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161.
The purpose of this paper is to describe a comprehensive approach for studying the interrelationships between the affective and the typological characteristics of the dwelling environment. The approach has a dual orientation: the observation of people's interaction with their habitat as it is designed, simulated and experienced during the design process (with the use of a spatial simulator) and the recollection of past experiences of the dwelling environment during their life-cycle. After describing the context of a current research project, which includes the design of a housing cooperative, the theoretical and methodological framework of the approach is discussed with respect to other studies in the field of environmental psychology. To conclude this paper an example of the kinds of results that can be obtained leads to a discussion with concluding remarks.  相似文献   
162.
163.
Building resilient food systems in the context of climate change and increased natural disasters depends on governance being more ‘adaptive’. Through a case study of events surrounding the extensive flooding that occurred in Queensland, Australia, in 2011, this paper examines how governance settings and processes affected food system actors’ engagement with three aspects of adaptive governance – responsibility, participation and collaboration – as those actors sought to ensure food availability and access during the crisis. We found that, despite the existence of formal governance instruments committed to disaster management, food security and resilience at local, state and national levels, responsibilities for ensuring food supply during a disaster were not clearly articulated. Responsibility was largely assumed by supermarkets, who in turn increased the influence of retailer–government coalitions. The participation of non-supermarket food system actors in governance was low, and there was limited collaboration between local, and other, levels of governance. The policy challenge is to ensure that responsibility, participation and collaboration become a stronger foci for adaptive governance during and after a disaster such as flooding.  相似文献   
164.
Experiments in which organisms are reared in treatments simulating current and future pCO2 concentrations are critical for ocean acidification (OA) research. The majority of OA exposure experiments use average atmospheric pCO2 levels as a baseline treatment. We conducted an ecoregion-scale analysis of global carbon chemistry datasets. For many locales, atmospheric pCO2 levels are not an appropriate characterization of marine carbon chemistry. We argue that atmospheric pCO2 should be disregarded when setting baseline treatment conditions and experimental design should rely on measurements of carbon chemistry in a study subject’s habitat. As carbon chemistry conditions vary with space and time, we suggest using a range of pCO2 values as a control rather than a single value. We illustrate this issue with data on the habitat of Euphausia pacifica, which currently lives in waters with a pCO2 around 900 μatm, a concentration much higher than the current global atmospheric mean.  相似文献   
165.
We examined the cost of conserving species as climate changes. We used a Maxent species distribution model to predict the ranges from 2000 to 2080 of 74 plant species endemic to the forests of Madagascar under 3 climate scenarios. We set a conservation target of achieving 10,000 ha of forest cover for each species and calculated the cost of achieving this target under each scenario. We interviewed managers of projects to restore native forests and conducted a literature review to obtain the net present cost per hectare of management actions to maintain or establish forest cover. For each species, we added hectares of land from lowest to highest cost per additional year of forest cover until the conservation target was achieved throughout the time period. Climate change was predicted to reduce the size of species' ranges, the overlap between species' ranges and existing or planned protected areas, and the overlap between species' ranges and existing forest. As a result, climate change increased the cost of achieving the conservation target by necessitating successively more costly management actions: additional management within existing protected areas (US$0-60/ha); avoidance of forest degradation (i.e., loss of biomass) in community-managed areas ($160-576/ha); avoidance of deforestation in unprotected areas ($252-1069/ha); and establishment of forest on nonforested land within protected areas ($802-2710/ha), in community-managed areas ($962-3226/ha), and in unprotected areas ($1054-3719/ha). Our results suggest that although forest restoration may be required for the conservation of some species as climate changes, it is more cost-effective to maintain existing forest wherever possible.  相似文献   
166.
Cuticular hydrocarbons have been identified as the source of sex-recognition signals for many insects, but for social insects, specifically ants, cuticular hydrocarbon profiles of males are often ignored. This study reports male-specific cuticular hydrocarbon patterns for the trap-jaw ant Odontomachus brunneus. Analysis of samples from four Florida populations demonstrated that male-specific overabundance of four hydrocarbons is conserved across populations despite population-level divergence of the remainder of the profile. In addition, hydrocarbon patterns unique to adult males were not present on the cuticle of final instar male larvae, indicating that male-specific profiles arise late in development. The pattern of an abundant subset of conserved cuticular hydrocarbons characteristic of males across divergent populations was compared to earlier findings of the conservation of fertility signals of females across these same populations.  相似文献   
167.
