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771.
Case studies of scenario analysis for adaptive management of natural resource and infrastructure systems 总被引:1,自引:1,他引:0
Michelle C. Hamilton Shital A. Thekdi Elisabeth M. Jenicek Russell S. Harmon Michael E. Goodsite Michael P. Case Christopher W. Karvetski James H. Lambert 《The Environmentalist》2013,33(1):89-103
Management of natural resources and infrastructure systems for sustainability is complicated by uncertainties in the human and natural environment. Moreover, decisions are further complicated by contradictory views, values, and concerns that are rarely made explicit. Scenario analysis can play a major role in addressing the challenges of sustainability management, especially the core question of how to scan the future in a structured, integrated, participatory, and policy-relevant manner. In a context of systems engineering, scenario analysis can provide an integrated and timely understanding of emergent conditions and help to avoid regret and belated action. The purpose of this paper is to present several case studies in natural resources and infrastructure systems management where scenario analysis has been used to aide decision making under uncertainty. The case studies include several resource and infrastructure systems: (1) water resources (2) land-use corridors (3) energy infrastructure, and (4) coastal climate change adaptation. The case studies emphasize a participatory approach, where scenario analysis becomes a means of incorporating diverse stakeholder concerns and experience. This approach to scenario analysis provides insight into both high-performing and robust initiatives/policies, and, perhaps more importantly, influential scenarios. Identifying the scenarios that are most influential to policy making helps to direct further investigative analysis, modeling, and data-collection efforts to support the learning process that is emphasized in adaptive management. 相似文献
772.
Abstract While US climate change mitigation policy has stalled at the national level, local and regional actors are increasingly taking progressive steps to reduce their greenhouse gas emissions. Universities are poised to play a key role in this grassroots effort by targeting their own emissions and by working with other local actors to develop climate change mitigation programmes. Researchers at the Pennsylvania State University have collaborated with university administrators and personnel to inventory campus emissions and develop mitigation strategies. In addition, they have facilitated a stakeholder-driven climate change mitigation project in one Pennsylvania county and started an ongoing service-learning project aimed at reducing emissions in another county. These campus and community outreach initiatives demonstrate that university-based mitigation action may simultaneously achieve tangible local benefits and develop solutions to broader challenges facing local climate change mitigation efforts. Outcomes include improved tools and protocols for measuring and reducing local emissions, lessons learned about service-learning approaches to climate change mitigation, and methods for creating climate change governance networks involving universities, local governments and community stakeholders. 相似文献
773.
774.
Baumgardner RE Isil SS Lavery TF Rogers CM Mohnen VA 《Journal of the Air & Waste Management Association (1995)》2003,53(3):291-308
Cloud water deposition was estimated at three high-elevation sites in the Appalachian Mountains of the eastern United States (Whiteface Mountain, NY; Whitetop Mountain, VA; and Clingman's Dome, TN) from 1994 through 1999 as part of the Mountain Acid Deposition Program (MADPro). This paper provides a summary of cloud water chemistry, cloud liquid water content, cloud frequency, estimates of cloud water deposition of sulfur and nitrogen species, and estimates of total deposition of sulfur and nitrogen at these sites. Other cloud studies in the Appalachians and their comparison to MADPro are also summarized. Whiteface Mountain exhibited the lowest mean and median concentrations of sulfur and nitrogen ions in cloud water, while Clingman's Dome exhibited the highest mean and median concentrations. This geographic gradient is partly an effect of the different meteorological conditions experienced at northern versus southern sites in addition to the difference in pollution content of air masses reaching the sites. All sites measured seasonal cloud water deposition rates of SO4(2-) greater than 50 kg/ha and NO3(-) rates of greater than 25 kg/ha. These high-elevation sites experienced additional deposition loading of SO4(2-) and NO3(-) on the order of 6-20 times greater compared with lower elevation Clean Air Status and Trends Network (CASTNet) sites. Approximately 80-90% of this extra loading is from cloud deposition. 相似文献
775.
Natural factors and human modifications contribute to the estimated annual loss of 10,200 ha of coastal land in the Mississippi River Deltaic Plain Region of south Louisiana. This paper combines information on regional geology and human-induced habitat alterations to evaluate the relative importance of human and natural factors to marsh loss. Data on marsh area and habitat type for 139 7.5-min quadrangles were calculated from maps based on aerial photographs from 1955/56 and 1978, and data on regional geology obtained from published maps were used to construct multivariate model relating initial marsh area, change in urban and agricultural area, change in canal and spoil area, canal area in 1978, depth of sediment overlying the Prairie terrace, and subdelta age to marsh loss. The model indicated that between 25.0% and 39.0% of the marsh loss that occurred during the 23-year period was related to canal and spoil construction, and between 9.5% and 12.7% was related to urban and agricultural development. These are minimal estimates of loss because they do not include many secondary effects (for example, canal orientation, saltwater intrusion, and eutrophication) that can also result in indirect loss. Depth of sediment, initial marsh area, delta lobe age by 1978 canal and spoil area interaction, and indirect effects not included in the model accounted for remaining marsh loss. 相似文献
776.
