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131.
Corals and coral-associated species are highly vulnerable to the emerging effects of global climate change. The widespread degradation of coral reefs, which will be accelerated by climate change, jeopardizes the goods and services that tropical nations derive from reef ecosystems. However, climate change impacts to reef social–ecological systems can also be bi-directional. For example, some climate impacts, such as storms and sea level rise, can directly impact societies, with repercussions for how they interact with the environment. This study identifies the multiple impact pathways within coral reef social–ecological systems arising from four key climatic drivers: increased sea surface temperature, severe tropical storms, sea level rise and ocean acidification. We develop a novel framework for investigating climate change impacts in social–ecological systems, which helps to highlight the diverse impacts that must be considered in order to develop a more complete understanding of the impacts of climate change, as well as developing appropriate management actions to mitigate climate change impacts on coral reef and people.  相似文献   
132.
Pollution-induced illnesses are caused by toxicants that result from human activity and are often entirely preventable. However, where industrial priorities have undermined responsible governance, exposed populations must reduce their exposure by resorting to voluntary protective measures and demanding emissions abatement. This paper presents a coupled human–environment system model that represents the effects of water pollution on the health and livelihood of a fishing community. The model is motivated by an incident from 1949 to 1968 in Minamata, Japan, where methylmercury effluent from a local factory poisoned fish populations and humans who ate them. We model the critical role of risk perception in driving both social learning and the protective feedbacks against pollution exposure. These feedbacks are undermined in the presence of social misperceptions such as stigmatization of the injured. Through numerical simulation and scenario analysis, we compare our model results with historical datasets from Minamata, and find that the conditions for an ongoing pollution epidemic are highly unlikely without social misperception. We also find trade-offs between human health outcomes, the viability of the polluting industry and the survival of the fishery. We conclude that an understanding of human–environment interactions and misperception effects is highly relevant to the resolution of contemporary pollution problems, and merits further study.  相似文献   
133.
134.
The sustainability of deltas worldwide is under threat due to the consequences of global environmental change (including climate change) and human interventions in deltaic landscapes. Understanding these systems is becoming increasingly important to assess threats to and opportunities for long-term sustainable development. Here, we propose a simplified, yet inclusive social–ecological system (SES)-centered risk and vulnerability framework and a list of indicators proven to be useful in past delta assessments. In total, 236 indicators were identified through a structured review of peer-reviewed literature performed for three globally relevant deltas—the Mekong, the Ganges–Brahmaputra–Meghna and the Amazon. These are meant to serve as a preliminary “library” of potential indicators to be used for future vulnerability assessments. Based on the reviewed studies, we identified disparities in the availability of indicators to populate some of the vulnerability domains of the proposed framework, as comprehensive social–ecological assessments were seldom implemented in the past. Even in assessments explicitly aiming to capture both the social and the ecological system, there were many more indicators for social susceptibility and coping/adaptive capacities as compared to those relevant for characterizing ecosystem susceptibility or robustness. Moreover, there is a lack of multi-hazard approaches accounting for the specific vulnerability profile of sub-delta areas. We advocate for more comprehensive, truly social–ecological assessments which respond to multi-hazard settings and recognize within-delta differences in vulnerability and risk. Such assessments could make use of the proposed framework and list of indicators as a starting point and amend it with new indicators that would allow capturing the complexity as well as the multi-hazard exposure in a typical delta SES.  相似文献   
135.
Some recent funding programmes in Australia on climate adaptation have expected active engagement with farmers in research projects. Based on our direct experience with 30 farmers and their advisors, we list five reasons why it is difficult to gain traction with farmers in discussing the likely impacts of climate change on their farms and the possible adaptation options they should be considering in preparation for a future changed climate. The reasons concern the slow and uncertain trajectory for changes in climate relative to the time horizon for farm decision-making, when set against short-term fluctuations in weather, prices, costs and government policy. Farmers have optimism for ongoing technological progress keeping abreast of any negative impacts of climate on their production. As one moves from incremental to transformational adaptation options, biophysical research has less to offer because decisions become based more on business structure, portfolio management, off-farm investments and geographical diversification. Some farmers also doubt the intentions of climate change researchers and are wary of anything they may have to offer. We propose there is an actionable decision space where agricultural science and economics can contribute to meaningful analysis of impacts and adaptation to climate change by farmers. This will involve emphasising the principles of farm management rather than defining optimal farm plans; the use of scenario planning to explore possible futures in a turbulent environment for farming; a focus on short-term adjustments as a path to longer term adaptation; re-gaining the trust of some farmers towards climate change scientists through better communication strategies; and understanding the linkages between adaptation options and enabling factors and technologies.  相似文献   
136.
