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111.
The spatial integrity of a habitat or landscape is determined by the occurrence of habitat fragments and of perforations inside them. A landscape is said to have less spatial integrity with increasing numbers of fragments and perforations. The Euler number (ε) is a numerical measure of spatial integrity, based upon the difference |n f n p | between the number of fragments (n f ) and the number of perforations (n p ). In this contribution, ε is evaluated, and an improvement is presented as a new index ε*, which is a combination of two metrics (ε i , ε d ) based on n f and n p . The term ε i quantifies the intensity of perforation and/or fragmentation. The term ε d measures the extent to which fragmentation predominates perforation, and vice versa. The intensity and dominance measures are combined into an Euclidean distance measure, generating the new ensemble value ε*, calculated as ε*= (n f +n p )−1√[1 +n f 2]. Use, sensitivity, and application of ε*, ε i , and ε d are illustrated using percolation maps. Application of the new metrics by environmental scientists is encouraged because (1) no negative values can be generated with ε*, ε i , and ε d ; (2) the range of ε*, ε i , and ε d is fixed; (3) process dominance and intensity are both assessed; (4) ε*, ε i , and ε d are easy to calculate and to interpret; and (5) ε* is not only based upon |n f n p |, as ε is. Guidelines for practical use by means of a biplot of ε i and ε d are given.  相似文献   
112.
Optimum natural resource management and biodiversity conservation are desirable goals. These, however, often exclude each other, since maximum economic benefits have promoted drastic reductions in biodiversity throughout the world. This dilemma confronts local stakeholders, who usually go for maximizing economic inputs, whereas other social (e.g., academic) sectors are favor conservation practices. In this paper we describe the way two scientific approaches—landscape and participatory research—were used to develop sound and durable land use scenarios. These two approaches included expert knowledge of both social and environmental conditions in indigenous communities. Our major emphasis was given to detect spatially explicit land use scenarios and capacity building in order to construct a decision support system operated by stakeholders of the Comunidad Indigena de Nuevo San Juan Parangaricutiro in Mexico. The system for decision-making was fed with data from inventories of both abiotic and biotic biodiversity components. All research, implementation, and monitoring activities were conducted in close collaboration with members of the indigenous community. As a major result we obtained a number of forest alternative uses that favor emerging markets and make this indigenous community less dependent on a single market. Furthermore, skilled members of the community are now running the automated system for decision-making. In conclusion, our results were better expressed as products with direct benefits in local livelihoods rather than pure academic outputs.  相似文献   
113.
Radioactive contamination of agricultural land may necessitate long-term changes in food production systems, through application of selected countermeasures, in order to reduce the accumulation of radionuclides in food. We quantified the impact of selected countermeasures on habitat diversity, using the hypothetical case of two agricultural areas in Finland. The management scenarios studied were conversions from grassland to cereal production and from grassland and crop production to afforestation. The two study sites differed with respect to present agricultural production: one being predominantly cereal production and seminatural grasslands, while the other was dominated by intensive grass and dairy production. Some of the management scenarios are expected to affect landscape structures and habitat diversity. These potential changes were assessed using a spatial pattern analysis program in connection with geographic information systems. The studied landscape changes resulted in a more monotonous landscape structure compared to the present management, by increasing the mean habitat patch size, reducing the total habitat edge length and reducing the overall habitat diversity calculated by the Shannon diversity index. The degree of change was dependent on the present agricultural management practice in the case study sites. Where dairy production was predominant, the landscape structure changes were mostly due to conversion of intensive pastures and grasslands to cereal production. In the area dominated by cereal production and seminatural grasslands, the greatest predicted impacts resulted from afforestation of meadows and pastures. The studied management changes are predicted to reduce biodiversity at the species level as well as diminishing species-rich habitats. This study has predicted prominent side effects in habitat diversity resulting from application of management scenarios. These potential long-term impacts should be considered by decision-makers when planning future strategies in the event of radionuclide deposition.  相似文献   
114.
Assessing Landscape Health: A Case Study from Northeastern Italy   总被引:17,自引:0,他引:17  
This article investigates the concept of biophysical landscape health for what are termed “highly governed landscapes.” It proposes a definition of landscape health along with a preliminary diagnostic model and methods. The idea of landscape health derives from the emerging integrative science of ecosystem health, which seeks to diagnose ecosystem condition as humans diagnose human health. Highly governed landscapes, such as the reclaimed areas of coastal northeastern Italy, are landscapes that have been subject to even greater degrees of human manipulation than normal cultural landscapes. These highly altered landscapes are not easily served by existing environmental paradigms and concepts of health are seen to have numerous advantages. This paper condenses a broader investigation of landscape health into three main sections. A brief review of the literature is followed by a case study, which details two different phases of landscape transformation in the Lower Piave area of northeastern Italy. A definition and general parameters of biophysical landscape health are then presented after this background stage. Some key parameters of biophysical health include absence of distress and risk factors, sustainability, biodiversity, resilience, and balance. For certain parameters, a preliminary landscape health diagnostic framework is presented that includes potential diagnostic methods and thresholds based on findings from this case study. At the paper's conclusion, a summary diagnostic model is presented, which suggests a process needed to implement landscape health assessment into practice.  相似文献   
115.
