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311.
There is a general lack of knowledge as regards the effects of climate change on pollutant behavior. This is particularly true of the Asia-Pacific Region (APR). This region has major significance in terms of global pollutant emission and also displays a wide variety of environments. This review presents the authors’ opinions on possible implications of climate change for pollutant behavior in the APR. Although differing responses can be expected across the region, there are clear implications as regards the short- and long-term behavior of pollutants. Effects can be predicted through modeling, but further data are required for model calibration. Nevertheless, it can be predicted that climate change will affect processes including global distillation of persistent organic pollutants, airborne transport of heavy metals, half-life of readily degradable pollutants, and eutrophication in water bodies. Particulates are expected to play a central role in mediating the effects of climate change, and successful predictive models will need to be based on particulate-mediated transport and behavior. Climate change also has the potential to cause an increase in the intensity and frequency of harmful algal blooms in aquatic environments throughout the region, with significant implications for supply of both food and drinking water.  相似文献   
312.
Disasters and environmental degradation create serious problems all around the world. They are inherently linked, but little attention is paid to their interaction, particularly at local levels. The degree of integration of disaster management and risk analysis with environmental management programs in relation to human vulnerability has been examined in Thua Thien Hue Province, Central Viet Nam. Unsustainable agricultural practices, and inappropriate development programs have contributed substantially to the increase of disaster risks. On the other hand, disasters damage natural resources and reduce environmental quality, indirectly contributing to increasing poverty which in turn, adds to the vulnerability of both natural and human systems, so further increasing disaster losses. Notwithstanding, in Viet Nam, there is a big gap between disaster and environment management policies and programs. In order to bridge the gap, an integrated approach in which environment-disaster linkage, rural—urban linkage, and poverty are brought into focus as core aspects of disaster management.  相似文献   
313.
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   
314.
Forest transitions may significantly contribute to climate change mitigation but also change forest use, affecting the local people benefiting from forests. We analyze forest transitions as contested processes that simplify multifunctional landscapes and alter local livelihoods. Drawing on the Theory of Access, we develop a conceptual framework to investigate practices of multifunctional forest use and the mechanisms that exclude local forest use(r)s during forest transitions in nineteenth century Austria and twenty-first century Lao PDR. Based on historical sources, interviews and secondary literature, we discuss legal, structural and social-metabolic mechanisms to exclude multifunctional forest practices, marginalizing peasants and shifting cultivators. These include, for example, the increasing enforcement of private ownership in forests or the shift from fuelwood to coal in Austria and restrictive land use planning or the expansion of private land concessions in Laos. By integrating political ecology and environmental history in forest transitions research we unravel shifting power relations connected to forest change.  相似文献   
315.
This study focuses on the degradation of the sulfonamide antibiotics, sulfadiazine, sulfamethazine, sulfamethoxazole, and sulfathiazole, using ultraviolet irradiation in various conditions. Different pHs were investigated in combination with the addition of hydrogen peroxide and further oxygen removal. High-performance liquid chromatography electrospray ionization ion-trap mass spectrometry was used to identify and elucidate degradation products and to establish concentration–time curves. Previously unknown degradation products could be characterized. Reaction rate constants of all compounds and transformation products were determined. The parent sulfonamides decayed according to first-order kinetics, while the concentrations of the transformation products varied with time according to a subsequent reaction of an intermediate product. Quantum efficiencies were analyzed for mechanistic purposes. As example, sulfamethoxazole was added to effluents from a wastewater treatment plant and irradiated. Phototoxicity and environmental hazard were assessed through quantitative structure-activity relationship computations. In addition, the minimal inhibition concentrations were determined for Pseudomonas fluorescens and Bacillus subtilis. Conclusions for UV-C irradiation as a fourth purification wastewater treatment stage were derived.  相似文献   
316.
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   

317.
Collaborative problem solving has increasingly become important in the face of the complexities in the management of resources, including protected areas. The strategy undertaken by Girringun Aboriginal Corporation in north tropical Queensland, Australia, for developing co-management demonstrates the potential for a problem solving approach involving sequential initiatives, as an alternative to the more familiar negotiated agreements for co-management. Our longitudinal case study focuses on the development of indigenous ranger units as a strategic mechanism for the involvement of traditional owners in managing their country in collaboration with government and other interested parties. This was followed by Australia's first traditional use of marine resources agreement, and development of a multi-jurisdictional, land to sea, indigenous protected area. In using a relationship building approach to develop regional scale co-management, Girringun has been strengthening its capabilities as collaborator and regional service provider, thus, bringing customary decision-making structures into play to 'care for country'. From this evolving process we have identified the key components of a relationship building strategy, 'the pillars of co-management'. This approach includes learning-by-doing, the building of respect and rapport, sorting out responsibilities, practical engagement, and capacity-building.  相似文献   
318.
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   
319.
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   
320.
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   
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