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941.
AbstractThe seasonal flood-limited water level (FLWL), which reflects the seasonal flood information, plays an important role in governing the trade-off between reservoir flood control and conservation. A risk analysis model for flood control operation of seasonal FLWL incorporating the inflow forecasting error was proposed and developed. The variable kernel estimation is implemented for deriving the inflow forecasting error density. The synthetic inflow incorporating forecasting error is simulated by Monte Carlo simulation (MCS) according to the inflow forecasting error density. The risk analysis for seasonal FLWL control was estimated by MCS based on a combination of the forecasting inflow lead-time, seasonal design flood hydrographs and seasonal operation rules. The Three Gorges reservoir is selected as a case study. The application results indicate that the seasonal FLWL control can effectively enhance flood water utilization rate without lowering the annual flood control standard.
Editor D. Koutsoyiannis; Associate editor A. ViglioneCitation Zhou, Y.-L. and Guo, S.-L., 2014. Risk analysis for flood control operation of seasonal flood-limited water level incorporating inflow forecasting error. Hydrological Sciences Journal, 59 (5), 1006–1019. 相似文献
942.
知识经济时代的区域资源环境研究 总被引:11,自引:0,他引:11
知识经济时代正逐步向我们走来。本文主要从知识经济时代来临之际的区域资源环境研究入手,论述资源环境观念的创新,区域特点、区域综合评价、区域可持续发展的内涵的改变。阐述了区域资源环境的研究在面向知识经济时代、建设国家创新体系之际,应该着手的两大任务:一个是区域资源环境的研究在建设国家创新体系中所能发挥的作用,即区域资源环境研究对建设国家创新体系的贡献;另一个是区域资源环境研究在国家创新体系中自身的创新,即是区域资源环境研究本身的创新。 相似文献
943.
Indigenous knowledge is a multilayered knowledge system that can inform contemporary management in both natural observations and cultural value. Centuries old observations preserved within song, chant, and story has been globally recognized as a resource to integrate with conservation efforts for endangered species. In the case of the endemic land snails, kāhuli, of the Hawaiian archipelago, there is a prominent cultural presence preserved in oral tradition and written records in 19th and early 20th century’s Hawaiian language newspapers. As we witness the dramatic decimation of one of the greatest models of species radiation, the unveiling of the repositories of indigenous knowledge is crucial for conservation of these endemic land snails. This paper reports on indigenous knowledge that informs about the cultural significance (i.e., poetic device, metaphorical role, importance to hula) and ecology of kāhuli, and how indigenous knowledge can contribute to conservation efforts of rare and endangered species. 相似文献
944.
Piran C L White Steve Cinderby Dave Raffaelli Annemarieke de Bruin Alison Holt Meg Huby 《Area》2009,41(4):414-424
There has been much debate about the importance of policy-relevant research in geography over the last decade. There has also been an increasing recognition by policymakers of the importance of integrative (interdisciplinary and transdisciplinary) approaches to policy-relevant research. However, geographers have been more reluctant than their colleagues in other social and natural sciences to embrace integrative research collaborations. For integrative research to achieve its full potential and to encourage greater participation from the geographical research community, we need to increase our understanding of its potential value, but also some of the challenges that it poses, and how these can be overcome. In this paper, we consider the processes involved in conducting successful integrative research from the perspective of researchers involved in these projects. We base our analysis on the results of a questionnaire survey of international integrative research programmes on environmental issues in rural areas, combined with our own experiences of working in integrative research. We conclude that effective integrative research depends on the establishment of a clear conceptual framework, the use of appropriate temporal and spatial scales in the research, effective language and communication, time and commitment, and trust and respect. We also highlight the value of stakeholder involvement in integrative research to ensure the policy relevance of the work and provide a mechanism to assist with effective knowledge transfer of the results. 相似文献
945.
Ryan K Danby David S Hik D Scott Slocombe† Andrew Williams‡ 《The Geographical journal》2003,169(3):191-204
The past, present, and future contributions of science in the St Elias Mountains, and its relationship with regional development, resource management, and traditional ecological knowledge is examined. Science has evolved from an early foundation of exploration, through stages of resource inventories and surveys, to deductive scientific research and, more recently, a promising reconnection with traditional knowledge. Directly and indirectly, events such as the Klondike Gold Rush, construction of the Alaska Highway, creation of the Arctic Institute of North America's Kluane Lake Research Station, and establishment of protected areas have helped foster scientific activities in the region. In turn, this scientific perspective has influenced regional development by providing detailed information that has been utilized, to varying degrees, in resource use, planning, and decisionmaking. Over the past decade, management of the region has become less sectoral and more cooperative in nature, due partly to the implementation of co-management agreements, regional land use planning, and settlement of first nations' land claims. Incorporating both science and traditional knowledge into this process through collaborative endeavours such as long-term ecological monitoring, adaptive management, and information integration will contribute to ecosystem-based management of the St Elias and ensure that both perspectives play an integral role in sustainable development of the region. 相似文献
946.
