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61.
Ross S. Lunetta Richard G. Greene John G. Lyon 《Journal of the American Water Resources Association》2005,41(5):1129-1147
This study quantified nonpoint source nitrogen (NPS‐N) sources and sinks across the 14,582 km2 Neuse River Basin (NRB) located in North Carolina, to provide tabular data summaries and graphic overlay products to support the development of management approaches to best achieve established N reduction goals. First, a remote sensor derived, land cover classification was performed to support modeling needs. Modeling efforts included the development of a mass balance model to quantify potential N sources and sinks, followed by a precipitation event driven hydrologic model to effectively transport excess N across the landscape to individual stream reaches to support subsequent labeling of transported N values corresponding to source origin. Results indicated that agricultural land contributed 55 percent of the total annual NPS‐N loadings, followed by forested land at 23 percent (background), and urban areas at 21 percent. Average annual N source contributions were quantified for agricultural (1.4 kg/ha), urban (1.2 kg/ha), and forested cover types (0.5 kg/ha). Nonpoint source‐N contributions were greatest during the winter (40 percent), followed by spring (32 percent), summer (28 percent), and fall (0.3 percent). Seasonal total N loadings shifted from urban dominated and forest dominated sources during the winter, to agricultural sources in the spring and summer. A quantitative assessment of the significant NRB land use activities indicated that high (greater than 70 percent impervious) and medium (greater than 35 percent impervious) density urban development were the greatest contributors of NPS‐N on a unit area basis (1.9 and 1.6 kg/ha/yr, respectively), followed by row crops and pasture/hay cover types (1.4 kg/ha/yr). 相似文献
62.
Marlene Roellig Laura M. E. Sutcliffe Marek Sammul Henrik von Wehrden Jens Newig Joern Fischer 《Ambio》2016,45(2):185-195
Wood-pastures are associated with high cultural and biodiversity values in Europe. However, due to their relatively low productivity, large areas of wood-pastures have been lost over the last century. In some areas, incentive schemes have been developed to revive wood-pastures. We investigated the effects of one such scheme in western Estonia. We compared the structure of grazed wood-pastures (old and restored) to those of abandoned wood-pastures and ungrazed forest stands to explore the effects of management, and conducted interviews with 24 farmers to investigate their motivations to carry out the management. We found a positive influence of active management on the semi-open structure of wood-pastures. Financial support was vital for management, but personal values related to tradition also played an important role. The interviewees differed widely in their range of motivations, suggesting that other strategies in addition to financial incentives would further improve the management of wood-pastures in the region.
Electronic supplementary material
The online version of this article (doi:10.1007/s13280-015-0719-8) contains supplementary material, which is available to authorized users. 相似文献63.
64.
Krista Harper Catherine Sands Diego Angarita Horowitz Molly Totman Monica Maitín Jonell Sostre Rosado 《Local Environment》2017,22(7):791-808
How do youth learn through participation in efforts to study and change the school food system? Through our participatory youth action research (YPAR) project, we move beyond the “youth as consumer” frame to a food justice youth development (FJYD) approach. We track how a group of youth learned about food and the public policy process through their efforts to transform their own school food systems by conducting a participatory evaluation of farm-to-school efforts in collaboration with university and community partners. We used the Photovoice research method, placing cameras in the hands of young people so that they themselves could document and discuss their concerns and perspectives. The research was designed to gain insight about youths’ knowledge of food, health, and community food systems. Drawing upon the youth group’s insights, we build a framework for building critical consciousness through FJYD. 相似文献
65.
Michael J. Manfredo Jeremy T. Bruskotter Tara L. Teel David Fulton Shalom H. Schwartz Robert Arlinghaus Shigehiro Oishi Ayse K. Uskul Kent Redford Shinobu Kitayama Leeann Sullivan 《Conservation biology》2017,31(4):772-780
The hope for creating widespread change in social values has endured among conservation professionals since early calls by Aldo Leopold for a “land ethic.” However, there has been little serious attention in conservation to the fields of investigation that address values, how they are formed, and how they change. We introduce a social–ecological systems conceptual approach in which values are seen not only as motivational goals people hold but also as ideas that are deeply embedded in society's material culture, collective behaviors, traditions, and institutions. Values define and bind groups, organizations, and societies; serve an adaptive role; and are typically stable across generations. When abrupt value changes occur, they are in response to substantial alterations in the social–ecological context. Such changes build on prior value structures and do not result in complete replacement. Given this understanding of values, we conclude that deliberate efforts to orchestrate value shifts for conservation are unlikely to be effective. Instead, there is an urgent need for research on values with a multilevel and dynamic view that can inform innovative conservation strategies for working within existing value structures. New directions facilitated by a systems approach will enhance understanding of the role values play in shaping conservation challenges and improve management of the human component of conservation. 相似文献
66.
