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21.
Hackett AG Gustafson DI Moran SJ Hendley P van Wesenbeeck I Simmons ND Klein AJ Kronenberg JM Fuhrman JD Honegger JL Hanzas J Healy D Stone CT 《Journal of environmental quality》2005,34(3):877-889
A surface drinking water monitoring program for four corn (Zea mays L.) herbicides was conducted during 1995-2001. Stratified random sampling was used to select 175 community water systems (CWSs) within a 12-state area, with an emphasis on the most vulnerable sites, based on corn intensity and watershed size. Finished drinking water was monitored at all sites, and raw water was monitored at many sites using activated carbon, which was shown capable of removing herbicides and their degradates from drinking water. Samples were collected biweekly from mid-March through the end of August, and twice during the off-season. The analytical method had a detection limit of 0.05 microg L(-1) for alachlor [2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl)-acetamide] and 0.03 microg L(-1) for acetochlor [2-chloro-N-(ethoxymethyl)-N-(2-ethyl-6-methylphenyl)-acetamide], atrazine [6-chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine], and metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)-acetamide]. Of the 16528 drinking water samples analyzed, acetochlor, alachlor, atrazine, and metolachlor were detected in 19, 7, 87, and 53% of the samples, respectively. During 1999-2001, samples were also analyzed for the presence of six major degradates of the chloroacetanilide herbicides, which were detected more frequently than their parent compounds, despite having higher detection limits of 0.1 to 0.2 microg L(-1). Overall detection frequencies were correlated with product use and environmental fate characteristics. Reservoirs were particularly vulnerable to atrazine, which exceeded its 3 microg L(-1) maximum contaminant level at 25 such sites during 1995-1999. Acetochlor annualized mean concentrations (AMCs) did not exceed its mitigation trigger (2 microg L(-1)) at any site, and comparisons of observed levels with standard measures of human and ecological hazards indicate that it poses no significant risk to human health or the environment. 相似文献
22.
Damon M. Hall Gerardo R. Camilo Rebecca K. Tonietto Jeff Ollerton Karin Ahrné Mike Arduser John S. Ascher Katherine C. R. Baldock Robert Fowler Gordon Frankie Dave Goulson Bengt Gunnarsson Mick E. Hanley Janet I. Jackson Gail Langellotto David Lowenstein Emily S. Minor Stacy M. Philpott Simon G. Potts Muzafar H. Sirohi Edward M. Spevak Graham N. Stone Caragh G. Threlfall 《Conservation biology》2017,31(1):24-29
Research on urban insect pollinators is changing views on the biological value and ecological importance of cities. The abundance and diversity of native bee species in urban landscapes that are absent in nearby rural lands evidence the biological value and ecological importance of cities and have implications for biodiversity conservation. Lagging behind this revised image of the city are urban conservation programs that historically have invested in education and outreach rather than programs designed to achieve high‐priority species conservation results. We synthesized research on urban bee species diversity and abundance to determine how urban conservation could be repositioned to better align with new views on the ecological importance of urban landscapes. Due to insect pollinators’ relatively small functional requirements—habitat range, life cycle, and nesting behavior—relative to larger mammals, we argue that pollinators put high‐priority and high‐impact urban conservation within reach. In a rapidly urbanizing world, transforming how environmental managers view the city can improve citizen engagement and contribute to the development of more sustainable urbanization. 相似文献
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24.
Performance of newly implemented Environmental Management Systems in primary schools in South Africa
Luc Hens Torsten Wiedemann Schalk Raath Riana Stone Paul Renders Eric Craenhals 《Journal of environmental management》2010,91(4):906-917
Quantitative results from Environmental Management Systems (EMS) at primary schools have rarely been examined in literature. This paper presents the monitoring results of environmental care in 39 primary schools in Northern South Africa. During 2 years, after the EMS was implemented in the curriculum and in the school's management, the progress of environmental performances of the participating schools has been measured, by means of detailed questionnaires, related to four environmental aspects: water, waste, energy and greening. At the beginning of the project, 50% of the schools performed well on water-related environmental actions. Two years later it was 76%. For waste-related activities the improvement was even stronger: from 50% to 100%. The environmental performances of the schools improved also for greening-related actions, from 50% at the start of the project to 64% two years later. Only energy-related activities did not improve significantly with only 24% of all schools performing well at the end of the survey period.In general, the introduction of an EMS succeeded in an improvement of the overall environmental performances of the schools, but cost-intensive activities were less successful than others. 相似文献
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26.
Kenneth Walsh John Sherwell 《Journal of the Air & Waste Management Association (1995)》2013,63(10):1161-1175
Abstract In 1997, Maryland had no available ambient Federal Reference Method data on particulate matter less than 2.5 μm in aerodynamic diameter (PM2.5), but did have annual ambient data for PM smaller than 10 μm (PM10) at 24 sites. The PM10 data were analyzed in conjunction with local annual and seasonal zip-code-level emission inventories and with speciated PM2.5 data from four nearby monitors in the IMPROVE network (located in the national parks, wildlife refuges, and wilderness areas) in an effort to estimate annual average and seasonal high PM2.5 concentrations at the 24 PM10 monitor sites operating from 1992 to 1996. All seasonal high concentrations were estimated to be below the 24-hr PM2.5 National Ambient Air Quality Standards (NAAQS) at the sites operating in Maryland between 1992 and 1996. The estimates also indicated that 12 monitor sites might exceed the 3-year annual average PM2.5 NAAQS of 15 ug/m3, but Maryland’s air quality shows signs that it has been improving since 1992. The estimates also were compared with actual measurements after the PM2.5 monitor network was installed. The estimates were adequate for describing the chemical composition of the PM2.5, forecasting compliance status with the 24-hr and annual standards, and determining the spatial variations in PM2.5 across central Maryland. 相似文献
27.
