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121.
Management of natural environment sites is becoming increasingly complex because of the influx of urbanized society into wildland areas. This worldwide phenomenon impacts a wide range of countries. In southern California ethnicity is often a major factor influencing recreation site use and behavior at sites in the wildland-urban interface. This study investigated the role of ethnicity and race on the use patterns, perception of environment, and recreation behaviors at an outdoor recreation site visited by an ethnically diverse population. Two research questions were asked: (1) What ethnic groups engage in outdoor recreation at this site, and (2) what differences can be assigned to these various groups? Data were collected from 250 recreationists during 1991. Three major ethnic groups were identified, and statistically significant differences were found in the importance of site attributes, activity participation, and in preferred and actual communication channels. Management implications and strategies based on group differences are discussed. 相似文献
122.
Donald A. Wilhite Deborah A. Wood 《Journal of the American Water Resources Association》1985,21(1):31-38
ABSTRACT: Although droughts are a frequent occurrence over much of the United States, response by state and federal government has been ineffective and poorly coordinated. Recently, several states have recognized the value of drought emergency planning and have developed plans to assist them in responding more effectively to prolonged periods of water shortage. These states have created an organizational structure to coordinate the assessment and response activities of state and federal agencies. Each state's drought response plan is unique since each state's water supply and management problems, and their consequent impacts, are unique. The drought response plans developed by Colorado, South Dakota and New York are reviewed here in detail. We recommend that other states affected by frequent and severe water shortages also develop drought emergency plans. These plans will enhance state government's ability to implement effective measures in a timely manner and, ultimately, may provide added incentive for the federal government to develop the national drought response plan called for by the General Accounting Office in 1979. 相似文献
123.
124.
Deborah C. Gregg John D. Stednick 《Journal of the American Water Resources Association》2000,36(1):95-103
ABSTRACT: Macroinvertebrate community data collected from streams in Wyoming were assessed at various scales: within one stream reach, between stream reaches within one stream, between streams, and between stream classes. Fourteen indices including number of individuals/m2, biomass/m2, number of taxa, Shannon's diversity index, and functional feeding group ratios were used to compare macroinvertebrates by stream reach and stream class. Statistical analysis indicated that for five of the 14 indices, significant variability occurred between macroinvertebrate communities within one reach. For two of the remaining nine indices there was significant variability between communities from several reaches within the same stream. For seven of the nine indices, there was significant variability among macroinvertebrate communities from streams of the same class. Variability among the macroinvertebrate communities from the three stream classes was significantly different for seven of the nine indices. ANOVA results suggest that macroinvertebrate communities from different samples within one reach and between reaches within one stream were more comparable than those from different streams and different stream classes. 相似文献
125.
Deborah A. Hutchinson Alan H. Savitzky Akira Mori Jerrold Meinwald Frank C. Schroeder 《Chemoecology》2008,18(3):181-190
Summary.
Rhabdophis tigrinus obtains defensive steroids (bufadienolides) from its diet and sequesters those compounds in specialized structures on its
neck known as nuchal glands. Hatchling snakes lacking these steroids must acquire them from toads consumed as prey. Here we
show that females provision bufadienolides to their offspring in amounts correlated to the quantity in their own nuchal glands;
thus, chemically protected mothers produce defended offspring. Bufadienolides can be provisioned to embryos via deposition
in yolk and by transfer across the egg membranes within the oviducts. Maternally provisioned bufadienolides persist in the
nuchal glands of juvenile snakes from the time of hatching in late summer until the following spring, when toads of ingestible
size become abundant. Therefore, maternal provisioning may provide chemical protection from predators for young R. tigrinus in the absence of dietary sources of bufadienolides. 相似文献
126.
Guillermo Ivan Pereira Patrícia Pereira da Silva Deborah Soule 《Environment, Development and Sustainability》2018,20(1):231-267
The European Union (EU) transition to a smarter and more sustainable electricity sector is driven by climate change adaptation and technological developments. For the electricity distribution industry, this has contributed to a growing need to understand how these network monopolies should adapt their role, activities, and responsibilities for a redesigned electricity market, given the growth of distributed generation, and the increased control and monitoring capabilities. Considering this, a foresight study on business model innovation, technological adaptation, and market design policy alternatives is presented. A Policy Delphi method was applied, involving two iterative survey rounds and 207 European experts, which assessed 57 policy alternatives. The results highlight adaptation challenges for implementing new technologies and business practices. Experts support innovation and transition to new roles, and innovative services, while warranting that core electricity distribution activities are secured. This shift in roles is expected to be achieved through research and development (R&D) support policies, innovation friendly regulatory frameworks, and concerted actions at the EU and Member States level. The results provide policy-adaptation guidelines for electricity distribution industry stakeholders. 相似文献
127.
128.
This paper considers the prevalence and use of external health and safety awards by companies in the United Kingdom. A review is provided of the types of award schemes currently available. The results from two small research projects present data on the benefits that motivate participation in these awards. The results demonstrate that award schemes are used to motivate the workforce, and a comparison is made with company incentive schemes. However, there are a number of further benefits that can be identified. These benefits may have commercial implications, and include improved opportunities in the competitive tendering process and strengthening of community relations. Benefits may also include positive feedback for the health and safety professional that could lead to acknowledgement by senior management of their contribution to the health and safety performance in the organization. 相似文献
129.
Physical changes that occur on the surface of fired shots due to firing and impact with soil may increase the dissolution of muniton metals. Increased metal dissolution could potentially increase metal transport and leaching, affecting metal concentrations in surface and groundwater. This research describes the relationship between the surface changes on fired tungsten-nickel-iron (94% W:2% Ni:4% Fe) composite shots and metals leaching from those shots. Tungsten composite shot was fired into, and aged in, three soil types (Silty Sand, Sandy Clay, and Silt) in mesoscale rainfall lysimeters to simulate live-fire conditions and subsequent interactions between the metals of the composite and soil. Leachate, runoff, and soil samples were collected from the lysimeters and analyzed for metal content. The shots were analyzed using scanning electron microscopy (SEM) to evaluate surface changes. SEM results indicated that a soil’s particle size distribution initially affected the amount of metal that was sheared from the surface of the fired W-composite shots. Shearing was greatest in soils with larger soil particles (sand and gravel); shearing was least in soils composed of small soil particles (fines). Increased metallic shearing from the shot’s surface was associated with increased W dissolution, compared to controls, following a simulated 1 year soil aging. 相似文献
130.
Michael E. Ginevan Deborah K. Watkins John H. Ross Randy A. OBoyle 《Chemosphere》2009,75(11):1512-1518
The Exposure Opportunity Index (EOI) is a proximity-based model developed to estimate relative exposure of ground troops in Vietnam to aerially applied herbicides. We conducted a detailed quantitative evaluation of the EOI model by using actual herbicide spray missions isolated in time and space. EOI scores were calculated for each of 36 hypothetical receptor location points associated with each spray mission for 30 herbicide missions for two time periods – day of herbicide application and day 2–3 post-application. Our analysis found an enormous range of EOI predictions with 500–1000-fold differences across missions directly under the flight path. This quantitative examination of the EOI suggests that extensive testing of the model’s code is warranted. Researchers undertaking development of a proximity-based exposure model for epidemiologic studies of either Vietnam veterans or the Vietnamese population should conduct a thorough and realistic analysis of how precise and accurate the model results are likely to be and then assess whether the model results provide a useful basis for their planned epidemiologic studies. 相似文献