变化环境下岷江黑水河流域径流演变特征分析

Characteristics of Runoff Variation of Heishui River Basin in the Upper Reach of Minjiang River in Changing Environment

系统分析了岷江上游右岸的一级支流黑水河径流在变化环境下的演变特征。基于黑水河沙坝水文站1960—2015年径流资料,采用改进的启发式分割算法、Mann-Kendall趋势检验法、R/S分析法和小波分析法等对径流序列的演变特征进行了探索。研究结果表明:①年径流突变点为1995年;②年径流在1960—2015年间以0.32 m^(3)/(s·a)的速率呈显著下降趋势,且在未来一段时间内仍可能呈下降趋势,年径流在1995年前呈现不显著下降趋势,趋势率为0.12 m^(3)/(s·a),在1995年后呈现不显著增加趋势,趋势率为0.80 m^(3)/(s·a);③受环境变化的影响,黑水河径流突变前均值较突变后大,突变后的年际变化较突变前大,年内分配在突变点前表现为双峰,在突变点后为单峰,突变前后径流的年内变幅呈现明显的差异,该变化在一定程度上减轻了流域的防洪压力,但不利于非汛期水资源利用;④年径流具有多时间尺度变化特征,在1960—2015年间存在6、16、28 a的主周期,在1960—1995年间存在7、16 a的主周期,在1996—2015年间存在2、5 a的主周期。

This paper systematically analyzed the variation characteristics of runoff in the Heishui River Basin,the first tributary on the right bank upstream of Minjiang River,in a changing environment.The variation characteristics of runoff series were studied by using an improved heuristic segmentation algorithm,Mann-Kendall trend test,R/S analysis and wavelet analysis with the runoff data of Shaba hydrological station from 1960 to 2015.The results show the followings:①The abrupt change of annual runoff occurred in 1995.②The annual runoff showed a significant decrease trend with a decreasing rate of 0.32 m^(3)/(s·a)in the past 56 years and may keep the decrease trend in the future.During 1960—1995,the annual runoff showed an insignificant decrease trend with a decreasing rate of 0.12 m^(3)/(s·a),and the period of 1996—2015 witnessed an insignificant increase trend with an increasing rate of 0.80 m^(3)/(s·a).③Under the influence of environmental changes,the average annual runoff before the change point was larger than that after the point,whereas the inter-annual variation was smaller before the abrupt change.The intra-annual distribution form showed a double-peak curve before 1995 and a single-peak curve after 1995.The intra-annual variation range of runoff was significantly different before and after the change point,which could reduce flood control pressure in the basin but was not conducive to the utilization of water resources in non-flood seasons.④Annual runoff had multi-time-scale variation characteristics.During 1960—2015,the annual runoff had noticeable periods of 6 years,16 years and 28 years.Periods of 7 years and 16 years were found for 1960—1995 and 2 years and 5 years for 1996—2015.