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21.
Newburn, David A. and Richard T. Woodward, 2011. An Ex Post Evaluation of Ohio’s Great Miami Water Quality Trading Program. Journal of the American Water Resources Association (JAWRA) 48(1): 156‐169. DOI: 10.1111/j.1752‐1688.2011.00601.x Abstract: Market‐based approaches to address water quality problems have resulted in only limited success, especially in trading programs involving both point and nonpoint sources. We analyze one of the largest point‐nonpoint trading programs – the Great Miami Trading Program in Ohio, administered by the Miami Conservancy District (MCD). Our evaluation focuses on the economic and institutional aspects of the program, including cost effectiveness, efficiency of bidding, transaction costs, trading ratios, and innovation. We use a unique dataset consisting of all bids from agricultural nonpoint sources and interviews of soil and water conservation district (SWCD) agents in the watershed. We find that the MCD’s reliance on county‐level SWCD offices to recruit and advise farmers has been essential to achieve relatively high rates of farmer participation. Additionally, the MCD is able to partly free ride on the administrative costs that SWCD offices receive to assist federal conservation programs, which is helpful to lower costs for a fledgling trading program. However, the involvement of SWCD offices reduced the potential cost savings from the reverse auction structure because some agents were able to learn about the threshold price over the six rounds of bidding and help farmers bid strategically. Overall, the program structure serves as an effective model for future trading programs in other regions that seek to involve agricultural nonpoint sources.  相似文献   
22.
Schedule 11 of the Environment Act 1995 underpins the requirement for consultation on air quality issues. The ongoing air quality review and assessment process represents one of the largest locally based science policy and communication initiatives ever undertaken in the UK. This paper outlines the practice of consultation and communication for Air Quality Management (AQM) and reviews the interaction between Environmental Health professionals, as the leading actor in the AQM process and other stakeholders involved in air quality consultation, including the public. Results are presented from a widespread questionnaire survey of English local authorities. Data indicate that the majority of air quality consultation has been carried out with statutory consultees (by sending the review and assessment reports) and the public (via websites and leaflets) in the form of information dissemination.  相似文献   
23.
Arora, Kapil, Steven K. Mickelson, Matthew J. Helmers, and James L. Baker, 2010. Review of Pesticide Retention Processes Occurring in Buffer Strips Receiving Agricultural Runoff. Journal of the American Water Resources Association (JAWRA) 46(3):618-647. DOI: 10.1111/j.1752-1688.2010.00438.x Abstract: Review of the published results shows that the retention of the two pesticide carrier phases (runoff volume and sediment mass) influences pesticide mass transport through buffer strips. Data averaged across different studies showed that the buffer strips retained 45% of runoff volume (ranging between 0 and 100%) and 76% of sediment mass (ranging between 2 and 100%). Sorption (soil sorption coefficient, Koc) is one key pesticide property affecting its transport with the two carrier phases through buffer strips. Data from different studies for pesticide mass retention for weakly (Koc < 100), moderately (100 < Koc < 1,000), and strongly sorbed pesticides (Koc > 1,000) averaged (with ranges) 61 (0-100), 63 (0-100), and 76 (53-100) %, respectively. Because there are more data for runoff volume and sediment mass retention, the average retentions of both carrier phases were used to calculate that the buffer strips would retain 45% of weakly to moderately sorbed and 70% of strongly sorbed pesticides on an average basis. As pesticide mass retention presented is only an average across several studies with different experimental setups, the application of these results to actual field conditions should be carefully examined.  相似文献   
24.
An economic analysis of nonpoint source pollution management was conducted for the Nansemond River and Chuckatuck Creek watersheds in Southeast Virginia. The potential effects of alternative public policies on farm income, land use, and pollution loadings were investigated. Regulatory programs could have quite different impacts depending on which pollutant is targeted. Cost-share rates greater than 50 percent would have little additional effect on pollution from crop enterprises, but would reduce pollution from livestock  相似文献   
25.
Two field experiments were carried out in the watersheds of two Ramsar wetland areas, Lakes Koronia and Volvi (area A) and Lakes Mikri and Megali Prespa (area B), to study the effect of application of N fertilizer on wheat yields, the quality of runoff water, and the quality of stream water. The treatments were a combination of two methods of fertilizer application (total amount in fall, and 2/3 in fall + 1/3 in spring) at three rates (0, 100, and 200 kg N/ha) with four replications. Concentrations of NH4 +, NO3 , NO2 , P, and Cl and pH were determined in all water samples. Runoff water quality was not influenced by fertilizer application in either area. Chemical parameters for water did not differ along the selected watercourses in area B, while in area A they were higher in the samples taken near Lake Koronia than in the samples taken upstream, indicating that the watercourses are polluted downstream by nonagricultural sources. The differences in wheat yields between the 100 and 200 kg N/ha application rates were not high. These results call for better fertilizer management in order to achieve better yields and to diminish the possibility to have negative effects to the environment.  相似文献   
26.
