous avons tenté de dresser un état des lieux.

Flow cytometry (FCM) is rapidly becoming an essential tool in the field of aquatic microbiology. It provides opportunities for microbial analysis at both the community and single-cell levels. Compared with other techniques, FCM facilitates rapid data acquisition and multi-parameter analysis, leading to increased popularity and widespread applications. Here, we briefly review the current status of FCM in the field of microbiology, focusing on its recent applications in aquatic microbiology. These developments range from straightforward total cell counts to community structure analysis, and further extend to physiological analysis at a single-cell level. Exciting future prospects for the applications of FCM in aquatic microbiology are also discussed based on current scientific and practical needs.

The degree to which a water sample can potentially support the growth of human pathogens was evaluated. For this purpose, a pathogen growth potential (PGP) bioassay was developed based on the principles of conventional assimilable organic carbon (AOC) determination, but using pure cultures of selected pathogenic bacteria (<em>Escherichia coli</em> O157, <em>Vibrio cholerae</em>, or <em>Pseudomonas aeruginosa</em>) as the inoculum. We evaluated 19 water samples collected after different treatment steps from two drinking water production plants and a wastewater treatment plant and from ozone-treated river water. Each pathogen was batch grown to stationary phase in sterile water samples, and the concentration of cells produced was measured using flow cytometry. In addition, the fraction of AOC consumed by each pathogen was estimated. Pathogen growth did not correlate with dissolved organic carbon (DOC) concentration and correlated only weakly with the concentration of AOC. Furthermore, the three pathogens never grew to the same final concentration in any water sample, and the relative ratio of the cultures to each other was unique in each sample. These results suggest that the extent of pathogen growth is affected not only by the concentration but also by the composition of AOC. Through this bioassay, PGP can be included as a parameter in water treatment system design, control, and operation. Additionally, a multilevel concept that integrates the results from the bioassay into the bigger framework of pathogen growth in water is discussed. The proposed approach provides a first step for including pathogen growth into microbial risk assessment.

Verschiedene technische Aufrüstungen in Kläranlagen, die zu einer verbesserten Eliminierung der Spurenstoffe führen können, sind derzeit in Diskussion. Mit welchen chemischen und biologischen Indikatoren aber kann der Erfolg dieser zusätzlichen Reinigungsverfahren beurteilt werden?

Chemische Stoffe können in der Umwelt zu Substanzen umgewandelt werden, die stabiler, besser wasserlöslich und in einzelnen Fällen gar toxischer sind als die Ausgangsverbindung. Die Eawag entwickelt Methoden, um das Risiko dieser Umwandlungsprodukte besser einschätzen zu können.

Nanopartikel werden heute bereits breit eingesetzt. Da ist es nur wahrscheinlich, dass sie früher oder später auch in der Umwelt landen. Studien der Eawag wiesen dies nun erstmals nach und zeigen darüber hinaus, auf welche Weise sich synthetische Nanopartikel negativ auf Gewässerorganismen auswirken können.

Die Dosis macht die Wirkung. Ist das wirklich so? Und wie lange dauert es, bis Organismen sich wieder erholt haben? Was passiert, wenn mehrere Schadstoffbelastungen aufeinander folgen? Diese und andere Fragen versuchen wir mit toxikokinetisch/toxikodynamischen Modellen und Experimenten zu beantworten.

Biosolids recovered from yard-scale vertical-flow constructed wetlands used for fæcal sludge dewatering in Cameroon, were analyzed to assess their degree of maturity, nutrient and heavy metals contents, as well as their hygienic quality. Six beds were loaded weekly at nominal loading rate of 100, 200, and 300 kg TS/m<SUP>2</SUP>/year. The quality of the biosolids accumulated in the beds was monitored during 6 additional months of resting period prior to final harvest. Results showed that C/N ratio (11.3), humification index (14%), humification rate (1.8%), and degree of polymerization (3.7) of the biosolids generated were comparable to those of mature composts. Biosolids quality appeared to having high fertilizing value (N: 2%, P<SUB>2</SUB>O<SUB>5</SUB>: 2.3%, CaO: 1%, MgO: 0.14%, K<SUB>2</SUB>O: 0.03, and Na<SUB>2</SUB>O: 0.09%) with low heavy metals contamination (63, 14, 26, 2.4, 575, 703, 186, and 32 mg/kg for Pb, Ni, Cr, Cd, Cu, Zn, Mn, and Se, respectively). The concentration of fertile ascaris was reduced from 40 eggs/g TS after one month storage to <4 eggs/g TS after six month of storage, a level which does not significantly increase health risk exposure as compare to the WHO guidelines.

This paper presents the potentials and performance of combined treatment of faecal sludge (FS) and municipal solid waste (SW) through co-composting. The objectives were to investigate the appropriate SW type, SW/FS mixing ratio and the effect of turning frequency on compost maturity and quality. Solid waste (SW, as market waste, MW, or household waste, HW) was combined with dewatered FS in mixing ratios of 2:1 and 3:1 by volume and aerobically composted for 90 days. Four composting cycles were monitored and characterised to establish appropriate SW type and mixing ratio. Another set of five composting cycles were monitored to test two different turning frequencies: (i) once in 3–4 days during the thermophilic phase and 10 days during maturation phase and (ii) once in every 10 days throughout the composting period. Samples were taken at every turning and analysed for total solids (TS), total volatile solids (TVS), total organic carbon (TOC), electrical conductivity (EC), pH, ammonium and nitrate nitrogen (NH<SUB>4</SUB>–N and NO<SUB>3</SUB>–N) and total Kjeldahl nitrogen (TKN). Temperature, C/N ratio, NO<SUB>3</SUB>–N/NH<SUB>4</SUB>–N ratio and cress planting trials were chosen as maturity indicators. Result showed a preference of MW over HW and mixing ratio of 2:1 over 3:1. There was no significant effect of different turning frequencies on the temperature changes and the quality of mature compost. The final product contained C/N ratio of 13 and NO<SUB>3</SUB>/NH<SUB>4</SUB>-ratio of about 7.8, while TVS was about 21% TS and the NH<SUB>4</SUB>–N content was reduced to 0.01%. A co-composting duration of 12 weeks was indicated by the cress test to achieve a mature and stable product. The turning frequency of 10 days is recommended as it saves labour and still reaches safe compost with fairly high nutrient content.

