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431.
对溧水神仙洞的发掘和进行地质、地貌、孢粉、古脊椎动物与古人类、C14 年代及考古等多学科综合研究结果表明 :该洞是石炭系石灰岩沿层面裂隙经地下水溶蚀而成 ;洞穴堆积物的时代应属全新世早期 ,或新石器时代早期 ,绝对年代距今约为 1.1万年。其中发现的动物群为我国南方晚更新世动物群向现代动物群过渡的类型 ,而代表中 -晚更新世的最后鬣狗与代表新石器时代文化标志的陶片共生 ,为我国第四纪时代的划分 ,或新、旧石器时代文化的划分提供了重要依据。陶片则迄今为止是我国具有完整地层层位记录的最古陶片。它的发现 ,不仅将我国新石器时代文化大大推前 ,更为重写中华古史 ,校正“中华五千年文明”的提法 ,将中华文明追溯到一万年前并重排世界古文明位次增加了依据。同时 ,智人颞骨的发现 ,对长江中、下游古人类的研究 ,也提供了新的资料  相似文献   
432.
The bioeconomic analysis of endangered species without consumptive values can be problematic when analysed with density-dependent models that assume a fixed environment size. Most bioeconomic models use harvest as a control variable, yet when modelling non-harvestable species, frequently the only variable under control of conservationists is the quantity of habitat to be made available. The authors explore the implications of this in a model developed to analyse the potential population recovery of New Zealand’s yellow-eyed penguin. The penguin faces severe competition with man for the terrestrial resources required for breeding and has declined in population to perilously low levels. The model was developed to estimate the land use required for recovery and preservation of the species and to compare the results to current tourism-driven conservation efforts. It is demonstrated that land may serve as a useful control variable in bioeconomic models and that such a model may be useful for determining whether sufficient incentives exist to preserve a species. However, the model may generate less useful results for providing a specific estimate of the optimal allocation of land to such a species.  相似文献   
433.
Abstract:  Customary forms of resource management, such as taboos, have received considerable attention as a potential basis for conservation initiatives in the Indo-Pacific. Yet little is known about how socioeconomic factors influence the ability of communities to use customary management practices and whether socioeconomic transformations within communities will weaken conservation initiatives with a customary foundation. We used a comparative approach to examine how socioeconomic factors may influence whether communities use customary fisheries management in Papua New Guinea. We examined levels of material wealth (modernization), dependence on marine resources, population, and distance to market in 15 coastal communities. We compared these socioeconomic conditions in 5 communities that used a customary method of closing their fishing ground with 10 communities that did not use this type of management. There were apparent threshold levels of dependence on marine resources, modernization, distance to markets (<16.5 km), and population (>600 people) beyond which communities did not use customary fisheries closures. Nevertheless, economic inequality, rather than mean modernization levels seemed to influence the use of closures. Our results suggest that customary management institutions are not resilient to factors such as population growth and economic modernization. If customary management is to be used as a basis for modern conservation initiatives, cross-scale institutional arrangements such as networks and bridging organizations may be required to help filter the impacts of socioeconomic transformations.  相似文献   
434.
A review of wetland impacts authorized under the New Jersey Freshwater Wetlands Protection Act (FWPA) was conducted based on permitting data compiled for the period 1 July 1988 to 31 December 1993. Data regarding the acreage of wetlands impacted, location of impacts by drainage basin and watershed, and mitigation were analyzed. Wetland impacts authorized and mitigation under New Jersey's program were evaluated and compared with Section 404 information available for New Jersey and other regions of the United States.Under the FWPA, 3003 permits were issued authorizing impacts to 234.76 ha (602.27 acres) of wetlands and waters. Compensatory mitigation requirements for impacts associated with individual permits required the creation of 69.20 ha. (171.00 acres), and restoration of 16.49 ha (40.75 acres) of wetlands. Cumulative impacts by watershed were directly related to levels of development and population growth.The FWPA has resulted in an estimated 67% reduction [44.32 ha (109.47 acres) vs 136.26 ha (336.56 acres)] in annual wetland and water impacts when compared with Section 404 data for New Jersey. For mitigation, the slight increase in wetland acreage over acreage impacted is largely consistent with Section 404 data.Based on this evaluation, the FWPA has succeeded in reducing the level of wetland impacts in New Jersey. However, despite stringent regulation of activities in and around wetlands, New Jersey continues to experience approximately 32 ha (79 acres) of unmitigated wetland impacts annually. Our results suggest that additional efforts focusing on minimizing wetland impacts and increasing wetlands creation are needed to attain a goal of no net loss of freshwater wetlands.  相似文献   
435.
