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431.
ABSTRACT: The City of Portland's stormwater management program, winner of EPA's Environmental Excellence Award for 1996, is committed to partnership-based, cost-effective, “green” approaches to healthy neighborhoods and water quality. The stormwater program encourages innovative, non-structural pollution reduction techniques like native landscaping, stormwater pollution reduction bioswales and ponds, and public involvement and education. Effectiveness of stormwater best management practices (BMPs) has been difficult to determine on a citywide basis. Recognizing this problem, the City of Portland launched the Parkrose Pilot Project in 1994 to test the effectiveness of a wide range of BMPs in a small watershed in north Portland, the Parkrose catchment, and monitor the results prior to citywide implementation. This catchment was selected because of its small size (144 acres), its representative mix of land uses, and an extensive record of water quality monitoring data. This paper examines the City's strategy in selecting the Parkrose study area as a pilot watershed, the BMPs chosen for use in the watershed, and the results of the program to date. Final success of the Parkrose project will be gauged by the attainment of measurable pollution reduction within the catchment while providing opportunities for meaningful participation by the local community in achieving water quality. Involvement by private citizens in the community is crucial to the success of the project and to ensure compliance with the federal mandate to reduce pollutants to the maximum extent practicable.  相似文献   
432.
Consistent individual differences in behavior, commonly termed animal personality, are a widespread phenomenon across taxa that have important consequences for fitness, natural selection, and trophic interactions. Animal personality research may prove useful in several conservation contexts, but which contexts remains to be determined. We conducted a structured literature review of 654 studies identified by combining search terms for animal personality and various conservation subfields. We scored the relevance of personality and conservation issues for each study to identify which studies meaningfully integrated the 2 fields as opposed to surface-level connections or vague allusions. We found a taxonomic bias toward mammals (29% of all studies). Very few amphibian or reptile studies applied personality research to conservation issues (6% each). Climate change (21%), invasive species (15%), and captive breeding and reintroduction (13%) were the most abundant conservation subfields that occurred in our search, though a substantial proportion of these papers weakly integrated conservation and animal personality (climate change 54%, invasive species 51%, captive breeding and reintroduction 40%). Based on our results, we recommend that researchers strive for consistent and broadly applicable terminology when describing consistent behavioral differences to minimize confusion and improve the searchability of research. We identify several gaps in the literature that appear to be promising and fruitful avenues for future research, such as disease transmission as a function of sociability or exploration as a driver of space use in protected areas. Practitioners can begin informing future conservation efforts with knowledge gained from animal personality research.  相似文献   
433.
Scientists, resource managers, and decision makers increasingly use knowledge coproduction to guide the stewardship of future landscapes under climate change. This process was applied in the California Central Valley (USA) to solve complex conservation problems, where managed wetlands and croplands are flooded between fall and spring to support some of the largest concentrations of shorebirds and waterfowl in the world. We coproduced scenario narratives, spatially explicit flooded waterbird habitat models, data products, and new knowledge about climate adaptation potential. We documented our coproduction process, and using the coproduced models, we determined when and where management actions make a difference and when climate overrides these actions. The outcomes of this process provide lessons learned on how to cocreate usable information and how to increase climate adaptive capacity in a highly managed landscape. Actions to restore wetlands and prioritize their water supply created habitat outcomes resilient to climate change impacts particularly in March, when habitat was most limited; land protection combined with management can increase the ecosystem's resilience to climate change; and uptake and use of this information was influenced by the roles of different stakeholders, rapidly changing water policies, discrepancies in decision-making time frames, and immediate crises of extreme drought. Although a broad stakeholder group contributed knowledge to scenario narratives and model development, to coproduce usable information, data products were tailored to a small set of decision contexts, leading to fewer stakeholder participants over time. A boundary organization convened stakeholders across a large landscape, and early adopters helped build legitimacy. Yet, broadscale use of climate adaptation knowledge depends on state and local policies, engagement with decision makers that have legislative and budgetary authority, and the capacity to fit data products to specific decision needs.  相似文献   
434.