Black carbon (BC) and mineral dust aerosols were analyzed in an ice core from the Colle Gnifetti glacier (Monte Rosa, Swiss-Italian Alps, 45°55′N, 7°52′E, 4455 m above sea level) using chemical and optical methods. The resulting time series obtained from this summer ice record indicate that BC transport was primarily constrained by regional anthropogenic activities, i.e., biomass and fossil fuel combustion. More precisely, the <I>δ</I><SUP>13</SUP>C composition of BC suggests that wood combustion was the main source of preindustrial atmospheric BC emissions (C3:C4 ratio of burnt biomass of 75:25). Despite relatively high BC emissions prior to 1570, biomass burning activity and especially C<SUB>4</SUB> grassland burning abruptly dropped between 1570 and 1750 (C3:C4 ratio of burnt biomass of 90:10), suggesting that agricultural practices strongly decreased in Europe during this cold period of the “Little Ice Age” (LIA). On the other hand, optical analysis revealed that the main source for atmospheric dust transport to the southern parts of the Alps during summer months was driven by large-scale atmospheric circulation control on the dust export from the northern Saharan desert. This southern aerosol source was probably associated with global-scale hydrologic changes, at least partially forced by variability in solar irradiance. In fact, periods of enhanced Saharan dust deposition in the ice core (around 1200–1300, 1430–1520, 1570–1690, 1780–1800, and after 1870) likely reflect drier winters in North Africa, stronger North Atlantic southwesterlies, and increased spring/summer precipitation in west-central Europe. These results, therefore, suggest that the climatic pejorations and the resulting socioeconomic crises, which occurred in Europe during periods of the LIA, could have been indirectly triggered by large-scale meridional advection of air masses and wetter summer climatic conditions.

The increasing thirst for energy to fuel its fast growing economy has made China keen to explore the potential of modern form of bioenergy, biofuel. This study investigates the land and water requirements of biofuel in China with reference to the government biofuel development plans for 2010 and 2020. The concept of land and water footprints of biofuel is applied for the investigation. The result shows that the current level of bioethanol production consumes 3.5–4% of total maize production of the country, reducing market availability of maize for other uses by about 6%. It is projected that depending on the types of feedstock, 5–10% of the total cultivated land in China would need to be devoted to meet the biofuel production target of 12 million metric tons for the year 2020. The associated water requirement would amount to 32–72 km<SUP>3</SUP> per year, approximately equivalent to the annual discharge of the Yellow River. The net contribution of biofuel to the national energy pool could be limited due to generally low net energy return of conventional feedstocks. The current biofuel development paths could pose significant impacts on China's food supply and trade, as well as the environment.

In many river basins, floodplain soils have accumulated a variety of metal contaminants, which might be released during periods of flooding. We investigated the dynamics of copper, cadmium, lead, zinc, and nickel in a contaminated freshwater floodplain soil under a realistic sulfate-limited flooding regime in microcosm experiments. We found that most contaminants were initially mobilized by processes driven by the reductive dissolution of Fe(III) and Mn(IV, III) (hydr)oxides. Subsequently, bacterial sulfate respiration resulted in the transformation of the entire available sulfate (2.3 mmol/kg) into chromous reducible sulfur (CRS). Cu K-edge X-ray absorption fine structure (XAFS) spectroscopy revealed that the soil Cu speciation changed from predominantly Cu(II) bound to soil organic matter (SOM) intermittently to 14% metallic Cu(0) and subsequently to 66% copper sulfide (Cu<I><SUB>x</SUB></I>S). These Cu<I><SUB>x</SUB></I>S precipitates accounted for most of the formed CRS, suggesting that Cu<I><SUB>x</SUB></I>S was the dominant sulfide phase formed in the flooded soil. Sequential metal extractions, in agreement with CRS results, suggested that easily mobilizable Cd was completely and Pb partially sequestered in sulfide precipitates, controlling their dissolved concentrations to below detection limits. In contrast, Zn and Ni (as well as Fe) were hardly sequestered into sulfide phases, so that micromolar levels of dissolved Zn and Ni (and millimolar dissolved Fe(II)) persisted in the reduced soil. The finding that Cu, Cd, and Pb were sequestered (but hardly any Zn, Ni, and Fe) is consistent with the thermodynamically predicted sulfide ladder following the increasing solubility products of the respective metal sulfides. The observation that Cd and Pb were sequestered in sulfides despite the presence of remaining SOM-bound Cu(II) suggested that the kinetics of Cu(II) desorption, diffusion, and/or Cu<I><SUB>x</SUB></I>S precipitation interfered with the sulfide ladder. We conclude that the dynamics of multiple metal contaminants are intimately coupled under sulfate limitation by the relative thermodynamic stabilities and formation kinetics of the respective metal sulfides.

In order to better understand the long-term speciation and fractionation of Zn in soils, we investigated three soils naturally enriched in Zn (237–864 mg/kg Zn) from the weathering of Zn-rich limestones (40–207 mg/kg Zn) using extended X-ray absorption fine structure (EXAFS) spectroscopy and sequential extractions. The analysis of bulk EXAFS spectra by linear combination fitting (LCF) indicated that Zn in the oolitic limestones was mainly present as Zn-containing calcite (at site Dornach), Zn-containing goethite (Gurnigel) and Zn-containing goethite and sphalerite (Liestal). Correspondingly, extraction of the powdered rocks with 1 M NH<SUB>4</SUB>-acetate at pH 6.0 mobilized only minor fractions of Zn from the Gurnigel and Liestal limestones (<30%), but most Zn from the Dornach rock (81%). In the Dornach soil, part of the Zn released from the dissolving limestone was subsequently incorporated into pedogenic hydroxy-interlayered vermiculite (Zn-HIV, ~30%) and Zn-containing kaolinite (~30%) and adsorbed or complexed by soil organic and inorganic components (~40%). The Gurnigel and Liestal soils contained substantial amounts of Zn-containing goethite (~50%) stemming from the parent rock, smaller amounts (~20%) of Zn-containing kaolinite (and possibly Zn-HIV), as well as adsorbed or complexed Zn-species (~30%). In the soil from Liestal, sphalerite was only found in trace amounts, indicating its dissolution during soil formation. In sequential extractions, large percentages of Zn (~55–85%) were extracted in recalcitrant extraction steps, confirming that Zn-HIV, Zn-containing kaolinite and Zn-containing goethite are highly resistant to weathering. These Zn-bearing phases thus represent long-term hosts for Zn in soils over thousands of years. The capability of these phases to immobilize Zn in heavily contaminated soils may however be limited by their uptake capacity (especially HIV and kaolinite) or their abundance in soil.

Reaching the Millennium Development Goals for Sanitation is a challenge. Numerous technological innovations have been developed in the last decade. With innovation comes also an increasing lack of consistency and increased communication difficulties. This is especially true in rural and peri-urban<br/>West-Africa, where there is a desperate need for feasible sanitation systems and technologies which in the site specific context can achieve the intende objectives of health hygiene and well-being. NETSSAF (Network for the development of Sustainable Approaches for Large Scale Implementation<br/>of Sanitation in Africa) has developed a method for organizing and defining sanitation systems. Main goal is to assist in the decision maiking process to avoid fixed mind sets towards conventional solutions which to-date have not always shown to be the best choice in a site specific context. The systematization shall also help avoid that some waste components (e.g. greywater or faecal sludge form on-site technologies) are forgotten in the planning and master plan development.

