Understanding the role of land use in urban stormwater quality management

Urbanisation significantly impacts water environments with increased runoff and the degradation of water quality. The management of quantity impacts are straight forward, but quality impacts are far more complex. Current approaches to safeguard water quality are largely ineffective and guided by entrenched misconceptions with a primary focus on 'end-of-pipe' solutions. The outcomes of a research study presented in the paper, which investigated relationships between water quality and six different land uses offer practical guidance in the planning of future urban developments. In terms of safeguarding water quality, high-density residential development which results in a relatively smaller footprint would be the preferred option. The research study outcomes bring into question a number of fundamental concepts and misconceptions routinely accepted in stormwater quality management. The research findings confirmed the need to move beyond customary structural measures and identified the key role that urban planning can play in safeguarding urban water environments.     

An assessment of household willingness to pay for curbside recycling: a comparison of payment card and referendum approaches

Curbside recycling is a tool that communities use to reduce the need for landfill space. This study provides contingent valuation estimates of household willingness to pay (WTP) to continue a curbside recycling program in the face of budget cuts. Comparisons of two forms of the contingent valuation method (CVM) are provided: a single bounded referendum and a payment card. Neither approach emerges as unambiguously superior. Response rates were virtually identical. Both approaches show that support for curbside recycling is highly sensitive to price. Regression results from the payment card provided a more thorough identification of socio-demographic variables associated with WTP than the referendum, but the explanatory power of the two regressions did not differ significantly. The referendum estimates of mean WTP exceed those from the payment card, although the disparities are less than those typically reported in the CVM literature. Local policy makers cited the CVM results as influencing their decisions regarding funding options for the future of the program, and seemed to appreciate the fact that the two approaches provided a fairly narrow range of estimates of WTP. In an era when more of the burden of financing of environmental programs is being shifted to the local level, use of CVM to estimate the WTP of consumers for highly disaggregated goods and services designed to achieve environmental improvement will likely become more relevant to local decision makers who are interested in understanding their constituents' views.     

Lying in negotiations: how individual and situational factors influence the use of neutralization strategies

Lying in negotiations can cause negative emotions, so participants may use neutralization strategies to reduce these feelings. We conducted a 2 (ethical versus non‐ethical climate) × 2 (low versus high negative consequences) experiment to examine how individual and situational factors affect the use of three such strategies: minimizing the lie, denigration of the target, and denial. Lying, psychological distress, and self‐perceived moral attributes were measured as non‐manipulated independent variables. One hundred and ninety‐two MBA students participated in a business negotiation in which they were provided with incentives to lie. As predicted, higher distress was associated with greater denial of lies. In addition, climate and consequences interacted to affect minimization and liars engaged in less minimization than did participants who merely concealed information. Climate and moral attributes interacted to affect denigration. We believe these findings support further study of neutralization strategies in the workplace. Copyright © 2005 John Wiley & Sons, Ltd.     

Modified Fenton's processes for effective in‐situ chemical oxidation—Laboratory and field evaluation

Fenton's reagent in its conventional form, although effective for contaminant treatment, is impractical from an in‐situ field application perspective due to low pH requirements (i.e., pH 3‐4), and limited reagent mobility when introduced into the subsurface. Modified Fenton's processes that use chelated‐iron catalysts and stabilized hydrogen peroxide have been developed with the goal of promoting effective in‐situ field application under native pH conditions (i.e., pH 5‐7), while extending the longevity of hydrogen peroxide. Laboratory experiments conducted in soil columns packed with organic soil to compare modified Fenton's catalysts with conventional catalysts (acidified iron [II]) indicated superior mobility and sorption characteristics for modified Fenton's catalysts. Furthermore, the acidic pH of a conventional catalyst was buffered to the native soil range, leading to increased iron precipitation/adsorption following permeation through the soil column. The chelates present within the modified Fenton's catalyst showed greater affinity toward iron compared with the native soil and, hence, minimized iron loss through adsorption during the permeation process even at pH 5‐7. Field effectiveness of the modified Fenton's process was demonstrated at a former dry‐cleaning facility located in northeast Florida. Preliminary laboratory‐scale experiments were conducted on soil‐slurry and groundwater samples to test the process efficacy for remediation of chlorinated solvents. Based on successful experimental results that indicated a 94 percent (soil slurry) to 99 percent (groundwater) reduction of cis‐1,2‐DCE, PCE, and TCE, a field‐scale treatment program was initiated utilizing a plurality of dual‐zone direct push injection points installed in a grid fashion throughout the site. Results of treatment indicated a 72 percent reduction in total chlorinated contamination detected in the site groundwater following the first injection event; the reduction increased to 90 percent following the second injection event. © 2002 Wiley Periodicals Inc.     

Learning in agriculture: building social capital in island communities

Social capital helps communities respond positively to change. Research in agricultural businesses and into managing change through learning in communities has highlighted the importance of relationships between people and the formal and informal infrastructure of communities to the quality of outcomes experienced by communities, businesses and individuals. Communities can be geographic communities—the data drawn on in this paper are from an island community, for example—or communities-of-common-purpose, such as agricultural organisations. This paper reviews research into managing change through learning and social capital, presents a model of the simultaneous building and use of social capital and explores the ways in which learning as part of an agricultural community can be used to bring benefits to geographic communities such as islands. The model presented in this paper stems from studies of the informal learning process that builds resilient communities. It conceptualises the way in which social capital is used and built in interactions between individuals. There are two stages to the model. The first stage depicts social capital at the micro level of one-on-one interactions where it is built and used. The second stage of the model is about the interrelationship of micro-level social capital processes with the community and societal-level social capital resources.     

