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781.
Transport infrastructure is particularly vulnerable to climate impacts as it is designed for long operational lives, and both episodic and seasonal conditions contribute to deterioration, disruption and unsafe incidents. There are some examples of adaptation in transportation design, but many communities do not have the capacity to incorporate climate change considerations into infrastructure planning and management. Researchers worked closely with the City of Prince George, in Central British Columbia, Canada, to build on existing work and explore how the City could plan, design, and maintain roads and other structures to account for climate change. A local steering committee was formed, and created and evaluated 23 potential research topics. Two focus areas were selected for further investigation and explored during a workshop with practitioners, researchers, consultants and other representatives. The workshop precipitated an investigation of projected impacts of climate change on road maintenance and road safety, and plans to explore alternative paving techniques. Outcomes of the case study provide insights regarding climate change and local transportation infrastructure, including: how researchers can engage with local experts to explore adaptation; issues local governments perceive as important; and barriers communities face as they attempt to address vulnerabilities.  相似文献   
782.
783.
Value stream mapping (VSM) is a well-accepted tool within lean manufacturing concept which is often used for analysing and designing the flow of materials and information required to manufacture a product. However, the analysis is static and single product oriented, which fails to cope with either the variation of production plan or a multi-product environment. In addition, the environmental impact of a manufacturing system is highly associated with the dynamic consumption of energy and resources. Despite the recent integration of VSM with simulation or environmental studies (in the domain of energy efficiency), still neglected is the dynamic assessment of all the resources involved in a multi-product production environment. This paper presents a methodology for modelling multi-product manufacturing systems with dynamic material, energy and information flows with the aim to generate economic and environmental value stream maps (E2VSM). The proposed methodology is validated with an industrial case.  相似文献   
784.
An analysis is made of the spatial variability of snowmelt water composition (within and between biogeocenoses), with regard to its long-term dynamics, in pine and spruce forests exposed to airborne industrial pollution from the Europe’s largest Severonikel Copper–Nickel Smelter Complex. Snowmelt waters from under the tree canopy, compared to those from intercrown areas, contain higher concentrations of chemical elements due to their washing and leaching from tree crowns. This is especially true of spruce forests, since the crowns of spruce trees have a high sorption capacity. Distinct trends in the long-term dynamics of snowmelt water composition, related to reduction of industrial emissions, are observed in background forest areas and defoliating forests but not in the vicinity of pollution sources. It is shown that the main factors determining these dynamics in forests of the Kola Peninsula are edificator tree species, airborne industrial pollution, and, possibly, an increase in the number of days with above-zero temperatures in the period of snow accumulation, which facilitates washing and leaching of chemical compounds from tree crowns.  相似文献   
785.
Demographic structure and its seasonal dynamics have been studied in colonies of narrow-skulled voles (Lasiopodomys gregalis Pall.) in Northern Kulunda. Three types of colonies have been distinguished: (I) true colonies (large, complex families), (II) simple families (nuclear or incomplete), and (III) all-male colonies. Changes in their sex, age, and functional composition (based on animal migration activity) during the breeding season have been analyzed.  相似文献   
786.
This study takes an historical approach in order to establish how the form and function of the social-ecological system that represents the Bangladesh south-western coastal zone has changed over recent decades. Time series data for a range of ecosystem services and drivers are analysed to define the range of trends, the presence of change points, slow and fast variables and the significant drivers of change. Since the 1980s, increasing gross domestic product and per capita income mirror rising levels of food and inland fish production. As a result, the size of population below the poverty line has reduced by ~17 %. In contrast, non-food ecosystem services such as water availability, water quality and land stability have deteriorated. Conversion of rice fields to shrimp farms is almost certainly a factor in increasing soil and surface water salinity. Most of the services experienced statistically significant change points between 1975 and 1980, and among the services, water availability, shrimp farming and maintenance of biodiversity appear to have passed tipping points. An environmental Kuznets curve analysis suggests that the point at which growing economic wealth feeds back into effective environmental protection has not yet been reached for water resources. Trends in indicators of ecosystem services and human well-being point to widespread non-stationary dynamics governed by slowly changing variables with an increased likelihood of systemic threshold changes/tipping points in the near future. The results will feed into simulation models and strategies that can define alternative and sustainable paths for land management.  相似文献   
787.
Environmental restoration projects are commonly touted for their ecological positives, but such projects can also provide significant socioeconomic and cultural benefits to local communities. We assessed the social dimensions of a large-scale coral reef restoration project in Maunalua Bay, O‘ahu, where >1.32 million kg of invasive marine macroalgae was removed from 11 hectares (90,000 m2; 23 acres) of impacted coral reef in an urbanized setting. We interviewed 131 community stakeholders and analyzed both quantitative and qualitative data to assess human uses of the environment, assess perceptions of environmental health, and characterize social dimensions (+/?) associated with the invasive algae removal effort. Results indicate substantial direct economic benefits, including the creation of more than 60+ jobs, benefiting more than 250 individuals and 81 households. The project helped develop a skilled workforce in a local business dedicated to environmental restoration and increased the capacity of community organizations to address other threats to reefs and watersheds. Other major benefits include revitalization of Native Hawaiian cultural practices and traditions and the successful use of harvested invasive algae as compost by local farmers. Our results show the project heightened community awareness and a broader sense of stewardship in the area, creating enabling conditions for collective community action. Our findings show that restoration projects that explicitly incorporate efforts to build community awareness, involvement, and a shared responsibility for a site may ultimately create the long-term capacity for sustainable stewardship programs. We conclude by discussing lessons learned for engaging productively with communities in environmental restoration and stewardship, which remains a central focus in conservation worldwide.  相似文献   
788.
789.
Regional Environmental Change - The potential impact of climate change on port operations and infrastructures has received much less attention than the corresponding impact for beach systems....  相似文献   
790.
The aim of this study was to evaluate the accumulation of toxic (As, Cd and Pb) and essential (Cu, Mn and Zn) metals in samples (feathers, liver, kidney, lung, intestine and muscle) of common buzzards (Buteo buteo) from Sicily, used as bio-indicators for monitoring environmental metals pollution. All samples of buzzards were collected at the “Recovery Center of Wild Fauna” of Palermo, through the Zooprophilactic Institute. The quantitative determinations of metals were carried out using an atomic absorbtion spectrophotometer (AAS). The results obtained showed the presence of metals in all samples analyzed. For toxic metals the highest levels of Pb and As were found in liver and those of Cd in kidney; for essential metals Zn levels were higher than Cu and Mn in all tissues analyzed. Significant differences are observed in metal levels between female and male and juvenile and adult bird samples.Highest metal levels found in liver, kidney and muscle can be considered indicative of chronic exposure to metals while the presence of metals in feathers can be consequential to storing and elimination processes. The results obtained suggest that common buzzards (Buteo buteo) may be very useful as bio-indicators for monitoring environmental pollution.  相似文献   
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