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101.
This paper examines the impact of training programs on the ability of trainee watch officers to make decisions in collision avoidance situations.It draws on previous studies which have shown that experts are able to manage complex situations in an acceptable way. However, observations of students on simulators have revealed that many of them are unable to manage such situations or even to recall their main features. It is therefore necessary to identify new training tools that will give trainees the capacity to assess a situation quickly and accurately, and to perform satisfactory actions. These would be in addition to formal regulations.Exercises were designed to evaluate the impact of such tools on the decision-making process of trainees. The impact of the type of navigation experienced by trainees during their on-the-job training was also evaluated.Results showed that decision-making exercises did tend to improve the trainees’ capacity to analyse a complex situation; however, they did not have a clear impact on the manoeuvre performed. On the contrary, there was an obvious difference between the trainees who experienced complex avoidance situations during their on-the-job training period and those who did not.At a time where ship-owners are looking to reduce the length of the “on-the-job” training period, these results point to its vital importance. 相似文献
102.
Cecilia Lopez y Royo Gérard Pergent Christine Pergent-Martini Gianna Casazza 《Environmental monitoring and assessment》2010,171(1-4):365-380
The seagrass Posidonia oceanica is extensively monitored in Mediterranean coastal waters and is an ideal candidate for an eco-regional assessment of the coastal ecosystem. The aim of this study is to evaluate the potential of P. oceanica as eco-regional indicator for its assessment at the scale of Mediterranean basin. For this purpose, regional and national P. oceanica monitoring programmes are identified, and their data and metadata are collected and compared in terms of objectives, strategies, sampling designs and sampling methods. The analysis identifies a number of issues concerning data quality, reliability and comparability. In particular, the adoption of different sampling designs and methods may introduce relevant errors when comparing data. The results of this study stress the necessity of carefully planning monitoring programmes. Moreover, it highlights that the adoption of a number of common tools would facilitate all Mediterranean monitoring activities and allows an optimisation of management efforts at an eco-regional scale. 相似文献
103.
Microcystin-LR (MC-LR) was readily biodegraded on addition to six different water samples irrespective of their previous exposure to microcystins. Subsequent studies with water from three of these water bodies confirmed the degradation of MC-LR and also demonstrated the biodegradation of MC-LF, nodularin and mixture of microcystins and nodularin. Rates of degradation of MC-LR, MC-LF and NOD in individual water samples ranged from a half-life of 4 to 18d. Analysis by HPLC-PDA-ESI+ and MALDI MS/MS revealed novel intermediate degradation products of MC-LF and nodularin which included demethylation, hydrolysis, decarboxylation and condensation of the parent compound(s). Our study suggests a possible diversity of micro-organisms and/or pathways which has not been previously observed. 相似文献
104.
105.
On-farm water storages (locally known as farm dams or farm ponds) are an important part of many agricultural landscapes, as
they provide a reliable source of water for irrigation and stock. Although these waterbodies are artificially constructed
and morphologically simple, there is increasing interest in their potential role as habitat for native flora and fauna. In
this article, we present results from a case study which examined the habitat characteristics (such as water physical and
chemical parameters, benthic metabolism, and macrophyte cover) and the macrophyte and macroinvertebrate biodiversity of eight
farm ponds on four properties in the Stanley Catchment, Southeast Queensland, Australia. Each landowner was interviewed to
allow a comparison of the management of the ponds with measured habitat and biodiversity characteristics, and to understand
landowners’ motivations in making farm pond management decisions.
The physical and chemical water characteristics of the study ponds were comparable to the limited number of Australian farm
ponds described in published literature. Littoral zones supported forty-five macroinvertebrate families, with most belonging
to the orders Hemiptera, Coleoptera, Odonata, and Diptera. Invertebrate community composition was strongly influenced by littoral
zone macrophyte structure, with significant differences between ponds with high macrophyte cover compared to those with bare
littoral zones. The importance of littoral zone macrophytes was also suggested by a significant positive relationship between
invertebrate taxonomic richness and macrophyte cover.
The landowners in this study demonstrated sound ecological knowledge of their farm ponds, but many had not previously acknowledged
them as having high habitat value for native flora and fauna. If managed for aquatic organisms as well as reliable water sources,
these artificial habitats may help to maintain regional biodiversity, particularly given the large number of farm ponds across
the landscape. 相似文献
106.
