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261.
Several researchers have examined the role of microfinance institutions (MFIs) in poverty alleviation, but the part that they play in disaster risk reduction remains unaddressed. Through an empirical study of Hatiya Island, one of the most vulnerable coastal communities of Bangladesh, this research evaluates perceptions of MFI support for the disaster risk reduction, response, and recovery process. The findings reveal no change in relation to risk reduction and income and occupation aspects for more than one‐half of the clients of MFIs. In addition, only 26 per cent of them have witnessed less damage as a result of being members of MFIs. One can argue, though, that the longer the membership time period the better the disaster preparedness, response, and recovery process. The outcomes of this study could help to guide the current efforts of MFIs to enhance the ability of coastal communities to prepare for and to recover from disasters efficiently and effectively.  相似文献   
262.
The electric system is experiencing rapid growth in the adoption of a mix of distributed renewable and fossil fuel sources, along with increasing amounts of off-grid generation. New operational regimes may have unforeseen consequences for air quality. A three-dimensional microscale chemical transport model (CTM) driven by an urban wind model was used to assess gaseous air pollutant and particulate matter (PM) impacts within ~10 km of fossil-fueled distributed power generation (DG) facilities during the early afternoon of a typical summer day in Houston, TX. Three types of DG scenarios were considered in the presence of motor vehicle emissions and a realistic urban canopy: (1) a 25-MW natural gas turbine operating at steady state in either simple cycle or combined heating and power (CHP) mode; (2) a 25-MW simple cycle gas turbine undergoing a cold startup with either moderate or enhanced formaldehyde emissions; and (3) a data center generating 10 MW of emergency power with either diesel or natural gas-fired backup generators (BUGs) without pollution controls. Simulations of criteria pollutants (NO2, CO, O3, PM) and the toxic pollutant, formaldehyde (HCHO), were conducted assuming a 2-hr operational time period. In all cases, NOx titration dominated ozone production near the source. The turbine scenarios did not result in ambient concentration enhancements significantly exceeding 1 ppbv for gaseous pollutants or over 1 µg/m3 for PM after 2 hr of emission, assuming realistic plume rise. In the case of the datacenter with diesel BUGs, ambient NO2 concentrations were enhanced by 10–50 ppbv within 2 km downwind of the source, while maximum PM impacts in the immediate vicinity of the datacenter were less than 5 µg/m3.

Implications: Plausible scenarios of distributed fossil generation consistent with the electricity grid’s transformation to a more flexible and modernized system suggest that a substantial amount of deployment would be required to significantly affect air quality on a localized scale. In particular, natural gas turbines typically used in distributed generation may have minor effects. Large banks of diesel backup generators such as those used by data centers, on the other hand, may require pollution controls or conversion to natural gas-fired reciprocal internal combustion engines to decrease nitrogen dioxide pollution.  相似文献   

263.
Tran P  Shaw R  Chantry G  Norton J 《Disasters》2009,33(1):152-169
Linking community knowledge with modern techniques to record and analyse risk related data is one way of engaging and mobilising community capacity. This paper discusses the use of the Geographic Information System (GIS) at the local level and the need for integrating modern technology and indigenous knowledge into disaster management. It suggests a way to mobilise available human and technical resources in order to strengthen a good partnership between local communities and local and national institutions. The paper also analyses the current vulnerability of two communes by correlating hazard risk and loss/damage caused by disasters and the contribution that domestic risk maps in the community can make to reduce this risk. The disadvantages, advantages and lessons learned from the GIS flood risk mapping project are presented through the case study of the Quang Tho Commune in Thua Thien Hue province, central Viet Nam.  相似文献   
264.
