Changjiang Scientific Research Institute of Changjiang Water Resources Commission, Wuhan 430010, China.
Int J Environ Res Public Health. 2019 Jul 13;16(14):2506. doi: 10.3390/ijerph16142506.
Quantifying the contributions of climate change and human activities on runoff changes is of great importance for water resource management, sustainable water resource utilization, and sustainable development of society. In this study, hydrological and climatic data from hydrological and meteorological stations in the headwaters of the Yangtze River (YRHA) from 1966 to 2013 were used to quantitatively attribute the runoff change to the impacts of climate change and human activities separately. Firstly, the change trends in precipitation, runoff depth and potential evapotranspiration were analyzed by the Mann-Kendall test method. Three methods, secondly, including ordered clustering, Mann-Kendall and cumulative anomaly curve were adopted to detect the change points of runoff at Zhimenda hydrological station and partition the whole study period into two sub-periods at the change point (base and impacted periods). Then, the elasticity coefficient method based on the Budyko hypothesis was applied to calculate elasticity coefficients of runoff to precipitation, potential evapotranspiration and land use/cover during the two periods, and to evaluate the contributions of climate change and human activities. Results indicated that during 1966-2013, runoff depth, precipitation and potential evapotranspiration all showed a significant increasing trend, with increasing rates of 7.26 mm decade, 18.725 mm decade and 7.228 mm decade, respectively. One change point (2004) was detected for the annual runoff, and 1966-2003 and 2004-2013 were respectively identified as base and impacted periods. The results of elasticity coefficients showed that the runoff depth was most sensitive to the change of precipitation during the two periods. The relative contributions of precipitation, potential evapotranspiration and parameter to runoff changes were 99.7%, -6.08% and 3.88%, respectively. Furthermore, the coupled contribution rate of other factors was less than 2.5%. Generally, results indicated that precipitation is the main factor on the historical runoff changes in this basin.
量化气候变化和人类活动对径流量变化的贡献，对于水资源管理、可持续水资源利用和社会可持续发展至关重要。本研究利用长江源区（YRHA）1966 年至 2013 年水文气象站的水文和气候数据，分别定量归因于气候变化和人类活动对径流量变化的影响。首先，采用 Mann-Kendall 检验方法分析了降水、径流量和潜在蒸散量的变化趋势。其次，采用有序聚类、Mann-Kendall 和累积异常曲线三种方法，在志萌达水文站检测到径流量的变化点，并在变化点（基准期和影响期）将整个研究期分为两个子期。然后，基于 Budyko 假设的弹性系数法，计算了两个时期内径流量对降水、潜在蒸散量和土地利用/覆被的弹性系数，并评价了气候变化和人类活动的贡献。结果表明，1966-2013 年，径流量、降水和潜在蒸散量均呈显著增加趋势，增长率分别为 7.26mm/decade、18.725mm/decade 和 7.228mm/decade。年径流量检测到一个变化点（2004 年），将 1966-2003 年和 2004-2013 年分别定义为基准期和影响期。弹性系数的结果表明，两个时期内径流量对降水变化最为敏感。降水、潜在蒸散量和参数对径流量变化的相对贡献分别为 99.7%、-6.08%和 3.88%。此外，其他因素的耦合贡献率小于 2.5%。总体而言，结果表明降水是该流域历史径流量变化的主要因素。
