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根据新疆维吾尔自治区2016年水资源统计数据,引入洛伦兹曲线和基尼系数,通过绘制水资源与耕地、人口及第二产业产值的洛伦兹曲线并计算其基尼系数,分析新疆水资源的空间匹配性。结果显示:新疆水资源与耕地、人口、第二产业产值的空间匹配基尼系数分别为0.453、0.4596、0.6898,匹配程度处于差或很差水平。在此基础上,提出优化水资源空间匹配度,科学规划水资源利用的对策建议。 相似文献
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<正>当前,安徽省现有水资源因子与经济社会因子在空间中的匹配关系的研究尚是空白,本文通过基尼系数、不平衡指数等方法对于安徽省水资源在空间中的均衡程度进行识别,进而分析安徽省水资源空间均衡今后面临的发展情形。一、基于基尼系数的水资源空间均衡评价(一)洛伦兹曲线洛伦兹曲线是计算收入最低任意百分比人口所占的收入百分比来表示人口累计百分比和收入累计百分比之间对应关系的曲线。(二)构建洛伦兹曲线本文选取安徽省2018年统计年鉴中各地市的水资源因子(水资源总量、用水总量)、经济因子(耕地面积、人口数量和第二产业GDP)等数据,步骤如下:(1)将安徽省17个地市数据作为研究样本,水资源因子作为基本匹配原象,选取耕地面积(人口数量、第二产业GDP)作为匹配对象。 相似文献
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《人民黄河》2021,43(9)
为定量评价研究区及其子区域的水资源空间均衡程度、分析水资源空间均衡的分布特征,针对基尼系数无法单独评价子区域均衡性的问题,提出基尼系数和联系数相结合的水资源空间均衡评价模型。该模型在应用洛伦兹曲线计算得到基尼系数的基础上,通过分级分区,采用联系数计算反映研究区隶属于均衡、临界均衡、不均衡3个不同空间均衡等级的隶属度,再结合减法集对势对脆弱性子区域进行诊断识别。将该模型应用于安徽省水资源空间均衡评价中,分别对16个地市的人口与水资源、GDP与水资源的空间均衡状况进行差异性分析。结果表明:安徽省2011—2018年人口、GDP与水资源量的基尼系数高于国际警戒线0.4,长期处于较不均衡和不均衡状态;水资源空间均衡状况从南向北逐渐变差;2018年安徽省水资源空间均衡脆弱性区域有合肥、淮北、亳州、宿州、蚌埠、阜阳、淮南、马鞍山、芜湖、铜陵10个地市,这些地市应作为水资源空间均衡的主要调控对象。 相似文献
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为了分析邯郸市水资源在空间分配上的公平性问题,通过Matlab软件积分求解基尼系数,应用基尼系数分析水资源与耕地、第二产业和人口的匹配程度。结果表明,邯郸市水资源与耕地、第二产业总产值和人口的空间匹配基尼系数分别为0.4548,0.3244,0.4971。依据联合国对基尼系数的划分标准,邯郸市水资源匹配度处于较差或一般水平,即该市水资源空间分配公平度较差。在未来水资源的优化配置过程中,相关部门应注意水资源空间匹配的合理性问题和统筹规划,以提高水资源利用效率。 相似文献
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为系统分析和精准量化地级市水资源与经济社会发展匹配特征,选取水资源总量、用水量和人口、GDP、耕地面积等典型要素,提出同时运用基于基尼系数和基于数列的匹配度计算方法进行量化研究的思路,以沙颍河沿线10个地级市为例,定量分析了其2009—2018年水资源与经济社会发展的时空匹配关系。结果表明:两种方法能够同时从整体时间/空间和单个地级市/时段的角度对水资源和经济社会两系统要素的匹配问题进行全面研究;各地级市时间基尼系数存在些许差异,但不同要素匹配程度基本一致且结果均较好;除水资源总量-GDP、用水量-GDP的时间匹配度呈现低—高—低的演进态势,其他要素的匹配度随时间呈现波动变化趋势;空间基尼系数在时间尺度上变化幅度不大,但不同匹配要素之间差异显著;空间匹配度在时间上基本保持一致,部分地级市匹配结果较差,尤以郑州、南阳和驻马店的问题最为突出。 相似文献
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为查明喀什地区近年来用水结构及变化趋势,在获取2016—2019年各行业用水量及占比的基础上,运用区位熵、洛伦兹曲线及基尼系数等方法分析喀什地区近年来用水结构变化特征及水资源用水水平.结果表明:近年来喀什地区各行业用水存在一定的不合理性,用水效率较低;具体表现为农业用水空间分布特征高度平均差异性较小,生活用水空间分布的... 相似文献
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根据冗各电站地下厂房开挖支护的施工顺序,以隐式杆单元模拟锚杆,以壳单元模拟混凝土喷层,采用三维非线性有限元技术,对洞室群的开挖支护动态过程进行了模拟计算。通过三维非线性有限元计算分析得到:洞室群动态开挖过程中围岩应力变形的分布规律,围岩塑性区的发展规律,锚杆受力变化情况。计算结果表明:整个开挖过程中,洞周围岩位移变化规律正常,量值较小,塑性区主要分布在洞室周边,围岩稳定性较好;但在洞室交叉口处围岩的变形较大,出现较大范围的塑性区,在此基础上提出了支护措施优化方案,并对优化方案的效果进行了评价。 相似文献
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The relocation of unionacean mussels is commonly used as a conservation and management tool in large rivers and streams. Relocation has been used to recolonize areas where mussel populations have been eliminated by prior pollution events, to remove mussels from construction zones and to re-establish populations of endangered species. More recently, relocation has been used to protect native freshwater mussels from colonization by the exotic zebra mussel Dreissena polymorpha. We conducted a literature review of mussel relocations and evaluated their relative success as a conservation and management strategy. We found that 43% of all relocations were conducted because of construction projects that were forced to comply with the Endangered Species Act 1973 and that only 16% were monitored for five or more consecutive years. Most (43%) relocation projects were conducted from July to September, presumably a period when reproductive stress is relatively low for most species and the metabolic rate is sufficient for reburrowing in the substrate. The mortality of relocated mussels was unreported in 27% of projects; reported mortality varied widely among projects and species and was difficult to assess. The mean mortality of relocated mussels was 49% based on an average recovery rate of 43%. There is little guidance on the methods for relocation or for monitoring the subsequent long-term status of relocated mussels. Based on this evaluation, research is needed to develop criteria for selecting a suitable relocation site and to establish appropriate methods and guidelines for conducting relocation projects. 相似文献