At all levels, the understanding of uncertainty associated with risk of major chemical industrial hazards should be enhanced. In this study, a quantitative risk assessment (QRA) was performed for a knockout drum in the distillation unit of a refinery process and then probabilistic uncertainty analysis was applied for this QRA. A fault tree was developed to analyze the probability distribution of flammable liquid released from the overfilling of a knockout drum. Bayesian theory was used to update failure rates of the equipment so that generic information from databases and plant equipment real life data are combined to gain all available knowledge on component reliability. Using Monte Carlo simulation, the distribution of top event probability was obtained to characterize the uncertainty of the result. It was found that the uncertainty of basic event probabilities has a significant impact on the top event probability distribution. The top event probability prediction uncertainty profile showed that the risk estimation is improved by reducing uncertainty through Bayesian updating on the basic event probability distributions. The whole distribution of top event probability replaces point value in a risk matrix to guide decisions employing all of the available information rather than only point mean values as in the conventional approach. The resulting uncertainty guides where more information or uncertainty reduction is needed to avoid overlap with intolerable risk levels.  相似文献   
435.
Installation of effective safety measures to prevent and mitigate an accidental LNG release is critical. Water curtains are usually inexpensive, simple and reliable and currently have been recognized as an efficient technique to control and mitigate various hazards in the process industries including LNG industry. Actions of a water spray consist of a combination of several physical mechanisms. Detailed analysis of the complex mechanisms and the effects of water spray features to control and mitigate potential LNG vapor cloud are still unclear. This paper discusses the experimental research conducted by MKOPSC to study the physical phenomena involved and the effect of different types of water curtains parameters when applied for LNG vapor. The data from medium scale out-door experiments at the Brayton Fire Training School (BFTF), Texas, are summarized here to understand the relative importance of induced mechanical mixing effects, dilution with air, and heat transfer between water droplets and the LNG vapor. Field test results have determined that water curtains can reduce the concentration of the LNG vapor cloud. Due to the water curtain mechanisms of entrainment of air, dilution of vapor with entrained air, transfer of momentum and heat to the gas cloud, water curtain can disperse LNG vapor cloud to some extent.  相似文献   
436.
In the process industries, electrical circuit breakers are tripped for a variety of reasons including hazard prevention and mitigation. This paper will discuss the application of tripping electrical breakers for process safety reasons. It often occurs that a risk assessment study has determined the need to include the shutdown of a large electric motor as part of a safety instrumented function (SIF). In the process industries, it is common practice to control and protect large horsepower motors (typically 2000 HP and above), with medium-voltage switchgear breakers. Safety instrumented functions that include electric motors utilizing medium-voltage switchgear for tripping have unique final element subsystems, which require specialized knowledge in order to implement correctly. This paper will discuss the design considerations for integrating medium-voltage switchgear used for shutdown of an electric motor into a safety instrumented function. First, an overview of typical low and medium-voltage electrical equipment used for controlling and protecting electric motors will be discussed. Next, a review of generic sourced failure data for medium-voltage switchgear breakers will be presented. Focus will be on the taxonomy used to classify different breaker types and the relevant failure modes and effects used for quantifying performance. Next, specific SIF design details for tripping medium-voltage switchgear breakers will be analyzed in the context of achieving a certain integrity level. Parameters to be considered include hardware fault tolerance requirements, voting, available diagnostics, energize vs. de-energize to trip shutdown circuits, certified equipment vs. proven-in-use, and alternate means of shutdown (including manual intervention and protective relaying). This paper will also analyze the common electrical equipment that is shared among potential protection layers used to trip the same breaker, and determine how much credit can be taken considering common cause failure. Finally, inspection, test, and preventive maintenance (ITPM) of medium-voltage switchgear will be discussed as a means for maintaining the electrical equipment in the “as good as new” condition.  相似文献   
437.