The primary production in meromictic Lake Kivu is sustained by external nutrient inputs and by internal loading due to upwelling caused by sub-aquatic sources. We present here the results of external loading of phosphorus (P), nitrogen (N) and silica (Si) by rivers and atmospheric deposition measured from 2006 to 2008. These external inputs are compared to internal loading. The input of soluble-reactive P (SRP), supplied in equal parts from rivers and atmospheric deposition, adds up to 230 t P yr<SUP>–1</SUP>, 20 times less than total P load. Ammonium (mainly via rainwater) and nitrate (mainly via rivers) are primary sources of the dissolved N load (5400 t N yr<SUP>–1</SUP>), with both species contributing ∼50%. Dissolved Si input (40,000 t Si yr<SUP>–1</SUP>) is unique in that only ∼60% enters by rivers, while the remaining ∼40% comes from sub-aquatic sources and atmospheric deposition is negligible. Based on the molar nutrient ratios, we identify P as the limiting factor for algae production. Despite the strong anthropogenic impact on the catchment and the high particle erosion (74 t km<SUP>–2</SUP> yr<SUP>–1</SUP>), the area-specific nutrient mobilization is rather low. The external nutrient input is therefore not the cause for the reported increase of methane production in the last decades. External loading to the epilimnion plays a lesser role for all three nutrients (∼10% for SRP, ∼25% for dissolved N and ∼45% for dissolved Si), as compared to the lake-internal loading by upwelling (90%, 75% and 55%, respectively). Lake Kivu, therefore, is similar to other East African large lakes in that the internal loading exceeds the external loading. Despite the substantial uncertainty of the load estimates of up to 50%, we can conclude that the observed nutrient input is consistent with the primary production of 260 g C m<SUP>–2</SUP> yr<SUP>–1</SUP> recently measured by Sarmento et al. (2006) and also consistent with the lake-internal fluxes established by Pasche et al. (in press).

Infrastructure sectors in general, and urban water management in particular, have developed over the past couple of decades within the confines of a rather narrow and stable socio-technical regime. Nowadays, these infrastructures are increasingly confronted with uncertain context conditions, a broadened spectrum of technological alternatives and an increasing heterogeneity of value positions. As a consequence, the longterm sustainability of these sectors has been questioned by many commentators. Of particular importance is the way strategic decisions are made. Current approaches tend to block important opportunities for sustainable transformation. It is argued here that a more reflexive, discursive and participative approach to strategic planning is needed. The paper introduces «Regional Infrastructure Foresight» (RIF) as a method which combines foresight on regional framework conditions with a stakeholder assessment of a broad range of system options. The paper presents the methodology in some detail and discusses the main lessons learned through three empirical applications in the Swiss sanitation sector. Based on these experiences, it is argued that strategic decision making in infrastructures is of high relevance for regional policy and therefore warrants more attention in future research in economic and political geography.

The isotope composition of zinc (Zn) was determined in settling particles collected monthly over a year in the hypolimnion of the eutrophic Lake Greifen (Switzerland) in order to explore the potential of this novel isotope system as a proxy for biogeochemical processes in aqueous environments. Significant variation in δ⁶⁶Zn_JMC3-0749L of 0.9%₀ (where δ⁶⁶Zn_JMC3-0749L = [{⁶⁶Zn: ⁶⁴Zn}_sample/{⁶⁶Zn: ⁶⁴Zn} _JMC3-0749L -1] × 1000) was found throughout the seasonal cycle of productivity. The most negative δ⁶⁶Zn_JMC3-0749L, values (down to -0.66%o ± 0.08%₀) were observed during the productive summer period from June to September, when the Zn in the settling particles was predominantly associated with organic material, and when Zn concentrations in the epilimnion were lowest. This observation is likely explained with preferential uptake of the light Zn isotopes during algal growth. During the other months, the Zn in the sediment traps showed higher δ⁶⁶Zn values, reflecting increasing contributions of anthropogenic or lithogenic components. The average isotopic signature of the settling particles during the autumn-winter-spring period (∼ -0.2% ₀ for δ⁶⁶Zn_JMC3-047L) was somewhat lower than typical for anthropogenic and natural sources, and this possibly reflects the effect of the preferential adsorption of lighter dissolved Zn isotopes onto the settling particles. We suggest that Rayleigh fractionation plays a minor role in controlling the isotopic composition of the settling particles in the lake. Our work demonstrates the presence of an obvious seasonal cycle in δ⁶⁶Zn, and this suggests that Zn isotopes can be employed to study nutrient utilization and other biogeochemical processes in lakes and other aquatic environments.

Heterotrophic microorganisms are widely recognized as crucial components of ecosystems; yet information on their community structure and dynamics in benthic freshwater habitats is notably scarce. Using denaturing gradient gel electrophoresis (DGGE), we determined the composition of bacterial and fungal communities in a freshwater marsh over four seasons. DGGE revealed diverse bacterial communities in four contrasting microhabitats. The greatest compositional differences emerged between water-column and surface-associated bacteria, although communities associated with sediment also differed from those on plant litter and epiphytic biofilms. Sequences of bacterial clones derived from DGGE bands belonged to the <I>Alphaproteobacteria</I> (31%), <I>Actinobacteria</I> (19%) and <I>Bacteriodetes</I> (19%). <I>Betaproteobacteria</I> were notably absent. Fungal clones obtained from leaf litter were mainly <I>Ascomycota</I>, but two members of the <I>Basidiomycota</I> were also identified. Overall, habitat type was the most important factor explaining variation in bacterial communities among samples, whereas temporal patterns in community composition were less pronounced in spite of large seasonal variation in environmental conditions such as temperature. The observed differences among bacterial communities in different microhabitats were not caused by random variation, but rather appeared to be determined by habitat characteristics, as evidenced by largely congruent community profiles of replicate samples taken at 10–100 m distances within the marsh.

Little is known about the significance of hospitals as point sources for emission of organic micropollutants into the aquatic environment. A mass flow analysis of pharmaceuticals and diagnostics used in hospitals was performed on the site of a representative Swiss cantonal hospital. Specifically, we analyzed the consumption of iodinated X-ray contrast media (ICM) and cytostatics in their corresponding medical applications of radiology and oncology, respectively, and their discharge into hospital wastewater and eventually into the wastewater of the municipal wastewater treatment plant. Emission levels within one day and over several days were found to correlate with the pharmacokinetic excretion pattern and the consumed amounts in the hospital during these days. ICM total emissions vary substantially from day to day from 255 to 1259 g/d, with a maximum on the day when the highest radiology treatment occurred. Parent cytostatic compounds reach maximal emissions of 8−10 mg/d. A total of 1.1%, 1.4%, and 3.7% of the excreted amounts of the cytostatics 5-fluorouracil, gemcitabine, and 2′,2′-difluorodeoxyuridine (main metabolite of gemcitabine), respectively, were found in the hospital wastewater, whereas 49% of the total ICM was detected, showing a high variability among the compounds. These recoveries can essentially be explained by the high amount administered to out-patients (70% for cytostatics and 50% for ICM); therefore, only part of this dose is expected to be excreted on-site. In addition, this study emphasizes critical issues to consider when sampling in hospital sewer systems. Flow proportional sampling over a longer period is crucial to compute robust hospital mass flows.

