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51.
52.
Rocío A. Baquero Francisco J. Oficialdegui Daniel Ayllón Graciela G. Nicola 《Conservation biology》2023,37(5):e14165
The European Union's (EU) environmental legislation establishes common measures to prevent the entry and spread of invasive non-native species and to minimize their impacts. However, species that are native to at least one member state but non-native and potentially invasive in others (NPIS) are in limbo because they are neither legally regulated at the EU level nor in most member states. We used the Communication and Information Resource Centre for Administrations, Businesses and Citizens (CIRCABC) raw data on NPIS (317 taxa) to analyze their distribution across the EU and identify which biogeographical regions are the main sources of invasions. We additionally evaluated the conservation challenge posed by NPIS that are threatened within their native ranges. We performed a pairwise analysis summarizing the number of species that are native to a given member state but non-native to another and vice versa. Although distribution patterns of NPIS varied across taxa groups, overall, southern and central EU countries were both donors and recipients of NPIS. Eastern countries were mainly a source, and western and northern countries mostly received NPIS. Around 27% of NPIS were threatened in some of their EU native ranges, which is a challenge for conservation and management because some of them have serious negative effects on European biodiversity, but hitherto remain outside the scope of the EU regulation of invasive non-native species. This highlights an unresolved paradox because efforts to manage species as invasive conflict with efforts to protect them as threatened within the same territory. 相似文献
53.
模糊控制理论在煤矿通风安全自动化系统中的应用 总被引:9,自引:1,他引:8
由于煤矿通风系统的独特性和复杂性 ,要精确地建立具有时滞及控制对象的数学模型遇到较大的困难 ,因此 ,人们寻求了一些新的解决途径。笔者基于模糊控制理论 ,并提出将其应用于煤矿通风自动化系统中 ,同时采用单片机来实现模糊控制 ,实践证明 ,此法取得良好效果 ;与常规的控制方法相比 ,模糊控制方法具有响应快、控制简单、不需建模等特点 ,适用于矿井通风自动化系统 ;笔者还讨论了调节窗模糊控制系统设计 ,系统的单片机实现及软件编制 ,并进行了实验及实验结果分析 ;最后提出了向自组织方向的深化方案。 相似文献
54.
Introduction: A regulatory training standard for construction workers using fall protection equipment became mandatory in 2015 in the province of Ontario, Canada. By the end of the transition period in 2017, 418,000 workers had been trained to the new standard. Two primary research questions were posed: (1) To what extent does the WAH training affect practices at the worksite? and (2) Has there been a change in the incidence of fall-from-height injuries coincident with the introduction of the WAH Training Standard? Materials and methods: A longitudinal survey of 633 learners was conducted in 2017 at one-, four- and seven-week post-training. A quasi-experiment estimated the incidence of lost-time injuries attributed to falls from heights in 2017 compared to 2012–2014 for a census of construction workers insured for work disability in Ontario, Canada. Results: Learners self-reported substantial increases in knowledge of and improvements in safe work practices when working at heights. The incidence rate of lost-time claim injuries attributed to falls targeted by the training declined by 19.6% (95% CI: 10.7, −27.6), compared to corresponding declines of 2.1% (95% CI: −6.3, 9.9) for other fall injuries and 7.2% (95% CI: 1.8, 12.3) for non-fall traumatic injuries. The observed decline was largest among the smallest employers (<5 full-time equivalent employees). Conclusion: The evaluation findings provide consistent support for a conclusion that the mandatory training standard was effective in reducing the incidence of injuries targeted by the training. However, the effects were modest and did not eliminate the problem. Practical application: A mandatory training standard should be considered as one approach to preventing traumatic injuries. However, other approaches higher in the hierarchy of risk controls should also be considered. 相似文献
55.
首先探讨了特许权经营后政府对城市污水处理厂实行质量管制的必要性;然后,针对当前对污水处理服务进行质量管制存在的普遍问题,通过分析政府管制机构与污水处理厂基于质量的博弈行为,提出了对城市污水处理厂实行有效质量管制的几点建议。 相似文献
56.
According to the United States Environmental Protection Agency (US EPA), a significant percentage of residential onsite sewage
systems (OSSs) are failing at any given time. The US EPA has therefore issued a set of recommended guidelines for OSS regulatory
programs aimed at reducing overall failure rates. We conducted a survey of OSS regulatory program administrators with jurisdictions
bordering a Great Lake. Our goal was to determine their programs’ capacities to meet the US EPA’s recommendations. We found
that although some local programs meet the US EPA’s recommendations, most do not. In this article, we present our findings
and conclusions for one of the US EPA’s models, the baseline “Homeowner Awareness” model. Most areas do not have recommended
requirements that systems be inspected when properties transfer between owners. A majority do not track changes in ownership
within the computerized databases they use to record information about systems. Although most provide at least “one-time”
information to homeowners regarding proper OSS maintenance, most do not contact them periodically with reminders of needed
maintenance. We include recommendations for resolving some of the issues that our research identified. 相似文献
57.
