Disinfection byproducts and halogen-specific total organic halogen speciation in chlorinated source waters – The impact of iopamidol and bromide

This study investigated the speciation of halogen-specific total organic halogen and disinfection byproducts(DBPs) upon chlorination of natural organic matter(NOM) in the presence of iopamidol and bromide(Br~-).Experiments were conducted with low bromide source waters with different NOM characteristics from Northeast Ohio,USA and varied spiked levels of bromide(2-30 μmol/L) and iopamidol(1-5 μmol/L).Iopamidol was found to be a direct precursor to trihalomethane(THM) and haloacetic acid formation,and in the presence of Br~-favored brominated analogs.The concentration and speciation of DBPs formed were impacted by iopamidol and bromide concentrations,as well as the presence of NOM.As iopamidol increased the concentration of iodinated DBPs(iodo-DBPs) and THMs increased.However,as Br~-concentrations increased,the concentrations of nonbrominated iodo-and chloro-DBPs decreased while brominated-DBPs increased.Regardless of the concentration of either iopamidol or bromide,bromochloroiodomethane(CHBrClI) was the most predominant iodo-DBP formed except at the lowest bromide concentration studied.At relevant concentrations of iopamidol(1 μmol/L) and bromide(2 μmol/L),significant quantities of highly toxic iodinated and brominated DBPs were formed.However,the rapid oxidation and incorporation of bromide appear to inhibit iodoDBP formation under conditions relevant to drinking water treatment.     

REGIONAL PATTERNS OF PESTICIDE CONCENTRATIONS IN SURFACE WATERS OF NEW YORK IN 19971

ABSTRACT: The predominant mixtures of pesticides found in New York surface waters consist of five principal components. First, herbicides commonly used on corn (atrazine, metolachlor, alachlor, cyanazine) and a herbicide degradate (deethylatrazine) were positively correlated to a corn‐herbicide component, and watersheds with the highest corn‐herbicide component scores were those in which large amounts of row crops are grown. Second, two insecticides (diazinon and carbaryl) and one herbicide (prometon) widely used in urban and residential settings were positively correlated to an urban/residential component. Watersheds with the highest urban/residential component scores were those with large amounts of urban and residential land use. A third component was related to two herbicides (EPTC and cyanazine) used on dry beans and corn, the fourth to an herbicide (simazine) and an insecticide (carbaryl) commonly used in orchards and vineyards, and the fifth to an herbicide (DCPA). Results of this study indicate that this approach can be used to: (1) identify common mixtures of pesticides in surface waters, (2) relate these mixtures to land use and pesticide applications, and (3) indicate regions where these mixtures of pesticides are commonly found.     

Hydrogeology of a restored coastal dune system in northeastern Scotland

This paper reports the results of 12 years of hydrological monitoring at the St. Fergus dune system in northeastern Scotland. The site is adjacent to the UK’s largest gas terminal and the dunes are crossed in five places by North Sea gas pipelines which were constructed between 1976 and 1990. These are buried beneath the dune system which was restored after pipeline installation. The dunes include a substantial freshwater wetland which is seasonally flooded and provides an important habitat for waterfowl. The hydrogeology of the site is characterized and the hydrogeological processes that sustain this wetland feature are considered including recent climatic fluctuations.     

Ensemble predictions and perceptions of risk,uncertainty, and error in flood forecasting

Under the auspices of the World Meteorological Organization, there are a number of international initiatives to promote the development and use of so-called ensemble prediction systems (EPS) for flood forecasting. The campaign to apply these meteorological techniques to flood forecasting raises important questions about how the probabilistic information these systems provide can be used for what in operational terms is typically a binary decision of whether or not to issue a flood warning. To explore these issues, we report on the results of a series of focus group discussions conducted with operational flood forecasters from across Europe on behalf of the European Flood Alert System. Working in small groups to simulate operational conditions, forecasters engaged in a series of carefully designed forecasting exercises using various different combinations of actual data from real events. Focus group data was supplemented by a follow-up questionnaire survey exploring how flood forecasters understand risk, uncertainty, and error. Results suggest that flood forecasters may not instinctively use ensemble predictions in the way that promoters of EPS perhaps think they should. The paper concludes by exploring the implications of these divergent ‘epistemic cultures’ for efforts to apply ensemble prediction techniques developed in the context of weather forecasting to the rather different one of flood forecasting.     

Beer,beef, and boards: the role of intermediaries in payment for ecosystem services arrangements in northwestern Montana

Payments for ecosystem or ecological services (PES) are voluntary, often market-based approaches to protecting environmental values. In the rural United States, some landowners receive PES through government led conservation programs, but little is known about their involvement in market based arrangements. We analyzed three examples of market based PES arrangements in northwestern Montana: watershed restoration and craft brewing, niche meat production, and certified timber supplies. We find that intermediaries were working between buyers and sellers in each case to set conditions for transactions and undertake the mechanics of implementation. These findings align with existing conceptualizations of intermediaries as crucial links in PES arrangements, but also suggest that intermediaries for market based PES arrangements are not always facilitators or neutral nongovernmental actors; they may actually be from the private sector and drive the process by serving as buyers. This research contributes to stronger understanding of the possibilities for local market based conservation in the rural West.     

Green-Tinted Glasses: How Do Pro-Environmental Citizens Conceptualize Environmental Sustainability?

Recent research has shown that many Australians see pro-environmental behaviour as desirable and identify as being green. However when compared to other countries, Australians score poorly on pro-environmental behaviour measures, engaging mostly in tokenistic pro-environmental actions, and demonstrate low levels of concern for the environment. In this article, we examine this tension through exploring the meaning of the term sustainability to Australian participants who self-identify as pro-environmental. Twenty-six interviews were conducted and analysed using a causal layered analysis. Through the examination of participants’ environmental discourse and practices, some of the deeper socio-psychological processes influencing pro-environmental behaviour are revealed. While participants aspired to be green, their actions were bound by cultural traditions and world views that perpetuate environmental degradation. Participants struggled to define the term sustainability and held self-enhancing motives for adopting what they identify as a pro-environmental identity. These findings highlight the influence of collective cultural constructs in shaping how pro-environmental behaviours are understood and enacted.     

Foraging areas differentially affect reproductive output and interpretation of trends in abundance of loggerhead turtles

Diet items and habitat constitute some of the environmental resources that may be used differently by individuals within a population. Long-term fidelity by individuals to particular resources exemplifies individual specialization, a phenomenon that is becoming increasingly recognized across a wide range of species. Less is understood about the consequences of such specialization. Here, we investigate the effects of differential foraging ground use on reproductive output in 183 loggerhead sea turtles (Caretta caretta) nesting at Wassaw Island, Georgia (31.89°N, 80.97°W), between 2004 and 2011 with resulting possible fitness effects. Stable isotope analysis was used to assign the adult female loggerheads to one of three foraging areas in the Northwest Atlantic Ocean. Our data indicate that foraging area preference influences the size, fecundity, and breeding periodicity of adult female loggerhead turtles. We also found that the proportion of turtles originating from each foraging area varied significantly among the years examined. The change in the number of nesting females across the years of the study was not a result of uniform change from all foraging areas. We develop a novel approach to assess differential contributions of various foraging aggregations to changes in abundance of a sea turtle nesting aggregation using stable isotopes. Our approach can provide an improved understanding of the influences on the causes of increasing or decreasing population trends and allow more effective monitoring for these threatened species and other highly migratory species.