Bench-scale sand column breakthrough experiments were conducted to examine atrazine removal in agricultural infiltrate by Agrobacterium radiobacter J14a (J14a) immobilized in phosphorylated-polyvinyl alcohol compared to free J14a cells. The effects of cell loading and infiltration rate on atrazine degradation and the loss of J14a were investigated. Four sets of experiments, (i) tracers, (ii) immobilized dead cells, (iii) immobilized cells, and (iv) free cells, were performed. The atrazine biodegradation at the cell loadings of 300, 600, and 900 mg dry cells L(-1) and the infiltration rates of 1, 3, and 6 cm d(-1) were tested for 5 column pore volumes (PV). The atrazine breakthrough results indicated that the immobilized dead cells significantly retarded atrazine transport. The atrazine removal efficiencies at the infiltration rates of 1, 3, and 6 cm d(-1) were 100%, 80-97%, and 50-70%, respectively. Atrazine degradation capacity for the immobilized cells was not significantly different from the free cells. Both infiltration rate and cell loading significantly affected atrazine removal for both cell systems. The bacterial loss from the immobilized cell system was 10-100 times less than that from the free cell system. For long-term tests at 50 PV, the immobilized cell system provided consistent atrazine removal efficiency while the atrazine removal by the free cells declined gradually because of the cell loss.  相似文献   
265.
Laboratory experiments suggest that strong acids promote formation of enhanced levels of secondary organic aerosol (SOA), and organic aerosols may contribute to the health impacts of fine PM. We report results from examining hourly speciated fine particle data for evidence of ambient aerosol acidity-catalyzed SOA formation, as indicated by larger increases in the concentrations of organic aerosol mass occurring on days and in locations where more acidic aerosol (lower NH4+/SO4= molar ratios) exists. Data sets from the southeastern U.S. were examined for which hourly acidity of PM2.5 aerosols could be estimated, and for which hourly organic carbon (OC) content had been measured simultaneously. Within-day organic aerosol changes during selected periods were statistically related to concurrent aerosol acidity levels estimated from nitrate-corrected ammonium-to-sulfate ratios. Data from the Look Rock, TN, TVA/IMPROVE site for mid-July to mid-August 2004 showed average compositions frequently as acidic as NH4HSO4, however, no apparent increases in OC levels with increasing aerosol acidity were observed, even when [OC] changes were compared with time-delayed aerosol acidity estimates. SEARCH network data (2003–2004) for rural Centreville, AL (CTR) and Yorkville, GA (YRK) sites were also examined. Warm-season acidity levels were higher at CTR than at YRK, and daytime levels exceeded those at night at both sites. At the YRK site no consistent positive correlations were found between changes in OC or TC levels and aerosol acidity, even with time lags up to 6 h. Aerosol acidity at this site, however, is relatively low due to nearby agricultural sources of NH3. In contrast, during selected periods from April to October 2004, at CTR, 6-h lagged OC changes were weakly correlated with daytime, nitrate-corrected NH4+/SO4= molar ratios, but distinguishing this apparent relationship from meteorological effects on measured OC levels is challenging.  相似文献   
266.
Public lands and waters in the United States traditionally have been managed using frameworks and objectives that were established under an implicit assumption of stable climatic conditions. However, projected climatic changes render this assumption invalid. Here, we summarize general principles for management adaptations that have emerged from a major literature review. These general principles cover many topics including: (1) how to assess climate impacts to ecosystem processes that are key to management goals; (2) using management practices to support ecosystem resilience; (3) converting barriers that may inhibit management responses into opportunities for successful implementation; and (4) promoting flexible decision making that takes into account challenges of scale and thresholds. To date, the literature on management adaptations to climate change has mostly focused on strategies for bolstering the resilience of ecosystems to persist in their current states. Yet in the longer term, it is anticipated that climate change will push certain ecosystems and species beyond their capacity to recover. When managing to support resilience becomes infeasible, adaptation may require more than simply changing management practices—it may require changing management goals and managing transitions to new ecosystem states. After transitions have occurred, management will again support resilience—this time for a new ecosystem state. Thus, successful management of natural resources in the context of climate change will require recognition on the part of managers and decisions makers of the need to cycle between “managing for resilience” and “managing for change.”  相似文献   
267.
The Arctic is undergoing biological and environmental changes, and a coordinated effort to monitor is critical to detect these changes. The Circumpolar Biodiversity Monitoring Programme (CBMP) of the Arctic Council biodiversity working group, Conservation of Arctic Flora and Fauna (CAFF), has developed pan-Arctic biodiversity monitoring plans that aims to improve the ability to detect and report on long-term changes. Whilst introducing this special issue, this paper also presents the making of the terrestrial monitoring plan and discusses how the plan follows the steps required for an adaptive and ecosystem-based monitoring programme. In this article, we discuss how data on key findings can be used to inform circumpolar and global assessments, including the State of the Arctic Terrestrial Biodiversity Report, which will be the first terrestrial assessment made by the CBMP. Key findings, advice for future monitoring and lessons learned will be used in planning next steps of pan-Arctic coordinated monitoring.  相似文献   
268.
