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951.
The status of computer simulation models from around the world for evaluating the possible ecological, environmental, and societal consequences of global change is presented in this paper. In addition, a brief synopsis of the state of the science of these impacts is included. Issues considered include future changes in climate and patterns of land use for societal needs. Models discussed relate to vegetation (e.g. crop), soil, bio-geochemistry, water, and wildlife responses to conventional, forecasted changes in temperature and precipitation. Also described are models of these responses, alone and interactively, to increased CO(2), other air pollutants and UV-B radiation, as the state of the science allows. Further, models of land-use change are included. Additionally, global multiple sector models of environment, natural resources, human population dynamics, economics, energy, and political relations are reviewed for integrated impact assessment. To the extent available, information on computer software and hardware requirements is presented for the various models. The paper concludes with comments about using these technologies as they relate to ecological risk assessment for policy decision analysis. Such an effort is hampered by considerable uncertainties with the output of existing models, because of the uncertainties associated with input data and the definitions of their dose-response relationships. The concluding suggestions point the direction for new developments in modeling and analyses that are needed for the 21st century.  相似文献   
952.
Fostering ecosystem services in urban road corridors is an important challenge for urban planning and governance because residents are often exposed to environmental pressures in these ubiquitous open spaces. We here aim at illustrating multiple ecosystem services that may be underpinned by roadside vegetation. Previous work is broadly scattered in papers from the natural and social sciences and biased by a focus both on regulating services (temperature regulation, air filtration, carbon sequestration) and also on trees. We provide a first synthesis that illustrates (i) the multi-functional capacity of green elements in streetscapes to deliver various ecosystem services; (ii) the relevance of planted and wild-grown herbaceous vegetation as well as trees; and (iii) trade-offs between certain ecosystem services as well as risks related to disservices. Trees and herbaceous road vegetation can mitigate adverse environmental conditions in road corridors, which is particularly important in vulnerable neighborhoods that are undersupplied with green spaces. Enhancing the amenity value of streetscapes might also positively influence public health by promoting physical activity. However, significant knowledge gaps exist, e.g. on the contribution of biodiversity to ecosystem services and on the valuation of green street components by different sociocultural groups. Our synthesis illustrates management options that can support planning and governance approaches toward more livable streetscapes by fostering ecosystem services and counteracting disservices.  相似文献   
953.
Questions of equity, justice, and fairness in the international agricultural adaptation regime have emerged in recent years, prompting interest in regime power dynamics. Here, a three-dimensional conceptual framework of ‘power as domination’ is applied to the UNFCCC adaptation regime. We argue that this ‘power-over’ framing is an important lens through which to view adaptation, a field dominated by ‘power-to’, capacity-based constructs. The framework distinguishes between power-over manifesting through decision-making, agenda setting and preference shaping. Through a literature review we demonstrate that first and second dimension behavioral views of power-over fail to account for the subtle ways in which the interests and preferences of smallholder farmers are unknowingly shaped and restricted within the regime. Potential sources of third dimension preference shaping power are explored in a survey with high-level decision makers involved in National Adaptation Plans (NAP) development in seven countries. The results suggest that several inter-related features of the international agriculture adaptation regime collectively contribute to the shaping of interests and preferences of smallholders: prevailing discourses of uncertainty and the perceived limited capacity of smallholders; the resulting privileged status of ‘expert’ decision makers; the predominance of neoliberal development rationalities; and systemic biases resulting from the nation state as the principle unit of UNFCCC negotiation. These forces lie beyond the explanatory scope of first and second dimensions of power-over and help to explain why stakeholder engagement in adaptation decision making remains superficial in nature and why adaptation responses in agriculture can be considered ‘common and non-differentiated’. We argue for increased awareness of third dimension manifestations and impacts of power in adaptation literature to facilitate the improved participation of marginalized stakeholders in UNFCCC and domestic adaptation decision making forums, to increase the diversity of adaptation options available to smallholders, and ultimately, to improve the attribution of responsibility for adaptation outcomes.  相似文献   
954.
In this study,the effects of soluble readily biodegradable COD (sCOD) and particulate slowly biodegradable COD (pCOD) on anammox process were investigated.The results of the longterm experiment indicated that a low sCOD/N ratio of 0.5 could accelerate the anammox and denitrification activity,to reach as high as 84.9%±2.8% TN removal efficiency.Partial denitrification-anammox (PDN/anammox) and denitrification were proposed as the major pathways for nitrogen removal,accounting for 91.3% and 8.7% o...  相似文献   
955.
