Die nähere Betrachtung der bisher bekannten, durch Aquädukte aus den Wadis gespiesene Wasserversorgung des herodianischen Palast- und Festungswerkes Masada zeigt, dass diese allein der Aufgabe nicht hätte gerecht werden können. Zudem muss schon aus Sicherheitsgründen bei einer Belagerung eine weitere, vom Belagerer nicht störbare Wasserversorgung bestanden haben. <BR/> Eine zusätzliche Wassergewinnung konnte nur mittels Taubrunnen erfolgen. Die Funktionsweise von Taubrunnen wird dargelegt und die bisher auf Masada entdeckten Taubrunnen beschrieben. Nur durch den Betrieb von solchen Wasserspendern war eine genügende Wasserversorgung für Masada gewährleistet. <BR/> Durch erneute Inbetriebnahme von Taubrunnen wäre es möglich, das 7 ha umfassende Hochplateau wieder fruchtbar zu gestalten. Damit käme ein während 2000 Jahren geheimgehaltenes System der Wassergewinnung für Masada wieder in Funktion.

Auf dem Wäschereisektor besteht zurzeit eine deutliche Tendenz zur Erstellung neuer Grosswäschereien unter Einsatz von Durchlaufautomaten. Die vorliegenden Projekte und die bereits erstellten Anlagen sind auch mit Bezug auf die Produktion ähnlich konzipiert. Es lassen sich daher gemeinsame Kriterien aufstellen. In Ergänzung zu den nachstehend aufgeführten produktionstechnischen Merkmalen werden anschliessend die bisher bekannten Angaben über die Abwasserfrachten und den Wasser- und Waschmittelverbrauch zusammengestellt und mit den Ergebnissen aus früheren Untersuchungen an Wäschereiabwässern und den Betriebsdaten anderer Anlagetypen verglichen.

Lake Brienz is a deep, longitudinal sedimentation-trough with two main tributaries on both ends of the basin. 205 surface samples of the entirely clastic lake sediments have been investigated. Distribution of heavy minerals, sand- and carbonate-content show the exclusive influence of the main rivers - Aare and Lütschine - on hte formation of the surface sediments. Turbitidy currents as well as undercurrents are responsible for transport and deposition of sediments in lake.

The study of vertical mixing in Lake Tahoe by temperature and oxygen measurements is limited to the top layer of the lake, since vertical gradients are extremely small at greater depth. Below 200 m the temperature gradient is about -1.6 ✕ 10^-4 °C m^-1, with little or no seasonal variation. A tritium profile was taken at a midlake station in 1973 together with samples for measurements on lake chemistry. Oxygen, nitrate, total inorganic carbon, and pH showed the effects of photosynthetic activity to a depth of about 80 m, well below the thermocline; average planktonic composition was calculated from these data. Silicate and carbonate alkalinity profiles were essentially uniform, showing that biological removal is negligible in comparison to the rate of vertical mixing.<br/> Essentially no variation in tritium concentration with depth was observed. Tritium measurements and input estimates in Crater Lake were used to calculate tritium concentration in Lake Tahoe between 1954 and 1973 and to estimate a ratio in tritium input of 32% precipitation to 68% vapor exchange. The tritium profile gives strong evidence for at least occasional complete mixing of Lake Tahoe. The last complete mixing may have occurred in March 1973 and at least one other such event took place between 1964 and 1968.

An attempt is made to interpret some aspects of the chemistry of manganese in natural waters on the basis of 1) the kinetics of O₂-oxidation of Mn (II) under sterile conditions and in the presence of Mn (II) oxidizing microorganisms; 2) the nature of oxidized Mn-phases; 3) the adsorption of metal ions on oxide hydroxides of Mn (III), (IV); and 4) information on the transformation of manganese in Swiss lakes.

Effects on inland waters of the discharge of chemicals responsible for eutrophication and organic pollution by degradable and refractory compounds are reviewed. The high ecological sensitivity of aquatic systems to chemical changes is substantiated. The predominant problem of the release of a large number of organic chemicals with very slow or even unproven degradability is indicated. Components of a diversified policy to control the escape of harmful chemicals into the environment are discussed.