This essay builds from Samantha Senda-Cook's 2013 article, “Materializing Tensions,” to explore the material rhetorics of the so-called “social trails” of the Apostle Islands National Lakeshore. These improvised, foot-worn pathways, diverging from and running alongside official Park Service trails, materialize a tension between what Michel de Certeau termed “strategies” and “tactics,” revealing how both are always at play in park and preserve trailspace and how the movements of the individual trail walker actualize and perpetuate a common concept of place. The study demonstrates and advocates close rhetorical attention to material aspects of the biophysical environment and the way that physical traces of many individuals over time can influence the subsequent actions and interpretations of others. The final discussion argues that as further tensions in trailspace rhetorics are identified rhetorical analysis must not fail to account for them.  相似文献   
269.
Nitrous acid is an important component of nighttime N-oxide chemistry, and provides a significant source of both OH and NO in polluted urban air masses shortly after sunrise. Several recent studies have called for new sources of HONO to account for daytime levels much higher than are consistent with current understanding. However, measurement of HONO is problematic, with most in-situ techniques reporting higher values than simultaneous optical measurements by long-path DOAS, especially during daytime. The discrepancy has been attributed to positive interference in the in-situ techniques, negative interference in DOAS retrievals, the difficulty of comparing the different air masses sampled by the methods, or combinations of these.During August and September 2006, HONO mixing ratios from collocated long-path DOAS and automated mist-chamber/ion chromatograph (MC/IC) systems ranged from several ppbv during morning rush hour to daytime minima near 100 pptv. Agreement between the two techniques was excellent across this entire range during many days, showing that both instruments accurately measured HONO during this campaign. A small bias towards higher LP-DOAS observations at night can be attributed to slow vertical mixing leading to pronounced HONO profiles. A positive daytime bias of the MC/IC instrument during several days in late August/early September was correlated with photochemically produced compounds such as ozone, HNO3 and HCHO, but not with NO2, NOx, HO2NO2, or the NO2 photolysis rate. While an interferant could not be identified organic nitrites appear a possible explanation for our observations.  相似文献   
270.
Numerous emission and air quality modeling studies have suggested the need to accurately characterize the spatial and temporal variations in on-road vehicle emissions. The purpose of this study was to quantify the impact that using detailed traffic activity data has on emission estimates used to model air quality impacts. The on-road vehicle emissions are estimated by multiplying the vehicle miles traveled (VMT) by the fleet-average emission factors determined by road link and hour of day. Changes in the fraction of VMT from heavy-duty diesel vehicles (HDDVs) can have a significant impact on estimated fleet-average emissions because the emission factors for HDDV nitrogen oxides (NOx) and particulate matter (PM) are much higher than those for light-duty gas vehicles (LDGVs). Through detailed road link-level on-road vehicle emission modeling, this work investigated two scenarios for better characterizing mobile source emissions: (1) improved spatial and temporal variation of vehicle type fractions, and (2) use of Motor Vehicle Emission Simulator (MOVES2010) instead of MOBILE6 exhaust emission factors. Emissions were estimated for the Detroit and Atlanta metropolitan areas for summer and winter episodes. The VMT mix scenario demonstrated the importance of better characterizing HDDV activity by time of day, day of week, and road type. More HDDV activity occurs on restricted access road types on weekdays and at nonpeak times, compared to light-duty vehicles, resulting in 5-15% higher NOx and PM emission rates during the weekdays and 15-40% lower rates on weekend days. Use of MOVES2010 exhaust emission factors resulted in increases of more than 50% in NOx and PM for both HDDVs and LDGVs, relative to MOBILE6. Because LDGV PM emissions have been shown to increase with lower temperatures, the most dramatic increase from MOBILE6 to MOVES2010 emission rates occurred for PM2.5 from LDGVs that increased 500% during colder wintertime conditions found in Detroit, the northernmost city modeled.  相似文献   
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