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111.
Ligía Noronha 《Natural resources forum》2001,25(1):53-65
The objective of this article is to illustrate the use of a framework to design a set of tools to assess progress towards improved well-being in a mining region. The framework uses an ecosystem approach to assess human well-being and is sensitive to the needs, concerns, and interests of at least the major stakeholders: government, company and community. The framework seeks to be useful to stakeholders and to be of policy relevance. The article presents the proposed framework with illustrations from a case study in Goa, India. Mining in Goa has had both positive and negative impacts on the well-being of local people. These impacts vary depending on the age of mining. In areas where mining is well established and active, the economic impacts are more positive. The social and environmental impacts are more negative in the regions where mining is new or is closing down. These characteristics generate their own set of issues of concern to stakeholders. Based on these issues, three types of tools to assess current well-being and progress towards improved well-being are suggested: (i) Indicators based on identified issues using the Pressure-State-Response (PSR) framework; (ii) A quality of life instrument, which can be developed either as an aggregate measure of well-being or in a more limited way to capture the satisfaction of the community with their living conditions; (iii) A regional income accounting framework to assess whether the mining region is able to continue functioning into the indefinite future without being forced into a decline through the degradation of its key natural, social, and human assets and resources. The article suggests that if these tools are used regularly, an information system will emerge that will, over time, provide markers of what mining is doing to the region and to the local communities. 相似文献
112.
The idea that natural selection can be meaningfully applied at the group level may be more important than previously thought. This perspective, a modern version of group selection, is called multilevel selection. Multilevel selection theory could incorporate previous explanations for the evolution of cooperation including kin selection. There is general agreement that natural selection favors noncooperators over cooperators in the case of an unstructured population. Therefore, the evolution of cooperation by multilevel selection often requires positive assortment between cooperators and noncooperators. The question is how this positive assortment can arise in the ecological meaning. We constructed an individual-based model of multilevel selection and introduced migration and evolution. The results showed that positive assortment was generated especially when a migration strategy was adopted in which individuals respond specifically to bad environmental conditions. It was also shown that the founder effect in the evolutionary process could further facilitate positive assortment by working with migration. We analyzed assortment by using relatedness defined in group-structured populations. The fact that cooperation was achieved by such migration and by the founder effect highlights the importance of sensitiveness to the ecological environment and of fluctuations in group size, respectively. 相似文献
113.
国家公园效果评价体系研究 总被引:1,自引:0,他引:1
建立国家公园是保护生物多样性和促进地方发展的重要途径之一,开展国家公园效果评价是了解国家公园功能发挥的有效途径。通过查阅大量文献及德尔菲法(Delphi),确定了与国家公园效果相关的28个评价指标,同时以功能为主导,将评价指标归纳为5个功能指标群:保护功能指标群(7个评价指标)、科研功能指标群(6个评价指标)、游憩功能指标群(7个评价指标)、教育功能指标群(4个评价指标)和经济发展功能指标群(4个评价指标),通过对评价指标的赋分(5分制原则)和计算权重,从而达到国家公园效果评价的量化,实现对国家公园建设效果的评价。 相似文献
114.
Among primates, group size is highly variable. The standard ecological model assumes that better predation avoidance as group
size increases favours living in larger groups, whereas increased travel costs and reduced net food intake due to within-group
competition for resources set the upper limit. Folivorous primates, however, tend to defy this generalisation in that some
live in small groups despite low costs of feeding competition. To resolve this ’folivore paradox’, it has been suggested that folivore group size is limited by social factors such as male
harassment or infanticide, or that females can disperse more easily and thus maintain group size near optimum levels. In this
paper, we examine the effects of group size on home range size, day-journey length, activity budget and diet in wild Thomas’s
langurs (Presbytis thomasi), which live in one-male multi-female groups with a limited life cycle. We examined only data from the stable middle tenure
phase when factors such as the strength of the breeding male or the way in which groups were formed did not influence ranging
and activities. During this phase, group size affected day-journey length and home range size, and had a minor effect on diet,
but did not influence time spent feeding or resting, allogrooming or birth rates. Hence the upper limit to group size during
the middle tenure phase in Thomas’s langurs is not set by feeding competition. The folivore paradox is not due to frequent
female dispersal in Thomas’s langurs. The timing of female dispersal is not as expected if it serves to keep group sizes near
the ecological optimum, and groups seem to be below this optimum. Instead, female reproductive success is presumably maximised
in small to mid-sized groups because larger groups show a clear trend to experience higher risk of take-over, often accompanied
by infanticide. Because females can redistribute themselves among nearby groups when groups reorganise each time a new male
starts up a new group, females can keep the group small. Thus, a social factor, risk of infanticide, seems to provide the
selective advantage to small group size in Thomas’s langurs.
Received: 29 July 1999 / Revised: 17 November 1999 / Accepted: 15 October 2000 相似文献
115.
