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91.

This paper presents results of a study which examined how a mandatory wildfire evacuation affected members of Whitefish Lake First Nation 459, in Alberta, Canada. A qualitative case study approach was used, and semi-structured interviews were completed with 45 band members to learn about their evacuation experiences during the wildfire evacuation in May 2011 and explore the factors that complicated the evacuation process and put further strain on the evacuees and First Nation. This evacuation caused considerable distress for evacuees and had negative effects for the First Nation. Factors that affected evacuation experiences included: (1) transportation issues compounded by cultural land-use activities, (2) fear of home loss compounded by existing housing shortages, (3) information and lack of media interest, (4) language, (5) poverty, (6) large multi-generational families, (7) health concerns, and (8) reimbursement of evacuation-related expenses to the community. An overarching factor that affected the entire evacuation was jurisdiction. Based on these findings, recommendations are provided for emergency managers on improving wildfire evacuation experiences for Indigenous peoples.

  相似文献   
92.
The efficacy and feasibility of using zerovalent zinc (ZVZ) to treat 1,2,3‐trichloropropane (TCP)‐contaminated groundwater was assessed in laboratory and field experiments. In the first portion of the study, the reactivity of commercially available granular ZVZ toward TCP was measured in bench‐scale batch‐reactor and column experiments. These results were used to design columns for on‐site pilot‐scale treatment of contaminated groundwater at a site in Southern California. Two of the ZVZ materials tested were found to produce relatively high rates of TCP degradation as well as predictable behavior when scaling from bench‐scale to field testing. In addition, there was little decrease in the rates of TCP degradation over the duration of field testing. Finally, no secondary impacts to water quality were identified. The results suggest that ZVZ may be an effective and feasible material for use in engineered treatment systems, perhaps including permeable reactive barriers.  相似文献   
93.
Future extreme precipitation (EP, daily rainfall amount over certain thresholds) is projected to increase with global climate change; however, its effect on groundwater recharge has not been fully explored. This study specifically investigates the spatiotemporal dynamics of groundwater recharge and the effects of extreme precipitation (daily rainfall amount over the 95th percentile, which is tagged by ranking the percentiles in each season for a base period) on groundwater recharge from 1950 to 2010 over the Northern High Plains (NHP) Aquifer using the Soil Water Balance Model. The results show that groundwater recharge significantly (p < 0.05) increased in the eastern NHP from 1950 to 2010, where the highest annual average groundwater recharge occurs compared to the central and the western NHP. In the eastern NHP, 45.1% of the annual precipitation fell as EP, which contributed 56.8% of the annual total groundwater recharge. In the western NHP, 30.9% of the annual precipitation fell as extreme precipitation, which contributed 62.5% of the annual total groundwater recharge. In addition, recharge by extreme precipitation mainly occurred in late spring and early summer, before the maximum evapotranspiration rate, which usually occurs in mid‐summer until late fall. A dry site in the western NHP and a wet site in the eastern NHP were analysed to indicate how recharge responds to EP with different precipitation regimes. The maximum daily recharge at the dry site exceeded the wet site when there was EP. When precipitation fell as non‐extreme rainfall, most recharge was less than 5 mm at both the dry and wet sites, and the maximum recharge at the dry site became lower than the wet site. This study shows that extreme precipitation plays a significant role in determining groundwater recharge. © 2016 The Authors Hydrological Processes Published by John Wiley & Sons Ltd.  相似文献   
94.
Vibration-based structural identification is an essential technique for assessing structural conditions by inferring information from the dynamic characteristics of structures. However, the robustness of such techniques in monitoring the progressive damage of real structures has been validated with only a handful of research efforts, largely due to the paucity of monitoring data recorded from damaged structures. In a recent experimental program, a mid-rise cold-formed steel building was constructed at full scale atop a large shake table and subsequently subjected to a unique multi-hazard scenario including earthquake, post-earthquake fire, and finally post-fire earthquake loading. Complementing the simulated hazard events, low-amplitude vibration tests, including ambient vibrations and white noise base excitation tests, were conducted throughout the construction and the test phases. Using the vibration data collected during the multi-hazard test program, this paper focuses on understanding the modal characteristics of the cold-formed steel building in correlation with the construction and the structural damage progressively induced by the simulated hazard events. The modal parameters of the building (i.e., natural frequencies, damping ratios, and mode shapes) are estimated using two input–output and two output-only time-domain system identification techniques. Agreement between the evolution of modal parameters and the observations of the progression of physical damage demonstrates the effectiveness of the vibration-based system identification techniques for structural condition monitoring and damage assessment.  相似文献   
95.
