Decreased Runoff Response to Precipitation,Little Missouri River Basin,Northern Great Plains,USA

High variability in precipitation and streamflow in the semiarid northern Great Plains causes large uncertainty in water availability. This uncertainty is compounded by potential effects of future climate change. We examined historical variability in annual and growing season precipitation, temperature, and streamflow within the Little Missouri River Basin and identified differences in the runoff response to precipitation for the period 1976‐2012 compared to 1939‐1975 (n = 37 years in both cases). Computed mean values for the second half of the record showed little change (<5%) in annual or growing season precipitation, but average annual runoff at the basin outlet decreased by 22%, with 66% of the reduction in flow occurring during the growing season. Our results show a statistically significant (p < 0.10) 27% decrease in the annual runoff response to precipitation (runoff ratio). Surface‐water withdrawals for various uses appear to account for <12% of the reduction in average annual flow volume, and we found no published or reported evidence of substantial flow reduction caused by groundwater pumping in this basin. Results of our analysis suggest that increases in monthly average maximum and minimum temperatures, including >1°C increases in January through March, are the dominant driver of the observed decrease in runoff response to precipitation in the Little Missouri River Basin.     

THE ENHANCED ROLE OF WATER CONSERVATION IN THE COST-BENEFIT ANALYSIS OF WATER PROJECTS1

The concept of water conservation has increased in importance because of revisions in the rules and procedures for performing cost-benefit analyses of federal water projects. These revisions include a requirement that nonstructural and water conservation measures be incorporated into economic assessments of projects. Project analyses will now proceed as if water supplies were allocated “most effectively,” that is, to their highest valued uses. A related requirement provides that the net benefits of any project should now be valued using willingness to pay measures. A specific cost-benefit methodology accommodating the revisions is constructed and discussed. Informational requirements for applying this methodology are identified. In addition to being consistent with federal mandates, this technique offers important advantages over the traditional “requirements” approach to water supply planning.     

Links among nitrification, nitrifier communities, and edaphic properties in contrasting soils receiving dairy slurry

Soil biotic and abiotic factors strongly influence nitrogen (N) availability and increases in nitrification rates associated with the application of manure. In this study, we examine the effects of edaphic properties and a dairy (Bos taurus) slurry amendment on N availability, nitrification rates and nitrifier communities. Soils of variable texture and clay mineralogy were collected from six USDA-ARS research sites and incubated for 28 d with and without dairy slurry applied at a rate of ~300 kg N ha(-1). Periodically, subsamples were removed for analyses of 2 M KCl extractable N and nitrification potential, as well as gene copy numbers of ammonia-oxidizing bacteria (AOB) and archaea (AOA). Spearman coefficients for nitrification potentials and AOB copy number were positively correlated with total soil C, total soil N, cation exchange capacity, and clay mineralogy in treatments with and without slurry application. Our data show that the quantity and type of clay minerals present in a soil affect nitrifier populations, nitrification rates, and the release of inorganic N. Nitrogen mineralization, nitrification potentials, and edaphic properties were positively correlated with AOB gene copy numbers. On average, AOA gene copy numbers were an order of magnitude lower than those of AOB across the six soils and did not increase with slurry application. Our research suggests that the two nitrifier communities overlap but have different optimum environmental conditions for growth and activity that are partly determined by the interaction of manure-derived ammonium with soil properties.     

Observations of particle growth at a remote,Arctic site

Observations of particle size distributions suggest that particles grow significantly just above the snow surface at a remote, Arctic site. Measurements were made at Summit, Greenland (71.38°N and 31.98°W) at approximately 3200 m above sea level. No new particle formation was observed locally, but growth of ultrafine particles was identified by continuous evolution of the geometric mean diameter (GMD) during four events. The duration of the growth during events was between 24 and 115 h, and calculated event-average growth rates (GR) were 0.09, 0.30, 0.27, and 0.18 nm h^?1 during each event, respectively. Four-hour GR up to 0.96 nm h^?1 were observed. Events occurred during below- and above-average temperatures and were independent of wind direction. Correlation analysis of hourly-calculated GR suggested that particle growth was limited by the availability of photochemically produced precursor gases. Sulfuric acid played a very minor role in particle growth, which was likely dominated by condensation of organic compounds, the source of which was presumably the snow surface. The role of boundary layer dynamics is not definite, although some mixing at the surface is necessary for the observation of particle growth. Due to the potentially large geographic extent of events, observations described here may provide a link between long-range transport of mid-latitude pollutants and climate regulation in the remote Arctic.     

