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71.
Advocates of sustainable urban development often privilege the region as a scale for coordinated action and investment. However, discourses of sustainability institutionalised through regional planning, and conflated with notions of liveability, lend themselves to recruitment by competing, and opposing, development interests. To be regionally sustainable, an individual land development should, both on-site and through its connections to other sites, contribute to overall sustainability of the region. Using examples of industrial waterfront redevelopment in metropolitan Vancouver, we show how particular urban spaces are misrepresented as lynchpins of regional sustainability. In a plan for residential redevelopment, it is claimed that sustainable redevelopment will reunite citizens with “their waterfront”, reframed as liveable, pure, clean, ecologically vital and non-industrial. At an adjacent site, it is claimed that waterfront industrial land should be protected to combat industrial sprawl. Yet, in both cases the developers have lobbied for the expansion of road transportation making the claims of regional sustainability doubtful. 相似文献
72.
Eva C. Karau Pamela G. Sikkink Robert E. Keane Gregory K. Dillon 《Environmental management》2014,54(1):98-111
Both satellite imagery and spatial fire effects models are valuable tools for generating burn severity maps that are useful to fire scientists and resource managers. The purpose of this study was to test a new mapping approach that integrates imagery and modeling to create more accurate burn severity maps. We developed and assessed a statistical model that combines the Relative differenced Normalized Burn Ratio, a satellite image-based change detection procedure commonly used to map burn severity, with output from the Fire Hazard and Risk Model, a simulation model that estimates fire effects at a landscape scale. Using 285 Composite Burn Index (CBI) plots in Washington and Montana as ground reference, we found that an integrated model explained more variability in CBI (R 2 = 0.47) and had lower mean squared error (MSE = 0.28) than image (R 2 = 0.42 and MSE = 0.30) or simulation-based models (R 2 = 0.07 and MSE = 0.49) alone. Overall map accuracy was also highest for maps created with the Integrated Model (63 %). We suspect that Simulation Model performance would greatly improve with higher quality and more accurate spatial input data. Results of this study indicate the potential benefit of combining satellite image-based methods with a fire effects simulation model to create improved burn severity maps. 相似文献
73.
Matthew R. Gilg M. Camila Restrepo Ronald Walton Pamela M. Brannock Thomas J. Hilbish Emmanuel Rodriguez 《Marine Biology》2013,160(7):1737-1750
Divergence at gamete recognition loci is hypothesized to result in speciation in broadcast spawning invertebrates. Many gamete recognition loci evolve quickly and show patterns of positive selection, yet the advantage of divergence is rarely known. M7 lysin is a sperm protein in the Mytilus edulis species complex that shows evidence of adaptive evolution. This locus is polymorphic with two distinct clades within Mytilus galloprovincialis, one of which, the D clade, shows the strongest signal of positive selection. We tested whether the geographic patterns in allele frequency were consistent with the hypothesis that positive selection on D clade alleles (G D ) was due to reinforcement. Populations of M. edulis showed little evidence of introgression of G D alleles, but there was no consistent evidence of reproductive character displacement. The lack of consistent patterns expected of reinforcement suggests that another mechanism is likely responsible for the adaptive divergence of M7 lysin. 相似文献
74.
When a no‐notice emergency prompts an evacuation, family members in different locations throughout a city may unite so that they can evacuate as a group. This paper draws on data from more than 300 interviews conducted in the metropolitan area of Chicago, Illinois, United States. The study uses discrete choice models to analyse the expectations of respondents regarding whether their likely plans for evacuation involve gathering spouses, parents, adult‐age children, and/or non‐family members. In addition, it addresses the matter of whether respondents plan to reunite with family members at home. Individuals' access to a personal car is the dominating factor in predicting whether respondents plan to gather a spouse. Being the parent of a child under the age of 18 years increases the tendency to report planning to reunite with family members at home. Both commute mode and car availability are not significantly associated with plans to reunite at home. 相似文献
75.