New Zealand estuaries and harbours are subjected to increasing sediment deposition that can smother and bury infaunal communities, yet how coastal species respond to sediment deposition is not well understood. Here, we experimentally examined the effects of native marine sediment deposition on the NZ cockle (Austrovenus stutchburyi). Cockles were found to be highly mobile and capable burrowers, able to resurface within days from beneath 2–25?cm of sediment where no physical disturbance to their natural orientation occurred. Cockles were also resilient to daily (2?cm) reburials. However, following disturbance to their natural orientation, inverted cockles were significantly impeded when buried under 5–10?cm of sediment, with fewer adults resurfacing than sub-adults. Cockle populations are likely to be resilient to native sediment deposition, unless physically disturbed. When disturbed from their natural orientation in the sediment, higher mortality of larger adult-sized cockles would be predicted, with mortality increasing under thicker sediment deposits.  相似文献   
96.
97.
Mathematical Geosciences - Mesh generation lies at the interface of geological modeling and reservoir simulation. Highly skewed or very small grid cells may be necessary to accurately capture the...  相似文献   
98.
Rates of in situ microbial sulfate reduction in response to geochemical perturbations were determined using Native Organism Geochemical Experimentation Enclosures (NOGEEs), a new in situ technique developed to facilitate evaluation of controls on microbial reaction rates. NOGEEs function by first trapping a native microbial community in situ and then subjecting it to geochemical perturbations through the introduction of various test solutions. On three occasions, NOGEEs were used at the Norman Landfill research site in Norman, Oklahoma, to evaluate sulfate-reduction rates in wetland sediments impacted by landfill leachate. The initial experiment, in May 2007, consisted of five introductions of a sulfate test solution over 11 d. Each test stimulated sulfate reduction with rates increasing until an apparent maximum was achieved. Two subsequent experiments, conducted in October 2007 and February 2008, evaluated the effects of concentration on sulfate-reduction rates. Results from these experiments showed that faster sulfate-reduction rates were associated with increased sulfate concentrations. Understanding variability in sulfate-reduction rates in response to perturbations may be an important factor in predicting rates of natural attenuation and bioremediation of contaminants in systems not at biogeochemical equilibrium.  相似文献   
99.
In this work, the analytical and numerical solutions for modeling miscible gas and water injection into an oil reservoir are presented. Conservation laws with three levels of complexity are considered. Only the most complex model has the correct phase behavior for the example system, which is a multicontact miscible condensing gas drive with simultaneous water and gas injection. Example displacements in which one or both of the simpler models result in accurate simulations in a fraction of the computation time are presented, along with an example in which neither simplified thermodynamic model achieves a truly satisfactory result. A methodology is presented that can be used to establish the accuracy of simplified models in 1-D simulation based on convergence to analytical solutions for the full three-phase system.  相似文献   
100.
Optimization of groundwater and other subsurface resources requires analysis of multiple‐well systems. The usual modeling approach is to apply a linear flow equation (e.g., Darcy's law in confined aquifers). In such conditions, the composite response of a system of wells can be determined by summating responses of the individual wells (the principle of superposition). However, if the flow velocity increases, the nonlinear losses become important in the near‐well region and the principle of superposition is no longer valid. This article presents an alternative method for applying analytical solutions of non‐Darcy flow for a single‐ to multiple‐well systems. The method focuses on the response of the central injection well located in an array of equally spaced wells, as it is the well that exhibits the highest pressure change within the system. This critical well can be represented as a single well situated in the center of a closed square domain, the width of which is equal to the well spacing. It is hypothesized that a single well situated in a circular region of the equivalent plan area adequately represents such a system. A test case is presented and compared with a finite‐difference solution for the original problem, assuming that the flow is governed by the nonlinear Forchheimer equation.  相似文献   
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