Tzay-Rong Jenq Marvin L. Granstrom Shing-Fu Hsueh Christopher G. Uchrin 《Journal of the American Water Resources Association》1984,20(4):511-520
ABSTRACT A linear programming model to assess the cost-effectiveness of appropriate point and nonpoint phosphorus control measures was constructed for Carnegie Lake, an eutrophic lake located in Mercer County, New Jersey. The resultant model was tested for present and future conditions. Feasible solutions were obtained only after significant relaxation of receiving water quality standards. The high levels of point source treatment required to meet the in-stream water quality standards and the mesotrophic loading conditions suggest that a source control solution may not be feasible. 相似文献
777.
Randall A. Kramer Sahat M. H. Simanjuntak Christopher Liese 《Ambio-人类环境杂志》2002,31(4):367-372
东南亚的沿海生态系统正处于来自局部和全球变化增长的压力下.本文研究了印度尼西亚北苏拉威西省米纳哈萨区沿海村庄中的人口迁徒和海洋资源利用情况.原始数据是通过对村庄领导人、重点人群的采访以及600个捕鱼家庭的抽样调查收集的.在过去10年经济增长总量中至少有1/4应归功于人口迁徙.所有渔民团体都报道说近岸渔业生产力正在下降.经济计量学分析被用来研究手工捕鱼部门的周渔获量.人口迁徙状态和社会经济变量看来不产生系统的影响,而渔捞能力(劳动力、渔船及渔具),专业化程度以及村庄地处遥远被认为确实与周渔获量大小有关系. 相似文献
778.
779.
Marvin CH Leppard GG West MM Stern GA Boden AR McCarry BE 《Journal of environmental quality》2004,33(6):2132-2140
To understand contaminant transport in aquatic systems, it is essential to define the physical characteristics of the primary particulate carriers. The distribution of organic pollutants with particle-size class and particle morphology in a freshwater embayment (Hamilton Harbor, western Lake Ontario) was studied using a sequence of novel sample preparation and characterization techniques. Water samples (24 L) were fractionated according to particle-size distribution using differential cascade sedimentation and centrifugation methods. These size fractions were subsequently subjected to a physicochemical characterization using scanning transmission electron microscopy and energy-dispersive spectroscopy to identify flocs and individual colloidal particles in the size range of 1 nm to 1 mm in diameter. Analytical chemical analyses were performed to identify organic contaminants in extracts prepared from particle-size classes, including polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). The contaminant distribution trends were very similar for all compound classes studied; contaminants were primarily associated with fractions containing particles less than 2 mum in diameter. Morphological characterization of these fractions showed the majority of the particulates to be humic fractals. The results of this study show that contaminants in aquatic systems can be preferentially associated with specific types of particle carriers, the characteristics of which can be clearly defined in terms of size and morphology. 相似文献
780.
The Influence of Urban Density and Drainage Infrastructure on the Concentrations and Loads of Pollutants in Small Streams 总被引:14,自引:0,他引:14
Effective water quality management of streams in urbanized basins requires identification of the elements of urbanization that contribute most to pollutant concentrations and loads. Drainage connection (the proportion of impervious area directly connected to streams by pipes or lined drains) is proposed as a variable explaining variance in the generally weak relationships between pollutant concentrations and imperviousness. Fifteen small streams draining independent subbasins east of Melbourne, Australia, were sampled for a suite of water quality variables. Geometric mean concentrations of all variables were calculated separately for baseflow and storm events, and these, together with estimates of runoff derived from a rainfall-runoff model, were used to estimate mean annual loads. Patterns of concentrations among the streams were assessed against patterns of imperviousness, drainage connection, unsealed (unpaved) road density, elevation, longitude (all of which were intercorrelated), septic tank density, and basin area. Baseflow and storm event concentrations of dissolved organic carbon (DOC), filterable reactive phosphorus (FRP), total phosphorus (TP) and ammonium, along with electrical conductivity (EC), all increased with imperviousness and its correlates. Hierarchical partitioning showed that DOC, EC, FRP, and storm event TP were independently correlated with drainage connection more strongly than could be explained by chance. Neither pH nor total suspended solids concentrations were strongly correlated with any basin variable. Oxidized and total nitrogen concentrations were most strongly explained by septic tank density. Loads of all variables were strongly correlated with imperviousness and connection. Priority should be given to low-impact urban design, which primarily involves reducing drainage connection, to minimize urbanization-related pollutant impacts on streams. 相似文献