The United States Department of Energy is developing the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico for the disposal of transuranic wastes generated by defense programs. Because changes in climate during the next 10,000 years (10 ka) may affect performance of the repository, an understanding of long-term climate variability is essential for evaluating regulatory compliance. Fluctuations in global climate corresponding to glaciation and deglaciation of the northern hemisphere have been regular in both frequency and amplitude for at least 780 ka. Coolest and wettest conditions in the past have occurred at the WIPP during glacial maxima, when the North American ice sheet reached its southern limit roughly 1200 km north of the WIPP and deflected the jet stream southward. Average precipitation in southeastern New Mexico during the last glacial maximum 22-18 ka before present (BP) was approximately twice that of the present. Driest conditions (precipitation approximately 90% of present) occurred 6.5-4.5 ka BP, after the ice sheet had retreated to its present location. Wet periods of unknown duration have occurred since the retreat of the ice sheet, but none have exceeded glacial conditions. Global climate models suggest that anthropogenic climate changes (i.e., warming caused by an increased greenhouse effect) will not result in an increase in precipitation at the WIPP. The climate of the last glacial maximum is therefore suitable for use as a cooler and wetter limit for variability during the next 10 ka.  相似文献   
436.
ABSTRACT: Public awareness of the importance of protecting the nation's water supplies is growing. Recent studies have shown a substantial increase in the perceived value of protecting water supplies for future use. In the Northeast, much of the water supply comes from ground water. This paper examines three test cases, each with different approaches for using geographic information systems (GIS) for ground water protection planning. In Wellfleet, Massachusetts, build-out scenarios were used to support regulatory and land acquisition decisions for siting a public water supply well. In Hadley, Massachusetts, the focus was on a decision support model for septic suitability assessment in support of regulatory efforts and infrastructure expansion. For Cortland County, New York, an interactive graphic user interface was created to facilitate the manipulation and recombination of a large volume of data by county officials to target ground water pollution prevention efforts. As personal computers become more powerful and inexpensive, and GIS data become more readily available, community and county governments are turning to GIS as a tool for developing comprehensive resource protection plans. Once appropriate data are input, a GIS can effectively and efficiently be used to derive outcomes of various land use plans and regulations.  相似文献   
437.
ABSTRACT: Contamination of supplies by a wide variety of pollutants has long presented water managers with difficult problems. In the last fifteen years the issue of groundwater contamination has received a great deal of attention. Most work has focused on the source side of the problem. Questions have included: where do pollutants come from, how widespread is the problem, and what are the effects of the contaminants on human health and the environment? Very little work, however, has yet been done on the response side of this issue. Are water managers aware of water pollution problems (actual or potential) and their magnitude, and how well prepared are they to deal with contamination situations if they should develop? This paper reports results from a study of such questions for the southern New Jersey area. The study was intended to assess both the methodological and substantive issues involved in an empirical investigation of response capability. In addition to reporting methodological findings, the paper concludes that, while problem awareness is relatively high, actual preparedness and response capabilities are strikingly low.  相似文献   
438.
New technologies are characterized by various forms of incertitude that challenge both scientific expertise and regulatory action. In this paper, we argue that these incertitudes place experts in irreducible double bind situations, which may end in paralysis. Double binds emerge when primary injunctions are contradicted by secondary injunctions at a different logical level, which affects the interpretation of the primary injunction. Adequately addressing the challenges posed by new technologies requires phronesis, or pragmatic, context-dependent and action-oriented knowledge grounded in value deliberation. Using endocrine disruptors and carbon nanotubes as empirical examples, we argue that in relation to new technologies involving various kinds of incertitude, being phronimos—the person who can do phronesis—involves synthetically and simultaneously enacting parts of the three interrelated domains of knowledge, ethics and institutions, also across different logical levels. The special kind of experience-based phronesic skill that required in the regulatory appraisal of new technologies is thus fundamentally related to the human capacity of pattern recognition. Finally, we argue that being aware of and making full use of practical wisdom thus conceptualized enables a new operationalization of the precautionary principle.  相似文献   
439.
ABSTRACT: New Zealand is one of the first countries in the world to enshrine the concept of watershed management in law, through institutional arrangements and the Resource Management Act of 1991 ‐ a law constructed on a watershed management legacy begun in 1941. This paper outlines the development of New Zealand's Resource Management Act (as it applies to water management) and the lessons that have been learned in its implementation.  相似文献   
440.
天津滨海新区生态系统服务评估及空间分级   总被引:1,自引:1,他引:0       下载免费PDF全文
采用提出的“功能当量”相对评估模型,并以RS和GIS为技术平台对2009年天津滨海新区生态系统服务功能进行评估,采用区域网格化空间表达,对研究区进行分级研究.结果表明,滨海新区生态系统单位面积服务功能当量大小依次为湿地、水体、林地、草地、耕地、裸地;2009年滨海新区生态系统服务功能当量总和为1068680.13,III级以上功能当量的单元格比例为71.22%,总体处于较高水平;通过与价值量法结果对比,得出利用“功能当量”相对评估模型对研究区的评估结果与价值量法的评估结果具有显著相关性,证明该评估模型的可行性和合理性.  相似文献   
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