Mercury Balance on a Large Pulverized Coal-Fired Furnace

This paper presents results of a survey of mercury concentrations in coal, ash, water, fly ash, and flue gas discharges from a 5.5 × 10⁶ Ib/hr steam generator serving a 775 MW (net) turbine-generator set. Representative composite or grab samples were obtained for inlet coal and outlet ash and water. Stack samples were obtained for fly ash and mercury vapor emissions while the unit was operated at 660 MW (net) (85% of full load). Samples were analyzed by anodic stripping voltammetry, plasma emission spectroscopy, and neutron activation analysis to determine mercury concentration entering the furnace in the coal and leaving the furnace in the flue gas, fly ash, bottom and hopper ash, and water. Method inter-comparisons are discussed. A material balance for mercury has been calculated from fuel, ash, and stack gas flow rates. About 90% of the mercury in the coal is released and appears as vapor discharged in the stack gas while 10% remains in the residual ash. For a 700 MW (net) unit, about 5 lb/day of mercury vapor is released to the atmosphere.     

Developing a sustainable energy strategy for a water utility. Part II: A review of potential technologies and approaches

Environmental legislation is increasing the amounts of bought-in electricity required for sewage treatment, and generating larger volumes of sewage sludge to be treated and disposed of. Concurrently, concerns over global warming and food safety from sewage sludge recycling on agricultural land is augmenting the costs of conventional sewage and sludge treatment technologies and practices. This paper reviews some emerging technologies and practices that may assist in mitigating these problems in the future. In addition, a number of potential renewable energy technologies available to water companies are reviewed. Results suggest that through the take-up of new technologies, current and future water quality standards could be delivered in a more sustainable way. However, this series of papers also highlights that institutional and political conflicts may have inadvertently failed to recognise the wider effects of improving water quality and lessened the financial support necessary for their widespread take-up. It is also suggested that through the use of a Strategic Environmental Assessment (SEA) approach, stakeholders could gain a better understanding of the broader environmental effects of achieving certain water quality standards and develop policy and long-term investment strategies accordingly. However, to fulfill the information requirements of an SEA, an appropriate appraisal tool that considers many of these factors in unison is required, and a possible technique is suggested.     

The impact of organizational climate on safety climate and individual behavior

Relatively little previous research has investigated the meechanisms by which safety climate affects safety behavior. The current study examined the effects of general organizational climate on safety climate and safety performance. As expected, general organizational climate exerted a significant impact on safety climate, and safety climate in turn was related to self-reports of compliance with safety regulations and procedures as well as participation in safety-related activities within the workplace. The effect of general organizational climate on safety performance was mediated by safety climate, while the effect of safety climate on safety performance was partially mediated by safety knowledge and motivation.     

Job satisfaction and teamwork: the role of supervisor support

The link between teamwork and job satisfaction was investigated in a sample of 48 manufacturing companies comprising 4708 employees. Two separate research questions were addressed. First, it was proposed that supervisor support would be a weaker source of job satisfaction in companies with higher levels of teamworking. Multilevel analysis indicated that the extent of teamwork at the company level of analysis moderated the relationship between individual perceptions of supervisor support and job satisfaction. Second, it was proposed that the extent of teamwork would be positively related to perceptions of job autonomy but negatively related to perceptions of supervisor support. Further, it was proposed that the link between teamwork and job autonomy would be explained by job enrichment practices associated with teamwork. Analyses of aggregated company data supported these propositions and provided evidence for a complex mediational path between teamwork and job satisfaction. Implications for implementing teamwork in organizations are discussed. Copyright © 2001 John Wiley & Sons, Ltd.