The amphoteric properties of hydrous γ-Al₂O₃ and the distribution of earth alkaline cations in the oxide-electrolyte interface was evaluated from alkalimetric and acidimetric titration curves of aqueous dispersions. In NaCl electrolytes (25°C), pH of zero point of charge is pH_zpc = 8.5; acid-base properties can be characterized in terms of a heterogeneous two-protic acid with intrinsic acidity constants p<I>K</I>_int¹ = 7.9 and p<I>K</I>_int² = 9.1.<br/> The extent of adsorption of Ca²⁺ and other earth alkaline cations on hydrous γ-Al₂O₃ increases with increasing pH; finite adsorption is observed at pH_zpc and at pH values slightly lower than pH_zpc. Evaluation of adsorption measurements and alkalimetric titration curves indicates that the adsorption of M²⁺ can be described by: AlOH + M²⁺ ⇄ AlOM⁺ + H⁺. Operational association constants for this equilibrium were determined; the extent of adsorption increases in the series Mg²⁺ > Ca²⁺ > Sr²⁺ > Ba²⁺. In the pH-range above pH_zpc, these ions, upon being adsorbed may reverse the surface charge of the oxide suspension.

The sea-air interface is probably the most poorly understood of the three boundaries separating the system sea-air-land. However, the chemistry of the sea-air interface is receiving increasing attention as its role in environmental problems becomes more apparent. Perhaps in no other region of the environment do microscopic physicochemical and hydrodynamic processes so profoundly affect large-scale geophysical phenomena as they do in the transfer of material from sea to air. The solutions to many problems in air pollution and water pollution as well as a complete assessment of the geochemical cycles of many elements are critically dependent on a better understanding of sea-surface phenomena.

Adsorption isotherms in 0.01 M NaCl solutions at 25°C have been measured over the phosphate concentration range 2 × 10^-7-2 × 10^-4 <I>M</I> and the pH range 2-12. The Langmuir isotherm is approximately obeyed, but there appear to be a few sites of substantially higher energy which are occupied more readily at the lowest concentrations. Curves of total phosphate removed by alumina and kaolinite from a constant volume of solution, as a function of pH, go through a maximum at approximately pH = 4 for both. The effect of some cations (Ca²⁺ < La³⁺ < Purifloc C-31 cationic polyelectrolyte) is to increase phosphate adsorption for pH > 4. The effect of some anions (humic acid ≈ succinate ≈ polystyrenesulfonate) is to decrease phosphate adsorption for pH < 6. Complexing agents (F^- ≤ tartrate < oxalate < EDTA < citrate) with a high affinity for Al had much larger and quite complex effects, and also decreased phosphate adsorption over a wider range (pH < 8). Similar additions of arginine, methylamine, glycine, acetate, silicate, alkylbenzene sulfonate, HCO₃^-, Mg²⁺, and Co²⁺ had little or no effect.

The reaction of aqueous phosphate (∼3 × 10^-4M) with alumina and kaolinite shows a rapid (12-24 hr) adsorption step followed by a slow process, obeying a first-order rate law, which extends over the next 60 days and probably involves nucleation and growth of a hexagonal AlPO₄ phase. For kaolinite with 10.7 m²/g surface area, solids concentration 7.5 g/l, pH = 4.6, as well as for α-Al₂O₃ with surface area 10 m²/g, solids concentration 2.5 g/l, and pH = 4.3, the first-order rate constant at 50°C is 0.022 day^-1. Increasing temperature increases the rate, with an activation energy of 2.4 Kcal/mol. Addition of fluoride ion (10^-4M) decreases the amount of phosphate initially adsorbed but does not affect the first-order rate. The rate constant increases proportionally to the solid surface available, and decreases with increasing pH to essentially zero at pH ≥ 7. Successive addition of phosphate aliquots to the same sample of solid uses up the sites available for the rapid initial step but does not strongly influence the rate of the slow step.