Antibiotics may be released to soils during the application of manure as fertiliser to land. The compounds may subsequently be transported to and contaminate groundwater and surface waters. This paper describes a series of lysimeter-based studies to explore the leaching behaviour of three veterinary antibiotics (sulfachloropyridazine, oxytetracycline and tylosin) under different conditions that could occur in the agricultural environment. The specific objectives were to: (1) explore the influence of slurry amendment and incorporation on leaching; (2) assess the effects of climate on leaching behaviour; and (3) evaluate the predictive capability of a leaching model used in the regulatory assessment of veterinary medicines. Sulfachloro-pyridazine was detected sporadically in leachate at concentrations up to 0.66 μg L<SUP>−1</SUP> under typical irrigation conditions and more frequently at concentrations up to 8.5 μg L<SUP>−1</SUP> under extreme irrigation conditions. Incorporation and timing of rainfall had no effect on leaching behaviour. Oxytetracycline and tylosin were not detected in any leachate samples. These differences in behaviour were explained by the sorption and persistence characteristics of the compounds. Comparison of the experimental measurements with simulations from the leaching model indicated that the model greatly underestimates the transport of antibiotics to groundwater which raises questions over the application of these models in the regulatory risk assessment process.

<I>Background, aim, and scope</I> Pharmaceutically active substances are a class of emerging contaminants, which has led to increasing concern about potential environmental risks. After excretion, substantial amounts of unchanged pharmaceuticals and their metabolites are discharged into domestic wastewaters. The absence of data on the environmental exposure in Eastern Europe is significant, since use patterns and volumes differ from country to country. In Romania, the majority of wastewater, from highly populated cities and industrial complex zones, is still discharged into surface waters without proper treatment or after inefficient treatment. In respect to this, it is important to determine the environmental occurrence and behavior of pharmaceuticals and personal care products (PPCPs) in wastewaters and surface waters. The objective of the present study was to investigate the occurrence of selected PPCPs during the transport in the Somes River by mass flow analysis before and after upgrading a municipal wastewater treatment plant (WWTP) in Cluj-Napoca, which serves 350,000 inhabitants and is the largest plant discharging into the Somes River. The concentrations of PPCPs at Cluj-Napoca can be correlated with the high population and a high number of hospitals located in the catchment area leading to higher mass flows. The results of this study are expected to provide information, with respect to the Romanian conditions, for environmental scientists, WWTP operators, and legal authorities. The data should support the improvement of existing WWTPs and implementation of new ones where necessary and, therefore, minimize the input of contaminants into ambient waters.<BR/><I>Materials and methods</I> The PPCPs were selected on the basis of consumption at the regional scale, reported aquatic toxicity, and the suitability of the gas chromatography/mass spectrometry (GC/MS) method for the determination of the compounds at trace levels. The studied PPCPs, caffeine (stimulant), carbamazepine (antiepileptic), pentoxifylline (anticoagulant), cyclophosphamide (cytostatic), ibuprofen (analgesic), and galaxolide (musk fragrance), were determined in samples of the Somes River. The analytes were enriched by solid-phase extraction and subsequently determined by GC/MS. Caffeine, pentoxifylline, and galaxolide were determined underivatized, whereas the acidic pharmaceuticals carbamazepine, cyclophosphamide, and ibuprofen were determined after derivatization with <I>N</I>-methyl-<I>N</I>-(trimethylsilyl)-trifluoroacetamide.<BR/><I>Results and discussion</I> The concentrations in the Somes River varied from below 10 ng/L up to 10 μg/L. A substantial decrease of the exposure in the Somes River could be observed due to the upgrade of the municipal WWTP in Cluj-Napoca. The loads in the river stretch between Cluj-Napoca and Dej (Somes Mic) varied strongly: caffeine (400–2,000 g/day), carbamazepine (78–213 g/day), galaxolide (140–684 g/day), ibuprofen (84–108 g/day). After the upgrade of the WWTP Cluj-Napoca, the concentrations in the Somes of caffeine, pentoxifylline, cyclophosphamide, galaxolide, and tonalide were significantly reduced (over 75%). One might be cautious comparing both studies because the relative efficiency of the WWTP’s removal of PPCP was not evaluated. However, the significantly lower concentrations of most compounds after the upgrade of the WWTP Cluj-Napoca allow one to infer that the technical measures at the source substantially reduced inputs of contaminants to the receiving river. Dej loads of the poorly biodegradable substance carbamazepine increased by a factor of 2–3 as a result of wastewater discharges into the river. The disproportionate increase in caffeine loads by a factor of 4 below Cluj-Napoca indicates inputs of untreated wastewater from the Somes Mare due to the discharge of untreated wastewater derived from Bistrita, Nasaud, and Beclean (115,000 inhabitants).<BR/><I>Conclusions</I> The relative contribution of treated and untreated wastewater in surface water might be assessed by measuring chemical markers. Recalcitrant pharmaceuticals like carbamazepine are suitable as chemical markers for estimating the relative contribution of wastewater in surface water. The easily degradable caffeine might be a good indicator for raw sewage and hardly treated wastewaters.<BR/><I>Recommendations and perspectives</I> Municipal WWTPs have the potential of a significant contribution in reducing the load of contaminants to ambient waters. The efficiency of the wastewater treatment in Cluj-Napoca improved considerably after the upgrade of the WWTP. Therefore, it is crucial that several WWTPs must be implemented or improved in the Somes Valley Watershed in order to reduce the discharge of contaminants in the Somes River from these point sources.

In recent years, the wind power sector has begun to move offshore, i.e. to use space and good wind speeds on the open sea for large scale electricity generation. Offshore wind power, however, is not just technologically challenging but also a capital intensive and risky business that requires particular financial and organizational resources not all potential investors might have. We therefore address the question, what impact offshore wind power may have on ownership and organizational structures in the wind power sector. We compare on- and offshore wind park ownership in Denmark, the UK and Germany. The analysis shows that offshore wind power in all three countries is dominated by large firms, many of which are from the electricity sector. In Denmark and the UK, also investors from the gas and oil industry play an important role in the offshore wind business. This development represents a major shift for countries such as Germany and Denmark, in which the wind power sector has grown and matured on the basis of investments by individuals, farmers, cooperatives and independent project developers. The structural changes by which offshore wind power is accompanied have consequences for turbine manufacturers, project developers, investors, associations and policy makers in the field.

Organic acids are part of assimilable organic carbon (AOC) formed from natural organic matter (NOM) during ozonation for drinking water production. To elucidate the formation of organic acids, phenol as surrogate compound for NOM was ozonated while suppressing reactions of <SUP><B>·</B></SUP>OH radicals by addition of tert-butanol. Batch experiments show benzoquinone (40 and 18%), catechol (33 and 1%), cis,cis-muconic acid (6 and 3%), and hydroquinone (2 and 7%) to be the most abundant primary products at pH 7 and 3, respectively. The tertiary product oxalic acid was obtained in similar yields from phenol ozonation (0.8%) as during ozonation of lake water (1.6%). Together with other low molecular weight organic acids it was formed upon small ozone exposures, as was shown by time-dependent experiments in time ranges of 0.4-23 and 0.07-1.0 seconds for pH 3 and 7.25, respectively.