Centner TJ 《Environmental management》2006,37(6):745-752
As point sources of pollution in the United States, concentrated animal feeding operations (CAFOs) are subject to the National
Pollution Discharge Elimination System permitting system requirements. Changes to federal regulations in 2003 and a 2005 court
decision have increased the governmental oversight of CAFOs. Manure application to fields from “large CAFOs” that results
in unpermitted discharges can be regulated under the Clean Water Act. The U.S. Environmental Protection Agency’s interpretation
of agricultural stormwater discharges was approved so that unpermitted discharges may arise if an owner or operator of a CAFO
fails to apply manure correctly. Owners and operators do not, however, have a duty to secure governmental permits in the absence
of a discharge. Turning to the federal provisions regarding nutrient management plans, a court found that they were deficient.
Moreover, the federal government needs to reconsider requirements that would reduce pathogens from entering surface waters.
Although these developments should assist in reducing the impairment of U.S. waters, concern still exists. Greater oversight
of nutrient management plans and enhanced enforcement efforts offer opportunities to provide greater assurance that CAFO owners
and operators will not allow a discharge of pollutants to enter surface waters. 相似文献
58.
Torkild Tveraa Bernt-Erik Sæther Ronny Aanes Kjell Einar Erikstad 《Behavioral ecology and sociobiology》1998,43(2):73-79
In Procellariiformes, the parents guard the chick after it has attained homeothermy. This strategy may reduce the probability
that a small chick is taken by predators, but is costly as only one parent can forage at a time. The decision to leave the
chick may therefore be a compromise between the chick's vulnerability to predators, the body condition of the parent on the
nest and whether the foraging parent returns in time. We studied how the number of days that parents guarded the chick was
related to the body mass of the parent at the nest and the time the foraging parent spent at sea in the Antarctic petrel Thalassoica antarctica. We also examined how the body mass of the parent on the nest and the duration of the foraging trips influenced the chicks'
body condition at the end of the guarding period. When the foraging parent did not return to the nest in time to relieve its
mate, the number of days the parent on the nest kept guarding the chick was positively related to its body mass on arrival
in the colony. The number of days the foraging parent spent at sea was positively related to the body mass of its mate, but
those that returned in time had a shorter stay at sea relative to their mate's body mass than those that did not return before
their mate had left. Apparently, both the body mass of the parent at the nest and the ability of the foraging parent to adjust
its stay at sea to the mate's body mass is important for the number of days the parents guard the chick and also the chick's
body condition at this point. The inability to return to the nest before the mate has left may be the result of needing a
minimum amount of time at sea to find food, or because some parents having low foraging success and therefore prolong their
stay at sea.
Received: 10 October 1997 / Accepted after revision: 14 March 1998 相似文献
59.
S. Stiernström A. Enell O. Wik K. Hemström M. Breitholtz 《Waste management (New York, N.Y.)》2014,34(2):421-429
The Waste Framework Directive (WFD; 2008/98/EC) states that classification of hazardous ecotoxicological properties of wastes (i.e. criteria H-14), should be based on the Community legislation on chemicals (i.e. CLP Regulation 1272/2008). However, harmonizing the waste and chemical classification may involve drastic changes related to choice of leaching tests as compared to e.g. the current European standard for ecotoxic characterization of waste (CEN 14735). The primary aim of the present study was therefore to evaluate the influence of leaching conditions, i.e. pH (inherent pH (~10), and 7), liquid to solid (L/S) ratio (10 and 1000 L/kg) and particle size (<4 mm, <1 mm, and <0.125 mm), for subsequent chemical analysis and ecotoxicity testing in relation to classification of municipal waste incineration bottom ash. The hazard potential, based on either comparisons between element levels in leachate and literature toxicity data or ecotoxicity testing of the leachates, was overall significantly higher at low particle size (<0.125 mm) as compared to particle fractions <1 mm and <4 mm, at pH 10 as compared to pH 7, and at L/S 10 as compared to L/S 1000. These results show that the choice of leaching conditions is crucial for H-14 classification of ash and must be carefully considered in deciding on future guidance procedures in Europe. 相似文献
60.
本文通过对天津市实施国家和地方环境标准中存在问题的调查与分析,提出了若干建议:1)我国环境标准体系需进一步完善与协调;2)适时修订标准,为管理服务:3)理顺各类标准与政策、制度的关系. 相似文献