Biodegradability of Urea-Aldehyde Condensation Products

Condensation products of urea and different aldehydes (formaldehyde, isobutyraldehyde, crotonaldehyde) are used in large amounts (more than 300,000 tons per year) as resins, binders, and insulating materials for industrial applications, as well as in controlled-release nitrogen fertilizer for greens, lawns, or bioremediation processes. The biodegradability of these condensates and the enzymic mechanism of their degradation was studied in mircoorganisms isolated from soil, which were able to use these compounds as the sole source of nitrogen for growth. Different pure cultures of both gram-positive and gram-negative bacteria completely degraded methylenediurea, dimethylenetriurea, isobutylidenediurea, and crotonylidenediurea to urea, ammonia, and the corresponding aldehydes and carbon dioxide. Enzymes initiating this degradation were purified and characterized and turned out to be different with regard to their regulation of expression, their physicobiochemical properties, and their reaction mechanism.     

The contribution of burnout to work performance

While the notion that ‘burnout’ is related to a decline in work performance is widely recognized, empirical support for this relationship is lacking. The present study, composed of human services personnel, is the first to empirically test the relationships among Maslach's three dimensions of burnout and work performance. A negative relationship was established between one dimension of burnout, emotional exhaustion, and subsequent work performance. However, the results failed to establish relationships among work performance, depersonalization and diminished personal accomplishment. These results provide further support for emotional exhaustion as a key component of the burnout experience. Future directions and implications of these findings are introduced. © 1997 John Wiley & Sons, Ltd.     

A test of value congruence effects

This study investigated value congruence effects on organizational commitment and job satisfaction. We used the competing values framework to measure values, and response‐surface methodology employing polynomial regression equations to investigate congruence effects. Our sample, 1,358 hospital employees, made judgments about their personal preferences for the four competing value sets—internal process, open systems, rational goal, and human relations. They also rated how much the same values were operating in the organization. We predicted that organizational commitment and job satisfaction would be maximized when a ‘match’ or ‘congruence’ occurred between the two component value measures. We evaluated congruence effects using the following criteria: (1) the proportion of variance explained by the overall equation was significant; (2) the quadratic and interaction terms were significant individually and as a set, and their signs were in the right direction; (3) the implied constraints were valid; and (4) no higher‐order terms beyond those indicated by the model were significant. The results indicated that although quadratic and interaction components were present in all eight models, they were weak in their support for congruence. The study's findings suggested that congruence effects were relatively unimportant compared to main effects in explaining variance in organizational commitment and job satisfaction, at least in the large organization we investigated in this study. Copyright © 1999 John Wiley & Sons, Ltd.     

Reduced sulfur compounds in gas from construction and demolition debris landfills

The biological conversion of sulfate from disposed gypsum drywall to hydrogen sulfide (H(2)S) in the anaerobic environment of a landfill results in odor problems and possible health concerns at many disposal facilities. To examine the extent and magnitude of such emissions, landfill gas samples from wells, soil vapor samples from the interface of the waste and cover soil, and ambient air samples, were collected from 10 construction and demolition (C&D) debris landfills in Florida and analyzed for H(2)S and other reduced sulfur compounds (RSC). H(2)S was detected in the well gas and soil vapor at all 10 sites. The concentrations in the ambient air above the surface of the landfill were much lower than those observed in the soil vapor, and no direct correlation was observed between the two sampling locations. Methyl mercaptan and carbonyl sulfide were the most frequently observed other RSC, though they occurred at smaller concentrations than H(2)S. This research confirmed the presence of H(2)S at C&D debris landfills. High concentrations of H(2)S may be a concern for employees working on the landfill site. These results indicate that workers should use proper personal protection at C&D debris landfills when involved in excavation, landfill gas collection, or confined spaces. The results indicate that H(2)S is sufficiently diluted in the atmosphere to not commonly pose acute health impacts for these landfill workers in normal working conditions. H(2)S concentrations were extremely variable with measurements occurring over a very large range (from less than 3 ppbv to 12,000 ppmv in the soil vapor and from less than 3 ppbv to 50 ppmv in ambient air). Possible reasons for the large intra- and inter-site variability observed include waste and soil heterogeneities, impact of weather conditions, and different site management practices.     

Characterization of phosphorus species in biosolids and manures using XANES spectroscopy

Identification of the chemical P species in biosolids or manures will improve our understanding of the long-term potential for P loss when these materials are land applied. The objectives of this study were to determine the P species in dairy manures, poultry litters, and biosolids using X-ray absorption near-edge structure (XANES) spectroscopy and to determine if chemical fractionation techniques can provide useful information when interpreted based on the results of more definitive P speciation studies. Our XANES fitting results indicated that the predominant forms of P in organic P sources included hydroxylapatite, PO(4) sorbed to Al hydroxides, and phytic acid in lime-stabilized biosolids and manures; hydroxylapatite, PO(4) sorbed on ferrihydrite, and phytic acid in lime- and Fe-treated biosolids; and PO(4) sorbed on ferrihydrite, hydroxylapatite, beta-tricalcium phosphate (beta-TCP), and often PO(4) sorbed to Al hydroxides in Fe-treated and digested biosolids. Strong relationships existed between the proportions of XANES PO(4) sorbed to Al hydroxides and NH(4)Cl- + NH(4)F-extractable P, XANES PO(4) sorbed to ferrihydrite + phytic acid and NaOH-extractable P, and XANES hydroxylapatite + beta-TCP and dithionite-citrate-bicarbonate (DCB)- + H(2)SO(4)-extractable P (r(2) = 0.67 [P = 0.01], 0.78 [P = 0.01], and 0.89 [P = 0.001], respectively). Our XANES fitting results can be used to make predictions about long-term solubility of P when biosolids and manures are land applied. Fractionation techniques indicate that there are differences in the forms of P in these materials but should be interpreted based on P speciation data obtained using more advanced analytical tools.