The extensive nuclear bomb testing of the fifties and sixties and the final tests in the seventies caused a strong <SUP>36</SUP>Cl peak that has been observed in ice cores world-wide. The measured <SUP>36</SUP>Cl deposition fluxes in eight ice cores (Dye3, Fiescherhorn, Grenzgletscher, Guliya, Huascarán, North GRIP, Inylchek (Tien Shan) and Berkner Island) were compared with an ECHAM5-HAM general circulation model simulation (1952–1972). We find a good agreement between the measured and the modeled <SUP>36</SUP>Cl fluxes assuming that the bomb test produced global <SUP>36</SUP>Cl input was ~80 kg. The model simulation indicates that the fallout of the bomb test produced <SUP>36</SUP>Cl is largest in the subtropics and mid-latitudes due to the strong stratosphere-troposphere exchange. In Greenland the <SUP>36</SUP>Cl bomb signal is quite large due to the relatively high precipitation rate. In Antarctica the <SUP>36</SUP>Cl bomb peak is small but is visible even in the driest areas. The model suggests that the large bomb tests in the Northern Hemisphere are visible around the globe but the later (end of sixties and early seventies) smaller tests in the Southern Hemisphere are much less visible in the Northern Hemisphere. The question of how rapidly and to what extent the bomb produced <SUP>36</SUP>Cl is mixed between the hemispheres depends on the season of the bomb test. The model results give an estimate of the amplitude of the bomb peak around the globe.

This article introduces an approach to tailoring behavior-change campaigns to target populations using the example of solid waste reduction in Santiago de Cuba. Tailoring is performed in the following steps: (1) Psychological constructs are selected to detect problems in performing the target behavior, and data are gathered on these constructs. (2) Cluster analyses are performed on these data to identify different psychological types and their distribution in the population. (3) Intervention techniques are assigned according to the spatial and quantitative distribution and the characteristics of these types. Results of the cluster analyses are presented for three different behaviors that can reduce the amount of deposited solid waste (recycling, composting, reuse) on the basis of the four psychological constructs of instrumental and affective attitude, difficulty, and social pressure. The tailoring of interventions could be used to design environmental campaigns more efficiently.

Temperature reconstructions for recent centuries are the basis of estimations of the natural variability in the climate system before and during the onset of anthropogenic perturbation. Here we present, for the first time, an independent and physically based reconstruction of mean annual temperature over the past half millennium obtained from groundwater in France. The reconstructed noble gas temperature (NGT) record suggests cooler than present climate conditions throughout the 16th–19th centuries. Periods of warming occur in the 17th–18th and 20th century, while cooling is reconstructed in the 19th century. A noticeable coincidence with other temperature records is demonstrated. Deuterium excess varies in parallel with the NGT, and indicates variation in the seasonality of the aquifer recharge; whereas high excess air in groundwater indicates periods with high oscillations of the water table.

<I>Background, aim and scope</I> After the discovery of chloroform in drinking water, an extensive amount of work has been dedicated to the factors influencing the formation of halogenated disinfections by-products (DBPs). The disinfection practice can vary significantly from one country to another. Whereas no disinfectant is added to many water supplies in Switzerland or no disinfectant residual is maintained in the distribution system, high disinfectant doses are applied together with high residual concentrations in the distribution system in other countries such as the USA or some southern European countries and Romania. In the present study, several treatment plants in the Somes river basin in Romania were investigated with regard to chlorine practice and DBP formation (trihalomethanes (THMs)). Laboratory kinetic studies were also performed to investigate whether there is a relationship between raw water dissolved organic matter, residual chlorine, water temperature and THM formation.<BR/><I>Materials and methods</I> Drinking water samples were collected from different sampling points in the water treatment plant (WTP) from Gilau and the corresponding distribution system in Cluj-Napoca and also from Beclean, Dej and Jibou WTPs. The water samples were collected once a month from July 2006 to November 2007 and stored in 40-mL vials closed with Teflon lined screw caps. Water samples were preserved at 4°C until analysis after sodium thiosulfate (Na<SUB>2</SUB>S<SUB>2</SUB>O<SUB>3</SUB>) had been added to quench residual chlorine. All samples were analysed for THMs using headspace GC-ECD between 1 and 7 days after sampling. The sample (10 mL) was filled into 20-mL headspace vials and closed with a Teflon-lined screw cap. Thereafter, the samples were equilibrated in an oven at 60°C for 45 min. The headspace (1 mL) was then injected into the GC (Cyanopropylphenyl Polysiloxane column, 30 m × 53 mm, 3 μm film thickness, Thermo Finnigan, USA). The MDLs for THMs were determined from the standard deviation of eight standards at 1 μg/L. The MDLs for CHCl<SUB>3</SUB>, CHBrCl<SUB>2</SUB>, CHBr<SUB>2</SUB>Cl and CHBr<SUB>3</SUB> were 0.3, 0.2, 0.3 and 0.6 μg/L, respectively. All kinetic laboratory studies were carried out only with water from the WTP Gilau. The experiments were conducted under two conditions: baseline conditions (pH 7, 21°C, 2.5 mg/L Cl<SUB>2</SUB>) to gain information about the change of the organic matter in the raw water and seasonally variable conditions to simulate the actual process at the treatment plant and the distribution system.<BR/><I>Results and discussion</I> This study shows that the current chlorination practice in the investigated plants complies with the THM drinking water standards of the EU. The THM concentrations in all samples taken in the four treatment plants and distributions systems were below the EU drinking water standard for TTHMs of 100 μg/L. Due to the low bromide levels in the raw waters, the main THM formed in the investigated plants is chloroform. It could also be seen that the THM levels were typically lower in water supplies with groundwater as their water resource. In one plant (Dej) with a pre-ozonation step, a significantly lower (50%) THM formation during post-chlorination was observed. Laboratory chlorination experiments revealed a good correlation between chloroform formation and the consumed chlorine dose. Also, these experiments allowed a semi-quantative prediction of the chloroform formation in the distribution system of Cluj-Napoca.<BR/><I>Conclusions</I> CHCl<SUB>3</SUB> was the most important trihalomethane species observed after the chlorination of water in all of the sampled months. However, TTHM concentrations did not exceed the maximum permissible value of 100 μg/L (EU). The THM formation rates in the distribution system of Cluj-Napoca have a high seasonal variability. Kinetic laboratory experiments could be used to predict chloroform formation in the Cluj-Napoca distribution system. Furthermore, an empirical model allowed an estimation of the chloroform formation in the Gilau water treatment plant.