Infectious disease surveillance has become an international top priority due to the perceived risk of bioterrorism. This is driving the improvement of real-time geo-spatial surveillance systems for monitoring disease indicators, which is expected to have many benefits beyond detecting a bioterror event. West Nile Virus surveillance in New York State (USA) is highlighted as a working system that uses dead American Crows (Corvus brachyrhynchos) to prospectively indicate viral activity prior to human onset. A cross-disciplinary review is then presented to argue that this system, and infectious disease surveillance in general, can be improved by complementing spatial cluster detection of an outcome variable with predictive “risk mapping” that incorporates spatiotemporal data on the environment, climate and human population through the flexible class of generalized linear mixed models.
Glen D. JohnsonEmail:
  相似文献   
116.
Fifty years have elapsed since the first publication of Ambio. Throughout this period, fundamental changes have occurred in societal attitudes to biodiversity conservation. Ambio has published numerous papers that have aligned with these new approaches. High citations numbers suggest that Ambio papers have had a significant impact on conservation strategies. We review these publications and find that they align well with changed societal perspectives on biodiversity. Ambio papers have called for greater contributions of local and indigenous peoples and for conservation in multi-functional landscapes. The 1992 Convention on Biological Diversity built on these principles. Negotiations are now underway for a post-2020 framework for biodiversity. Ambio papers have argued for a stronger scientific basis for conservation and for the need to adapt to changing conditions and to the rich diversity of societal preferences for conservation. International processes favor simple, generalizable approaches to conservation but we call for recognition of the diversity of ecological and human conditions in which conservation occurs. There is a need to build capacity to support a diversity of conservation approaches that are adapted to changing local conditions and to the priorities of diverse human societies.  相似文献   
117.
The natural range of variation of ecosystems provides reference conditions for sustainable management and biodiversity conservation. We review how the understanding of natural reference conditions of boreal forests in northern Europe has changed from earlier perceptions of even-aged dynamics driven by stand-replacing disturbances towards current understanding highlighting the role of non-stand-replacing disturbances and the resultant complex forest dynamics and structures. We show how earlier views and conceptual models of forest disturbance dynamics, including the influential ASIO model, provide estimates of reference conditions that are outside the natural range of variation. Based on a research synthesis, we present a revised forest reference model incorporating the observed complexity of ecosystem dynamics and the prevalence of old forests. Finally, we outline a management model and demonstrate its use in forest ecosystem management and show how regional conservation area needs can be estimated. We conclude that attaining favourable conservation status in northern Europe’s boreal forests requires increasing emphasis on ecosystem management and conservation for old forest characteristics.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01444-3) contains supplementary material, which is available to authorized users.  相似文献   
118.
Functional agrobiodiversity (FAB) has severely declined during the last decades. Current efforts to reinforce FAB are mainly focused on single-actor, parcel-based measures, whereas multi-actor landscape approaches are supposed to be more effective. In this paper, we propose a social–ecological framework that structures how different land users at both the parcel and landscape level interact with FAB as a natural resource. Furthermore, we introduce 1 m2 FAB gardens as an interactive multipurpose measurement tool to gather data on ecosystem services in collaboration with land users. The presented action research approach provides new insights on motivations and interests of different land users in FAB and how knowledge exchange can result in a higher motivation to invest in FAB. Using a case study in Flanders, we illustrate the FAB-garden concept and highlight its strengths and necessary considerations to properly complement other research approaches in this social–ecological system.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01382-0) contains supplementary material, which is available to authorized users.  相似文献   
119.
Academics and policy makers seeking to deconstruct landscape face major challenges conceptually, methodologically and institutionally. The meaning(s), identity(ies) and management of landscape are controversial and contested. The European Landscape Convention provides an opportunity for action and change set within new governance agendas addressing interdisciplinarity and spatial planning. This paper critically reviews the complex web of conceptual and methodological frameworks that characterise landscape planning and management and then focuses on emerging landscape governance in Scotland within a mixed method approach involving policy analyses, semi-structured interviews and best practice case studies. Using Dower's (2008) criteria from the Articles of the European Landscape Convention, the results show that whilst some progress has been made in landscape policy and practice, largely through the actions of key individuals and champions, there are significant institutional hurdles and resource limitations to overcome. The need to mainstream positive landscape outcomes requires a significant culture change where a one-size-fits-all approach does not work.  相似文献   
120.
Participatory processes in general and also in relation to managing landscape issues are gathering importance mostly due to arguments surrounding legitimacy and effectiveness in decision-making. The main aim of this research, based on a transaction costs perspective, is to present an integrated analytical framework in order to determine individual efforts (time, money), benefits and risks of participants in landscape co-management processes. Furthermore a reflection on the analytical approach developed and arising lessons to be learned for landscape co-management are presented. In the analytical framework benefit-components comprise of factors such as 'contributing to landscape maintenance/development and nature protection', 'representing one's interest group', 'co-deciding on relevant topics', 'providing and broadening one's knowledge' and 'building networks'. The risks of participation are related to a lack of information and agreements, missing support and actual decision-making power. The analytical framework is applied to two case studies in Austria: an EU LIFE-Nature project and a Cultural Landscape Project of the Provincial Government of Lower Austria. Analysis of the effort-benefit-relations provides an indication for a more effective design of co-management. Although the processes are rated as quite adequate, there is a low willingness of participants to commit additional time to co-management processes. In contrast to the Cultural Landscape Project, in the LIFE-Nature project, professionally involved persons participate next to partly and full volunteers. These uneven conditions of participation and an unfair distribution of transaction costs, jeopardize the promising chances co-management bears for landscape governance.  相似文献   
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