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941.
中国地震应急二级分区的初步研究 总被引:1,自引:0,他引:1
在已有地震应急宏观分区研究的基础上,首先讨论了进一步开展地震应急次级分区的意义及其分区方案的多样性;然后提取“政治经济强辐射中心、少数民族聚居区、贫困人口聚居区、侨乡、大型工业危险源”等5方面社会经济因素在不同县域内的10种主要组合类型作为区划指标,采取“自下而上归并”的区划途径,进行了中国地震应急二级分区研究。结果表明,在将我国大陆划分为8个地震应急一级大区的基础上,从社会经济角度又可大致划分出19个二级区;二级区的划分进一步揭示了不同地区开展地震应急工作时应注意的一些较具体的社会经济问题及其空间配置特点;两级分区的结合从“宏观概括”和“中观具体”两个层次示范了地震应急分区研究的基本内容。 相似文献
942.
Globally, rural regions are searching for innovative growth opportunities to reinvigorate their economies. This paper examines the redevelopment of rural communities through an ecological lens – based on the notion of continuous cycles of adaptive change within complex systems as first identified within Holling’s concept of panarchy. Panarchy suggests that complex systems have more than a single equilibrium point and, instead, have some inherent resiliency based on the notion of multiple stable regimes. As such, panarchy provides a conceptual model that describes the ways in which complex social and ecological systems are organized and structured both spatially and temporally. By drawing parallels between the characteristics of ecological communities and rural economic systems, a novel framework is developed to assist policy-makers reflect on a rural community’s position along its own adaptive change cycle and, then, implement appropriate inventions to improve system resiliency – which in this case is linked with economic resiliency through development and/or growth. Supported by empirical data emerging from both key informant interviews and content analysis of current rural development policy, this work also identifies leverage points where policy intervention may be most advantageous by specifying the timing of policy instruments on the cycle. Specifically, this framework describes four leverage points, three major and one minor, to help push or pull rural regions into an area of higher resilience. 相似文献
943.
944.
Ruth R. Brockman Carmen T. Agouridis Stephen R. Workman Lindell E. Ormsbee Alex W. Fogle 《Journal of the American Water Resources Association》2012,48(2):391-406
Brockman, Ruth R., Carmen T. Agouridis, Stephen R. Workman, Lindell E. Ormsbee, and Alex W. Fogle, 2012. Bankfull Regional Curves for the Inner and Outer Bluegrass Regions of Kentucky. Journal of the American Water Resources Association (JAWRA) 48(2): 391‐406. DOI: 10.1111/j.1752‐1688.2011.00621.x Abstract: Bankfull regional curves that relate channel dimensions and discharge to watershed drainage area are useful tools for assisting in the correct identification of bankfull elevation and in stream restoration and reconstruction. This study assessed 28 stable streams located in two physiographic regions of Kentucky: the Inner Bluegrass and the Outer Bluegrass. Bankfull channel dimensions, discharge, and return period as well as average channel slope, median bed material size, sinuosity, Rosgen stream classification, and percent impervious area were determined. Significant relationships were found between drainage area and the bankfull characteristics of cross‐sectional area, width, mean depth, and discharge for both the Inner Bluegrass and Outer Bluegrass regions (α = 0.05). It was also found that the percent impervious area in a watershed had minimal effect on bankfull dimensions, which is attributed to the well‐vegetated nature of the streambanks, cohesive streambank materials, and bedrock control. No significant differences between any of the Inner Bluegrass and Outer Bluegrass regional curves were found (α = 0.05). Comparisons were made between the Inner Bluegrass and Outer Bluegrass curves and others developed in karst‐influenced areas in the Eastern United States. Although few significant differences were found between the regional curves for bankfull discharge and width, a number of the curves differed with regards to bankfull cross‐sectional area and mean depth. 相似文献
945.
