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131.
Some flint lithic artifacts were discovered in the fissure fillings of the well-known Pirro Nord site (Apulia, Southern Italy). The lithic industry, composed by three cores and some flakes, has been found to be associated to an Early Pleistocene vertebrate fossil assemblage. The fossil association contains a wide range of micromammals, including Allophaiomys ruffoi and Episoriculus gibberodon and large mammals including Bison degiulii and Equus altidens together with African elements as the gelada baboon Theropithecus and the saber-toothed cat Megantereon whitei. It defines the latest Villafranchian chronological unit (Pirro Nord Faunal Unit) in the Western European mammal biochronology. The lithic industry of Pirro Nord represents the oldest occurrence of the genus Homo in Europe as it is attributable to a chronological interval between 1.3 and 1.7 Ma. This supports the hypothesis that the genus Homo, with Oldowaian technology, extended its range in Europe, probably from western Asia, during the first half of the Early Pleistocene. The new discovery from Pirro Nord changes the chronology of the first arrival of hominids in Europe and offers new perspectives in the debate about the human dispersal in the Early Pleistocene.  相似文献   
132.
为了掌握伊犁伊宁矿区矿井水水质现状,采用模糊综合评价法对矿井水水质进行评价,结果表明:伊南矿区未经采煤扰动的地下水水质和矿井水水质都较好,说明煤矿开采对地下水水质影响不大;伊北矿区矿井水由于矿化度背景浓度值高,水质较差。此次评价为伊犁伊宁矿区矿井水综合利用提供了科学依据。  相似文献   
133.
The paper presents a methodology that guided several ethnoentomological research projects and goes on to examine and compare the results from two independent research locations in Asia. The first location is in the Philippines, a Green Revolution area that has been heavily impacted by extension messages and insecticide use. The second location is in Nepal which has a traditional subsistence orientation and has remained widely unaffected by agricultural modernization. The paper emphasizes the differences and similarities of the results from the two sites and discusses the role of the methodology and methods used in capturing ethnoentomological knowledge, particularly with regard to insect pests in rice. The results of both investigations share the importance of agronomic criteria among farmers in insect classification and sorting criteria, thus highlighting the relevance of functional criteria. Farmers at both research sites have difficulties in identifying the lifecycles of insects. We discuss the issues of tradition and change in farmer entomological knowledge and providing support to the knowledge base of farmers though programs like IPM-Farmer Field Schools as opposed to broad-based recommendations for crop pest management.Article type: MS-ENVI-SI ETHNOSCI MS04 Contribution to Environment, Development & Sustainability, special issue ‘Bridging the gap between natural resources and their human management for the future using ethnoscience’.  相似文献   
134.
早始新世气候适宜期发生在53?—?51 Ma,是新生代早期一段气候持续温暖时期.与中中新世气候适宜期和上新世气候适宜期相比,早始新世气候适宜期更加温暖.对于该时期驱动机制的理解有助于深入认识未来温暖气候状况的变化.本文总结了前人提出的构造尺度气候变化的假说,推断出早始新世气候适宜期可能是由于板块构造活动变化导致的温室气体变化所造成,而星际暗物质变化对早始新世气候适宜期的影响有待进一步评估.  相似文献   
135.
Current “business as usual” projections suggest greenhouse gas emissions from industrialized nations will grow substantially over the next decade. However, if it comes into force, the Kyoto Protocol will require industrialized nations to reduce emissions to an average of 5% below 1990 levels in the 2008–2012 period. Taking early action to close this gap has a number of advantages. It reduces the risks of passing thresholds that trigger climate change “surprises.” Early action also increases future generations' ability to choose greater levels of climate protection, and it leads to faster reductions of other pollutants. From an economic sense, early action is important because it allows shifts to less carbon-intensive technologies during the course of normal capital stock turnover. Moreover, many options for emission reduction have negative costs, and thus are economically worthwhile, because of paybacks in energy costs, healthcare costs, and other benefits. Finally, early emission reductions enhance the probability of successful ratification and lower the risk of noncompliance with the protocol. We discuss policy approaches for the period prior to 2008. Disadvantages of the current proposals for Credit for Early Action are the possibility of adverse selection due to problematic baseline calculation methods as well as the distributionary impacts of allocating a part of the emissions budget already before 2008. One simple policy without drawbacks is the so-called baseline protection, which removes the disincentive to early action due to the expectation that businesses may, in the future, receive emission rights in proportion to past emissions. It is particularly important to adopt policies that shift investment in long-lived capital stock towards less carbon-intensive technologies and to encourage innovation and technology development that will reduce future compliance costs.  相似文献   
136.
This paper examines the ways residents in the Grampians area in the Australian state of Victoria used their local and their state and national based media before, during and after the 2006 bushfires (wildfires). The researchers were particularly concerned to understand how residents evaluated media sources as trustworthy and credible in relation to bushfire warnings and information about the fires delivered in the media.Analysis of data derived from two separate focus group sessions conducted by the researchers reveals four main themes. (1) The media are perceived as part of a broader information gathering process. (2) Local knowledge is the most important aspect in broadcast information. (3) Members of small communities can feel disenfranchised and resentful of the media when media coverage focuses on larger towns, and (4) the effects of media reporting, including specific warnings, are both immediate and long lasting.The paper explores some of the tensions that result from the ways rural residents use and distinguish between local/regional and metropolitan and out-of-state bushfire information; and it encourages better use of the local/regional media to increase community safety and awareness in relation to bushfire mitigation, preparedness and crisis management issues before, during and after the fires. It is suggested that risk communications professionals need to understand that when mediated risk-related communications are provided, a key evaluative criterion is whether or not those media and the messages represent and reflect local knowledge.  相似文献   
137.
The flood defence agency in England and Wales has been pursuing a programme of flood warning system enhancement, engaging householders at risk in improving their warning responses. The immediate aim of this paper is to test and revise a model of economic benefits of warnings, but the survey data also generate insights into the constraints acting upon flood warning responses. Damage saving is less than previously anticipated: warning reliability and householder availability problems limit savings. Warnings are less likely to be received by those in lower social grades, and flood warning lead time is a factor in avoiding damage. The survey data indicate the complexities involved in improving flood warning response, and provide policy pointers.  相似文献   
138.
Risk communication in flood incident management can be improved through developing hydrometeorological and engineering models used as tools for communicating risk between scientists and emergency management professionals. A range of such models and tools was evaluated by participating flood emergency managers during a 4-day, real-time simulation of an extreme event in the Thamesmead area in the Thames estuary close to London, England. Emergency managers have different communication needs and value new tools differently, but the indications are that a range of new tools could be beneficial in flood incident management. Provided they are communicated large model uncertainties are not necessarily unwelcome among flood emergency managers. Even so they are cautious about sharing the ownership of weather and flood modelling uncertainties.  相似文献   
139.
青海省牧区雪灾预警模型研究   总被引:4,自引:0,他引:4  
王江山  赵强 《灾害学》1998,13(1):30-33
对青海省牧区各气象站的积雪深度、积雪日数等气象资料进行了统计分析,结合青海省牧区积雪状况和草场特点,建立了雪灾预警模型。  相似文献   
140.
环境价值评估方法   总被引:8,自引:0,他引:8  
环境价值评估是环境管理科学化的基础。本文就迄今为止的国内外定价技术进行了综述并筛选出一套适合我国国情的价值评估体系、方法。  相似文献   
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