We measured the concentrations of natural <SUP>222</SUP>Rn (half-life 3.8 days) in groundwater at three sites in Switzerland; here groundwater is recharged mainly by river water. Upon infiltration and movement in the ground, the radon concentration in the water increases by more than two orders of magnitude to reach a steady state. This increase was found at two of the three sites. At the site of main interest, we used the ingrowth of radon between the river and nearby observation wells to estimate groundwater residence times of up to about four half lives. We assumed that the ingrowth of radon can be described by the growth law of radioactivity, that the progenitors of radon (<SUP>226</SUP>Ra, <SUP>238</SUP>U) are homogeneously distributed in the aquifer, and that the freshly infiltrated water is not mixed significantly with older groundwater. A linear regression through the data at the site of main interest yielded an average flow velocity of 4.6 m d<SUP>-1</SUP>, which confirms earlier tracer observations. Radon accumulates to higher concentrations, when the top soil layer is frozen or exhibits a high moisture content. During these conditions the radon data cannot be used for dating purposes.

Following the Water Framework Directive (WFD) requirements, we designed a new multimetric index (I<SUB>2</SUB>M<SUB>2</SUB>) for the invertebrate-based ecological assessment of French wadeable streams. This index should be able to identify impaired reaches for 17 anthropogenic pressure categories potentially leading to water quality alteration or habitat degradation. Based on a national database, we defined an iterative procedure to select taxonomy- and trait-based metrics exhibiting the best trade-off between (i) high discrimination efficiency, (ii) low specificity and (iii) high stability in least impaired conditions. The I<SUB>2</SUB>M<SUB>2</SUB>, defined as the best combination of such metrics, has been composed by: (i) Shannon diversity index, (ii) original ASPT score, (iii) the relative abundance of polyvoltine taxa, (iv) the relative abundance of ovoviviparous taxa and (v) taxonomic richness. The I<SUB>2</SUB>M<SUB>2</SUB> was tested against an independent data set. It exhibited good and robust pressure-impact relationship for all the pressure categories, correctly identifying in average 82% of reaches impaired by water quality alterations or habitat degradation. The I<SUB>2</SUB>M<SUB>2</SUB> significantly improved the detection of impaired reaches by at least 17% for nitrogen compounds and up to 35% for organic micropollutants and clogging risk, when compared to the normalized French biotic index (IBGN). The I<SUB>2</SUB>M<SUB>2</SUB> has been proposed for future use in the national biomonitoring of wadeable reaches in the context of the WFD implementation.

Periodically-harvested closures are commonly employed within co-management frameworks to help manage small-scale, multi-species fisheries in the Indo-Pacific. Despite their widespread use, the benefits of periodic harvesting strategies for multi-species fisheries have, to date, been largely untested. We examine catch and effort data from four periodically-harvested reef areas and 55 continuously-fished reefs in Solomon Islands. We test the hypothesis that fishing in periodically-harvested closures would yield: (a) higher catch rates, (b) proportionally more short lived, fast growing, sedentary taxa, and (c) larger finfish and invertebrates, compared to catches from reefs continuously open to fishing. Our study showed that catch rates were significantly higher from periodically-harvested closures for gleaning of invertebrates, but not for line and spear fishing. The family level composition of catches did not vary significantly between open reefs and periodically-harvested closures. Fish captured from periodically-harvested closures were slightly larger, but <I>Trochus niloticus</I> were significantly smaller than those from continuously open reefs. In one case of intense and prolonged harvesting, gleaning catch rates significantly declined, suggesting invertebrate stocks were substantially depleted in the early stages of the open period. Our study suggests periodically-harvested closures can have some short term benefits via increasing harvesting efficiency. However, we did not find evidence that the strategy had substantially benefited multi-species fin-fisheries.