947.
Kolguev Island in the Russian Arctic has a unique tundra ecosystem and an indigenous Nenets population whose livelihood is traditionally based on reindeer herding. The Nenets faced a major crisis in 2013–2014 when the reindeer population collapsed. Widely different explanations for this collapse were put forward. This lack of a shared perspective points at the failure of genuine joint knowledge production (JKP) in the island’s UNEP–GEF’s ECORA project (2004–2009). The ECORA project aimed to achieve integrated ecosystem management by stimulating dialog and mutual learning among indigenous people, state agencies, and scientists. This paper analyses the failure of ECORA’s JKP, using a recently developed framework of conditions for successful JKP. The results suggest that ECORA met none of these conditions. It failed at bringing the scientific and indigenous knowledge systems together, and the produced knowledge did not resonate with indigenous people’s perception of living in Kolguev. 相似文献
948.
从总结陆相侏罗-白垩纪地层界线的研究成果和工作方法,结合国际地层委员会“修订准则”和国际地层指南的规定,论述了建立“陆相层型”的紧迫性、理论和方法。我国陆相地层极为发育,但研究明显滞后于海相地层,主要问题是缺乏划分对比标准。目前以海相地层研究建立的层型尚不能应用于陆相地层,况且一些地质断代还未建立层型。陆相地层研究要先建立自己的标准。与海相地层比较,陆相地层在同位素测年、磁性地层划分和事件地层学研究方面具备建立层型的优势,同样可以找到分布广泛和利于大范围地层对比的化石门类。建立陆相层型的关键是找到沉积连续、化石丰富和暴露完全的剖面。陆相层型可以“单位层型”与“界线层型”建立并举,有条件的地质断代还是要重视建立“界线层型”。生物地层学研究一定要以恢复演化谱系或发生序列为基础,界线化石标志应该选在其“首现”层位。“陆相层型”的建立应强调多学科、多门类、多方法的综合研究。 相似文献
949.
三维流形单元的生成是进行三维数值流形分析的首要问题之一。详细研究了三维流形单元的生成过程,并采用C++语言编写了相应的程序。借鉴二维流形单元的形成技术,基于拓扑学的“有向性”原理,将点、有向边、有向环、有向面和有向壳等作为三维块体的基本数据结构。将材料体和数学网格进行布尔交运算,并对形成的流形块体进行有效性检测,满足要求后即形成新的三维流形单元。每个数学网格的顶点作为新流形单元的数学覆盖,再对数学覆盖进行细分,形成流形单元的物理覆盖。分别选取凹形体、空心体和包含有限结构面的材料体与数学网格进行布尔交运算,并选取一个典型工程来检查该方法和程序的可行性。计算结果表明,该方法可以对复杂块体(凹形体、空心体和包含有限结构面的体)进行处理,为今后进行复杂结构计算和分析奠定基础,具有较强的适应性和可靠性。 相似文献
950.
澜沧江-湄公河流域汛期洪灾频发,气候变化极有可能进一步加剧该区域洪水的量级和发生频率,需要上下游合作共同应对。建立了澜沧江-湄公河全流域分布式水文及水库调度模型,模拟1991-2005年全流域13条支流和5个干流防洪控制断面的逐日天然流量过程,在此基础上模拟全流域已建、在建和规划水库的联合调度过程,分析防洪作用。结果表明:①全流域水库联合调度对湄公河5个主要断面均有显著的防洪作用,在完全按照防洪目标对水库进行调度的情况下可将200年一遇洪水减至20~50年一遇。②湄公河左岸支流的防洪能力远高于右岸,具有较高防洪能力的支流有澜沧江、南乌河、南俄河、南屯河、濛河、色公河和桑河。③对不同断面起主要防洪作用的支流不同:在琅勃拉邦上游,澜沧江、南乌河起主要作用;在那空帕农断面,南俄河与南屯河加总的防洪作用与澜沧江基本相等;在巴色下游,濛河和色公河的作用均超过澜沧江。澜湄合作机制为上下游防洪合作提供了重要契机,研究成果可为流域国协商建立联合防洪调度机制提供参考。 相似文献