1956-2018年资江干流径流输沙演变规律与特征分析

研究资江径流泥沙演变规律与变异特征,了解资江干流径流变异与输沙量变化情况,为流域水资源可持续利用提供政策建议。根据资江流域干流主要控制站1956-2018年长时间序列径流量和输沙量数据,运用累积距平法、M-K法、集中度与集中期、小波分析法和均值差异T检验法等分析资江年径流量和输沙量的演变规律与特征。结果表明:(1)径流量不同年代时段的变化率-18.2%~25.8%,Z统计值为0.7058,径流量变化趋势不显著;而输沙量减少趋势较为明显,Z统计值为-5.0592,通过信度99%的显著性检验;(2)资江年径流量未发生明显的突变,而输沙量在1995年发生了突变;(3)资江径流存在第一主周期为26a的周期性,输沙量存在第一主周期为34a的周期性规律;(4)资江径流量变化存在1956-1966年、1982-1988年2002-2015年3个少水期,1967-1981年、1989-2001年、2016-2018年3个多水期,输沙量变化存在1956-1976年、1988-1997年2个多沙期,1977-1987年、1998-2018年2个少沙期;(5)径流量集中度为31.8%,输沙量集中度为73.7%,资江径流泥沙年内分配不均匀性特征明显。

Evolution and Characteristics of Annual Runoff and Sediment Transport in the Main Stem of Zijiang River, 1956-2018

Based on the long-term sequence runoff and sediment transport data of the main control station of the main stream of Zijiang River Basin from 1956 to 2018, the evolution law and characteristics of the annual runoff and sediment transport in Zijiang River were analyzed by using the cumulative anomaly, M-K method, concentration and centralization, wavelet analysis and mean difference T test method. The result shows: (1) Trend, the change rate of runoff in different periods is between -18.2 and 25.8%, and the Z statistic is 0.7058, indicating that the trend of runoff is not significant. The decreasing trend of sediment transport is more obvious, and the Z statistic is -5.0592. The significance test is 99%, which indicate that the reduction trend is significant. (2) Abrupt change, there was no obvious mutation in the annual runoff, and the sediment transportation changed abruptly in 1995. (3) Periodicity, There is periodic period of 26a in the water runoff, and there is periodic law of 34a in the sediment transport. (4)Phase, There are three periods of water shortage from 1956 to 1966, 1982 to 1988, 2002 to 2015, and three multi-water periods from 1967 to 1981, 1989 to 2001 and 2016 to 2018. There are two periods of sediment-laden in 1956-1976 and 1988-1997, and two periods of low sediment discharge in 1977-1987 and 1998-2018. (5) concentration and centralization, the concentration of runoff and sediment transport is 31.8% and 73.7%, respectively. The distribution of runoff and sediment is characterized by uneven distribution.