A heterotrophic biofilm (B1) and a mixed autotrophic–heterotrophic biofilm (B2) were developed in an annular reactor and submitted to an erosion test in order to selectively detach top layers from the bottom layers. Densities of the basal layers were 5-fold higher and 3-fold higher than the densities of the entire biofilms B1 and B2, respectively. After extraction, EPS content in B1 biofilm was found higher in the basal layer (95 mg g<SUP>−1</SUP> VSS) compared to the top layer (30 mg g<SUP>−1</SUP> VSS), while B2 biofilm had a higher EPS content in the top layer (303 mg g<SUP>−1</SUP> VSS) compared to the basal layer (135 mg g<SUP>−1</SUP> VSS). Hydrophobic Interaction Chromatography (HIC) indicates that hydrophobic EPS (HEPS) in both biofilms reached 21% of EPS in basal cohesive layers, and remained slightly lower or identical (16–19%) in top detached biofilm layers. Strong interacting HEPS were found in a higher proportion in the mixed autotrophic–heterotrophic B2 which was also more diversified in terms of bacterial populations than the B1 heterotrophic biofilm.<BR/>These results show that HEPS content correlates better with cohesive properties of the biofilm layers than global EPS content and that strong hydrophobic adhesion forces may be related to microbial populations such as the presence of nitrifiers. .

1. The acceptance of reserves as a useful management strategy relies on evidence of their effectiveness in preserving stocks of harvested species and conserving biodiversity. A history of <I>ad hoc</I> decisions in terrestrial and marine protected area planning has meant that many of these areas are contributing inefficiently to conservation goals. The conservation value of existing protected areas should be assessed when planning the placement of additional areas in a reserve network.<BR/>2. This study tested (1) the effectiveness of protection for intertidal molluscs of a marine reserve (Bouddi Marine Extension, NSW, Australia) established in 1971, and (2) the contribution of the protected area to the conservation of regional species, assemblages, and habitats.<BR/>3. The shell length and population density of one harvested (<I>Cellana tramoserica</I>), and three non-harvested species (<I>Bembicium nanum, Morula marginalba, Nerita atramentosa</I>) of intertidal molluscs were examined in the protected area and two reference locations over two seasons.<BR/>4. The heavily collected limpet <I>C. tramoserica</I> was significantly larger in the protected area and was the only species to exhibit a significant difference. No species significantly differed in population density between the protected area and reference locations.<BR/>5. Temporally replicated surveys of macro-molluscs at 21 locations over 75 km of coastline identified that the existing protected area included 50% of species, two of five assemblage types and 19 of 20 intertidal rocky shore habitats surveyed in the study region. Reservation of a further three rocky reefs would protect a large proportion of species (71%), a representative of each assemblage and all habitat types.<BR/>6. Despite originally being selected in the absence of information on regional biodiversity, the protected area is today an effective starting point for expansion to a regional network of intertidal protected areas.

Extended X-ray absorption fine structure (EXAFS) and Mössbauer spectroscopy combined with macroscopic sorption experiments were employed to investigate the sorption mechanism of Fe(II) on an iron-free synthetic montmorillonite (Na-IFM). Batch sorption experiments were performed to measure the Fe(II) uptake on Na-IFM at trace concentrations as a function of pH and as a function of sorbate concentration at pH 6.2 and 6.7 under anoxic conditions (O₂ &lt; 0.1 ppm). A two-site protolysis nonelectrostatic surface complexation and cation exchange sorption model was used to quantitatively describe the uptake of Fe(II) on Na-IFM. Two types of clay surface binding sites were required to model the Fe(II) sorption, the so-called strong (≡S^SOH) and weak (≡S^WOH) sites. EXAFS data show spectroscopic differences between Fe sorbed at low and medium absorber concentrations that were chosen to be characteristic for sorption on strong and weak sites, respectively. Data analysis indicates that Fe is located in the continuity of the octahedral sheet at trans-symmetric sites. Mössbauer spectroscopy measurements confirmed that iron sorbed on the weak edge sites is predominantly present as Fe(II), whereas a significant part of surface-bound Fe(III) was produced on the strong sites (12% vs 37% Fe(III) species to total sorbed Fe).

