1956-2012年三江源区河流流量变化及成因  

Streamflow Variation in the Three-River Headwaters Region during 1956-2012

作　　者：蒋冲[1,2,3] 李芬[2,3] 高艳妮[2,3] 王德旺[2,3] 张林波[2,3] 郭杨[2,3] 

机构地区：[1]北京师范大学全球变化与地球系统科学研究院,北京100875 [2]中国环境科学研究院,环境基准与风险评估国家重点实验室,北京100012 [3]中国环境科学研究院,国家环境保护区域生态过程与功能评估重点实验室,北京100012

出　　处：《环境科学研究》2017年第1期30-39,共10页Research of Environmental Sciences

基　　金：中国工程院重点咨询项目(2014-XZ-31);中国环境科学研究院中央级公益性科研院所基本科研业务专项基金(2014-YKY-003)

摘　　要：为研究三江源区河流流量变化及其可能成因,在1956—2012年水文气象资料基础上,借助Mann-Kendall趋势检验、流量历时曲线等数理统计方法,分析了该区域流量的年际和年内变化,并通过双累积曲线、相关分析和贡献率分析等方法对影响流量变化的因素进行了探讨.结果表明:1近57 a来澜沧江源区和长江源区的年均流量均呈增加趋势,变率分别为0.47和2.12m^3(s·a),黄河干流流量轻微减少〔-0.60 m^3/(s·a)〕,部分支流流量有所增加;河流流量的年内分布有从双峰型向单峰型过渡的趋势.黄河源区高流量和低流量都减少,长江源区高流量和低流量均增加,而澜沧江源区高流量减小、低流量增加.2气温和降水的共同作用导致河流流量的年内分布呈双峰型或单峰型的特点,降水为主导因素,秋季降水量减少导致部分河段流量分布从双峰型向单峰型过渡.3河流流量和降水量的变化基本保持一致.黄河源区和澜沧江源区流量主要受东亚季风和西风控制,而长江源区流量主要受到青藏高原季风和东亚季风的影响.20世纪80年代以来,三江源区0℃等温层高度(16.28 m/a,P<0.001)和>0℃年积温(7.30℃/a,P<0.01)均呈显著增加趋势.在区域快速增温背景下,冰川和积雪消融给河流流量造成的短期增加效应不可持续,由此对水源涵养功能构成严重威胁.The Three-River Headwaters Region（ TRHR） in China is a critical ecological barrier as well as water regulation and conservation area. In order to investigate streamflow variation and find the possible causes,hydrological and meteorological data were collected from 1956-2012,and modified Mann-Kendall tests,flow duration curves and other statistical analyses were used to investigate the inter-annual and intra-annual change,in particular the changes of characteristic value. Meanwhile,double mass curve,correlation analysis and contribution ratio analysis were used to analyze the influencing factors of streamflow. The results showed that：（ 1） Over the past 57 years,the annual streamflows in Lancang River Basin（ LRB） and Yangtze River Basin（ YARB） increased with the slopes of0. 47 and 2. 12 m^3/（ s·a） respectively. Meanwhile,the streamflow in the mainstream of Yellow River Basin（ YRB） slightly decreased（- 0. 60 m^3/（ s·a））. However,in some tributaries,it presented an increasing trend. The intra-annual distribution of streamflow shifted gradually from double peak pattern to single peak pattern. In the source region of YRB and YARB,both high flow（ Q5） and low flow（ Q95） decreased or increased together.For the LRB,the high flow decreased,but low flow increased.（ 2） Intra-annual distribution of streamflow presented unimodal and bimodal pattern,which was jointly influenced by temperature and precipitation variation,with precipitation being the dominant factor. The reduced precipitation in autumn led to streamflow transiting from bimodal to unimodal pattern.（ 3） Annual streamflow and precipitation maintained consistent change trends. The streamflow in YRB correlated positively with the East Asian monsoon index（ R = 0. 21,P 0. 05）; meanwhile,it correlated negatively with westerly index（ R =- 0. 62,P 0. 01）. The streamflow of YARB was mainly controlled by the East Asian monsoon and Tibetan Plateau monsoon; as for LRB,it was similar to YRB,but the correlation coefficie

关 键 词：三江源区 流量 季风 冰川 积雪 归因分析 

分 类 号：X171.1[环境科学与工程—环境科学]