Evaluating hydrologic alternation along the East River basin, southern China, under the changing environment

Abstract

采用可视化分析软件包XmdvTool来评价复杂环境下东江中上游流域(1952-2002)水文变异以克服常规RVA方法的限制,在分离了气候变化对水文变异影响后,结合RVA方法系统地研究了华南东江中上游流域由于筑坝等人类活动引起的河流水文变异时空演化规律.结果表明:(1)1952-2002间由筑坝导致的最显著的东江中上游流域水文变异是最小3d流量,低流量持续时间、1月平均流量和7月平均流量等3个IHA因子,(2)在河源和岭下两站水文变异9个IHA因子相关图中,1月和2月平均流量,1月平均流量和最小90d流量相关图中各存在一个较为明显的线性回归趋势,表明上述因子存在较明显的相关关系,(3)东江中上游综合水文变异强度南大至小分别为:河源、龙川和岭下.运用高维水文数据可视化分析技术结合RVA方法可有效用于天然河流水文变异时空变化研究.研究结果对于东江河流生态环境管理、生态恢复和水资源一体化管理具有重要意义,可为流域水文变异的理论与方法研究提供借鉴.;We use the visualization package XmdvTool to enhance the evaluation of the spatio-temporal patterns of the dam-induced hydrologic alternation dominated the middle and upper reaches of East River, south China during non-flood seasons (1952-2002). Results indicate that:1) Along the East River, dams had greatly altered the natural flow regime, range condition and the spatial variability;2) The 6 most remarkable indicators of hydrologic alternation induced by dam-construction were the rise rate, 3-day maximum, Low pulse duration, January and July of the East River during 1952-2002;3) The spatio-temporal hydrologic alternations were different among 3 stations. Under the influences of 2 large multi-purpose dams, the rank of the overall degree of hydrologic change were Lingxia, Heyuan and Longchuan station along the middle and upper reaches of East River. Visualization techniques for the high-dimensional hydrological datasets, together with RVA approach, might be useful to detect the spatio-temporal hydrologic changes. The unique way of integrating spatial, temporal and multi-element hydrological components provided visually-enhanced insights that were not possible with traditional analysis tools for water resources management.