Indicators of visual scale as predictors of landscape preference; a comparison between groups 总被引:1,自引:0,他引:1
Tveit MS 《Journal of environmental management》2009,90(9):2882-2888
Landscape change alters the visual scale of agricultural landscapes, as production units get larger and strips of taller vegetation are removed between smaller units. Visual scale, defined as the perceptual units reflecting the experience of landscape rooms, visibility and openness, is considered a key factor shaping landscape preference. The visual expression of landscapes affects people in many ways; aesthetic appreciation, health and well being. In order to understand how landscape changes alter the visual scale of landscapes, and hence its effect on human beings, it is important to establish efficient and practical ways of measuring visual scale and its relation to landscape preferences. This paper presents an empirical test of the ability to predict landscape preference of two photo-based indicators of visual scale; percentage open land in the view and size of landscape rooms. A preference survey was conducted with two groups of respondents; a student group from the Norwegian University of Life Sciences (UMB) and a public group. The student group was chosen to represent future landscape professionals. Photos of landscapes varying in the expression of visual scale were shown to survey respondents, who were asked to give scores according to how much they liked the landscapes. Both indicators were found to be predictors of preference for the student group, but not for the public group. The results demonstrate that student preferences do not reflect the landscape preferences of the wider public. The different appreciation of visual scale in the landscape of future landscape professionals and the public implies that experts wanting to reflect preferences of the wider public should be cautious when evaluating the visual impact of landscape change. 相似文献
116.
The concept of “peak oil” has been explored and debated extensively within the literature. However there has been comparatively little research examining the concept of “peak minerals”, particularly in-depth analyses for individual metals. This paper presents scenarios for mined copper production based upon a detailed assessment of global copper resources and historic mine production. Scenarios for production from major copper deposit types and from individual countries or regions were developed using the Geologic Resources Supply-Demand Model (GeRS-DeMo). These scenarios were extended using cumulative grade-tonnage data, derived from our resource database, to produce estimates of potential rates of copper ore grade decline.The scenarios indicate that there are sufficient identified copper resources to grow mined copper production for at least the next twenty years. The future rate of ore grade decline may be less than has historically been the case, as mined grades are approaching the average resource grade and there is still significant copper endowment in high grade ore bodies. Despite increasing demand for copper as the developing world experiences economic growth, the economic and environmental impacts associated with increased production rates and declining ore grades (particularly those relating to energy consumption, water consumption and greenhouse gas emissions) will present barriers to the continued expansion of the industry. For these reasons peak mined copper production may well be realised during this century. 相似文献
117.
Mining with communities 总被引:2,自引:0,他引:2
Marcello M. Veiga Malcolm Scoble and Mary Louise McAllister 《Natural resources forum》2001,25(3):191-202
To be considered as sustainable, a mining community needs to adhere to the principles of ecological sustainability, economic vitality and social equity. These principles apply over a long time span, covering both the life of the mine and post-mining closure. The legacy left by a mine to the community after its closure is emerging as a significant aspect of its planning. Progress towards sustainability is made when value is added to a community with respect to these principles by the mining operation during its life cycle. This article presents a series of cases to demonstrate the diverse potential challenges to achieving a sustainable mining community. These case studies of both new and old mining communities are drawn mainly from Canada and from locations abroad where Canadian companies are now building mines. The article concludes by considering various approaches that can foster sustainable mining communities and the role of community consultation and capacity building. 相似文献
118.
Aggregation via pheromone signalling is essential for tree-killing bark beetles to overcome tree defenses and reproduce within hosts. Pheromone production is a trait that is linked to fitness, so high individual variation is paradoxical. One explanation is that the technique of measuring static pheromone pools overestimates true variation among individuals. An alternative hypothesis is that aggregation behaviour dilutes the contribution of individuals to the trait under selection and reduces the efficacy of natural selection on pheromone production by individuals. We compared pheromone measurements from traditional hindgut extractions of female southern pine beetles with those obtained by aerating individuals till they died. Aerations showed greater total pheromone production than hindgut extractions, but coefficients of variation (CV) remained high (60-182%) regardless of collection technique. This leaves the puzzle of high variation unresolved. A novel but simple explanation emerges from considering bark beetle aggregation behaviour. The phenotype visible to natural selection is the collective pheromone plume from hundreds of colonisers. The influence of a single beetle on this plume is enhanced by high variation among individuals but constrained by large group sizes. We estimated the average contribution of an individual to the pheromone plume across a range of aggregation sizes and showed that large aggregation sizes typical in mass attacks limit the potential of natural selection because each individual has so little effect on the overall plume. Genetic variation in pheromone production could accumulate via mutation and recombination, despite strong effects of the pheromone plume on the fitness of individuals within the aggregation. Thus, aggregation behaviour, by limiting the efficacy of natural selection, can allow the persistence of extreme phenotypes in nature. 相似文献
119.
以新疆天业集团化工园及其发展循环经济的下游企业——青松天业水泥有限公司为例,通过对企业内部的清洁生产工艺,企业间生态产业链的物质代谢、产业共生和效益集成分析,总结天业集团循环经济型化工产业的成功经验并对其存在问题提出对策建议,探索新疆未来循环经济型工业的发展模式和发展方向。 相似文献
120.
我国矿山开采类的项目较多,环境影响因素较多,环境影响程度大,因此对这类项目的环境管理,特别是项目的竣工验收是环境管理等部门的工作重点。近几年来,我国的相关法律法规变化较大,对竣工环保验收提出了新的要求,本文通过研究矿山开采项目的特点和法律法规的最新要求,总结出矿山类项目验收过程常见的问题,并提出改进措施。 相似文献