Joanna Burger Jessica Sanchez J. Whitfield Gibbons Jeanine Ondrof Robert Ramos Michael J. McMahon Karen F. Gaines Christine Lord Marie Fulmer Michael Gochfeld 《Environmental monitoring and assessment》1999,57(2):195-211
Although considerable attention is devoted to environmental monitoring and assessment with respect to both pollutants and the status of particular plant or animal populations, less attention is devoted to assessing people's attitudes about the relative importance of ecological resources. In this paper we examine the attitudes and perceptions about ecological resources of people living around the Department of Energy's Savannah River Site (SRS), in South Carolina. Our overall hypothesis is that people who are directly affected by the possible outcomes and consequences of a particular hazard (i.e., those people employed at SRS) will undervalue the risks and overvalue the potential benefits from future land uses that favor continued site activity, compared to people who live near but are not employed at SRS. We interviewed 286 people attending the Aiken Trials horse show on 14 March 1997. There were few gender differences, although men hunted and fished more than women, women ranked three environmental concerns as more severe than did men, and women were more concerned about the effect of SRS on property values. Maintenance of SRS as a National Environmental Research Park ranked first as a future land use; nuclear production ranked second, followed by hunting and hiking. Only residential development ranked very low as a future land use. There were many differences as a function of employment history at SRS: 1) people who work at SRS think that the federal government should spend funds to clean up all nuclear facilities, and they think less money should be spent on other environmental problems than did non-employees, 2) people who work at SRS ranked continued current uses of SRS higher than did people who never worked at SRS, and 3) people who work at SRS are less concerned about the storage of nuclear material or accidents at the site than are people who never worked at the site. 相似文献
107.
Christine E. Wilkinson Alex McInturff Jennifer R. B. Miller Veronica Yovovich Kaitlyn M. Gaynor Kendall Calhoun Harshad Karandikar Jeff Vance Martin Phoebe Parker-Shames Avery Shawler Amy Van Scoyoc Justin S. Brashares 《Conservation biology》2020,34(4):854-867
Carnivore predation on livestock is a complex management and policy challenge, yet it is also intrinsically an ecological interaction between predators and prey. Human–wildlife interactions occur in socioecological systems in which human and environmental processes are closely linked. However, underlying human–wildlife conflict and key to unpacking its complexity are concrete and identifiable ecological mechanisms that lead to predation events. To better understand how ecological theory accords with interactions between wild predators and domestic prey, we developed a framework to describe ecological drivers of predation on livestock. We based this framework on foundational ecological theory and current research on interactions between predators and domestic prey. We used this framework to examine ecological mechanisms (e.g., density-mediated effects, behaviorally mediated effects, and optimal foraging theory) through which specific management interventions operate, and we analyzed the ecological determinants of failure and success of management interventions in 3 case studies: snow leopards (Panthera uncia), wolves (Canis lupus), and cougars (Puma concolor). The varied, context-dependent successes and failures of the management interventions in these case studies demonstrated the utility of using an ecological framework to ground research and management of carnivore–livestock conflict. Mitigation of human–wildlife conflict appears to require an understanding of how fundamental ecological theories work within domestic predator–prey systems. 相似文献
108.
109.
Chang-Hee Christine Bae 《Journal of Environmental Planning and Management》1997,40(2):235-260
This paper examines how air pollution control policies will affect the welfare of the different races in Southern California. The paper adopts the concept of the Net Welfare Impact (NWI) function to measure how air quality improvements affect the welfare (monetary and non-monetary) of individual households. The core finding is that many of the benefits of air quality improvement are enjoyed by minorities, especially Latinos (and African-Americans and Asians to a lesser extent), whose household incomes tend to be lower and family size larger than the regional average, and who are more likely to live in the neighbourhoods that are currently polluted. Thus, because minorities have suffered more from dirty air, they are the major beneficiaries from implementation of clean air policies. This is the result of the Federal clean air mandate that dictates uniform standards for all metropolitan areas. 相似文献
110.
Christine A. Matthews 《Journal of the American Water Resources Association》1991,27(5):841-847
ABSTRACT: Southern California, now in its fifth consecutive year of drought, has always relied heavily on imported water from the Owens Valley, the State Water Project, and the Colorado River. For various reasons, these sources are now decreasing and water suppliers are being forced to look for new sources. One possible alternative is to store water obtained during peak supply periods for use during dry periods in ground water storage basins. The Santa Ana River Basin in Orange County has already been developed, and is being used to provide water to 25 cities in Orange County. The San Juan Basin, also in Orange County, is being studied as a possible future storage basin. This paper examines some of the positive and negative aspects of developing and using ground water storage basins in Southern California. 相似文献