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951.
Public concern over the consequences of forest fire to wildland interface communities has led to increased resources devoted to fire suppression, fuel treatment, and management of fire events. The social consequences of the decisions involved in these and other fire-related actions are largely unknown, except in an anecdotal sense, but do occur at a variety of temporal and social organizational scales. These consequences are not limited to the fire event itself. Preparation for the possibility of a fire, actions that suppression agencies take during a fire, and postfire decisions all have consequences, if unknown currently. This article presents an "event-based" approach that can be useful for constructing and systematic discussion about the consequences of wildland fire to human communities. For each of the three major periods within this approach, agencies, communities, and individuals make decisions and take actions that have consequences. The article presents an integrated, temporally based process for examining these consequences, which is similar to others developed in the natural hazards and disaster management literature. 相似文献
952.
Simon ML Cherry DS Currie RJ Zipper CE 《Environmental monitoring and assessment》2006,123(1-3):109-124
The Ely Creek watershed (Lee County, VA) was determined in 1995 to be the most negatively affected by acid mine drainage (AMD) within the Virginia coalfield. This determination led the US Army Corps of Engineers to design and build passive wetland remediation systems at two major AMD seeps affecting Ely Creek. This study was undertaken to determine if ecological recovery had occurred in Ely Creek. The results indicate that remediation had a positive effect on all monitoring sites downstream of the remediated AMD seeps. At the site most impacted by AMD, mean pH was 2.93 prior to remediation and improved to 7.14 in 2004. Benthic macroinvertebrate surveys revealed that one AMD influenced site had increased taxa richness from zero taxa in 1997 to 24 in 2004. While in situ testing of Asian clams resulted in zero survival at five of seven AMD influenced sites prior to remediation, some clams survived at all sites after. Clam survival was found to be significantly less than upstream references at only two sites, both downstream of un-mitigated AMD seeps in 2004. An ecotoxicological rating (ETR) system that combined ten biotic and abiotic parameters was developed as an indicator of the ecological status for each study site. A comparison of ETRs from before and after remediation demonstrated that all sites downstream of the remediation had experienced some level of recovery. Although the remediation has improved the ecological health of Ely Creek, un-mitigated AMD discharges are still negatively impacting the watershed. 相似文献
953.
Malcolm J. R. Clark Paul H. Whitfield 《Journal of the American Water Resources Association》1993,29(1):119-130
ABSTRACT: A model of comprehensive environmental monitoring process with integral quality assurance is presented. This model views the monitoring process as iterative cycles of a series of elements: design, plan, protocols, preparation, field liaison, sample collection, sample handling, laboratory analysis, data transmission, data validation, data approval, data provision, statistical analysis, and reporting. Quality assurance is linked to each element, not just to laboratory analysis. The program of quality assurance ensures that environmental monitoring data are compatible with the project goals, are comparable between various sampling agencies, and maintain a high degree of scientific credibility. The key characteristics of the overall quality assurance process are detailed documentation, timely resolution of problems, regular reporting, and routine independent audits. 相似文献
954.
955.
Initiation and resolution of jumping spider contests: roles for size, proximity, and early detection of rivals 总被引:3,自引:0,他引:3
Phillip W. Taylor Oren Hasson David L. Clark 《Behavioral ecology and sociobiology》2001,50(5):403-413
Animals are commonly expected to assess each other during contests in order to economically identify relative status. Escalated or long contests are expected to arise mainly when rivals have difficulty discriminating small differences. Results of the present study of male-male contests in Plexippus paykulli, a jumping spider (Salticidae) with acute vision, are not in accord with this widely held view. Despite the typical finding that size-advantaged rivals are more likely to win contests and that this tendency increases with size disparity, contest dynamics suggest that these tendencies are achieved in the absence of direct size assessment. In contests between different-sized spiders, maximum escalation and overall duration were predicted by the absolute size of the size-disadvantaged spider (usually the loser) rather than the size difference between the rivals. This result suggests that spiders base decisions of persistence on their own size, such that size-disadvantaged rivals usually reach their limits first, and then retreat. This interpretation is further supported by findings that maximum escalation and total duration were both positively related to size in contests between size-matched spiders. Spiders were more likely to win if they oriented and displayed first, and longer, more escalated, contests ensued if the size-disadvantaged spider was the first to orient and display. Proximity of rivals at contest outset also influenced contest dynamics, but not outcome. 相似文献
956.