We investigate the extent to which different forms of community participation explain variation in handpump sustainability using data collected from 200 rural communities in Ghana. Data sources include household surveys, engineering assessments of water points, and interviews with water committees and village leaders. The depth of community members’ involvement in project planning is positively associated with handpump sustainability, whereas the breadth of community participation is not. All else held constant, handpump sustainability is enhanced by household members’ involvement in management-related decisions, but is compromised when households are responsible for technical decisions.

Climate change is clearly discernible in observed climate records in Switzerland. It impacts on natural systems, ecosystems, and economic sectors such as agriculture, tourism, and energy, and it affects Swiss livelihood in various ways. The observed and projected changes call for a response from the political system, which in Switzerland is characterized by federalism and direct democratic instruments. Swiss climate science embraces natural and social sciences and builds on institutionalized links between researchers, public, and private stakeholders. In this article, we review the physical, institutional, and political aspects of climate change in Switzerland. We show how the current state of Swiss climate science and policy developed over the past 20 years in the context of international developments and national responses. Specific to Switzerland is its topographic setting with mountain regions and lowlands on both sides of the Alpine ridge, which makes climate change clearly apparent and for some aspects (tourist sector, hydropower, and extreme events) highly relevant and better perceivable (e.g., retreating glaciers). Not surprisingly the Alpine region is of central interest in Swiss climate change studies.

The increasing use of zinc oxide nanoparticles (nZnO) and their associated environmental occurrence make it necessary to assess their potential effects on aquatic organisms. Upon water contact, nZnO dissolve partially to zinc (Zn(II)). To date it is not yet completely understood, whether effects of nZnO are solely or partly due to dissolved Zn(II). Here we compare potential effects of 0.2, 1 and 5 mg/L nZnO and corresponding concentrations of released Zn(II) by water soluble ZnCl<SUB>2</SUB> to two development stages of zebrafish, embryos and eleuthero-embryos, by analysing expressional changes by RT-qPCR. Another objective was to assess uptake and tissue distribution of Zn(II). Laser ablation-ICP-MS analysis demonstrated that uptake and tissue distribution of Zn(II) were identical for nZnO and ZnCl<SUB>2</SUB> in eleuthero-embryos. Zn(II) was found particularly in the retina/pigment layer of eyes and brain. Both nZnO and dissolved Zn(II) derived from ZnCl<SUB>2</SUB> had similar inhibiting effects on hatching, and they induced similar expressional changes of target genes. At 72 hours post fertilization (hpf), both nZnO and Zn(II) delayed hatching at all doses, and inhibited hatching at 1 and 5 mg/L at 96 hpf. Both nZnO and Zn(II) lead to induction of metallothionein (<I>mt2</I>) in both embryos and eleuthero-embryos at all concentrations. Transcripts of oxidative stress related genes <I>cat</I> and <I>Cu/Zn sod</I> were also altered. Moreover, we show for the first time that nZnO exposure results in transcriptional changes of pro-inflammatory cytokines <I>IL-1β</I> and <I>TNFα</I>. Overall, transcriptional alterations were higher in embryos than eleuthero-embryos. The similarities of the effects lead to the conclusion that effects of nZnO are mainly related to the release of Zn(II).