Understanding local community attitudes toward industrial development in the Great Barrier Reef region World Heritage Area: are environmental impacts perceived to overshadow economic benefits? 下载免费PDF全文
Claudia F. Benham 《Natural resources forum》2017,41(1):42-54
Conflicts between industrial development and environmental conservation can be particularly acute when such development occurs in the vicinity of World Heritage sites. A key example is the Great Barrier Reef World Heritage Area (GBRWHA) in northeastern Australia, where a 2012 review by the World Heritage Council found that rapid port development inshore of the coral reef posed significant risks to local marine ecosystems. Such instances pose pressing challenges for decision‐makers seeking to manage World Heritage sites for multiple values and needs, including those of key stakeholder groups, such as local communities. There is increasingly a societal expectation that public decision‐making takes into account local views and priorities, and that companies seek a ‘social license to operate’. This research explored local community attitudes toward port development associated with the export of liquefied natural gas (LNG) and coal through the GBRWHA. Using data drawn from a survey and interviews, the research examined how a range of geographical factors, including proximity to gas infrastructure and the perceived impacts and risks of development to the local community, economy and environment shape community perceptions of the industry. Findings suggest that local attitudes toward gas and coal terminal development inshore of the GBRWHA are shaped predominantly by community perceptions of environmental impacts and risks associated with such infrastructure, in contrast to a broader public narrative that focuses largely on economic benefits. A complex combination of other factors, including social impacts, personal environmental values, community trust in industry, and equity in decision‐making and distribution of the risks and benefits of industrial development also contribute. Placed in a broader, global context, the findings have important implications for public decision‐making processes in Australia and elsewhere as they suggest that, for local communities, the perceived impacts of gas development on the environment may overshadow the benefits of industry. 相似文献
67.
Developing an interdisciplinary and cross‐sectoral community of practice in the domain of forests and livelihoods 下载免费PDF全文
Cristy Watkins Jennifer Zavaleta Sarah Wilson Scott Francisco 《Conservation biology》2018,32(1):60-71
Although significant resources are being spent researching and fostering the relationship between forests and livelihoods to promote mutually beneficial outcomes, critical gaps in understanding persist. A core reason for such gaps is that researchers, practitioners, and policy makers lack the structured space to interact and collaborate, which is essential for effective, interdisciplinary research, practice, and evaluation. Thus, scientific findings, policy recommendations, and measured outcomes have not always been synthesized into deep, systemic understanding; learning from practice and implementation does not easily find its way into scientific analyses, and science often fails to influence policy. Communities of practice (CofPs) are dynamic sociocultural systems that bring people together to share and create knowledge around a common topic of interest. They offer participants a space and structure within which to develop new, systemic approaches to multidimensional problems on a common theme. Uniquely informed by a systems‐thinking perspective and drawing from the scientific and gray literatures and in‐depth interviews with representatives of established CofPs in the natural resource management and development domain, we argue that a well‐designed and adequately funded CofP can facilitate interdisciplinary and cross‐sectoral relationships and knowledge exchange. Well‐designed CofPs integrate a set of core features and processes to enhance individual, collective, and domain outcomes; they set out an initial but evolving purpose, encourage diverse leadership, and promote collective‐identity development. Funding facilitates effective communication strategies (e.g., in person meetings). We urge our colleagues across sectors and disciplines to take advantage of CofPs to advance the domain of forests and livelihoods. 相似文献
68.
Luca Coscieme Federico M. Pulselli Simone Bastianoni Christopher D. Elvidge Sharolyn Anderson Paul C. Sutton 《Ambio》2014,43(7):969-979
Night-time satellite imagery enables the measurement, visualization, and mapping of energy consumption in an area. In this paper, an index of the “sum of lights” as observed by night-time satellite imagery within national boundaries is compared with the emergy of the nations. Emergy is a measure of the solar energy equivalent used, directly or indirectly, to support the processes that characterize the economic activity in a country. Emergy has renewable and non-renewable components. Our results show that the non-renewable component of national emergy use is positively correlated with night-time satellite imagery. This relationship can be used to produce emergy density maps which enable the incorporation of spatially explicit representations of emergy in geographic information systems. The region of Abruzzo (Italy) is used to demonstrate this relationship as a spatially disaggregate case. 相似文献
69.
Michael Duijn Arwin van Buuren Magnus Sparrevik Adriaan Slob Gerald Jan Ellen Amy Oen 《Journal of Environmental Planning and Management》2016,59(5):927-947
This study aims at describing, analyzing and evaluating the relation between management styles and process dynamics of a complex planning process confronted with unexpected dynamics. The development of an aquatic disposal site for dredged contaminated sediments in Oslo was managed by a project management style focused on timely and cost-effective implementation. Coupling the remediation project with another infrastructural project and the actual construction of the site led to unexpected dynamics in terms of resistance and controversy. Project management had difficulties in adjusting its style accordingly, resulting in even more delay and resistance. Managing complex planning projects requires a style suitable to the characteristics of the project and the capability of adjusting it to changing circumstances. The paper concludes with some explanations why it is difficult to change management styles in complex planning and implementation processes and complexity-embracing approaches to deal with this. 相似文献
70.
For more than 30 years, multiple research groups have worked on the automation of hazard and operability (HAZOP) studies, or more specifically on the hazard identification process. So far, very few of these approaches have been used in the chemical process industry. Automatic hazard identification is a knowledge-intensive process that demands high standards with regard to the way in which knowledge is stored and made available. There are various suitable approaches to the qualitative modeling of processes and plants, which are the foundation for reasoning systems that are used for the identification of hazards. Additionally, there are quantitative methods that are based on process simulations and can be used to identify potential hazards. The investigation of the state of research demonstrates that there are sophisticated technologies for automated systems that include powerful reasoning techniques. The benefits and shortcomings of existing technologies are discussed with regard to their industrial applicability. Often, the quality of the necessary specific and generic knowledge is not sufficient to detect potential hazardous events and operational malfunctions. Computer-aided HAZOP systems should be integrated with computer-aided design- or process simulation software using common data models based on the digital representation of the process plant. In order to be used by HAZOP practitioners automated systems need to be comprehensive, serve as specialized decision support systems, and be tested and evaluated using round robin tests. 相似文献