Pricing Policy for Tourism in Protected Areas: Lessons from Komodo National Park, Indonesia 总被引:1,自引:0,他引:1
Abstract: Protected areas are under increasing pressure to provide economic justification for their existence, particularly in developing countries where demand for land and natural resources is high. Nature-based tourism offers a mechanism to generate substantial benefits from protected areas for both governments and local communities, and ecotourism is increasingly promoted as a sustainable use of protected areas. The extent to which ecotourism offsets the costs of a protected area has rarely been examined. We used financial data from Komodo National Park, Indonesia, and a willingness-to-pay questionnaire of independent visitors to (1) examine the financial contribution of tourism in offsetting the costs of tourism and wider management and (2) assess the effect of hypothetical fee increases on park revenues, visitation patterns, and local economies. Although only 6.9% of park management costs were recovered, visitors were willing to pay over 10 times the current entrance fee, indicating a substantial potential for increased revenue. The potential negative effect of large fee increases on visitor numbers and the resultant effect on local economic benefits from tourism may limit the extent to which greater financial benefits from Komodo National Park (KNP) can be realized. Our results suggest that a moderate, tiered increase in entrance fees is most appropriate, and that partial revenue retention by KNP would help demonstrate the conservation value of tourism to both visitors and managers and has the potential to increase visitors' willingness to pay. 相似文献
957.
Electrochemical systems provide a low cost, versatile, and controllable platform to potentially treat contaminants in water, including chlorinated solvents. Relative to bare metal or noble metal amended materials, dimensionally stable electrode materials such as mixed metal oxide coated titanium (Ti/MMO) have advantages in terms of stability and cost, important factors for sustainable remediation solutions. Here, we report the use of Ti/MMO as an effective cathode substrate for treatment of trichloroethene (TCE). TCE degradation in a batch reactor was measured as the decrease of TCE concentration over time and the corresponding evolution of chloride; notably, this occurred without the formation of commonly encountered chlorinated intermediates. The reaction was initiated when Ti/MMO cathode potentials were less than -0.8 V vs. the standard hydrogen electrode, and the rate of TCE degradation increased linearly with progressively more negative potentials. The maximum pseudo-first-order heterogeneous rate constant was approximately 0.05 cm min(-1), which is comparable to more commonly used cathode materials such as nickel. In laboratory-scale flow-though column reactors designed to simulate permeable reactive barriers (PRBs), TCE concentrations were reduced by 80-90%. The extent of TCE flux reduction increased with the applied potential difference across the electrodes and was largely insensitive to the spacing distance between the electrodes. This is the first report of the electrochemical reduction of a chlorinated organic contaminant at a Ti/MMO cathode, and these results support the use of this material in PRBs as a possible approach to manage TCE plume migration. 相似文献
958.
959.
Brown GS Betty RG Brockmann JE Lucero DA Souza CA Walsh KS Boucher RM Tezak MS Wilson MC 《Journal of environmental monitoring : JEM》2007,9(7):666-671
Vacuum filter socks were evaluated for recovery efficiency of powdered Bacillus atrophaeus spores from two non-porous surfaces, stainless steel and painted wallboard and two porous surfaces, carpet and bare concrete. Two surface coupons were positioned side-by-side and seeded with aerosolized Bacillus atrophaeus spores. One of the surfaces, a stainless steel reference coupon, was sized to fit into a sample vial for direct spore removal, while the other surface, a sample surface coupon, was sized for a vacuum collection application. Deposited spore material was directly removed from the reference coupon surface and cultured for enumeration of colony forming units (CFU), while deposited spore material was collected from the sample coupon using the vacuum filter sock method, extracted by sonication and cultured for enumeration. Recovery efficiency, which is a measure of overall transfer effectiveness from the surface to culture, was calculated as the number of CFU enumerated from the filter sock sample per unit area relative to the number of CFU enumerated from the co-located reference coupon per unit area. The observed mean filter sock recovery efficiency from stainless steel was 0.29 (SD = 0.14, n = 36), from painted wallboard was 0.25 (SD = 0.15, n = 36), from carpet was 0.28 (SD = 0.13, n = 40) and from bare concrete was 0.19 (SD = 0.14, n = 44). Vacuum filter sock recovery quantitative limits of detection were estimated at 105 CFU m(-2) from stainless steel and carpet, 120 CFU m(-2) from painted wallboard and 160 CFU m(-2) from bare concrete. The method recovery efficiency and limits of detection established in this work provide useful guidance for the planning of incident response environmental sampling for biological agents such as Bacillus anthracis. 相似文献
960.
Environmental forensics is an established discipline in North America, but has yet to make an impact within Europe and more specifically within the UK. In this paper we explore the reasons for this and explore the nature and fundamental philosophy that underlies this discipline. Case studies can be used to explore the complexity that can be associated with an environmental forensic investigation and we argue that there is a demand for professionals with skills in forensic practice within the environmental sector today. The paper finishes by suggesting that environmental forensics is a discipline of its moment within Europe for which the Higher Education sector must now cater. 相似文献