Jessica Haucke Katherine A. Clancy 《Journal of the American Water Resources Association》2011,47(6):1338-1347
Haucke, Jessica and Katherine A. Clancy, 2011. Stationarity of Streamflow Records and Their Influence on Bankfull Regional Curves. Journal of the American Water Resources Association (JAWRA) 47(6):1338–1347. DOI: 10.1111/j.1752‐1688.2011.00590.x Abstract: Bankfull regional curves, which are curves that establish relationships among channel morphology, discharge, drainage area, are used extensively for stream restoration. These curves are developed upon the assumption that streamflows maintain stationarity over the entire record. We examined this assumption in the Driftless Area of southwestern Wisconsin where agricultural soil retention practices have changed, and precipitation has increased since the 1970s. We developed a bankfull regional curve for this area using field surveys of bankfull channel performed during 2008‐2009 and annual series of peak streamflows for 10 rivers with streamflow records ranging from the 1930s to 2009. We found bankfull flows to correlate to a 1.1 return period. To evaluate gage data statistics, we used the sign test to compare our channel morphology to historic 1.5 return period discharge (Q1.5) for five time periods: 1959‐1972, 1973‐1992, 1993‐2008, 1999‐2008, and the 1959‐2008 period of record. Analysis of the historic gage data indicated that there has been a more than 30% decline in Q1.5 since 1959. Our research suggests that land conservation practices may have a larger impact on gaging station stationarity than annual precipitation changes do. Additionally, historic peak flow data from gages, which have records that span land conservation changes, may need to be truncated to represent current flow regimes. 相似文献
946.
泥石流分布密度是区域泥石流危险度评价的主要指标。泥石流分布密度分为点密度和面密度,前者是指每103km内泥石流沟的数量;后者是指每103km内泥石流沟的流域面积。以川西山区60个县市区为研究样本,分别以泥石流点密度和面密度作为区域泥石流危险度的主要评价指标,结合7个相同的区域泥石流危险度的次要评价指标,对研究区以县市区为基本单元的区域泥石流危险度进行了定量评价。结果表明,各县市区面积加权平均后的泥石流危险度分别为0.51(面密度)和0.52(点密度),差别甚微,整体上均属于泥石流中度危险区。两者的平均绝对差值0.04,远小于0.2这一危险度等级差值,平均相对差值为6.49%,小于10%这一允许的均方差范围。由此可知,用泥石流面密度来评价区域泥石流危险度,并非优于点密度;相反地,由于泥石流点密度具有获取资料相对容易、计算比较简便、工作量较小等优点,因而具有更为便利的推广应用价值。 相似文献
947.
目前化工行业及化学工业园区的安全准入主要依据是现行的法律、规范和标准,而化学工业及化工园区的飞速发展使得现有的规范、标准等存在严重地滞后性,远远不能满足化工园区区域安全准入及风险承载核算的要求。论文针对化工园区目前建设及发展状况,主要分析化工园区安全准入的内涵、现存状况及存在的局限性,构建化学工业园区规划及企业安全准入的基本理论框架,研究思路从化学工业园区的定性、定量风险着手,阐述准入的具体步骤、关键把握的重点以及风险承载状况,并针对国外的风险容许标准,确定适合我国化工园区的风险准入准则,最后提出下一步的研究重点,对指导我国目前化工园区安全准入具有一定的理论和现实意义。 相似文献
948.
采用复合指标方法对辽宁省14个省辖市的城市化发展水平进行了测度.结果表明,辽宁省内城市化发展水平呈现高低落差大的格局.根据测度结果进行城市化发展水平类型划分,探讨了影响城市化发展水平区域差异的驱动力,主要包括资源禀赋因素、经济因素、经济全球化因素、城市基础设施因素、历史和政策因素. 相似文献
949.
950.
作为海滨旅游和生态旅游的有机结合,海滨生态旅游不仅是对海洋资源的合理利用,也是可持续发展理念在旅游业中的实践应用.以山东沿海地区为例,运用区域合作的相关原理构建了海滨生态旅游区域合作的动力机制和合作机制,从产品开发、市场开发、信息网络建设三个方面论证了实现路径,并从加强合作保障、促进利益协调和消除地区壁垒三个方面提出了对策. 相似文献