TEMPEST is a new interactive simulation program for the estimation of the wastewater temperature in sewers. Intuitive graphical user interfaces assist the user in managing data, performing calculations and plotting results. The program calculates the dynamics and longitudinal spatial profiles of the wastewater temperature in sewer lines. Interactions between wastewater, sewer air and surrounding soil are modeled in TEMPEST by mass balance equations, rate expressions found in the literature and a new empirical model of the airflow in the sewer. TEMPEST was developed as a tool which can be applied in practice, i.e., it requires as few input data as possible. These data include the upstream wastewater discharge and temperature, geometric and hydraulic parameters of the sewer, material properties of the sewer pipe and surrounding soil, ambient conditions, and estimates of the capacity of openings for air exchange between sewer and environment. Based on a case study it is shown how TEMPEST can be applied to estimate the decrease of the downstream wastewater temperature caused by heat recovery from the sewer. Because the efficiency of nitrification strongly depends on the wastewater temperature, this application is of practical relevance for situations in which the sewer ends at a nitrifying wastewater treatment plant.

Lake Kivu is one of the large African Rift lakes situated between the Democratic Republic of the Congo and Rwanda. In its permanently stratified hypolimnion, unusually high methane concentrations have increased further in recent decades. Because methanogenesis is, in part, dependent on supply of organic material from the photic zone, it is necessary to quantify upward nutrient fluxes from the saline, nutrient-rich deep waters. These upward fluxes are mainly driven by advection caused by subaquatic springs. Biogenic calcite precipitation drives surface-water depletion and deep-water enrichment of Ca²⁺, Sr²⁺, and Ba²⁺. Methane is mainly oxidized aerobically at the redox interface at 60 m, with a small contribution of anaerobic methane oxidation. A subaquatic spring that sustains the major chemocline at 250 m depth was depleted of N, P, and CH₄, and concentrations of major ions were slightly lower than in the lake water of the same depth. Enrichment of the deep waters with nutrients and CH₄ are driven by mineralization of settling organic material, whereas SiO₂ is influenced by uptake and mineralization of diatoms and inputs through subaquatic springs. Dissolved inorganic phosphorus and Si fluxes supplied by internal loading through upwelling were found to be lower than the estimations for Lakes Malawi and Tanganyika. In contrast, N flux was within the lower range for Lake Malawi, whereas it was assumed to be totally lost by denitrification in Lake Tanganyika. In Lake Kivu, nutrient uptake by primary production is three times higher than nutrient upward fluxes.

Colloids, such as submicrometre mineral particles or bacterial cells, can act as carriers enhancing the mobility of poorly soluble contaminants in subsurface environments<SUP>1,2</SUP>. In sulphate-reducing soils and sediments, metal sulphide precipitation has been proposed<SUP>3-6</SUP> to generate contaminant-bearing sulphide colloids, which could transport contaminants traditionally thought to be immobilized by metal sulphide formation<SUP>7</SUP>. However, direct evidence for such a process is lacking. Here, we report the composition and morphology of pore-water colloids formed in contaminated floodplain soil when flooded with synthetic river water over a four-week period. We show that, on flooding, bacteria dispersed in the pore water mobilize copper by inducing biomineralization of metallic copper(0). We suggest that copper(0) crystals form by disproportionation of copper(I), which is released by copper-stressed bacteria to maintain copper homeostasis<SUP>8,9</SUP>. Sulphate reduction, which started on the fourth day of flooding, resulted in the mobilization of cadmium and lead, which were partitioned to copper-rich sulphide colloids showing two types of morphology: bacterium-associated 50–150-nm-diameter hollow particles formed through copper(0) transformation, and dispersed <50 nm nanoparticles, probably formed through homogeneous precipitation. The slow deposition of both types of sulphide colloid ensured elevated contaminant concentrations in the pore water for weeks. Our findings imply that colloid formation can enhance contaminant release from periodically sulphate-reducing soils and sediments, potentially polluting surface- and groundwaters.

We determined the speciation of Zn in 49 field soils differing widely in pH (4.1–7.7) and total Zn content (251–30,090 mg/kg) by using extended X-ray absorption fine structure (EXAFS) spectroscopy. All soils had been contaminated since several decades by inputs of aqueous Zn with runoff-water from galvanized power line towers. Pedogenic Zn species identified by EXAFS spectroscopy included Zn in hydroxy-interlayered minerals (Zn-HIM), Zn-rich phyllosilicates, Zn-layered double hydroxide (Zn-LDH), hydrozincite, and octahedrally and tetrahedrally coordinated sorbed or complexed Zn. Zn-HIM was only observed in (mostly acidic) soils containing less than 2000 mg/kg of Zn, reflecting the high affinity but limited sorption capacity of HIM. Zn-bearing precipitates, such as Zn-LDH and Zn-rich trioctahedral phyllosilicates, became more dominant with increasing pH and increasing total Zn content relative to available adsorption sites. Zn-LDH was the most abundant Zn-precipitate and was detected in soils with pH > 5.2. Zn-rich phyllosilicates were detected even at lower soil pH, but were generally less abundant than Zn-LDH. Hydrozincite was only identified in two calcareous soils with extremely high Zn contents. In addition to Zn-LDH, large amounts of Zn in highly contaminated soils were mainly accumulated as sorbed/complexed Zn in tetrahedral coordination. Soils grouped according to their Zn speciation inferred from EXAFS spectroscopy mainly differed with respect to soil pH and total Zn content. Clear differences were observed with respect to Zn fractionation by sequential extraction: From Zn-HIM containing soils, most of the total Zn was recovered in the exchangeable and the most recalcitrant fractions. In contrast, from soils containing the highest percentage of Zn-precipitates, Zn was mainly extracted in intermediate extraction steps. The results of this study demonstrate that soil pH and Zn contamination level relative to available adsorption sites are the most important factors controlling the formation of pedogenic Zn-species in aerobic soils and, consequently, Zn fractionation by sequential extraction.

The electrochemical behaviour of ammonia (NH<SUB>4</SUB><SUP>+</SUP>/NH<SUB>3</SUB>) in sodium perchlorate at pH 9 has been investigated on electrochemically grown anodic iridium oxide film (AIROF) electrode. In base electrolyte at pH 9, the Ir(IV)/Ir(III) surface redox couple exhibits unusually large separation of the oxidation/reduction peaks (Δ<I>E</I><SUB>p</SUB>~ 750 mV) due to the local pH changes within the oxide film. These local pH changes are induced by protons released/consumed during the Ir(IV)/Ir(III) redox activity. As a consequence, the local pH within AIROF changed up to 10 units during potential cycling. The presence of ammonia at pH 9 prevents these local pH changes because NH<SUB>4</SUB><SUP>+</SUP>/NH<SUB>3</SUB> buffer the solution inside the electrode. As a consequence, Δ<I>E</I><SUB>p</SUB> of Ir(IV)/Ir(III) was reduced to 100 mV. It has been shown further that ammonia oxidation is mediated by Ir(V), resulting in the appearance of anodic peaks in forward and backward scans.