ABSTRACT: Control of stormwater runoff from impervious surfaces is an important national goal because of disruptions to downstream ecosystems, water users, and property owners caused by increased flows and degraded quality. One method for reducing stormwater is the use of vegetated (green) roofs, which efficiently detain and retain stormwater when compared to conventional (black) roofs. A paired green roof‐black roof test plot was constructed at the University of Georgia and monitored between November 2003 and November 2004 for the green roof's effectiveness in reducing stormwater flows. Stormwater mitigation performance was monitored for 31 precipitation events, which ranged in depth from 0.28 to 8.43 cm. Green roof precipitation retention decreased with precipitation depth; ranging from just under 90 percent for small storms (< 2.54 cm) to slightly less than 50 percent for larger storms (> 7.62 cm). Runoff from the green roof was delayed; average runoff lag times increased from 17.0 minutes for the black roof to 34.9 minutes for the green roof, an average increase of 17.9 minutes. Precipitation and runoff data were used to estimate the green roof curve number, CN = 86. This information can be used in hydrologic models for developing stormwater mitigation programs.  相似文献   
27.
Daniel Maxwell 《Disasters》2007,31(S1):S25-S39
Food aid is a key component of a humanitarian response but its use in other programming contexts is subject to numerous criticisms. Even in humanitarian emergencies food aid is often late, unreliable and out of proportion to other elements of the response. Three major factors will shape the future of food aid. First, mechanisms of food aid governance are being reviewed and may undergo major changes—particularly the Food Aid Convention now that hopes have diminished for an Agreement on Agriculture at the World Trade Organisation. The second significant factor is donor agency trends. Overall levels of food aid have dropped fairly steadily in recent decades and there are several discernible trends in resource allocation, procurement and the use of food aid. The third factor is an emerging body of best practice that will define acceptable standards of food aid programming in the future.  相似文献   
28.
ABSTRACT: Recently, Congress designated irrigated agriculture under the “nonpoint source” category, covered by Section 208 of P.L. 92-500 and involves the use of “best management practices.” Generally, the most appropriate solutions for pollution abatement from irrigated agriculture involve the delivery and use of water rather than the treatment of irrigation return flows. 1. Technological alternatives should be utilized that are sensitive to local conditions and acceptable to the farmers. 2. Informational and educational programs to assist farm operators individually and collectively must be instituted prior to the start of the project; imaginatively conceived, and continuously modified and upgraded if motivation for change is to be encouraged. 3. Technical assistance personnel should be given short courses in skills needed for working effectively with irrigators. 4. Communication techniques used for working with farmers as individuals and groups should be designed into the implementation program and evaluated. 5. Credibility and trustworthiness of Federal and state agencies in the eyes of the irrigators provide the important final ingredient in effectively implementing change and reducing nonpoint source pollution from irrigated agriculture.  相似文献   
29.
Abstract

Bangladesh is on target for achieving the Millennium Development Goal 4 relating to infant and under-five mortality because of very rapid reduction in mortality in recent years. But this rate of reduction may be difficult to sustain and may hamper the achievement of Millennium Development Goal 4. Therefore, the main objective of this paper is to discuss and compare the different covariates of infant and under-five mortality in the context of overall country, urban and rural levels of Bangladesh using discriminant analysis. For this, the data are taken from Bangladesh Demographic and Health Survey, 2004. In discriminant analysis, the stepwise procedure has been picked up and only the significant variables are ranked according to the rank of Wilk’s Lambda values. The canonical discriminant function coefficients (unstandardized and standardized) for the predictor variables have also been calculated. Both the results show that breastfeeding is the most important variable in discriminating the two groups of mothers, i.e., mothers experiencing to infant mortality or not and mothers experiencing to under-five mortality or not. The related results of discriminant function also indicate that the discriminant function is statistically significant and discriminates well. Therefore, improvements in the health system are essential for promoting the breastfeeding practices (both inclusive and exclusive), which may be the effective strategies to reach families and communities with targeted messages and information.  相似文献   
30.
We discuss how confirmatory factor analysis results should be used to examine potential higher‐order constructs and advocate that researchers present five types of evidence, which are as follows: (1) the ability of the higher‐order model to reproduce the observed covariation among manifest variables; (2) the ability of the higher‐order model to reproduce the observed covariation among manifest variables better than more parsimonious alternative models—and no less well than less parsimonious alternative models; (3) the ability of the higher‐order model to reproduce the observed covariation among lower‐order factors; (4) the ability of the higher‐order factor to explain variation in lower‐order factors; and (5) the ability of the higher‐order factor to explain variation in manifest variables. We illustrate how this type of evidence could be presented with a worked example and contrast our recommendations with the manner in which higher‐order confirmatory factor analysis has been used in the organizational sciences over the past 25 years to support claims regarding higher‐order constructs such as core self‐evaluations and transformational leadership. Our review shows that a substantial proportion of the 44 examined articles failed to present enough evidence to allow readers to understand the size and importance of higher‐order factors. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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