This study examined individuals' beliefs about older workers. Of particular interest was the relationship between those beliefs and individuals' (a) interactions with older workers, (b) supervisory status, and (c) demographic variables. Findings indicated that although older workers hold more positive beliefs about older workers than younger workers hold, even younger workers tended to have generally positive beliefs. Chronological age was found to moderate two relationships. First, the number of younger workers' interactions with older workers significantly, positively affected younger workers' beliefs about older workers. Second, an examination of the interaction between supervisory status and age found that older supervisors hold more negative beliefs about older workers than younger supervisors. 相似文献
76.
Pamela MacQuarrie Lawrence C. Nkemdirim 《Journal of the American Water Resources Association》1991,27(1):73-82
ABSTRACT: This paper examines the relationship between both potential (E*) and nonpotential evapotranspiration and equilibrium evapotranspiration (EQ) in an irrigated wheat field in southcentral Alberta, Canada. The control exercised by surface wetness and root reservoir moisture content in determining the value of the Priestley-Taylor constant a is explored. Also investigated is the relationship between a and the vapor flux fraction ET/(R-G) where ET is the actual evapotranspiration, R the net radiation, and G the soil heat flux. It is shown that evapotranspiration occurred at the potential rate (E*) when the available soil moisture (ASM) within the root zone was ≥3 percent. a varied from 0.84 for a dry soil to 1.49 for a saturated soil. The mean a for E* was 1.24. Surface wetness sustained evapotranspiration at the potential rate when such wetting exceeded 2mm d?1 following a period of prolonged drawdown of soil moisture, α and ET/(R-G) were positively correlated and this correlation strengthened with increasing soil moisture for constant values of the energy partitioning factor s+γ/s where s is the slope of the saturation humidity-temperature curve and γ is the psychrometric constant. ET=EQ when ETI(R-G) lay within the range of 0.59 to 0.82 corresponding to Bowen ratio (β) values of 0.22 and 0.69, respectively. 相似文献
77.
Some of the greatest challenges for managing residential development occur at the interface between the terrestrial and aquatic ecosystems--in a lake's riparian area. Land use planners need a framework they can use to identify development hotspots, areas were the next push for development will most likely occur. Lake riparian development profiles provide a framework for linking ecological and social factors important to development. In a test of this framework in northern Minnesota, researchers identified seven constructs influencing riparian area development: current general development, current housing development, and availability, accessibility, suitability, aesthetics, and proximity to services. Profiles display a lake's value for each construct relative to the range of values for all lakes in the county. Maps, developed using indicators for several constructs, allow us to identify how the factors interact and are dispersed across the landscape. These profiles help policy makers, planners, and managers identify lakes that are potential development hotspots so they can take timely steps to manage development or control the impacts of development. 相似文献
78.
79.
The United Nations Population Fund (UNFPA) coordinated efforts to integrate RH into contingency planning for the 2003 Iraq crisis and the 2003 regional response for displaced populations in West Africa. Using UNFPA's network of country offices in the Middle East, staff developed logistics plans, conducted workshops and pre-positioned RH supplies. Though refugee movements did not occur, the contingency planning enhanced the response capacity of UNFPA offices and made it possible to rapidly provide assistance inside Iraq. In West Africa, multi-country workshops and follow-up resulted in country-level and regional action plans useful during the renewed crises of 2003; scarce funding, however, limited their full implementation. UNFPA's experiences show that contingency planning requires committing resources for crises, some of which will not occur; new staff skills; and follow-up. Moreover, RH is considered by some to be additional to the core elements of contingency planning. RH's political sensitivity, particularly with certain donors, further complicated integrated planning. 相似文献
80.
Artemisia californica, represented nearly 100% of the species present at the end of two growing seasons. Irrigation may speed revegetation under
some conditions, but was not very effective in establishing natural vegetation structure. 相似文献