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51.
Water allocation systems are challenged by hydrologic droughts, which reduce available water supplies and can adversely affect human and environmental systems. To address this problem, drought management mechanisms have been instituted in jurisdictions around the world. Historically, these mechanisms have involved a crisis management or reactive approach. An important trend during the past decade in places such as the United States has been a shift to a more proactive approach, emphasizing drought preparedness and local involvement. Unfortunately, local capacity for drought planning is highly variable, with some local governments and organizations proving to be more capable than others of taking on new responsibilities. This paper reports on a study of drought planning and water allocation in the State of Minnesota. Factors facilitating and constraining local capacity for drought planning were identified using in-depth key informant interviews with state officials and members of two small Minnesota cities, combined with an analysis of pertinent documentation. A key factor contributing to the effectiveness of Minnesota's system is a water allocation system with explicit priorities during shortages, and provisions for restrictions. At the same time, the requirement that water suppliers create Public Water Supply Emergency Conservation Plans (PWSECP) clarifies the roles and responsibilities of key local actors. Unfortunately, the research revealed that mandated PWSECP are not always implemented, and that awareness of drought and drought planning measures in general may be poor at the local level. From the perspective of the two cities evaluated, factors that contributed to local capacity included sound financial and human resources, and (in some cases) effective vertical and horizontal linkages. This analysis of experiences in Minnesota highlights problems that can occur when senior governments establish policy frameworks that increase responsibilities at the local level without also addressing local capacity. 相似文献
52.
We studied the effects of spatial and temporal timber harvesting constraints on competing objectives of sustaining wildlife habitat supply and meeting timber harvest objectives in a boreal mixedwood forest. A hierarchical modeling approach was taken, where strategic and tactical level models were used to project blocking and scheduling of harvest blocks. Harvest block size and proximity, together with short- and long-term temporal constraints, were adjusted in a factorial manner to allow creation of response–surface models. A new measure of the habitat mosaic was defined to describe the emergent pattern of habitat across the landscape. These models, together with multiple linear regression, were used to provide insight on convergence or divergence between spatial objectives. For example, green-up delay (defined as time required before a harvest block adjacent to a previously logged block can be scheduled for harvest) had an adverse effect on the amount of annual harvest area that could be allocated and blocked spatially, and habitat supply responded in an opposite direction to that of wood supply, where caribou, moose wintering, and marten habitat supply increased when harvest blocks were further apart, maximum block size smaller, and both a green-up delay and mesoscale stratification were applied. Although there was no solution space free of conflicts, the analysis suggests that application of the mesoscale stratification, together with a diversity of harvest block sizes and a between-harvest block proximity of 250 m, will perform relatively well with respect to wood supply objectives, and at the same time create a less fragmented landscape that better reflects natural forest patterns. 相似文献
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54.
Evaluation of the effect of a cover layer on radon exhalation from uranium mill tailings: transient radon flux analysis 总被引:1,自引:0,他引:1
An experimental study concerning the transport of 222Rn in uranium mill tailings (UMTs) and in the cover layer was launched in 1997 with the participation of the French uranium mining company (COGEMA). Evaluation of the cover layer's effectiveness in reducing 222Rn flux emanating from UMTs was one of its objectives. In the first phase, the 222Rn flux densities were measured regularly on a UMT layer. In the second phase, the UMT was covered with a one-meter layer of compacted material consisting of crushed waste rock derived from mining activities. Radon-222 flux was then measured at the surface of this cover layer. Observations were compared with radon flux calculated using TRACI, a model for vertical water and gas flow and radon transport. The results show that the calculations bear a fair resemblance to the observations in both cases. They also show that the effectiveness of the cover layer calculated with TRACI, using the thickness and textural properties of the cover material, is very close to the measured effectiveness. 相似文献
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Derek Armitage Rob C. de Lo? Michelle Morris Tom W. D. Edwards Andrea K. Gerlak Roland I. Hall Dave Huitema Ray Ison David Livingstone Glen MacDonald Naho Mirumachi Ryan Plummer Brent B. Wolfe 《Ambio》2015,44(5):353-366
In this policy perspective, we outline several conditions to support effective science–policy interaction, with a particular emphasis on improving water governance in transboundary basins. Key conditions include (1) recognizing that science is a crucial but bounded input into water resource decision-making processes; (2) establishing conditions for collaboration and shared commitment among actors; (3) understanding that social or group-learning processes linked to science–policy interaction are enhanced through greater collaboration; (4) accepting that the collaborative production of knowledge about hydrological issues and associated socioeconomic change and institutional responses is essential to build legitimate decision-making processes; and (5) engaging boundary organizations and informal networks of scientists, policy makers, and civil society. We elaborate on these conditions with a diverse set of international examples drawn from a synthesis of our collective experiences in assessing the opportunities and constraints (including the role of power relations) related to governance for water in transboundary settings. 相似文献
57.
