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101.
Riparian buffer restorations are used as management tools to produce favorable water quality impacts, moreover among the many benefits riparian buffers may provide, their application as instruments for water quality restoration rests on a relatively firm foundation of research. However, the extent to which buffers can restore riparian ecosystems; their functionality and species composition, are essentially unknown. In light of the foregoing, two broad areas of research are indicated. First, data are needed to document the relative effectiveness of riparian buffers that differ according to width, length, and plant species composition. These questions, of managing buffer dimension and species composition for functionality, are of central importance even when attenuation of nutrient and sediment loads alone are considered. Second, where ecosystem restoration is the goal, effects to in-stream and terrestrial riparian biota need to be considered. Relatedly, the effects of the restoration on the landscape need to be considered. Particularly, at what rate do the effects of the riparian buffer on in-stream water quality, biota, and habitat diminish downstream from restored sites? Answers to these important questions are needed, for streams and watersheds of different size and for areas of differing soil type within watersheds. U.S. EPA-NRMRL has initiated as research project that will document the potential for buffers to restore riparian ecosystems; focusing on water quality effects, but also, importantly, documenting effects on biota. While substantial riparian buffer management initiatives are already underway, the extent of landscapes that influence riparian ecosystems in the eastern United States is large; leaving ample opportunity for this suggested research to provide improved buffer designs in the future. The ultimate goal of research projects developed under this paradigm of ecosystem restoration is to develop data that are needed to implement riparian buffer restorations in the mid-Atlantic and elsewhere, especially the eastern United States.  相似文献   
102.
Journal of Material Cycles and Waste Management - The novel COVID-19 pandemic has disrupted the functioning of solid waste management globally as households experience an increase in their waste...  相似文献   
103.
Column experiments were performed to examine (a) the potential for leachate from construction and demolition (C&D) debris landfills to mobilize naturally-occurring iron and arsenic from soils underlying such facilities and (b) the ability of crushed limestone to remove these aqueous phase pollutants. In duplicate columns, water was added to a 30-cm layer of synthetic C&D debris, with the resulting leachate serially passed through a 30-cm soil layer containing iron and arsenic and a 30-cm crushed limestone layer. This experiment was conducted for two different soil types (one high in iron (10,400mg/kg) and the second high in iron (5400mg/kg) and arsenic (70mg/kg)); also monitored were control columns for both soil types with water infiltration alone. Despite low iron concentrations in the simulated C&D debris leachate, elevated iron concentrations were observed when leachate passed through the soils; reductive dissolution was concluded to be the cause of iron mobilization. In the soil containing elevated arsenic, increased iron mobilization from the soil was accompanied by a similar but delayed arsenic mobilization. Since arsenic sorbs to oxidized iron soil minerals, reductive dissolution of these minerals results in arsenic mobilization. Crushed limestone significantly reduced iron (to values below the detection limit of 0.01mg/L in most cases); however, arsenic was not removed to any significant extent.  相似文献   
104.
An increasing number of landfills are operated to accelerate waste decomposition through liquids addition (e.g., leachate recirculation) as a wet landfill. Landfill design and regulation often depend on utilizing landfill gas production models that require an estimate of a first-order gas generation rate constant, k. Consequently, several studies have estimated k using collected gas volumes from operating wet landfills. Research was conducted to examine an alternative approach in which k is estimated not from collected landfill gas but from solid waste samples collected over time and analyzed for remaining gas yield. To achieve this goal, waste samples were collected from 1990 through 2007 at two full-scale landfills in Florida that practiced liquids addition. Methane yields were measured from waste samples collected over time, including periods before and after leachate recirculation, and the results were applied to a first-order decay model to estimate rate constants for each of the sites. An initial, intensive processing step was conducted to exclude non-biodegradable components from the methane yield testing procedure. The resulting rate constants for the two landfills examined were 0.47 yr(-1) and 0.21 yr(-1). These results expectedly exceeded the United States Environmental Protection Agency's rate constants for dry and conventional landfills (0.02-0.05 yr(-1)), but they are comparable to wet landfill rate constants derived using landfill gas data (0.1-0.3 yr(-1)).  相似文献   
105.
