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91.
92.
Renaud FG  Boxall AB  Toy R  Robertson S 《Chemosphere》2004,57(11):1697-1706
Hazard assessment is an essential element in the evaluation of the potential effects of chemical substances on the environment. To date, most work has focused on hazard assessment schemes for the aquatic environment, but in recent years, a number of proposals have been developed for other environmental compartments. Due to limited datasets, the suitability of the toxicity cut-off values in these schemes has not been fully determined and the practicalities associated with using these approaches have not been fully established. This study, which focused on the soil compartment, was performed to examine cut-off values proposed by two terrestrial hazard assessment schemes and establish the availability of data. Data on earthworms indicated that current proposals for toxicity cut-off values are appropriate. However, analysis of IUCLID (International Uniform ChemicaL Information Database) indicates that even for commonly used high production volume chemicals, insufficient data are available to enable classification. Whilst the necessary data may already be available for selected groups of substances (e.g. pesticides and veterinary medicines), a significant experimental testing programme would therefore be required before a terrestrial classification system could be applied widely. Such data may become available in the future as a result of initiatives such as REACH.  相似文献   
93.
A unique archive of photographs from 1969 to 1974 permitted a test of the hypothesis that the diversity and composition of contemporary epilithic communities on subtidal rock walls in the San Juan Islands, WA, USA, has changed over 40 years. Notably, the richness and diversity of sessile taxa was significantly higher in 2008–2011. Furthermore, the multivariate community structure of sessile and mobile taxa differed between the historic and modern eras. Historic communities were characterized by a high percent cover of bare rock and non-calcified algal crusts, consistent with the effects of grazing by chitons and urchins. The rate of sessile community turnover, an index less susceptible to spatial sampling artifacts than richness or diversity, was not significantly different between the two eras. Together with the naturally high spatial variability in these epilithic communities, and the limited replication of historic quadrats, we interpret cautiously the data as evidence of limited change despite a clear shift in temperature and predator (fish) guild composition. The lack of substantial change in rock wall communities may be due in part to their vertical topography, which limits physical disturbance and the preemption of space by weedy algae, two processes that are often associated with “phase-shifts” in other marine ecosystems.  相似文献   
94.
Occupational low back pain (LBP) remains a leading safety and health challenge. This cross-sectional investigation measured the prevalence of LBP in residential carpenters and investigated ergonomic risk factors. Ninety-four carpenters were investigated for LBP presence and associated risk factors. Ten representative job-tasks were evaluated using the Ovako Working Posture Analysis System (OWAS) and ErgoMaster 2D software to measure elements of posture, stress, and risk. Job-tasks were found to differ significantly for total lumbar compression and shear at peak loading (p < .001), ranging from 2 956 to 8 606 N and 802 to 1 974 N respectively. OWAS indicated that slight risk for injury was found in 10 job-tasks while distinct risk was found in 7 of the 10 job-tasks. Seven of the 10 job-tasks exceeded the National Institute for Occupational Safety and Health (NIOSH) action limit of 3 400 N for low back loading. The point prevalence for LBP was 14% while the annual prevalence was 38%.  相似文献   
95.
The auditory thresholds of the AN2 interneuron and the behavioural thresholds of the anti-bat flight-steering responses that this cell evokes are less sensitive in female Pacific field crickets that live where bats have never existed (Moorea) compared with individuals subjected to intense levels of bat predation (Australia). In contrast, the sensitivity of the auditory interneuron, ON1 which participates in the processing of both social signals and bat calls, and the thresholds for flight orientation to a model of the calling song of male crickets show few differences between the two populations. Genetic analyses confirm that the two populations are significantly distinct, and we conclude that the absence of bats has caused partial regression in the nervous control of a defensive behaviour in this insect. This study represents the first examination of natural evolutionary regression in the neural basis of a behaviour along a selection gradient within a single species.  相似文献   
96.
The source data for QRA’s is important to assure meaningful risk assessment results, particularly when the result is to be compared against quantitative risk acceptance criteria. The author’s company is one of the largest global QRA providers and we have concluded that the UK HSE Hydrocarbon Release Database (HCRD) provides the basis for the best leak frequency data as it offers complete leak data collection in a systematic manner, against a known population of equipment and facilities in the UK sector of the North Sea for which there is an accurate parts count estimate. The LEAK program is described. It screens HCRD to remove leak events not associated with full operations inventories and flows (e.g. when isolated for maintenance) and further uses a distribution function that permits frequencies for any arbitrary hole size range to be determined (e.g. 25 mm leaks, 50 mm leaks, full-bore ruptures). An important factor is that leak frequency data is not stationary, offshore operators have improved their control of leak events and the HCRD shows a declining leak rate over time.DNV often uses frequency modification techniques, termed MOR - Modification of Risk. This paper reviews 4 methods developed by the company internationally. These are the Manager Method, the API 581 method, a barrier based method, and a proprietary management system based method. These all permit localization of UK North Sea data to apply to other facilities (onshore or offshore) and with different management systems and mechanical integrity programs.Overall, localized data using MOR is considered more accurate than direct use of UK North Sea data, however validation is an issue. There are no direct comparisons that compare leak statistics over a sufficiently long period with static management systems and integrity programs. Thus MOR techniques remain judgment based approaches, but transparent in methodology and assumptions. The barrier based modification technique is the most directly verifiable of the four MOR methods presented.  相似文献   
97.
We evaluated performance of species distribution models for predictive mapping, and how models can be used to integrate human pressures into ecological and economic assessments. A selection of 77 biological variables (species, groups of species, and measures of biodiversity) across the Baltic Sea were modeled. Differences among methods, areas, predictor, and response variables were evaluated. Several methods successfully predicted abundance and occurrence of vegetation, invertebrates, fish, and functional aspects of biodiversity. Depth and substrate were among the most important predictors. Models incorporating water clarity were used to predict increasing cover of the brown alga bladderwrack Fucus vesiculosus and increasing reproduction area of perch Perca fluviatilis, but decreasing reproduction areas for pikeperch Sander lucioperca following successful implementation of the Baltic Sea Action Plan. Despite variability in estimated non-market benefits among countries, such changes were highly valued by citizens in the three Baltic countries investigated. We conclude that predictive models are powerful and useful tools for science-based management of the Baltic Sea.  相似文献   
98.
99.
跨界、水资源短缺和渔场问题以近期完成的太平洋岛屿全球国际水域评估(GIWA)结果为基础进行了讨论.太平洋岛屿水域面积3000万km2,占全球海洋面积的大约12%,在地理、人口和发展等方面具有多样性.全球性变化,尤其是海平面上升和海面温度的提高,是最主要的跨界关注的问题,因为它影响着生活的方方面面.水资源短缺和不可持续发展的海洋渔业问题也是讨论的议题,因为这些问题在可预见的将来会主宰整个地区,在此以斐济、基里巴斯、汤加的例子加以说明.社会经济因素,例如人口快速增长、城市化、传统生活方式的解体以及现金经济的发展,加剧了环境问题.本文提出了有助于解决这些问题的政策方案.  相似文献   
100.

This paper explores the impact of the frame in which people interpret global warming. In 1999, 637 respondents completed a mail survey in five counties in central Pennsylvania. Half of the sample received questionnaires that framed global warming in terms of the local impacts of mitigation policies, whereas the other half received questionnaires that framed global warming in terms of the national impacts of mitigation policies. The results show a statistically significant but small difference between the local and national frames in the respondents' willingness to support government policies, as well as to take voluntary actions to mitigate climate change.  相似文献   
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