<I>Objectives:</I> Pharyngeal arches develop in the head and neck regions, and give rise to teeth, oral jaws, the hyoid bone, operculum, gills, and pharyngeal jaws in teleosts. In this study, the expression patterns of genes in the sonic hedgehog (shh), wnt, ectodysplasin A (eda), and bone morphogenetic protein (bmp) pathways were investigated in the pharyngeal arches of <I>Haplochromis piceatus,</I> one of the Lake Victoria cichlids. Furthermore, the role of the shh pathway in pharyngeal arch development in <I>H. piceatus</I> larvae was investigated.<BR/> <I>Methods:</I> The expression patterns of lymphocyte enhancer binding factor 1 (<I>lef1</I>)<I>,</I> ectodysplasin A receptor (<I>edar</I>), <I>shh</I>, patched 1 (<I>ptch1</I>)<I>, bmp4,</I> sp5 transcription factor (<I>sp5</I>), sclerostin domain containing 1a (<I>sostdc1a</I>), and dickkopf 1 (<I>dkk1</I>) were investigated in <I>H. piceatus</I> larvae by <I>in situ</I> hybridization. The role of the shh pathway was investigated through morphological phenotypic characterization after its inhibition.<BR/> <I>Results:</I> We found that <I>lef1</I>, <I>edar, shh, ptch1, bmp4</I>, <I>dkk1</I>, <I>sostdc1a</I>, and <I>sp5</I> were expressed not only in the teeth, but also in the operculum and gill filaments of <I>H piceatus</I> larvae. After blocking the shh pathway using cyclopamine, we observed ectopic <I>shh</I> expression and the disappearance of <I>ptch1</I> expression. After six weeks of cyclopamine treatment, an absence of teeth in the oral upper jaws and a poor outgrowth of premaxilla, operculum, and gill filaments in juvenile <I>H. piceatus</I> were observed.<BR/> <I>Conclusions:</I> These results suggest that the shh pathway is important for the development of pharyngeal arch derivatives such as teeth, premaxilla, operculum, and gill filaments in <I>H. piceatus</I>.

Despite the increasing use of photovoltaics their potential environmental risks are poorly understood. Here, we compared ecotoxicological effects of two thin-film photovoltaics: established copper indium gallium selenide (CIGS) and organic photovoltaic (OPV) cells. Leachates were produced by exposing photovoltaics to UV light, physical damage, and exposure to environmentally relevant model waters, representing mesotrophic lake water, acidic rain, and seawater. CIGS cell leachates contained 583 μg L<SUP>−1</SUP> molybdenum at lake water, whereas at acidic rain and seawater conditions, iron, copper, zinc, molybdenum, cadmium, silver, and tin were present up to 7219 μg L<SUP>−1</SUP>. From OPV, copper (14 μg L<SUP>−1</SUP>), zinc (87 μg L<SUP>−1</SUP>) and silver (78 μg L<SUP>−1</SUP>) leached. Zebrafish embryos were exposed until 120 h post-fertilization to these extracts. CIGS leachates produced under acidic rain, as well as CIGS and OPV leachates produced under seawater conditions resulted in a marked hatching delay and increase in heart edema. Depending on model water and solar cell, transcriptional alterations occurred in genes involved in oxidative stress (<I>cat</I>), hormonal activity (<I>vtg1, ar</I>), metallothionein (<I>mt2</I>), ER stress (<I>bip, chop</I>), and apoptosis (<I>casp9</I>). The effects were dependent on the concentrations of cationic metals in leachates. Addition of ethylenediaminetetraacetic acid protected zebrafish embryos from morphological and molecular effects. Our study suggests that metals leaching from damaged CIGS cells, may pose a potential environmental risk.

Identifying the relative importance of predation and resources in population dynamics has a long tradition in ecology, while interactions between them have been studied less intensively. In order to disentangle the effects of predation by juvenile fish, algal resource availability and their interactive effects on zooplankton population dynamics, we conducted an enclosure experiment where zooplankton were exposed to a gradient of predation of roach (<I>Rutilus rutilus</I>) at different algal concentrations. We show that zooplankton populations collapse under high predation pressure irrespective of resource availability, confirming that juvenile fish are able to severely reduce zooplankton prey when occurring in high densities. At lower predation pressure, however, the effect of predation depended on algal resource availability since high algal resource supply buffered against predation. Hence, we suggest that interactions between mass-hatching of fish, and the strong fluctuations in algal resources in spring have the potential to regulate zooplankton population dynamics. In a broader perspective, increasing spring temperatures due to global warming will most likely affect the timing of these processes and have consequences for the spring and summer zooplankton dynamics.