SOME EFFECTS OF ACIDIFIED WATER ON THE EARLY DEVELOPMENT OF ROACH (Rutilus rutilus L.) AND PERCH (Perca fluviatilis L.)1

ABSTRACT. Fertilized eggs of perch (Perca fluviatilus L.) and roach (Rutilus rutilus L.) were reared at different pH values both in the field and in the laboratory. The results from the laboratory tests revealed that both species showed at least a 50% decrease in their hatching frequencies when reared at pH values below 5.6. At pH values below 4.6 both species studied show an almost complete lack of reproduction. The field studies with eggs from different lakes indicated that there might be an adaptation, manifesting itself as a higher frequency of hatching in water with a composition similar to that of the natural habitat. Field experiments also showed that the roach is more sensitive than perch to low pH values.     

Global sustainability: Toward definition

Sustainability is increasingly viewed as a desired goal of development and environmental management. This term has been used in numerous disciplines and in a variety of contexts, ranging from the concept of maximum sustainable yield in forestry and fisheries management to the vision of a sustainable society with a steady-state economy. The meaning of the term is strongly dependent on the context in which it is applied and on whether its use is based on a social, economic, or ecological perspective, Sustainability may be defined broadly or narrowly, but a useful definition must specify explicitly the context as well as the temporal and spatial scales being considered. Although societies differ in their conceptualizations of sustainability, indefinite human survival on a global scale requires certain basic support systems, which can be maintained only with a healthy environment and a stable human population. A clearer understanding of global sustainability and the development of appropriate indicators of the status of basic support systems would provide a useful framework for policy making.     

The effect of different holding conditions for environmental monitoring with caged rainbow trout (Oncorhynchus mykiss)

Biomarkers in fish can be a useful tool for environmental monitoring of aquatic ecosystems when diffuse pollution is becoming more important and new chemicals are being created continuously. There are, however, a number of drawbacks with this method. Because of environmental variability, health status of wild fish populations may differ between years, leading to unrepresentative results in long term studies. Furthermore, genetic or adaptive differences between populations complicate the interpretation of studies on different sites. The use of farmed fish, placed in cages, can reduce these problems. However, experimental conditions are likely to differ between sites. For practical reasons it may, e.g., be neccesary to use different types of caging. Here, the use of net cages and flow through tanks has been compared for a number of biomarkers. Rainbow trout (Oncorhynchus mykiss) were placed in net cages and flow through tanks in the river G?ta Alv, in western Sweden, during three different periods in 2004 and 2005. No differences between types of caging were found for any biomarker. Therefore, the results suggest that net cages and flow through tanks can be used and compared in environmental monitoring using biomarkers in caged rainbow trout. However, efforts should be taken to reduce differences in experimental conditions, e.g., light intensity and feeding levels.     

Modeling Changes to Streamflow,Sediment, and Nutrient Loading from Land Use Changes Due to Potential Natural Gas Development

Natural gas development using hydraulic fracturing has many potential environmental impacts, but among the most certain is the land disturbance required to build the well pads and other infrastructure required to drill and extract the gas. We used the Soil and Water Assessment Tool (SWAT) model to investigate how natural gas development could impact streamflow and sediment, total nitrogen (TN), and total phosphorous (TP) loadings in the upper Delaware River Basin (DRB), a relatively undeveloped watershed of 7,950 km² that lies above the Marcellus Shale formation. If gas development was permitted, our projections show the DRB could experience development of over 600 well pads to extract natural gas at build out, which, with supporting infrastructure (roads, gathering pipelines), could convert over 5,000 ha from existing land uses in the study area. In subbasins with development activity we found sediment, TN, and TP yields could increase by an average of 15, 0.08, and 0.03 kg/ha/yr, respectively (an increase of 2, 3, and 15%, respectively) for each one percent of subbasin land area converted into natural gas infrastructure. At the study area outlet on the Delaware River at Port Jervis, New York, we found increases in the annual average streamflow and sediment, nitrogen, and phosphorus loads of up to 0.01, 0.2, 0.2, and 1%, respectively, for a rapid development year, and 0.08, 1.3, 2.0, and 11%, respectively, for the full development scenario. Editor's note : This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series.     