The degassing of volcanic Lake Nyos (Cameroon) provides the opportunity to study the strong isotopic variation of dissolved Fe(II) in a well constrained redox cycle and to identify the governing processes by reaction-transport modeling. Two depth profiles sampled in the lake in March 2004 and 2005 reveal an increase in iron concentrations and <I>δ</I><SUP>57</SUP>Fe from around 1 mg L<SUP>−1</SUP> and −1.88‰ at 55 m depth up to 344 mg L<SUP>−1</SUP> and +0.83‰ at the bottom of the lake, respectively. A steep increase in <I>δ</I><SUP>57</SUP>Fe was observed across the oxic–anoxic boundary. As many biological and geochemical processes are known to fractionate Fe isotopes, we used a calibrated reaction-transport model to disentangle the processes governing the Fe cycle. The model combines the isotopic signatures of dissolved Fe(II) and settling Fe(III) particles with the concentration profiles and settling fluxes of the Fe particles in the lake. We show that the strong shift in <I>δ</I><SUP>57</SUP>Fe is caused by isotopic fractionation via dissimilatory Fe reduction across the oxic–anoxic boundary of Lake Nyos. The shift towards more positive values below the oxic–anoxic interface could be attributed to vertical mixing of a heavier component from the bottom of the lake.

The oxidation of iodide by synthetic birnessite (δ-MnO<SUB>2</SUB>) was studied in perchlorate media in the pH range 4–8. Iodine (I<SUB>2</SUB>) was detected as an oxidation product that was subsequently further oxidized to iodate (IO<SUB>3</SUB><SUP>–</SUP>). The third order rate constants, second order on iodide and first order on manganese oxide, determined by extraction of iodine in benzene decreased with increasing pH (6.3–7.5) from 1790 to 3.1 M<SUP>−2</SUP> s<SUP>−1</SUP>. Both iodine and iodate were found to adsorb significantly on birnessite with an adsorption capacity of 12.7 μM/g for iodate at pH 5.7. The rate of iodine oxidation by birnessite decreased with increasing ionic strength, which resulted in a lower rate of iodate formation. The production of iodine in iodide-containing waters in contact with manganese oxides may result in the formation of undesired iodinated organic compounds (taste and odor, toxicity) in natural and technical systems. The probability of the formation of such compounds is highest in the pH range 5–7.5. For pH <5 iodine is quickly oxidized to iodate, a non-toxic and stable sink for iodine. At pH >7.5, iodide is not oxidized to a significant extent.

High levels of naturally occurring arsenic are found in the shallow reducing aquifers of West Bengal, Bangladesh, and other areas of Southeast Asia. These aquifers are used extensively for drinking water and irrigation by the local population. Mechanisms for its release are unclear, although increasing evidence points to a microbial control. The type of organic matter present is of vital importance because it has a direct impact on the rate of microbial activity and on the amount of arsenic released into the ground water. The discovery of naturally occurring hydrocarbons in an arsenic-rich aquifer from West Bengal provides a source of potential electron donors for this process. Using microcosm-based techniques, seven sediments from a site containing naturally occurring hydrocarbons in West Bengal were incubated with synthetic ground water for 28 d under anaerobic conditions without the addition of an external electron donor. Arsenic release and Fe(III) reduction appeared to be microbially mediated, with variable rates of arsenic mobilization in comparison to Fe(III) reduction, suggesting that multiple processes are involved. All sediments showed a preferential loss of petroleum-sourced n-alkanes over terrestrially sourced sedimentary hydrocarbons n-alkanes during the incubation, implying that the use of petroleum-sourced n-alkanes could support, directly or indirectly, microbial Fe(III) reduction. Samples undergoing maximal release of As(III) contained a significant population of <em>Sulfurospirillum</em> sp., a known As(V)-reducing bacterium, providing the first evidence that such organisms may mediate arsenic release from West Bengali aquifers.

The Red Queen coevolutionary hypothesis predicts that parasites drive oscillations in host genotype frequencies due to frequency-dependent selection where common hosts are at disadvantage. However, examples of this phenomenon in natural populations are scarce. To examine if the Red Queen theory operates in the wild, we studied the genetic structure of populations of the crustacean waterflea (<I>Daphnia</I>), in relation to their infection levels, for which we collected multiple samples from a variety of lakes. The most common clone in a given population was often underinfected. This advantage, however, did not remain stable over time. Instead, the most common clone decreased in frequency over subsequent generations, indicating that parasites can track common clones. Such decreases were not observed in uninfected populations. Moreover, host clonal evenness was higher across the set of infected lakes compared to uninfected lakes; suggesting that any common clone is selected against when parasites are present. These results strongly suggest that Red Queen dynamics do operate in the wild.

Membrane bioreactor (MBR) technology is an interesting option for single-house wastewater treatment or small communities. Because typically a very high effluent quality is achieved with respect to pathogens, suspended solids, organics and nitrogen, the permeate is well suited for reuse. Little is known about the fate of micropollutants in such small systems. The differences between centralized and decentralized biological wastewater treatment with respect to micropollutants are manifold: besides the operational parameters like hydraulic and sludge retention time, the main difference is in the load variation. While the influent load is expected to be more or less constant in large catchments, it varies strongly in small MBRs due to irregular consumption (e.g. of medication by individuals). Concentrations of micropollutants are higher by a factor 50–1000 than in centralized treatment. It is also unknown how reliable degradation of micropollutants is in case of irregular exposure.<br/> In this study, two experiments were conducted in a small MBR treating the wastewater of a three-person household. During normal operation of the treatment plant, 25 pharmaceuticals (antibiotics, antiphlogistics, lipid regulators, iodinated contrast media and hormones) that had not been used by members of the household were added in concentrations typical for municipal wastewater. The removal of most substances was in the same range as for centralized wastewater treatment. It was shown that biological transformation was the main elimination process while adsorption to the activated sludge was negligible for most substances due to the low sludge production at high sludge retention time. No appreciable lag for inducing biological degradation was observed. The high hydraulic and sludge residence time had a positive effect on the elimination of slowly degradable substances, but this was partly compensated by the lower biological activity.<br/> An experiment with antibiotics concentrations typical for decentralized treatment (between 500 and 1000 μg l<SUP>−1</SUP>; sulfamethoxazole, sulfapyridine, trimethoprim, clarithromycin, roxithromycin) did not show an inhibitory effect on either nitrification or denitrification.

Micropollutants represent one of today’s main concerns for surface water management. One of the major sources of micropollutants to the environment is linked with the discharge of pharmaceutical residues by the population. Although some technologies exist today to deal with these kinds of discharges, source-control strategies constitute a very interesting solution and are illustrated in this paper. We focus here on the NoMix technology, an innovative at-source solution to separate liquid and solid wastes. The NoMix new technology proposes to separate urine directly at the source. Urine (1.5 litre/inhabitant per day)constitutes less than 1% of the volume processed in waste water treatment plants. However, it contains the most important part of nutrients (80% nitrogen, 50% phosphorus) and a major part of the pharmaceuticals released by the human metabolism (64%, ± 27%). A separate collection and treatment of urine offers thus an interesting potential for micropollutants removal. The NoMix concept has been studied for many years by Eawag (Swiss Federal Institute of Aquatic Science and Technology) within the framework of an inter- and trans-disciplinary project entitled “Novaquatis”.The results of this project show that the NoMix technology would be significant to reduce at-source micropollutants. Moreover, it allows the nutrients produced in urban areas to be recycled, once treated, as fertilisers for agriculture. This article briefly presents the concept of at-source control, as wellas the main results of the Novaquatis project.