We examined the direct and moderated effects of an ability‐based measure of emotional intelligence (MSCEIT© V2.0) on individual performance in a sample of business undergraduates. Controlling for general mental ability and personality, emotional intelligence explained unique incremental variance in performance ratings on only one of two measures of interpersonal effectiveness (public speaking effectiveness). However, the interaction of emotional intelligence with conscientiousness explained unique incremental variance both in public speaking and group behavior effectiveness, as well as academic performance (cumulative GPA). We conclude that the effects of emotional intelligence on performance are more indirect than direct in nature. Individuals must not only have emotional intelligence, but also must be motivated to use it. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
106.
A landfill reclamation project was considered to recover landfill airspace and soil, reduce future groundwater impacts by removing the waste buried in the unlined area, and optimize airspace use at the site. A phased approach was utilized to evaluate the technical and economic feasibility of the reclamation project; based on the results of these evaluations, approximately 6.8 ha of the unlined cells were reclaimed. Approximately 371,000 in-place cubic meters of waste was mined from 6.8 ha in this project. Approximately 230,600 cubic meters of net airspace was recovered due to beneficial use of the recovered final cover soil and reclaimed soil as intermediate and daily cover soil, respectively, for the current landfill operations. This paper presents the researchers’ landfill reclamation project experience, including a summary of activities pertaining to reclamation operations, an estimation of reclamation rates achieved during the project, project costs and benefits, and estimated composition of the reclaimed materials.  相似文献   
107.
108.
This paper compiles a detailed set of in situ chemical oxidation (ISCO) lessons learned pertaining to design, execution, and safety based on global experiences over the last 20 years. While the benefits of a “correct” application are known (e.g., cost effectiveness, speed, permanence of treatment), history also provides examples of a variety of “incorrect” applications. These provide an opportunity to highlight recurring themes that resulted in failures. ISCO is, and will continue to provide, an important remedial tool for site remediation, particularly as a component of a multifaceted approach for addressing large and complex sites. Future success, however, requires an objective understanding of both the benefits and the limitations of the technology. The ability to learn from the mistakes of the past provides an opportunity to eliminate, or at least minimize, them in the future. Over the last 25 years of ISCO application, process understanding and knowledge have improved and evolved. This paper combines a thorough discussion of lessons learned through decades of ISCO implementation throughout all aspects of ISCO projects with an analysis of changes to the ISCO remediation market. By discussing the interplay of these two themes and providing recommendations from collective lessons learned, we hope to improve the future of safe, cost‐effective, and successful applications of ISCO.  相似文献   
109.
Most disaster studies rely on convenience sampling and ‘after-only’ designs to assess impacts. This paper, focusing on Hurricane Harvey (2017) and leveraging a pre-/post-event sample of Greater Houston households (n=71) in the United States, establishes baselines for disaster preparedness and home structure flood hazard mitigation, explores household-level ramifications, and examines how preparedness and mitigation relate to health effects, event exposures, and recovery. Between 70 and 80 per cent of participants instituted preparedness measures. Mitigation actions varied: six per cent had interior drainage systems and 83 per cent had elevated indoor heating/cooling components. Sixty per cent reported home damage. One-half highlighted allergies and two-thirds indicated some level of post-traumatic stress (PTS). Three-quarters worried about family members/friends. The results of generalised linear models revealed that greater pre- event mitigation was associated with fewer physical health problems and adverse experiences, lower PTS, and faster recovery. The study design exposed the broad benefits of home structure flood hazard mitigation for households after Harvey.  相似文献   
110.
The problem of alcohol-related highway fatalities has led a majority of states to enact new legislative countermeasures. Because few states consistently collect information on alcohol involvement in fatal crashes, the evaluation of the effectiveness of these countermeasures has relied on surrogate measures of alcohol involvement. Using data from the U.S. Department of Transportation's Fatal Accident Reporting System (FARS), this study addresses the following questions: (a) Which of the several surrogate measures used are most likely to reflect alcohol involvement in fatal crashes? and (b) Do the trends in these surrogate measures provide an accurate appraisal of the true trends in alcohol-involved fatal crashes? The authors conclude that nighttime fatal crashes are the best surrogate measure of alcohol-involved crashes, but that surrogate measures may not accurately mirror trends in alcohol-involved fatal crashes over time, particularly in small states or over short durations. All drivers in fatal crashes should be given blood alcohol level (BAL) tests to most accurately assess the effects of drunk driving countermeasures.  相似文献   
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