Mass balance of decabromodiphenyl ethane and decabromodiphenyl ether in a WWTP

The additive flame retardant decabromodiphenyl ethane (deBDethane) has been identified in the environment, but little is known about its environmental behaviour. It is structurally similar to decabromodiphenyl ether (decaBDE), making it conceivable that it may also become an environmental contaminant of concern. In this study a mass balance of deBDethane and decaBDE was undertaken in a modern WWTP in Stockholm serving 7.05x10(5) inhabitants. Flow proportional samples of plant influent and effluent as well as daily grab samples of digested sludge were collected during two 7-day periods. All samples were analyzed with GC/HRMS using isotope labelled internal standards. The mean mass flows of deBDethane and decaBDE to the WWTP were 6.0 g per day and 55 g per day, respectively. Of this, less than 1% of both BFRs left the WWTP via the effluent, while the bulk was sequestered into the digested sludge, where the mean concentrations of deBDethane and decaBDE were 81 and 800 ng g(-1)d.wt., respectively. It is concluded that the transfer efficiency of deBDethane from the technosphere to the environment via WWTPs is similar to that of decaBDE.     

Aerosol Particle Number Concentration Measurements in Five European Cities Using TSI-3022 Condensation Particle Counter over a Three-Year Period during Health Effects of Air Pollution on Susceptible Subpopulations

Abstract

In this study, long-term aerosol particle total number concentration measurements in five metropolitan areas across Europe are presented. The measurements have been carried out in Augsburg, Barcelona, Helsinki, Rome, and Stockholm using the same instrument, a condensation particle counter (TSI model 3022). The results show that in all of the studied cities, the winter concentrations are higher than the summer concentrations. In Helsinki and in Stockholm, winter concentrations are higher by a factor of two and in Augsburg almost by a factor of three compared with summer months. The winter maximum of the monthly average concentrations in these cities is between 10,000 cm^-3 and 20,000 cm^-3, whereas the summer min is ?;5000–6000 cm^-3. In Rome and in Barcelona, the winters are more polluted compared with summers by as much as a factor of 4–10. The winter maximum in both Rome and Barcelona is close to 100,000 cm^-3, whereas the summer minimum is >10,000 cm^-3. During the weekdays the maximum of the hourly average concentrations in all of the cities is detected during the morning hours between 7 and 10 a.m. The evening maxima were present in Barcelona, Rome, and Augsburg, but these were not as pronounced as the morning ones. The daily maxima in Helsinki and Stockholm are close or even lower than the daily minima in the more polluted cities. The concentrations between these two groups of cities are different with a factor of about five during the whole day. The study pointed out the influence of the selection of the measurement site and the configuration of the sampling line on the observed concentrations.     

Spatial uncoupling of biodegradation, soil respiration, and PAH concentration in a creosote contaminated soil

Hotspots and coldspots of concentration and biodegradation of polycyclic aromatic hydrocarbons (PAHs) marginally overlapped at the 0.5-100 m scale in a creosote contaminated soil in southern Sweden, suggesting that concentration and biodegradation had little spatial co-variation. Biodegradation was substantial and its spatial variability considerable and highly irregular, but it had no spatial autocorrelation. The soil concentration of PAHs explained only 20-30% of the variance of their biodegradation. Soil respiration was spatially autocorrelated. The spatial uncoupling between biodegradation and soil respiration seemed to be governed by the aging of PAHs in the soil, since biodegradation of added ¹³C phenanthrene covaried with both soil respiration and microbial biomass. The latter two were also correlated with high concentrations of phospholipid fatty acids (PLFAs) that are common in gram-negative bacteria. However, several of the hotspots of biodegradation coincided with hotspots for the distribution of a PLFA indicative of fungal biomass.     

Selenium oxyanion inhibition of hydrogenotrophic and acetoclastic methanogenesis

Inhibitory effects of selenite and selenate towards hydrogenotrophic and acetoclastic methanogenesis were evaluated in anaerobic toxicity assays. The 50% inhibitory concentration (IC(50)) of both selenium oxyanions was below 6.1x10(-5)M in hydrogenotrophic assays, whereas acetoclastic methanogens were less inhibited: IC(50)=8.3x10(-5)M and 5.5x10(-4)M for selenite and selenate, respectively. Selenite completely inhibits methanogenesis from both substrates tested at concentrations 10(-3)M selenite, while only marginal methanogenic activities occur at equimolar concentrations of selenate. Selenite becomes irreversibly inhibitory upon a single exposure, whereas selenate inhibits methanogens upon repeated exposure. Consequently, methane recovery can be seriously hampered or even impossible during anaerobic treatment of highly selenium contaminated waste streams.