雪宝顶流域黄龙“8·8”地震后短期内主要水环境变化特征

富含Ca2+ 和HCO3-的水体是黄龙钙华地貌得以持续沉积的首要条件。为明确2017年九寨沟“8·8”地震是否对黄龙脆弱钙华体产生影响并进而导致水环境的改变，于2017年10月和2018年8月对黄龙3个主要监测点进行了水样采集和水质参数检测。通过主成分分析震前的多次水质检测结果，得到影响黄龙水化学的主要参数，并与震后的水化学参数进行对比分析，发现:2016年（震前）水质参数显示pH、总磷、总氮对黄龙水质起主要贡献作用，地震后水体的pH、Ca2+ 和HCO3-含量上升，而总磷含量则下降较多，表明地震对黄龙钙华体内部结构产生了影响，导致上升泉（转花泉）中的Ca2+ 和HCO3- 含量增加，并影响了pH，而震后水体中的总磷含量减少，这可能与游客数量大幅度减少有关；“8·8”地震对黄龙钙华沉积区水环境造成了影响，并有利于钙华沉积。 

Characteristics of water environment changes in a short period after the "8 August 2017" earthquake in Huanglong, Xuebaoding watershed

The deposition of Huanglong travertine needs water which is rich in calcium ions and hydrogen carbonations. The purpose of this study was to determine whether the 2017 Jiuzhaigou earthquake had an impact on the fragile travertine in Huanglong and caused the change of the water environment subsequently. Water samples were collected and tested at three monitoring sites in Huanglong in October 2017 and August 2018， respectively. Based on the principal component analysis of many times of water quality tests before the earthquake，the main parameters affecting the chemistry of Huanglong water were determined，and the main parameters after the earthquake were compared and analyzed. The principal component analysis of water quality parameters in 2016 show that the pH value，total phosphorus and total nitrogen played a major role in the water quality of Huanglong. The pH，Ca2+ and HCO3- contents increased，while total phosphorus content decreased after the earthquake. The results show that the earthquake has a little influence on the structure of Huanglong travertine，leading to increase of Ca2+ and HCO3- ion content in the rising spring（Zhuanhua spring），and also affected the pH value. The decrease of TP content in the water after the earthquake may be related to the decrease in the number of tourists. The analysis suggests that the earthquake has some effect on the water environment of the sedimentary area of Huanglong travertine and was favorable to the deposition of travertine.