| 摘要: |
| 【目的】对生态水文联系分区以表征不同空间范围内的变异情势，进而为流域生态水文联系的良性维持提供理论支撑。【方法】统计渭河流域21个站点水文序列的水文改变指标（IHA），应用变化范围（Range of Variability Approach，RVA）法对其不同时间段的生态水文联系改变程度进行评估，并分析其空间分布规律。基于IHA构建分区指标体系，依据不同站点的生态水文联系变异程度，运用层次聚类法进行分区，并与主成分分析结果进行对比以验证其合理性。【结果】依据渭河流域内各站点的生态水文联系变异情况，将渭河流域划分为强烈变异区、中度变异区与轻度变异区3个变异区，不同分区可反映其生态水文联系综合变异的变异情势。根据各分区内的主导变异成分，可将3个分区再细化成5个变异小区，在强烈变异区中，将高、低脉冲流量和丰水期流量为主导变异成分的站点划为强烈变异区Ⅰ，极端流量和流量变化率为主导变异成分的站点划为强烈变异区Ⅱ；在中度变异区中，将高、低脉冲流量和流量变化率为主导变异成分的站点划为中度变异区Ⅰ，将最小极端流量、高脉冲流量和丰水期流量为主导变异成分的站点划为中度变异区Ⅱ；由于轻度变异区各主导变异成分均较轻，故未进一步细分。基于层次聚类法的生态水文联系的变异分区结果较为合理，与主成分分析结果基本吻合。【结论】各变异分区可表征不同分区的综合变化强度和主导变异成分，通过该分区可基本了解渭河流域不同区域河流生态水文联系的变化情况。 |
| 关键词: 生态水文联系 变异分区 水文改变指标 层次聚类 渭河流域 |
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| 基金项目:国家自然科学基金项目（51009009，51379014）；中央高校基本科研业务费专项（310829152018） |
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| Division of eco-hydrologic connection variability in Wei River basin |
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ZHANG Hongbo,GU Lei,CHEN Keyu,et al
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| Abstract: |
| 【Objective】The division of eco-hydrologic connection was conducted to demonstrate the spatial variability and provide theoretical basis for maintaining eco hydrologic connection in river basin.【Method】The paper extracted the indicators of hydrologic alteration (IHA) from hydrological series of 21 hydrometric stations in Wei River basin,and evaluated their alterations and spatial distribution between pre-impact and post-impact periods by range of variability approach (RVA).An index system was also established based on the original IHA for division and hierarchical cluster procedures (HCP) was used to obtain the division results about alteration degrees on eco-hydrologic connection in basin.The results were compared to that of the principal component analysis to verify the rationality of HCP division.【Result】According to variation degrees of eco-hydrologic connection in Wei River basin,3 variation regions,i.e.,the high alteration region,the moderate alteration region and the low alteration region,were divided to represent the spatial distribution of the variation degree.The 3 regions were further divided into 5 sub-regions depending on different leading indicators.In the high alteration region,the stations with highly altered indicators such as high/low flow pulses and mean flow in wet season were grouped into high alteration region Ⅰ,whereas the stations with highly altered indicators such as minima/maxima flow condition and rate of change were grouped into high alteration region Ⅱ.In the moderate alteration region,the stations with obviously altered indicators such as high/low flow pulses and rate of change were grouped into moderate alteration region Ⅰ,and the stations with strongly altered indicators such as minima flow condition,high flow pulses and mean flow in wet season were grouped into moderate alteration region Ⅱ.The low alteration region was not subdivided due to the similar altered indicators.The HCP can be used for the spatial division on eco-hydrologic connection variation with rational results.【Conclusion】The distribution of variation degree and principal variation indexes in each sub-region can be characterized.This study provides basis for river ecological protection and water engineering designing. |
| Key words: eco-hydrologic connection variation division IHA hierarchical cluster procedures Wei River basin |
