以1961~2007年三江源区的气象及径流资料为基础,采用M-K法和R/S分析法分析三江源区气候及水文要素变化趋势及进行未来变化趋势预测,并采用主成分分析法判定径流过程的主要驱动要素。研究表明:三江源区气温普遍显著升高,水面蒸发和地温随着气温的升高也不断增加,降水的增加并不显著,而年径流尤其是夏秋季节径流存在明显减小的趋势。R/S分析结果表明气候和水文要素未来总体的变化趋势与过去一致。三江源区径流过程是由气温起主导作用,径流对气温变化较降水变化更为敏感。本研究将为三江源区水资源开发利用及优化配置提供科学借鉴,同时为三江源区的生态建设和保护提供参考依据。
Based on the meteorological and runoff data of the Three-River Headwater Region during 1961~2007,the change trend of climatic and hydrological factors and the tendency predict in the future were analyzed by the Mann-Kendall technique and Rescaled range analysis.Meanwhile,principal component analysis was used to judge the main driving factor.The results showed that air temperature increased sharply and water surface evaporation and soil temperature increased with the increase of air temperature,whereas the increasing tendency of precipitation was unremarkable.The annual runoff,especially summer and autumn runoff,reduced sharply and the runoff coefficient also showed a decreasing trend.The result of Rescaled range analysis showed that the variation trend of future was identical to the past.The air temperature,soil temperature and water surface evaporation were the leading driving factors of the runoff process,and the increase of them caused the decrease of runoff.However,the increase of precipitation caused the increase of runoff.This study should be helpful for local water resources planning and management,and also should be significant for the study of the influence of global warming on ecosystem evolution,permafrost degradation and water resources safety.