Global climate change will have a strong impact on Nigeria, particularly on agricultural production and associated livelihoods. Although there is a growing scientific consensus about the impact of climate change, efforts so far in Nigeria to deal with these impacts are still rudimentary and not properly coordinated. There is little evidence of any pragmatic approach towards tracking climate change in order to develop an evidence base on which to formulate national adaptation strategies. Although Nigeria is not alone in this regard, the paper asserts that National Climate Change Adaptation Strategy could help address this situation by guiding the integration of climate change adaptation into government policies, strategies, and programs, with particular focus on the most vulnerable groups and the agricultural sectors. There is an urgent need to adopt abatement strategies that will provide economic incentives to reduce the risk from disasters, such as developing agricultural practices that are more resilient to a changing climate. 相似文献
58.
Marie Claire Brisbois Rob C. de Loë 《Journal of Environmental Planning and Management》2017,60(5):883-900
Natural resource industries are increasingly significant actors in environmental decision-making. Possessing vast institutional and technical capacity, firms have an important role to play in ‘new’ governance strategies such as collaboration. These strategies are often based upon assumptions of equitable influence. This paper investigates the nature of resource industry participation in collaborative water governance in Canada, and the potential consequences of that participation as investigated using power theory. The study used comparative cases to reveal that resource industries are able to shape collaboration, and the issues collaborated upon, at multiple analytical levels both internal and external to the collaborative process in ways not available to other actors. Analysis also revealed that resource industry participation in collaboration did not reflect a commitment to engage in shared learning and the reexamination of values and interests as presupposed by collaborative theory. Collaboration is thus challenged in producing equitable, representative outcomes when resource industries participate. 相似文献
59.
Forest fires and adaptation options in Europe 总被引:1,自引:0,他引:1
Nikolay Khabarov Andrey Krasovskii Michael Obersteiner Rob Swart Alessandro Dosio Jesús San-Miguel-Ayanz Tracy Durrant Andrea Camia Mirco Migliavacca 《Regional Environmental Change》2016,16(1):21-30
This paper presents a quantitative assessment of adaptation options in the context of forest fires in Europe under projected climate change. A standalone fire model (SFM) based on a state-of-the-art large-scale forest fire modelling algorithm is used to explore fuel removal through prescribed burnings and improved fire suppression as adaptation options. The climate change projections are provided by three climate models reflecting the SRES A2 scenario. The SFM’s modelled burned areas for selected test countries in Europe show satisfying agreement with observed data coming from two different sources (European Forest Fire Information System and Global Fire Emissions Database). Our estimation of the potential increase in burned areas in Europe under “no adaptation” scenario is about 200 % by 2090 (compared with 2000–2008). The application of prescribed burnings has the potential to keep that increase below 50 %. Improvements in fire suppression might reduce this impact even further, e.g. boosting the probability of putting out a fire within a day by 10 % would result in about a 30 % decrease in annual burned areas. By taking more adaptation options into consideration, such as using agricultural fields as fire breaks, behavioural changes, and long-term options, burned areas can be potentially reduced further than projected in our analysis. 相似文献
60.
Mapping epistemic cultures and learning potential of participants in citizen science projects 下载免费PDF全文
Priya Vallabh Heila Lotz‐Sisitka Rob O'Donoghue Ingrid Schudel 《Conservation biology》2016,30(3):540-549
The ever‐widening scope and range of global change and interconnected systemic risks arising from people–environment relationships (social‐ecological risks) appears to be increasing concern among, and involvement of, citizens in an increasingly diversified number of citizen science projects responding to these risks. We examined the relationship between epistemic cultures in citizen science projects and learning potential related to matters of concern. We then developed a typology of purposes and a citizen science epistemic‐cultures heuristic and mapped 56 projects in southern Africa using this framework. The purpose typology represents the range of knowledge‐production purposes, ranging from laboratory science to social learning, whereas the epistemic‐cultures typology is a relational representation of scientist and citizen participation and their approach to knowledge production. Results showed an iterative relationship between matters of fact and matters of concern across the projects; the nexus of citizens’ engagement in knowledge‐production activities varied. The knowledge‐production purposes informed and shaped the epistemic cultures of all the sampled citizen science projects, which in turn influenced the potential for learning within each project. Through a historical review of 3 phases in a long‐term river health‐monitoring project, we found that it is possible to evolve the learning curve of citizen science projects. This evolution involved the development of scientific water monitoring tools, the parallel development of pedagogic practices supporting monitoring activities, and situated engagement around matters of concern within social activism leading to learning‐led change. We conclude that such evolutionary processes serve to increase potential for learning and are necessary if citizen science is to contribute to wider restructuring of the epistemic culture of science under conditions of expanding social‐ecological risk. 相似文献