OBJECTIVES: Zero tolerance (ZT) laws have been effective in reducing alcohol-related crashes among underage drivers. However, enforcement in some states has not been rigorous, and ZT offenses may not be viewed as serious offenses. On July 1, 1994, the state of Washington implemented a ZT law that allowed police to request a test for alcohol on suspicion of either a ZT or driving-under-the-influence (DUI) offense. The present study examined effects of the ZT law on arrests and case dispositions among underage offenders as a function of blood alcohol concentration (BAC) and post-law patterns of recidivism. METHODS: Times-series analyses examined the effects of the ZT law on trends in arrests of underage drivers between 1991 and 1999. Based on arrest records matched with driver's license records, the effects of the law on dispositions of alcohol-related offenses among underage drivers were examined, and rates of recidivism among underage offenders were examined for the period following the ZT law. RESULTS: There was a substantial increase in arrests of underage drivers beginning immediately after implementation of the ZT law, especially among drivers with low BACs. The types of court or administrative dispositions received by underage offenders changed markedly after the ZT law was implemented. Underage offenders with lower BACs became far more likely to receive alcohol-related convictions and/or license suspensions. However, the percentage of underage offenders with higher BACs receiving DUI convictions declined as some of these offenders received the lesser ZT disposition. After the ZT law, underage offenders with BACs of 0.10 g/dL or higher were more likely to recidivate than those with lower BACs, but appreciable proportions of drivers were re-arrested for another alcohol offense, whatever the BAC and however they were penalized. CONCLUSIONS: Implementation of Washington's law indicates that a ZT law can increase the likelihood that an underage person will be sanctioned for drinking and driving. However, recidivism remains an issue as more than one in four underage drivers arrested with low BACs subsequently were re-arrested. 相似文献
28.
Jayant A. Sathaye Kenneth Andrasko 《Mitigation and Adaptation Strategies for Global Change》2007,12(6):971-1000
Climate change programs have largely used the project-specific approach for estimating baseline emissions of climate mitigation
projects. This approach is subjective, lacks transparency, can generate inconsistent baselines for similar projects, and is
likely to have high transaction costs. The use of regional baselines, which partially addresses these issues, has been reported
in the literature on forestry and agriculture projects, and in greenhouse gas (GHG) mitigation program guidance for them (e.g.,
WRI/WBCSD GHG Project Protocol, USDOE’s 1605(b) registry, UNFCCC’s Clean Development Mechanism). This paper provides an assessment
of project-specific and regional baselines approaches for key baseline tasks, using project and program examples. The regional
experience to date is then synthesized into generic steps that are referred to as Stratified Regional Baselines (SRB). Regional
approaches generally, and SRB in particular explicitly acknowledge the heterogeneity of carbon density, land use change, and
other key baseline driver variables across a landscape. SRB focuses on providing guidance on how to stratify lands into parcels
with relatively homogeneous characteristics to estimate conservative baselines within a GHG assessment boundary, by applying
systematic methods to determine the boundary and time period for input data.
相似文献
Kenneth AndraskoEmail: |
29.
Kenneth T. Bowman 《Journal of the Air & Waste Management Association (1995)》2013,63(6):589-590
Increased energy processing activity in the north has resulted in a demand for measured data on plume dispersion that is relevant to this particular region. The north was, therefore, selected for study in a comprehensive government/Industry research program. The objective of these studies was to assess the behaviour of plumes in various geographic areas In Canada. The program utilizes airborne and automobile-mounted probes to determine SO2 and temperature profiles within stock-emitted plumes as well as meteorological data on local atmospheric structure. The data are then analyzed numerically to obtain plume axis elevations and standard deviations of spread and these results are compared to accepted predictive methods. Good agreement with the analysis of Briggs was observed for predicting the location of the plume axis In neutral conditions; some deviations were noted in stable conditions. Values of the measured product ( σay-σ;z) were generally larger than those of Pasquill, particularly for those values close to the source. A difference between the measured values of (σ;y-σ;z) in fall and winter was observed in stable conditions. 相似文献
30.
Option value is estimated for the Washakie Wilderness, northwest Wyoming, USA, using the contingent valuation technique. Consumer
surplus, the traditional measure of economic value, is estimated separately and compared with option value. Several populations
are tested, including Washakie visitors, Yellowstone National Park visitors, and residents from four metropolitan test markets:
Salt Lake City, Utah; Portland, Oregon; Nashville, Tennessee; and Orlando, Florida, USA. The average annual preservation option
value (consumer surplus) expressed by on-site wilderness visitors is $46.17 ($80.13), by urban residents is $9.70 ($8.97),
and by rural residents is $8.43 ($7.80). Four selected attributes are determined to be important in motivating option demand
for the Washakie, including existence value, bequest value, the desire for an on-site visit, and interest in securing the
visiting privileges of others. The results suggest that option value is important in wilderness valuation and that off-site
users account for a large part of the economic value of wilderness. 相似文献