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61.
Given many potential obstacles, what types of strategic plans and measures for climate protection and/or energy sustainability are more likely than others to be adopted by cities? What are the key internal and external obstacles to adopting and implementing these plans and measures? Based on data obtained from a survey conducted from 2010 to 2011 and other sources, this paper develops a framework derived from political contracting theory and strategic orientation literature to examine how public management obstacles, socio-economic factors, and political factors influence a city's likelihood of having strategic energy sustainability plans and measures in place. Moreover, this paper finds that many California cities remain reluctant to require residents and businesses to comply with more challenging sustainability measures, such as smart-growth land-use practices, and that those cities with a strategic energy sustainability plan already in place tend to be more willing to adopt smart-growth land-use measures.  相似文献   
62.
Urban growth is a key issue for spatial planning as it influences urban patterns and disrupts open landscapes. To effectively steer urban growth towards compact urban forms, many growth-management policies have been developed over recent decades. However, few studies have assessed how municipal policy mixes have evolved over time. In our representative Swiss-wide survey, we evaluated the prevalence and the time of introduction of 18 policies. Our results indicate that large municipalities use a broad range of reinforcing policies over decades. In contrast, small municipalities mostly rely on conventional land-use regulations. The lack of innovative, incentive-based policies casts doubt on small municipalities' ability to effectively manage urban growth. However, our analyses reveal recent efforts by small municipalities to diversify approaches to growth management and adopt innovative policies. These efforts should be supported by guiding small municipalities in their policy choices, and providing support to those lacking planning capacity.  相似文献   
63.
ABSTRACT: Forces driving the initiation of watershed management activities in Alabama have ranged from top-down, agency-led initiatives to bottom-up, citizen-led initiatives. A number of watershed projects in Alabama were examined including three NPS projects funded by U.S. EPA grants and a more comprehensive locally-initiated watershed management authority. Watershed projects were categorized into four different models. Factors which produced significant differences in the development and utilization of social capital and local capacities for watershed management were investigated. The success of watershed management initiatives was examined qualitatively and appears to correlate with a number of social factors. These factors include the extent of stakeholder involvement, the availability of social capital in the watershed, and the presence of a real or perceived water resource concern or problem. Both short term project success and the longer term prognosis for continued watershed management activities seems to depend most upon the amount of social capital in the watershed. Two major changes in resource management programs and organizations could lead to increased focus on and support for local watershed management initiatives. These are reorganization of resource management agencies around watershed units, and assignment of at least one staff person in each watershed unit to watershed management.  相似文献   
64.
Estimates of biodiversity change are essential for the management and conservation of ecosystems. Accurate estimates rely on selecting representative sites, but monitoring often focuses on sites of special interest. How such site-selection biases influence estimates of biodiversity change is largely unknown. Site-selection bias potentially occurs across four major sources of biodiversity data, decreasing in likelihood from citizen science, museums, national park monitoring, and academic research. We defined site-selection bias as a preference for sites that are either densely populated (i.e., abundance bias) or species rich (i.e., richness bias). We simulated biodiversity change in a virtual landscape and tracked the observed biodiversity at a sampled site. The site was selected either randomly or with a site-selection bias. We used a simple spatially resolved, individual-based model to predict the movement or dispersal of individuals in and out of the chosen sampling site. Site-selection bias exaggerated estimates of biodiversity loss in sites selected with a bias by on average 300–400% compared with randomly selected sites. Based on our simulations, site-selection bias resulted in positive trends being estimated as negative trends: richness increase was estimated as 0.1 in randomly selected sites, whereas sites selected with a bias showed a richness change of −0.1 to −0.2 on average. Thus, site-selection bias may falsely indicate decreases in biodiversity. We varied sampling design and characteristics of the species and found that site-selection biases were strongest in short time series, for small grains, organisms with low dispersal ability, large regional species pools, and strong spatial aggregation. Based on these findings, to minimize site-selection bias, we recommend use of systematic site-selection schemes; maximizing sampling area; calculating biodiversity measures cumulatively across plots; and use of biodiversity measures that are less sensitive to rare species, such as the effective number of species. Awareness of the potential impact of site-selection bias is needed for biodiversity monitoring, the design of new studies on biodiversity change, and the interpretation of existing data.  相似文献   
65.
SUMMARY

The search for innovative methods for improving relations between parks and people has led to various conservation and development projects around the world. Nepal's almost three decades of experience in park management in a variety of institutional settings offers valuable lessons in the challenges and opportunities for enlisting local support for conservation. Citing several macro and micro-level case studies from around the country, this paper provides a comparative perspective on the significance of tourism-focused conservation and community development activities in resolving conflicts between parks and local people.  相似文献   
66.