Environmental Fluid Mechanics - We investigated temporal variations in turbidity in Base Mine Lake, an oil sands pit lake, located in northeast Alberta, Canada. The lake has a surface area of...  相似文献   
168.
This article presents data on ambient concentrations of selected acidic aerosols at four existing monitoring sites in the Pittsburgh PA metropolitan area. The data were collected by staff of the Allegheny County Health Department, Division of Air Quality during the summer and fall of 1993. The sampling protocol was focused on obtaining 24 h-average ammonia, ammonium, acidic sulfates, and particle strong acids data on a 2 to 3 day cycle. The data were obtained using Harvard University School of Public Health's “Short-HEADS” annular denuder sampling train. The Pittsburgh area is of interest because it is downwind of a major regional source of sulfur and nitrogen emissions from coal-burning power plants: the Ohio River Valley. The data presented here indicate that ground-level concentrations of acidic aerosols in Pittsburgh are highly correlated spatially and that many pollutants are higher on days when ground-level wind direction vectors indicate that wind is coming from the southwest rather than from the Pittsburgh source area itself. The monitoring site that is most upwind of the Pittsburgh source area – South Fayette – has particle strong acid levels about twice those of sites closer in to the Pittsburgh central business district.  相似文献   
169.
Traffic-generated air pollutant emissions can be classified into exhaust and non-exhaust emissions. Increased attention is focussing on non-exhaust emissions as exhaust emissions are progressively limited by regulations. To characterise metal-rich emission from abrasion processes, size-segregated analysis of atmospheric aerosol particles sampled with micro-orifice uniform deposit impactors (MOUDI) in March 2007 in London was performed. The samples were collected at a roadside and a background site and were analysed for Al, Ba, Cu, Fe, Sb, Ti, V, Zn, Ca2+, K+, Mg2+, Na+, and NH4+. Most components showed a clear roadside increment, which was evident as a higher mass concentration and a change in the size distribution. In particular, Fe, Cu, Ba, and Sb correlated highly, indicative of a common traffic-related source. Using complementary information on the fleet composition, vehicle number and average speed, the brake wear emission was calculated using the EMEP/CORINAIR emission database. The total PM10 and barium emission of the traffic was determined by ratio to NOx whose source strength was estimated from published emission factors. Barium was found to comprise 1.1% of brake wear (PM10) particles from the traffic fleet as a whole, allowing its use as a quantitative tracer of brake wear emissions at other traffic-influenced sites.  相似文献   
170.
Radical chemistry in the nocturnal urban boundary layer is dominated by the nitrate radical, NO3, which oxidizes hydrocarbons and, through the aerosol uptake of N2O5, indirectly influences the nitrogen budget. The impact of NO3 chemistry on polluted atmospheres and urban air quality is, however, not well understood, due to a lack of observations and the strong impact of vertical stability of the boundary layer, which makes nocturnal chemistry highly altitude dependent.Here we present long-path DOAS observations of the vertical distribution of the key nocturnal species O3, NO2, and NO3 during the TRAMP experiment in Summer 2006 in Houston, TX. Our observations confirm the altitude dependence of nocturnal chemistry, which is reflected in the concentration profiles of all trace gases at night. In contrast to other study locations, NO3 chemistry in Houston is dominated by industrial emissions of alkenes, in particular of isoprene, isobutene, and sporadically 1,3-butadiene, which are responsible for more than 70% of the nocturnal NO3 loss. The nocturnally averaged loss of NOx in the lowest 300 m of the Houston atmosphere is ~0.9 ppb h?1, with little day-to-day variability. A comparison with the daytime NOx loss shows that NO3 chemistry is responsible for 16–50% of the NOx loss in a 24-h period in the lowest 300 m of the atmosphere. The importance of the NO3 + isoprene/1,3-butadiene reactions implies the efficient formation of organic nitrates and secondary organic aerosol at night in Houston.  相似文献   
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