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31.
The conventional gausslan plume equation for ground level concentrations was used to estimate hourly average sulfur dioxide concentrations at selected points in Louisville, KY, on specific days during 1973. Area emission sources were not included in the model since they are not substantial. The trajectory of the emissions from each continuous point source was calculated by a procedure that allowed for spatial variability in wind direction. All other meteorological parameters were held constant during each hour. The twenty-four individual hourly estimates at each location for a given day were arithmetically averaged yielding a daily mean. The model predictions were compared to actual measurements conducted by Jefferson County Air Pollution Control District personnel using the West-Gaeke sampling procedure. The sample correlation coefficient for all predictions was low, but after only about 30% of the predictions were eliminated on statistical grounds, the sample correlation coefficient was increased to 0.72. The statistical analysis appeared to discard a reasonable number of predictions on the basis of observed variability in the measured air quality.  相似文献   
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Although epidemiological studies have found a significant amount of toxins in surface water, a complex link between animals’ access to wastewater and associated animal and human welfare losses needs to be explored. The scarcity of safe water has put stress on the utilization of wastewater for crops and livestock production. The access of animals to wastewater is related to the emergence of dangerous animal’s diseases, hampering productivity, increasing economic losses, and risking human health along the food chain. This review explores use of wastewater for agriculture, epidemiological evidence of microbial contamination in wastewater, and animal and human welfare disruption due to the use of wastewater for crop and livestock production. More specifically, the review delves into animals exposure to wastewater for bathing, drinking, or grazing on a pasture irrigated with contaminated water and related animal and human welfare losses. We included some scientific articles and reviews published from 1970 to 2017 to support our rational discussions. The selected articles dealt exclusively with animals direct access to wastewater via bathing and indirect access via grazing on pasture irrigated with contaminated wastewater and their implication for animal and human welfare losses. The study also identified that some policy options such as wastewater treatments, constructing wastewater stabilization ponds, controlling animal access to wastewater, and dissemination of necessary information to ultimate consumers related to the source of agricultural produce and wastewater use in animal and crop production are required to protect the human and animal health and welfare.  相似文献   
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Most species of benthic marine invertebrates have a single mode of larval development. Poecilogonous species are those that produce more than one type of larval offspring. Reports of variable development within one species, especially in combination with widely differing ecological habitat, are frequently attributed to cryptic species. The spionid polychaete Boccardia proboscidea Hartman, 1940 exhibits development that varies both within a single brood and among broods produced by different females. Some females have planktotrophic development and produce many small larvae with a 2 week planktonic period before metamorphosis. Other females produce broods containing both planktotrophic larvae as well as nurse-egg-ingesting (adelphophagic) offspring that hatch as juveniles. Molecular analysis (RAPD-PCR) showed that a significant proportion of genetic variance is attributable to geographic origin, and not to developmental type. Adults of both developmental types showed no consistent differences in taxonomically important features (e.g. type and arrangement of chaetae, modified fifth setiger, caruncle, branchiae, pygidium) when examined with SEM. These data support the hypothesis that developmental variability in this species is a case of poecilogony, and is not attributable to cryptic species. Received: 21 April 1998 / Accepted: 20 April 1999  相似文献   
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Long-term urban resilience requires urban systems with the capacity to respond to change and disturbance and to enhance the conditions for lasting wellbeing. Over the past century Tokyo has demonstrated impressive resilience, especially a capacity to reorganise and rebuild in response to successive major disturbances. Throughout these recoveries, the city-region maintained a focus on re-establishing, improving and maintaining international competitiveness through industrial development. Green spaces in Tokyo provided a flexible, but gradually disappearing resource. Today, to meet the needs of its ageing and minimally expanding population for enhanced wellbeing, Tokyo requires active transition planning covering many intertwined factors, but the adaptive capacity provided by the green space resource is no longer available. The Tokyo case underscores the risk inherent in the depletion of non-renewable resources (in this instance, green space) to secure immediate recovery and accommodate growth and short-term resilience at the expense of long-term resilience.  相似文献   
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Various types of ecosystem-based climate proxies have been used to assess past arctic change. Although lotic records are relatively poor because of the constant reworking of riverine material, high-quality lentic data have been assembled back to the end of the Pleistocene and deglaciation of the circumpolar Arctic. In general, climatic variations in the Holocene, partly due to changes in the shrinking effect of glacier coverage, produced significant temporal and spatial variations in arctic hydrology and freshwater ecosystems. Of particular note were the vast expansions of northern peatlands during major protracted periods of wetting. More recent lake biota and sedimentiological data reflect the general warming trend that has occurred over the last one to two centuries and indicate major changes to freshwater characteristics such as ice-cover duration and thermal stratification. Such data provide an excellent baseline against which future effects of climate change can be both projected and measured.  相似文献   
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Multinational organizations (MNOs), more so than other organizations, are likely to require individuals with different perspectives, experiences, and backgrounds to form teams and collaboratively manage knowledge. We develop a framework that shows why variations in time perspectives among members of teams occur and how such differences can exert significant but unacknowledged influences on knowledge management efforts in MNOs, including: (1) innovativeness of knowledge created (2) speed of knowledge creation and (3) speed of knowledge transfer between teams. We also provide new insights into benefits of time perspective heterogeneity for teams managing knowledge. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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ABSTRACT: We propose that some watersheds may be better candidates for watershed management than others. The extent of success of watershed management may depend, in part, on attributes intrinsic to watersheds: scientific feasibility, social feasibility, and motivational feasibility. Using illustrations from New Jersey watershed management efforts, we tie scientific feasibility to the nature of environmental problems and the scientific capability to solve them. Social feasibility encompasses civic infrastructure and engagement. Motivational feasibility includes issue salience linked to values or economic considerations. We suggest that assessments should be made about the viability of watershed management in specific watersheds and that priorities should be developed based on these assessments. Research on watershed management should explore not only how to improve watershed management but also where to conduct it.  相似文献   
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Mining generates risk of environmental and social harm for Indigenous peoples but can also generate substantial revenues for them, creating opportunities for community development in a context where economic and social disadvantage is the norm. Especially as mining revenues should, in part, compensate for mining’s negative social and environmental impacts, it is vital that mineral taxation on Indigenous lands reflect a careful assessment of appropriate tax mechanisms and a matching of these with community priorities. Yet little has been written that could serve as a guide for Indigenous decision makers. This article contributes to an understanding of the issues and choices facing Indigenous communities in designing mineral taxation regimes, by focusing on the question of economic risk. Risk arises as a key variable in choosing or designing a mineral taxation regime in three ways. Different approaches to mineral taxation are inherently more or less risky, in the sense that they are more or less certain to generate tax revenues. A second aspect of risk involves the degree of economic certainty or predictability associated with different types of commodities and projects. Third, the risk tolerance of Indigenous peoples and communities can vary significantly. We show how Indigenous groups can integrate and address these different dimensions of risk, by recognising the ‘risk consequences’ associated with different approaches to mineral taxation and choosing an approach that reflects, as fully as possible, the group’s risk tolerance.  相似文献   
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