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In the lower River Murray, Australia, populations of gastropods have declined markedly over the past 40 years. Of the native fauna of about 18 species, only the ancylid Ferrissia petterdi remains common (but in patches), and another five species feature in sporadic local resurgences. Until recently the viviparid Notopala was thought to be extinct. The introduced physid Physa acuta is widespread, but in low numbers. The decline probably is associated with flow regulation, high turbidity and the introduction of common carp. Snail populations have persisted, however, in irrigation pipelines fed from the river, where they periodically cause blockages. This paper reports the discovery of the only known populaion of Notopala hanleyi in a pipeline where the inner wall accumulates microbial and other organic matter, providing high quality food for snails. In the Murray before regulation most of the periphytic biomass was probably microbial, as fluctuating water levels would have maintained littoral communities in a highly productive, early state of succession his postulated that, by stabilizing seasonal water levels, regulation has promoted the production of filamentous green algae, an inferior food source, and so displaced snail populations from the open aquatic environment. 相似文献
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V. K. Konovalov O. V. Yashkin V. V. Ermakov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2008,42(2):105-109
A system for removal and pneumatic transport of fly ash is examined, in which air pulses act on batches (pistons) of ash formed
in a duct. Studies are made of the effect of several physical parameters on the force required to displace a piston of ash
and these serve as a basis for choosing a system for removal and pneumatic transport of ash simultaneously from several hoppers
of an electric precipitator. This makes it possible to separate the ash particles according to size without introducing additional
components. Formulas are given for calculating the structural and dynamic parameters of this system and measurements of indirect
dynamic parameters are used to calculate the input-output characteristics of the system. In order to optimize the system,
configurations for summing several ducts into a single transport duct for pneumatic ash transport are proposed. Some variants
of dry ash utilization and the advantages of producing of size-separated particles are considered.
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Translated from élektricheskie Stantsii, No. 2, pp. 26–30 (2008). 相似文献
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Peter B. Bayley 《河流研究与利用》1991,6(2):75-86
The ‘flood pulse advantage’ is the amount by which fish yield per unit mean water area is increased by a natural, predictable flood pulse. Evidence for this increase is presented from tropical and temperate fisheries. It is argued that increasing multispecies fish yield by restoring the natural hydrological regime is consistent with increasing production of other trophic levels and with restoration from ecological and aesthetic viewpoints. When applied to a river-floodplain system, this restoration would provide a large, self-sustaining potential for recreation, commercial exploitation, and flood control. An interim ‘natural flood pulse’ restoration approach is proposed for systems modified for navigation. This approach approximates the natural hydrological regime in a river reach and is intended as a first step in the long process of restoring the watershed. 相似文献
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简述天湖水电站投运以来各种故障的表现形式,分析其原因,提出了相应的处理方法及措施,并对合理利用国内外设备提出建议。 相似文献