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排序方式: 共有319条查询结果,搜索用时 15 毫秒
311.
This study was to determine the main health-related reasons, age and occupation of those who took early retirement. This was done through an analysis of the data from Poland's Social Insurance Institution (ZUS) from 2000 and 2001. An analysis of these data showed an increase in the number of certificates confirming total inability to work in people over 40 years old. Over 50% of certificates work were issued to workers in 2 age-groups: 45-49 and 50-54. Diseases of the circulatory system, musculoskeletal system and connective tissue as well as mental and behavioural disorders are the main causes of early inability to work. Approximately 70% of people who obtained certificates confirming total inability to work had blue- and blue-and-white-collar jobs.  相似文献   
312.
In this paper we examine the relationship between identification with the environmental movement and support for First Nations' land claims in order to determine the potential for an environmental justice movement in British Columbia. The findings are based on survey data collected from members of a wilderness preservation movement organization based on Vancouver Island. The findings demonstrate that the stronger an individual identifies with the environmental movement, the more s/he supports linking First Nations' land claims to conservation campaigns. We conclude by proposing that the wilderness preservation movement could increase its mobilization potential and widen the scope of the movement by including First Nations' issues in their campaigns. It could do this by expanding its frame to include issues of environmental justice, thereby connecting environmental protection and fair access to resources.  相似文献   
313.
Retrospective ecological risk assessment, restoration, natural resource damage assessment (NRDA) and managing ecosystems all require having a baseline. This policy and practice paper explores the factors that influence baseline selection, and it is suggested that ecological resources would best be served by: (1) integrating NRDA considerations into both future land-use planning and remediation/restoration; (2) selecting a baseline for NRDA that approximates the land-use conditions at the time of occupation (or a preferred ecosystem); and (3) integrating both the positive and negative aspects of industrial occupation into restoration decisions, baseline selection and NRDA. Under the Comprehensive Environmental Response and Compensation and Liability Act (CERCLA), natural resource damages are assessed for injuries incurred since 1980 due to releases, but the release itself may have occurred before 1980. The paper uses the Department of Energy as a case study to examine NRDA and the management of ecosystems. Releases occurred at many DOE sites from the 1950s to the 1980s during nuclear bomb production. It is suggested that the DOE has been responsible not only for injuries to natural resources that occurred as a result of releases, but for significant ecosystem recovery since DOE occupation, because some lands were previously farmed or industrialized. Natural resource injuries due to releases occurred simultaneously with ecosystem recovery that resulted from DOE occupation. While the 1980 date is codified in CERCLA law as the time after which damages can be assessed, baseline can be defined as the conditions the natural resources would have been in today, but for the release of the hazardous substance. It is also suggested that NRDA considerations should be incorporated into the remediation and restoration process at DOE sites, thereby negating the need for formal NRDA following restoration, and reducing the final NRDA costs.  相似文献   
314.
Testosterone mediates male reproductive trade-offs in vertebrates including mammals. In male edible dormice (Glis glis), reproductivity linked to high levels of testosterone reduces their ability to express torpor, which may be expected to dramatically increase thermoregulatory costs. Aims of this study were therefore to analyse behavioural and physiological consequences of reproductive activity in male edible dormice under ecologically and evolutionary relevant conditions in the field. As we frequently encountered sleeping groups in the field, we hypothesized that social thermoregulation should be an important measure to reduce energy expenditure especially in sexually active male edible dormice. Our results revealed that the occurrence of sleeping groups was negatively influenced by male body mass but not by reproductive status or ambient temperature. In reproductive as in non-reproductive males, the number of individuals huddling together was negatively influenced by their body mass. Thus in general males with a high body mass were sitting in smaller groups than males with a low body mass. However, in reproductive males group size was further negatively affected by ambient temperature and positively by testes size. Thus breeders formed larger sleeping groups at lower ambient temperatures and males with larger testes were found in larger groups than males with smaller testes. Measurements of oxygen consumption demonstrated that grouping behaviour represents an efficient strategy to reduce energy expenditure in edible dormice as it reduced energy requirements by almost 40%. In summary, results of this field study showcase how sexually active male edible dormice may, through behavioural adjustment, counterbalance high thermoregulatory costs associated with reproductive activity.  相似文献   
315.