Reducing Emissions from Deforestation and forest Degradation (REDD+) is a promising mechanism of payments for ecosystem services with the aim to effectively reduce emissions in an efficient and equitable manner. REDD+ is part of the Paris-agreement reached at the UNFCCC COP21 in December 2015, but questions on whether REDD+ will work and bring multi-benefits are still hotly debated. Moreover, the results and messages from research on REDD+ in different regions are mixed, context-based and fragmented. Here, we employ a survey among REDD+ stakeholders, researchers, and consultants to evaluate the opportunities and challenges of REDD+ for achieving effective, efficient and equitable outcomes and co-benefits (3E+). We substantiate our survey results with a literature review. Results suggest that the challenges in achieving the 3E+ relate to the disproportionality between deforestation drivers and mitigation measures, diverging perceptions of equity among REDD+ stakeholders, complexity of property rights, and fragile willingness of stakeholders to engage in REDD+. If these challenges can be successfully addressed by the involved stakeholder groups, they can be turned into opportunities for realizing REDD+.  相似文献   
956.
Ecosystem services provided by the landscapes of regions and cities are critical to human and environmental health, quality of life, environmental justice, biodiversity and climate mitigation and adaptation. In the Pacific Northwest region of the US, a team led by the University of Washington Green Futures Lab is working to identify, conserve and enhance regionally-significant landscapes and to evaluate their contributions as ecosystem or “open space” services. This paper outlines the goals and planning methods of the ongoing Regional Open Space Strategy for Central Puget Sound (ROSS) project, and the frameworks and processes being developed to evaluate ecosystem and open space services in order to inform and influence local and regional governance structures and decisions.  相似文献   
957.
958.
Fluorinated compounds (FC) are high-global warming potential (GWP) greenhouse gases used and emitted during the manufacture of silicon semiconductor devices. Following the U.S. EPA's PFC Emissions Vintage Model (PEVM), uncontrolled FC emissions are modeled as proportional to total manufactured layer area (TMLA) of silicon. FC emissions of World Semiconductor Council (WSC) charter member countries (Europe, Japan, Korea, Taiwan and the United States), which voluntarily committed in 1999 to lower FC emissions by 2010 to 10% of baseline year emissions, are modeled for the period 1995–2020. For this same period, emissions from Chinese manufacturers under alternative emission reduction scenarios are modeled. If Chinese manufacturers were to adopt a baseline year of 2005 and a reduction target of 10% below baseline year emissions to be achieved by 2020, emissions would be 3.4 MMTCO2eq, comparable to the similarly projected controlled emissions of an average WSC charter member country (=16.3/5 MMTCO2eq) in 2020. The relative stringency of the alternative reduction scenarios considered for China vary between 50 and 95% reduction compared to business as usual (BAU). This is comparable to the stringency of the WSC charter members’ goals for which FC emission reduction technologies are currently available.  相似文献   
959.
We constructed a model to simulate emissions of CO2 from electricity generation in the US and, using the model, we developed 20-year projections of emissions under various regulatory scenarios.  相似文献   
960.
International cooperation and learning may accelerate climate change adaptation and help countries and regions to adapt more effectively and efficiently. Recognizing the importance and opportunities for mutual learning and knowledge transfer, international and supranational organizations, such as the European Commission, have put programmes for international cooperation in place. This paper presents and tests a framework for assessing multi-level learning outcomes of such international cooperation processes and the conditions that produce these outcomes. The framework distinguishes between: (1) group learning by individual process participants; (2) organizational learning by organizations represented in the process; and (3) network and societal learning by actors external to the process. We verify the analytical potential of the framework by comparing learning by six partners in an adaptation-oriented European cooperation project. The project scores rather high on group learning with participants learning from and – to a lesser extent – also with each other. Learning by partner organizations varied and was generally less whereas learning by external actors was very limited. The case study confirms our expectation that learning outcomes are produced by combinations of partner-specific, process-specific and process-external conditions. The presented framework and insights can be used to stimulate learning in and from international cooperation processes.  相似文献   
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