基于IHA-RVA法四水流域水文情势变化评估

The evaluation of hydrological regime in Four River Basins based on IHA-RVA method

为了分析湘江、资江、沅水、澧水流域的水文情势变化情况,选取了湘潭、桃江、桃源和石门4个代表性水文站1959 2016年历史流量资料,应用Mann-Kendall法、累积距平法检验以及滑动T检验法分析湘、资、沅、澧四水的水文特征与水文突变点,并应用水文指标变动范围法(IHA-RVA)和水文改变度法综合评估了四水各站点突变前后水文指标改变程度。研究结果表明:(1) 1959-2016年四水流域的湘潭、桃江、桃源站年均流量均呈不同程度的增长趋势,石门站呈降低趋势;湘潭、桃江、桃源、石门站各水文站年均流量变化的突变年份分别为1991、1987、1989和1973年。(2)通过对水文突变前后各水系的水文情势的大小、频率、历时、发生时间和变化率5组水文指标以及变化程度分析,4个站点水文整体改变度分别为36%、22%、35%和42%,其中只有桃江站改变度为低度改变其余3站都处于中度改变。该研究成果可为四水流域水文情势影响评价以及流域水生生态安全提供技术支撑。

In order to analyze the hydrological regimes of Xiangjiang, Zijiang, Yuanshui and Lishui, the his torical flow data of 1959-2016 at Xiangtan, Taojiang, Taoyuan and Shimen hydrological station were select ed. The hydrologic characteristics and the mutation points of the four rivers were analyzed by Mann-Kend all method, cumulative anomaly test and sliding T test. Range of Variability Approach (RVA) and hydrolog ic change degree method were used to evaluate the change degree of hydrological indictors of the four riv ers. The results show that the average annual flow of Xiangtan, Taojiang and Taoyuan station during 1959 to 2016 havs shown an increasing trend and the Shimen station has shown a decreasing trend. The abrupt junction of average annual flow at Xiangtan, Taojiang, Taoyuan and Shimen station is 1991, 1987, 1989 and 1973, respectively. The overall degree of hydrological alternation belongs to moderate and low alterna tion. The alternation degree of Xiangtan, Taojiang, Taoyuan and Shimen station was 36%, 22%, 35% and 42%, respectively. The research can provide the technical support for the hydrological regime assessment of the four river basins and the security of river ecosystem.