The Appalachian region in the eastern United Sates is home to the Earth's most extensive temperate deciduous forests, but coal mining has caused forest loss and fragmentation. More than 6000 km in Appalachia have been mined for coal since 1980 under the Surface Mining Control and Reclamation Act (SMCRA). We assessed Appalachian areas mined under SMCRA for forest restoration potentials. Our objectives were to characterize soils and vegetation, to compare soil properties with those of pre-SMCRA mined lands that were reforested successfully, and to determine the effects of site age on measured properties. Soils were sampled and dominant vegetation characterized at up to 10 points on each of 25 post-SMCRA mines. Herbaceous species were dominant on 56%, native trees on 24%, and invasive exotics on 16% of assessed areas. Mean values for soil pH (5.8), electrical conductivity (0.07 dS m(-1)), base saturation (89%), and coarse fragment content (50% by mass) were not significantly different from measured levels on the pre-SMCRA forested sites, but silt+clay soil fraction (61%) was higher, bicarbonate-extractable P (4 mg kg(-1)) was lower, and bulk density (1.20 g cm(-1)) was more variable and often unfavorable. Pedogenic N and bicarbonate-extractable P in surface soils increased with site age and with the presence of weathered rocks among coarse fragments. Our results indicate a potential for many of these soils to support productive forest vegetation if replanted and if cultural practices, including temporary control of existing vegetation, soil density mitigation, and fertilization, are applied to mitigate limitations and aid forest tree reestablishment and growth.  相似文献   
316.
The COVID-19 pandemic has had an enormous impact on almost all aspects of human society and endeavor; the natural world and its conservation have not been spared. Through a process of expert consultation, we identified and categorized, into 19 themes and 70 subthemes, the ways in which biodiversity and its conservation have been or could be affected by the pandemic globally. Nearly 60% of the effects have been broadly negative. Subsequently, we created a compendium of all themes and subthemes, each with explanatory text, and in August 2020 a diverse group of experienced conservationists with expertise from across sectors and geographies assessed each subtheme for its likely impact on biodiversity conservation globally. The 9 subthemes ranked highest all have a negative impact. These were, in rank order, governments sidelining the environment during their economic recovery, reduced wildlife-based tourism income, increased habitat destruction, reduced government funding, increased plastic and other solid waste pollution, weakening of nature-friendly regulations and their enforcement, increased illegal harvest of wild animals, reduced philanthropy, and threats to survival of conservation organizations. In combination, these impacts present a worrying future of increased threats to biodiversity conservation but reduced capacity to counter them. The highest ranking positive impact, at 10, was the beneficial impact of wildlife-trade restrictions. More optimistically, among impacts ranked 11-20, 6 were positive and 4 were negative. We hope our assessment will draw attention to the impacts of the pandemic and, thus, improve the conservation community's ability to respond to such threats in the future.  相似文献   
317.
Environmental Science and Pollution Research - In this study, four systems (S1, S2, S3, and S4) were evaluated to determine whether basic oxygen furnace sludge (BOFS), mainly composed of Fe (84%,...  相似文献   
318.
The influence of the polymers' properties on the solid-phase extraction recovery was studied. Different porous copolymers were used: di(methacryloyloxymethyl)naphtalene-divinylbenzene with ester functional groups (DMN-DVB), 4,4'-bis(maleimido)diphenylmethane-divinylbenzene with imide functional groups (BM-DVB), p,p'-dihydroxydiphenylmethane diglycidyl methacrylic ester-divinylbenzene (MEMDE-DVB) and p,p'-dihydroxydiphenylpropane diglycidyl methacrylic ester-divinylbenzene (MEDDE-DVB) with ester end hydroxyl functional groups. The extraction properties of new synthesized polymeric sorbents were compared with these of two commercial polymeric sorbents: styrene-divinylbenzene (SDB-1) and styrene-divinylbenzene with modified surface (StrataX). These sorbents were used in the SPE of phenol and hydroquinone from water samples.  相似文献   
319.
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