SUMMARY

An approach to the rehabilitation of degraded community lands built on people's perceptions and traditional knowledge was developed, implemented on a small scale (6 ha plot), and evaluated in terms of economic and ecological costs and benefits over a period of 5 years in a mid-altitude (1200 m) village of Garhwal Himalaya. Rehabilitation comprised establishment of water harvesting tanks, organic management of soil, agroforestry (native multipurpose trees t traditional crops), and decision making by the whole village community. Costs and benefits under irrigated and unirrigated conditions were compared. The total cost of establishing the irrigated agroforestry system was 1.23 fold that of the unirrigated one, whereas the total benefit was 2.09 fold. The average standing above-ground biomass of the 4-year-old plantation in the irrigated agroforestry system was 11.69 t/ha compared to 8.34 t/ha in the unirrigated system. Improvement in soil properties was more pronounced in the irrigated system than in the unirrigated one. Nutrient input, an input derived largely from forest biomass, in the unirrigated system was nearly 3 times higher than that in the irrigated system. It is concluded that, considering the local and national/regional/global interests in an integrated manner, agroforestry incorporating water management would be a more effective option for rehabilitating degraded community lands than the afforestation currently being attempted by the government in the mid-altitudes of Indian Himalaya.  相似文献   
67.
Climate change and sustainable development concerns have motivated some municipalities in Canada to develop community energy plans, which focus on energy needs at the local level for the development of efficient, economical and environmental energy systems. Five Canadian cities that were early adopters of community energy planning principles were studied to assess whether implementation has occurred and what barriers have been experienced. The cities achieved success in the implementation of energy management in municipal operations despite barriers in jurisdiction, perception of cost, communication and capacity, but energy management in the community had not been fully implemented and long-term changes were not prevalent. While reductions were made in the greenhouse gas (GHG) emissions produced by municipal operations, the community's overall GHG emissions were not significantly reduced. Long-term impacts on a city's function and growth will be key if community energy planning is to significantly impact community-wide GHG emissions and energy use.  相似文献   
68.
The aim of this paper is to understand how local residents participate in the construction of local environmental problems and to evaluate a particular analytical approach in environmental sociology to study this phenomenon. The paper is based on an interview study with a sample of local residents. The analysis demonstrates how the local residents attempt to construct a local environmental problem. In particular, the study focuses on how involved actors are positioned, how different sorts of knowledge claims are used, and how the neglect the residents perceive from the authorities affects the attempt to construct a local environmental problem. The study shows that the local residents play a central role in the construction of the situation and that the evaluated model could be very helpful as an analytical tool in the investigation of local residents' participation in the construction of environmental problems.  相似文献   
69.
The possible role of parish and town councils (local councils) in the local implementation of sustainable development has been overlooked both in research and in policy-making. This article is based on research into local councillors' attitudes to sustainability and to their own role within a single county. A “discourse of local council legitimation” is identified, in which local councillors see their communities as living organisms, whose interests they represent with the benefit of local knowledge and holistic thinking – characteristics which they see as absent at other levels of government. Local councillors essentially see their role as local and relatively short-term – a perspective that will have to be addressed if local councils are to make a significant contribution to sustainability.  相似文献   
70.
Ahn, Jae Hyun and Hyun Il Choi, 2013. A New Flood Index for Use in Evaluation of Local Flood Severity: A Case Study of Small Ungauged Catchments in Korea. Journal of the American Water Resources Association (JAWRA) 49(1): 1‐14. DOI: 10.1111/jawr.12025 Abstract: The aim of this article is to develop a new index measuring the severity of floods in small ungauged catchments for initial local flood information by the regression analysis between the new flooding index and rainfall patterns. Although a rapid local flood caused by heavy storm in a short period of time is now one of common natural disasters worldwide, such a sudden and violent hydrologic event is difficult to forecast. As local flooding rises rapidly with little or no advance warning, the key to local flood forecasting is to quickly identify when and where local flooding above a threshold is likely to occur. The new flooding index to characterize local floods is measured by the three normalized relative severity factors for the flood magnitude ratio, the rising curve gradient, and the flooding duration time, quantifying characteristics of flood runoff hydrographs. The new flooding index implemented for the two selected small ungauged catchments in the Korean Peninsula shows a very high correlation with logarithm of the 2‐h maximum rainfall depth. This study proposes 30 mm of rainfall in a 2‐h period as a basin‐specific guidance of precaution for the incipient local flooding in the two study catchments. It is expected that the best‐fit regression equation between the new flooding index and a certain rainfall rate can provide preliminary observations, the flood threshold, and severity information, for use in a local flood alert system in small ungauged catchments. Editor's note: This paper is part of a featured series on Korean Hydrology. The series addresses the need for a new paradigm of river and watershed management for Korea due to climate and land use changes.  相似文献   
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