基于带约束最小二乘法的海螺沟冰川区同位素三水源径流分割

中文摘要: 为克服传统端元混合分析法(EMMA)应用于同位素径流分割中多水源划分时需要多种相互独立示踪剂的缺点，提出基于带约束的最小二乘法径流分割方法，并将其应用到青藏高原东缘海螺沟冰川区。选用同位素监测数据(δ 18O、δ 18H)，采用新方法的结果表明海螺沟冰川区研究期内径流中的水源组成：冰川融水为主要补给源(约73%)，其次为地下水(约18%)，再次为大气降水(约9%)，与EMMA方法计算结果(δ 18O和Cl -、δ 2H和Cl -)及前人研究结果具有较高吻合度；经分析，在高寒区基于稳定同位素(δ 18O、δ 18H)的带约束最小二乘法多水源径流分割，减小了EMMA中加入互补示踪剂的不确定性，其结果可作为其他研究方法的佐证。该方法为资料短缺高寒区流域提供了新思路。
Abstract:Constrained least square method(LSM) was introduced to conduct three or more components hydrograph separation with stable isotopes considering that just one tracer was needed,while more than one independent tracers were required by end member mixing approaches (EMMA).Isotope hydrograph separation of Hailuogou glacier which lays the east edge of the Qinghai Tibet Plateau was analyzed as a case study.With isotope monitoring data(δ 18O，δ 18H),the application of the constrained least square method showed that approximately 73%,18%,and 9% of the stream flow was recharged by snowmelt,groundwater and precipitation,respectively.The results were similar to EMMA and previous studies.Through analysis,the new method reduced the uncertainty of EMMA when complementary tracer was added.Hence,the results could be used as a corroboration of other research methods