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451.
Larssen T  Brereton C  Gunn JM 《Ambio》2003,32(3):244-248
During much of the 1900s, the lakes in Killarney Provincial Park have been exposed to high levels of acid deposition due to sulfur emissions from the nearby metal smelters in Sudbury. The sulfur emissions from this large point source have decreased to about 10% of what they were in the 1960s. Lake water quality in Killarney Park has greatly changed in response to reduced emissions, with noticeable declines in sulfate, aluminum and calcium concentrations. Here we apply the dynamic acidification model MAGIC to 3 lakes in Killarney Park. The lakes, which have different buffering capacities and response times, were selected to represent fast, intermediate and slow recovery from acidification. The model was calibrated to match observed data for the lakes and 4 different forecast scenarios for future sulfur deposition reductions were applied. The results indicate that there is still a large potential for improvement in the water quality in Killarney. The recovery time for the different lakes varies greatly. For the lake having the slowest response time several decades are needed for the chemistry to stabilize after implementation of deposition reductions.  相似文献   
452.
This paper examines controversy during the 2001 foot-and-mouth outbreak after mass carcass burial sites were selected at two sites in northeast England, and focuses on shortcomings in public consultation surrounding the carcass disposal policy. The slaughter of six million animals necessitated a national disposal strategy on a hitherto unknown scale. The belated decision to concentrate carcass disposal in a small number of mass burial sites provoked more opposition in the two ex-mining localities selected in the northeast than anywhere else. In both cases local liaison committees were established to manage dialogue between residents and public authorities. We argue that, although seen by the authorities primarily as a vehicle for risk communication and public reassurance, for residents these functioned chiefly as a vehicle for holding public authorities to account. These divergent purposes were overshadowed by the chaotic circumstances in which the early stages of the mass burial policy were implemented, and the way in which the carcass disposal policy was dictated by the operation of the slaughter policy, whose draconian form precluded any but the most cursory public consultation.  相似文献   
453.
The urban fringe has been described as 'planning's last frontier'; a zone of transition and interface between town and country where a broad variety of land uses and activities come together, and where development pressure is often intense.

In this paper, we argue that the urban fringe possesses special characteristics, making it more than simply a transitional landscape. These characteristics centre on patterns of land use, biodiversity and leisure/development opportunity which are unique to the urban edge and to land extending away from built-up areas. The uniqueness, diversity and particular dynamics of the urban fringe demands a special brand of planning and management response. Therefore we suggest that the principle of 'multi-functionality' provides a framework for action, showing how diversity can be managed and supported. Through brief case studies, we demonstrate how functional interactions at the urban fringe might be promoted in the future.  相似文献   
454.
This study examined the relationship of specific religions and degree of religious beliefs to various job-related attitudes and values such as motivational needs, job satisfaction, work ethic, and work, job and organizational commitment. Subjects were 222(107 male, 115 female) managerial and non-managerial workers in the Rocky Mountain area. Results showed no significant correlations between work-related altitudes and specific religious affiliation or degree of religious conviction. However, religious conviction was significantly finked to organizational rank, with non-managerial employees reporting a higher degree of religious conviction than managerial employees. Protestant workers scored higher in Protestant Work Ethic than did non-Protestants and persons with no religious affiliation had higher need for Power than Protestants, Catholics or affiliates of Eastern religions.  相似文献   
455.
ABSTRACT

