近40年塔里木河流域水沙演变及其空间分异特征

为探究塔里木河流域自然条件和人类活动改变造成的河流水沙变化,依据1980—2020年塔里木河干流阿拉尔站,源流玉龙喀什河控制水文站同古孜洛克站、叶尔羌河卡群站、阿克苏河新大河站和开都河焉耆站的实测径流和输沙资料,利用Mann-Kendall检验、Pearson相关性分析和Pettitt非参数检验等方法,分析了近40年塔里木河流域水沙演变及其空间分异特征。结果表明:在1980—2020年期间塔里木河流域同古孜洛克站、阿拉尔站、卡群站、焉耆站径流量显著增加,新大河站、同古孜洛克站、阿拉尔站径流量出现突变点,分别在1992年、1999年、2000年,突变后较突变前增长18.23%,18.10%,62.15%; 卡群站和同古孜洛克站的输沙量没有显著变化趋势,阿拉尔站、新大河站和焉耆站的输沙量都显著减少,突变点都在2001年,突变后较突变前降低36.73%,30.50%,68.31%。塔里木河水沙分布具有显著的空间差异,源流四站控制区的径流深存在南北空间上的差异,北部源于天山的阿克苏河和开都河径流深低于南部源于喀喇昆仑山的叶尔羌河和玉龙喀什河,从上游向下游输沙模数降低,径流主要受降雨和气温差距影响,而泥沙差异则是由于植被覆盖度变化。在上游三源流汇入干流的区间内,年平均消耗径流量98.21亿m³,径流深167.31 mm,淤积泥沙量4 424.15万t,淤积模数753.69 t/(km²·a)。对塔里木河四源一干径流泥沙实测数据的分析结果证明了塔里木河近期综合治理工程总体上取得了良好的生态环境效益。

Runoff and Sediment Evolution and Its Spatial Differentiation in the Tarim River Basin in Recent 40 Years

In order to explore the change of water and sediment in Tarim River Basin caused by the change of natural conditions, based on the measured runoff and sediment transport data of the main Tarim River at Alar Station, Yulong Kashi River Control Hydrological Station-Tongguziluo Station, Yarkant River Ka Qun Station, Aksu River Xindahe Station and Kaidu River Yanqi Station from 1980 to 2020, we analyzed the runoff and sediment evolution and its spatial differentiation characteristics in the Tarim River Basin in the past 40 years by the Mann-Kendall test, Pearson correlation analysis and Pettitt non-parametric test. The results are summarized as follows. During 1980—2020, the runoff of Tongguziluke station, Alaer station, Kaqun station and Yanqi station in Tarim River Basin increased significantly, while the runoff of Xindahe station, Tongguziluke station and Alaer station appeared abrupt change point in 1992, 1999 and 2000, respectively. After mutation, they increased by 18.23%, 18.10% and 62.15% compared with before mutation. The sediment transport at Kaqun station and Tongguziluoke station showed no significant change trend, but the sediment transport at Alaer station, Xindahe station and Yanqi station all decreased significantly. The mutation points were all in 2001, and the sediment transport after mutation decreased 36.73%, 30.50% and 68.31% compared with before mutation. Runoff and sediment distribution in Tarim River had obvious spatial differences, four origin rivers controlled the spacial differences in runoff depth, the runoff depths of north river Aksu River and Kaidu River which originate from Tianshan were below the runoff depths of the south river Yarkant River and Yulongkashi River which originate from the Karakoram. Sediment modulus decreased from upstream to downstream. Runoff was mainly affected by rainfall and temperature gap. Sediment variation was due to vegetation coverage. In the region where the three upstream streams merge into the main stream, the annual average runoff consumption was 9.821 billion m³, runoff depth was 167.31 mm, silt volume was 4 424.15 million tons, and silt modulus was 753.69 t/(km²·a). The analysis of runoff and sediment data of four sources and one main stream of Tarim River proves that the comprehensive control project of Tarim River has achieved good ecological and environmental benefits.