Lake Estanya is a small (19 ha), freshwater to brackish, monomictic lake formed by the coalescence of two karstic sinkholes with maximum water depths of 12 and 20 m, located in the Pre-Pyrenean Ranges (North-eastern Spain). The lake is hydrologically closed and the water balance is controlled mostly by groundwater input and evaporation. Three main modern depositional sub-environments can be recognized as: (i) a carbonate-producing 'littoral platform'; (ii) a steep 'talus' dominated by reworking of littoral sediments and mass-wasting processes; and (iii) an 'offshore, distal area', seasonally affected by anoxia with fine-grained, clastic sediment deposition. A seismic survey identified up to 15 m thick sedimentary infill comprising: (i) a 'basal unit', seismically transparent and restricted to the depocentres of both sub-basins; (ii) an 'intermediate unit' characterized by continuous high-amplitude reflections; and (iii) an 'upper unit' with strong parallel reflectors. Several mass-wasting deposits occur in both sub-basins. Five sediment cores were analysed using sedimentological, microscopic, geochemical and physical techniques. The chronological model for the sediment sequence is based on 17 accelerator mass spectrometry <SUP>14</SUP>C dates. Five depositional environments were characterized by their respective sedimentary facies associations. The depositional history of Lake Estanya during the last <I>ca</I> 21 kyr comprises five stages: (i) a brackish, shallow, calcite-producing lake during full glacial times (21 to 17·3 kyr bp); (ii) a saline, permanent, relatively deep lake during the late glacial (17·3 to 11·6 kyr bp); (iii) an ephemeral, saline lake and saline mudflat complex during the transition to the Holocene (11·6 to 9·4 kyr bp); (iv) a saline lake with gypsum-rich, laminated facies and abundant microbial mats punctuated by periods of more frequent flooding episodes and clastic-dominated deposition during the Holocene (9·4 to 0·8 kyr bp); and (v) a deep, freshwater to brackish lake with high clastic input during the last 800 years. Climate-driven hydrological fluctuations are the main internal control in the evolution of the lake during the last 21 kyr, affecting water salinity, lake-level changes and water stratification. However, external factors, such as karstic processes, clastic input and the occurrence of mass-flows, are also significant. The facies model defined for Lake Estanya is an essential tool for deciphering the main factors influencing lake deposition and to evaluate the most suitable proxies for lake level, climate and environmental reconstructions, and it is applicable to modern karstic lakes and to ancient lacustrine formations.

The occurrence of algal taste and odor (T&O) compounds was investigated in three Swiss lakes which exhibit different nutrient levels from eutrophic to oligotrophic (Lake Greifensee, Lake Zurich and Lake Lucerne). Apart from dissolved T&O compounds, the study also encompassed particle-bound compounds, i.e., compounds that can be released from damaged algal cells during drinking water treatment. A combined instrumental (SPME-GC-MS) and sensory method was applied that allowed to detect and quantify T&O compounds in natural waters in the sub ppt to low ppt-range.<BR/> In addition to the prominent T&O compounds geosmin and 2-methyl-isoborneol (MIB), four other T&O compounds could be detected in the lake waters, though all at relatively low concentrations (maximum concentrations of geosmin 19 ng L<SUP>–1</SUP>, MIB 3 ng L<SUP>–1</SUP>, β-ionone 27 ng L<SUP>–1</SUP>, β-cyclocitral 7 ng L<SUP>–1</SUP>, 2-isobutyl-3-methoxypyrazine 2 ng L<SUP>–1</SUP>, 2-isopropyl-3-methoxypyrazine 16 ng L<SUP>–1</SUP>). The concentration peaks typically occurred in the epilimnion during summer concurrent with a high phytoplankton biomass. Consistently, the concentration levels for most of the compounds varied substantially between the three lakes and generally decreased in the order eutrophic Lake Greifensee > mesotrophic Lake Zurich > oligotrophic Lake Lucerne. Furthermore, our data revealed that the occurrence of β-ionone was largely influenced by <I>Planktothrix rubescens</I>. This is the first time that a correlation between β-ionone and this cyanobacterium has been reported for natural waters.

Waterbirds are often observed to move between different wintering sites within the same winter—for example, in response to food availability or weather conditions. Within-winter movements may contribute to the spreading of diseases, such as avian influenza, outside the actual migration period. The Common Pochard <I>Aythya ferina</I> seems to be particularly sensitive to infection with the highly pathogenic avian influenza virus H5N1 and, consequently, could play an important role as vectors for the disease. We describe here the within-winter movements of Pochards in Europe in relation to topography, climate, sex and age. We analysed data provided by the Euring data bank on 201 individuals for which records from different locations from the same winter (December–February) were available. The distances and directions moved within the winter varied markedly between regions, which could be ascribed to the differing topography (coast lines, Alps). We found no significant differences in terms of distances and directions moved between the sexes and only weak indications of differences between the age classes. In Switzerland, juveniles moved in more westerly directions than adults. During relatively mild winters, winter harshness had no effect on the distances travelled, but in cold winters, a positive relationship was observed, a pattern possibly triggered by the freezing of lakes. Winter harshness did not influence the directions of the movement. About 41% (83/201) of the Pochards that were recovered at least 1 km from the ringing site had moved more than 200 km. A substantial number of birds moved between central/southern Europe and the north-western coast of mainland Europe, and between the north-western coast of mainland Europe and Great Britain, whereas no direct exchange between Great Britain and central/southern Europe was observed. Within-winter movements of Pochards seem to be a common phenomenon in all years and possibly occur as a response to the depletion of food resources. This high tendency to move could potentially contribute to the spread of bird-transmitted diseases outside the actual migration period.

This review deals with the complex sex determining system of Nile tilapia, <I>Oreochromis niloticus</I>, governed by the interactions between a genetic determination and the influence of temperature, shown in both domestic and wild populations. Naturally sex reversed individuals are strongly suggested in two wild populations. This can be due to the masculinising temperatures which some fry encounter during their sex differentiation period when they colonise shallow waters, and/or to the influence of minor genetic factors. Differences regarding a) thermal responsiveness of sex ratios between and within Nile tilapia populations, b) maternal and paternal effects on temperature dependent sex ratios and c) nearly identical results in offspring of repeated matings, demonstrate that thermosensitivity is under genetic control. Selection experiments to increase the thermosensitivity revealed high responses in the high and low sensitive lines. The high-line showed ~ 90% males after 2 generations of selection whereas the weakly sensitive line had 54% males. This is the first evidence that a surplus of males in temperature treated groups can be selected as a quantitative trait. Expression profiles of several genes (<I>Cyp19a</I>, <I>Foxl2</I>, <I>Amh</I>, <I>Sox9a</I>,<I>b</I>) from the gonad and brain were analysed to define temperature action on the sex determining/differentiating cascade in tilapia. The coexistence of GSD and TSD is discussed.