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91.
Adaptation to climate change has been reviewed in several developed nations, but in none where consideration of the effects of climate change is required by statute and devolved to local government. We examine the role of institutional arrangements, the players operating under them, the barriers and enablers for adaptation decision-making in the developed nation of New Zealand. We examine how the roles and responsibilities between national, regional and local governments influence the ability of local government to deliver long-term flexible responses to changing climate risk. We found that the disciplinary practices of law, engineering and planning, within legal frameworks, result in the use of static mechanisms which create inflexible responses to changing risk. Several enablers are identified that could create greater integration between the different scales of government, including better use of national policy instruments, shared professional experience, standardised information collection and risk assessment methods that address uncertainties. The framing of climate risk as dynamic and changing that differentiates activities over their lifetime, development of mechanisms to fund transitions towards transformational change, are identified as necessary conditions for delivering flexible responses over time.  相似文献   
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Current methods for large-scale vegetation monitoring rely on multispectral remote sensing, which has serious limitation for the detection of vegetation stress. To contribute to the establishment of a generalized spectral approach for vegetation stress detection, this study compares the ability of high-spectral-resolution reflectance (R) and fluorescence (F) foliar measurements to detect vegetation changes associated with common environmental factors affecting plant growth and productivity. To obtain a spectral dataset from a broad range of species and stress conditions, plant material from three experiments was examined, including (i) corn, nitrogen (N) deficiency/excess; (ii) soybean, elevated carbon dioxide, and ozone levels; and (iii) red maple, augmented ultraviolet irradiation. Fluorescence and R spectra (400-800 nm) were measured on the same foliar samples in conjunction with photosynthetic pigments, carbon, and N content. For separation of a wide range of treatment levels, hyperspectral (5-10 nm) R indices were superior compared with F or broadband R indices, with the derivative parameters providing optimal results. For the detection of changes in vegetation physiology, hyperspectral indices can provide a significant improvement over broadband indices. The relationship of treatment levels to R was linear, whereas that to F was curvilinear. Using reflectance measurements, it was not possible to identify the unstressed vegetation condition, which was accomplished in all three experiments using F indices. Large-scale monitoring of vegetation condition and the detection of vegetation stress could be improved by using hyperspectral R and F information, a possible strategy for future remote sensing missions.  相似文献   
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Increasingly, performance measurement is being used to hold federal agencies accountable, represent environmental progress, and evaluate the effectiveness of environmental programs. The need to track measurable outputs has created a tendency to present programmatic progress solely by quantifiable data, despite the inherent complexity of natural resource management. Wetlands and fire management programs are two specific environmental arenas that have come to overemphasize the tracking of acreage numbers to validate existing policy direction. In both of these arenas, we find the definition and categorization of "countable" acres to be inconsistent and unreliable. We explore this systemic flaw for both wetlands and fire programs and describe its implications for environmental policy and natural resource management more broadly. We conclude with recommendations for improved performance measurement in these arenas.  相似文献   
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Urban stream restoration continues to be used as an ecological management tool, despite uncertainty about the long‐term sustainability and resilience of restored systems. Evaluations of restoration success often focus on specific instream indicators, with limited attention to the wider basin or parallel hydrologic and geomorphic process. A comprehensive understanding of urban stream restoration progress is particularly important for comparisons with nonurban sites as urban streams can provide substantial secondary benefits to urban residents. Here, we utilize a wide range of indicators to retrospectively examine the restoration of Nine Mile Run, a multi‐million dollar stream restoration project in eastern Pittsburgh (Pennsylvania, USA). Examination of available continuous hydrological data illustrates the high cost of failures to incorporate the data into planning and adaptive management. For example, persistent extreme flows drive geomorphic degradation threatening to reverse hydrologic connections created by the restoration and impact the improved instream biotic communities. In addition, human activities associated with restoration efforts suggest a positive feedback as the stream restoration has focused effort on the basin beyond the reach. Ultimately, urban stream restoration remains a potentially useful management tool, but continued improvements in post‐project assessment should include examination of a wider range of indicators.  相似文献   
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Ecological philosophy requires a significant orientation to the role of hope in both theory and practice. I trace the limited presence of hope in ecological philosophy, and outline reasons why environmental hopelessness is a threat. I articulate and problematize recent environmental publications on the topic of hope, the most important worry being that current literature fails to provide the necessary psychological grounding for hopeful action. I turn to the psychology of hope to provide direction for conceptualizing hope and actualizing hoped for states of affairs. If positive moral action is the goal, hope is a vital concept for underwriting ecological philosophy and a practice requiring considerably more attention.  相似文献   
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Abstract: Considerable attention has recently been focused on using levels of developmental instability among members of a population to detect environmental or genetic stresses on animals or plants. It is not yet clear, however, that high developmental instability in a sample of individuals always indicates environmental stress or poor genetic quality. We studied 13 fragmented populations of prairie phlox (   Phlox pilosa L.) to test the hypothesis that developmental instability should decrease with increasing population size—as expected if small populations suffer genetic problems associated with inbreeding or are exposed to more environmental stress than larger populations. We used two different measures of developmental instability, each calculated for two different traits: radial asymmetry of flowers (for petal width and petal length) and modular fluctuating asymmetry of leaves (  for leaf widths at two points along the leaf  ). There were weak but significant correlations among individuals for four of six pairwise combinations of these measures. Surprisingly, three of our four measures of developmental instability showed strong population size effects that were opposite to those expected: developmental instability increased with population size. We conclude that measures of developmental instability cannot be applied uncritically for biomonitoring without considerable knowledge of developmental mechanisms, natural history, and population biology of the species in question.  相似文献   
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