The transition to more sustainable energy systems has set about redefining the social roles and responsibilities of citizens. Implicit in this are expectations around participation, though the precise contours of what this might mean remain open. Debates around the energy transition have been skewed towards a normative construct of what it means to be a ‘good citizen’, the parameters for which are shaped by predetermined visions of statist and/or market-driven determinations of the energy systems of the future. This article argues that concepts such as ‘energy citizen’ are co-opted to reflect popular neoliberal discourses, and ignore crucial questions of unequal agency and access to resources. Paradoxically, official discourses that push responsibility for the energy transition onto the ‘citizen-as-consumer’ effectively remove agency from citizens, leaving them largely disconnected and disempowered. Consequently, energy citizenship needs to be reconceptualised to incorporate more collective and inclusive contexts for action. Considering how much energy consumption occurs in (traditionally female) domestic spheres, do conventional notions of citizenship (especially with regards to its associated rights and duties) need to be recalibrated in order for the concept to be usefully applied to the energy transition?  相似文献   
456.
When water supply improvements are coupled with opportunity to create income through micro–enterprises, time released from water collection is converted into income earned. This brings several benefits: reduced drudgery, higher household income, and, consequently, greater women's empowerment through changing gender relations within the household. This article documents the performance of one such scheme in Banaskantha District in the state of Gujarat in India, one of poorest districts in the state and the country. Here, due to the efforts of the Self–Employed Women's Association (SEWA), an Indian NGO, poor women are reaping the social and economic benefits of a government–run regional piped water supply scheme, a project funded by Dutch bilateral aid, focusing on women's development. If government policy–makers took the cue and formulated programmes and schemes that combined these two aspects, viz., actions that release time for rural women from daily chores (e.g., collecting water, fuel wood and fodder)and opportunities for sustainable micro–enterprises to convert time saved into income, this could become a reliable route out of rural poverty into gender–sensitive sustainable development.  相似文献   
457.
To perform preimplantation DNA diagnosis for Duchenne muscular dystrophy (DMD) in a female carrier of a dystrophin gene deletion of exons 3–18, we developed a polymerase chain reaction (PCR)-based assay of exon 17 sequences. Exon 17 was efficiently amplified in all 50 single blastomeres of normal control embryos and in five blastomeres of one male embryo of the DMD carrier obtained after a first preimplantation diagnosis (PID) for gender determination. In ten blastomeres of another two male embryos of the DMD carrier, no PCR signals were observed, probably as a result of the deletion. After intracytoplasmic sperm injection, embryos were analysed for exon 17 and three of the four embryos showing normal PCR signals were replaced, resulting in a singleton pregnancy. Prenatal diagnosis showed a female karyotype and DNA analysis indicated that the fetus was not a DMD carrier.  相似文献   
458.
Summary We examined maternal energy expenditure in Rocky Mountain bighorn sheep to test the hypothesis (Trivers and Willard 1973) that individual sons in polygynous mammals should obtain a larger maternal subsidy. In accord with theory, males weighed more at birth (an index of relative prenatal expenditure), tended to suckle more between 40 and 100 days of age (an index of relative postnatal expenditure) and imposed greater delays on their mothers' return to estrus in the subsequent breeding season (an index of relative total preweaning expenditure). Mothers rather than offspring appeared to have primary control over postnatal expenditure. The effect of maternal reproductive effort on return to estrus was cumulative over a period of 3–5 years so that ewes making relatively large expenditures gave birth progressively later. Ewe and lamb mortality was associated with late conception in the previous rut. Thus, differential reproductive effort by ewes in this population appeared to entail a fitness cost involving reductions in both offspring and maternal survivorship. Correspondence to: J.T. Hogg at the present address  相似文献   
459.

Background

A vast amount of data on the concentration of substances in soils is being generated in environmental monitoring programmes. This data has to be assessed in terms of effects on terrestrial biota. Benchmarks for such an assessment have been missing up to now. This gap has been filled by the development of a concept for the derivation of ecotoxicologically based soil quality criteria (SQC) and the application of this concept to environmentally relevant substances.

Objectives

The derivation method was applied to arsenic. The derivation process was described in detail from the compilation of data regarding effects on microbial processes, plants, and soil invertebrates to the formulation of a recommendation for an SQC.

Methods

The conceptual framework for the derivation of ecotoxicologically based SQC was developed after reviewing national and international concepts for the assessment of the effects of substances on terrestrial communities. For the assessment of arsenic effects, all relevant biotic processes and trophic levels have been taken into account. Moreover, soil characteristics that may affect the toxicity to biota have been reviewed.

Results

Effects of arsenic on biota may occur at soil background concentrations or slightly above. There are only a few studies in which the influence of soil characteristics, such as soil pH, soil texture, and soil organic carbon, on the effects of arsenic has been investigated systematically. That is why the SQC was oriented on soil background concentrations for sandy soils (5 mg As/kg soil dw). A comparison of the SQC derived in this work with ecotoxicologically based soilquality values from Canada, Denmark, the Netherlands, and the United States shows an average value of 16 mg As/kg, with a range between 5 and 34 mg/kg. The variations in the soil quality values are mainly due to differences in the derivation approaches.

Conclusions and Outlook

The concept applied is considered suitable for the derivation of SQC designed to protect terrestrial communities against direct effects of substances in soils. Therefore, its use is planned to derive SQC for other environmentally relevant substances. In addition to compensation factors, statistical methods should be taken into account to compensate for risks which cannot be quantified. Furthermore, there is the need for an assessment of indirect effects of soil contaminants on birds and mammals.  相似文献   
460.
Predation is often considered an important factor in the evolution of sociality among animals. We studied mortality patterns and grouping behavior of white-nosed coatis (Nasua narica) at sites in southern Arizona, USA, and western Jalisco, México. Coatis were monitored by radio-tracking and recaptures for more than 3 years at each site. In both populations, predation by large felids, including jaguars (Panthera onca) and pumas (Puma concolor), accounted for more than 50% of mortality of adult coatis. Predation rates were significantly higher on solo coatis than on coatis in groups at both study sites. Predation rates were negatively related to group size in Arizona. However, mortality of juveniles, as measured by the ratios of juveniles to adult females, was not related to the number of adult females per group in Arizona or Jalisco. Coatis exhibit a suite of behaviors, including foraging with the juveniles in the center of the group, sharing vigilance, alarm calling, mobbing and attacking predators, and a highly synchronous birth season, that are all consistent with the hypothesis that predation has played an important role in shaping coati social behavior.  相似文献   
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