White-nose syndrome (WNS) is a fungal disease that has caused precipitous declines in several North American bat species, creating an urgent need for conservation. We examined how microclimates and other characteristics of hibernacula have affected bat populations following WNS-associated declines and evaluated whether cooling of warm, little-used hibernacula could benefit bats. During the period following mass mortality (2013–2020), we conducted 191 winter surveys of 25 unmanipulated hibernacula and 6 manipulated hibernacula across Pennsylvania (USA). We joined these data with additional datasets on historical (pre-WNS) bat counts and on the spatial distribution of underground sites. We used generalized linear mixed models and model selection to identify factors affecting bat populations. Winter counts of Myotis lucifugus were higher and increased over time in colder hibernacula (those with midwinter temperatures of 3–6 °C) compared with warmer (7–11 °C) hibernacula. Counts of Eptesicus fuscus, Myotis leibii, and Myotis septentrionalis were likewise higher in colder hibernacula (temperature effects = –0.73 [SE 0.15], –0.51 [0.18], and –0.97 [0.28], respectively). Populations of M. lucifugus and M. septentrionalis increased most over time in hibernacula surrounded by more nearby sites, whereas Eptesicus fuscus counts remained high where they had been high before WNS onset (pre-WNS high count effect = 0.59 [0.22]). Winter counts of M. leibii were higher in hibernacula with high vapor pressure deficits (VPDs) (particularly over 0.1 kPa) compared with sites with lower VPDs (VPD effect = 15.3 [4.6]). Counts of M. lucifugus and E. fuscus also appeared higher where VPD was higher. In contrast, Perimyotis subflavus counts increased over time in relatively warm hibernacula and were unaffected by VPD. Where we manipulated hibernacula, we achieved cooling of on average 2.1 °C. At manipulated hibernacula, counts of M. lucifugus and P. subflavus increased over time (years since manipulation effect = 0.70 [0.28] and 0.51 [0.15], respectively). Further, there were more E. fuscus where cooling was greatest (temperature difference effect = –0.46 [SE 0.11]), and there was some evidence there were more P. subflavus in hibernacula sections that remained warm after manipulation. These data show bats are responding effectively to WNS through habitat selection. In M. lucifugus, M. septentrionalis, and possibly P. subflavus, this response is ongoing, with bats increasingly aggregating at suitable hibernacula, whereas E. fuscus remain in previously favored sites. Our results suggest that cooling warm sites receiving little use by bats is a viable strategy for combating WNS.  相似文献   
438.
In conservation, trust and justice are increasingly recognized as both intrinsically valuable and critical for successful socioecological outcomes. However, the interdependence between these concepts has not been explored. The conservation trust literature provides examples of efforts to build trust between conservationists and local actors; yet, these interventions are often conceived to incentivize local cooperation within dominant paradigms. We argue that when trust building is promoted as a technical fix that does not plan in advance to address power asymmetries in conservation practice, inequities may inadvertently be re-embedded. Therefore, we conceptualized a framework that joins trust, justice, and power so that critical analyses of conservation partnerships can be more effectively undertaken. We drew on environmental justice theory to better calibrate the trust literature for the historical-political settings of conservation, especially in the Global South. Justice and trust share strong theoretical links where perceptions of justice shape a willingness to trust, and, equally, trust is a precondition for justice to be perceived. Different forms of trust connect to varied domains of justice and power in different ways, which mediates the outcomes of interventions. We applied our framework to case studies to explore how these interdependences play out in practice. Failure of agencies to attend to issues of maldistribution, misrecognition of cultural values and knowledge, and exclusion from participation strongly compromised trust. Moreover, the ways in which nature-dependent communities and marginalized conservation workers are trusted, or the conditions under which they give trust, can lead to partnerships being perceived as just or unjust. Focusing on trust and justice can help identify power dynamics so they can be addressed more readily and create space for alternative understandings of partnerships.  相似文献   
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