This paper presents an innovative, quantitative assessment of pollution avoidance attributable to environmental regulation enforced through integrated licensing, using Ireland's pharmaceutical-manufacturing sector as a case study. Emissions data reported by pharmaceutical installations were aggregated into a pollution trend using an Environmental Emissions Index (EEI) based on Lifecycle Assessment methodologies. Complete sectoral emissions data from 2001 to 2007 were extrapolated back to 1995, based on available data. Production volume data were used to derive a sectoral production index, and determine ‘no-improvement’ emission trends, whilst questionnaire responses from 20 industry representatives were used to quantify the contribution of integrated licensing to emission avoidance relative to these trends. Between 2001 and 2007, there was a 40% absolute reduction in direct pollution from 27 core installations, and 45% pollution avoidance relative to hypothetical ‘no-improvement’ pollution. It was estimated that environmental regulation avoided 20% of ‘no-improvement’ pollution, in addition to 25% avoidance under business-as-usual. For specific emissions, avoidance ranged from 14% and 30 kt a− 1 for CO2 to 88% and 598 t a− 1 for SOx. Between 1995 and 2007, there was a 59% absolute reduction in direct pollution, and 76% pollution avoidance. Pollution avoidance was dominated by reductions in emissions of VOCs, SOx and NOx to air, and emissions of heavy metals to water. Pollution avoidance of 35% was attributed to integrated licensing, ranging from between 8% and 2.9 t a− 1 for phosphorus emissions to water to 49% and 3143 t a− 1 for SOx emissions to air. Environmental regulation enforced through integrated licensing has been the major driver of substantial pollution avoidance achieved by Ireland's pharmaceutical sector — through emission limit values associated with Best Available Techniques, emissions monitoring and reporting requirements, and performance targets specified in environmental management plans. This compliant sector offers a positive, but not necessarily typical, case study of IPPC effectiveness.  相似文献   
137.
Aircraft emissions affect air quality on scales from local to global. More than 20% of the jet fuel used in the U.S. is consumed by military aircraft, and emissions from this source are facing increasingly stringent environmental regulations, so improved methods for quickly and accurately determining emissions from existing and new engines are needed. This paper reports results of a study to advance the methods used for detailed characterization of military aircraft emissions, and provides emission factors for two aircraft: the F-15 fighter and the C-130 cargo plane. The measurements involved outdoor ground-level sampling downstream behind operational military aircraft. This permits rapid change-out of the aircraft so that engines can be tested quickly on operational aircraft. Measurements were made at throttle settings from idle to afterburner using a simple extractive probe in the dilute exhaust. Emission factors determined using this approach agree very well with those from the traditional method of extractive sampling at the exhaust exit. Emission factors are reported for CO2, CO, NO, NOx, and more than 60 hazardous and/or reactive organic gases. Particle size, mass and composition also were measured and are being reported separately. Comparison of the emissions of nine hazardous air pollutants from these two engines with emissions from nine other aircraft engines is discussed.  相似文献   
138.
Relative rate techniques were used to determine k(Cl + CF3CFCFCF3) = (7.27 ± 0.88) × 10?12, k(Cl + CF3CF2CFCF2) = (1.79 ± 0.41) × 10?11, k(OH + CF3CFCFCF3) = (4.82 ± 1.15) × 10?13, and k(OH + CF3CF2CFCF2) = (1.94 ± 0.27) × 10?12 cm3 molecule?1 s?1 in 700 Torr of air or N2 diluent at 296 K. The chlorine atom- and OH radical-initiated oxidation of CF3CFCFCF3 in 700 Torr of air gives CF3C(O)F in molar yields of 196 ± 11 and 218 ± 20%, respectively. Chlorine atom-initiated oxidation of CF3CF2CFCF2 gives molar yields of 97 ± 9% CF3CF2C(O)F and 97 ± 9% COF2. OH radical-initiated oxidation of CF3CF2CFCF2 gives molar yields of 110 ± 15% CF3CF2C(O)F and 99 ± 8% COF2. The atmospheric fate of CF3CF2C(O)F and CF3C(O)F is hydrolysis to give CF3CF2C(O)OH and CF3C(O)OH. The atmospheric lifetimes of CF3CFCFCF3 and CF3CF2CFCF2 are determined by reaction with OH radicals and are approximately 24 and 6 days, respectively. The contribution of CF3CFCFCF3 and CF3CF2CFCF2 to radiative forcing of climate change will be negligible.  相似文献   
139.
Following the intent of the National Environmental Policy Act of 1969, many states have adopted policies and procedures directing state agencies and local government units to evaluate the potential environmental impacts of development projects prior to their undertaking. In contrast to a rich literature on federal requirements, current understanding of state environmental review is narrowly focused and outdated. This paper seeks to provide information on the landscape of state environmental review policy frameworks. The paper identifies 37 states with formal environmental review requirements through a document review of state statutes, administrative rules and agency-prepared materials, and confirms this finding through a survey of state administrators. A two-tier classification is used to distinguish states based on the approach taken to address environmental review needs and the scope and depth of relevant policies and procedures implemented. This paper also provides a discussion of policy and programme attributes that may contribute to effective practice, and of the potential for adopting relevant legislation in states where environmental review is currently lacking.  相似文献   
140.
With increasing environmental challenges confronting our planet, colleges and universities are trying different approaches for minimizing their adverse environmental impacts. Among the approaches being used to revitalize campus sustainability efforts, new waste management strategies have included attempts to improve campus-recycling programs. This paper presents select findings from a comprehensive study at a large, Tier I university aimed at, among other things, informing university administration and decision makers working on the planning and implementation of a new campus-wide recycling facility and program. The researchers used a mixed-method approach to help them develop an understanding of the campus community's (1) perceived barriers to recycling, (2) recycling knowledge, (3) program preferences, and (4) environmental attitudes. The results from a web-based survey (n = 3896, RR1 = 24.9%) suggest, communication efforts for recycling programming should focus more on messages concerning what, how, and where to recycle rather than messages on why to recycle. Furthermore, the results suggest recycling-related publicity approaches should differentiate their mode and content for different segments of the community.  相似文献   
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