CAJ | 학술논문

在分析长江流域76个位点的水化学数据的基础上,运用吉布斯(Gibbs)图、三角图、主成分分析方法研究岩性对长江水表河水中离子化学特征的影响和流域的主要风化过程.结果表明,长江水系的主要离子化学特征受岩石风化作用的影响,其中碳酸盐和蒸发岩矿物对干流水系溶质的贡献率分别为43.6%和37.9%,而对支流水系溶质的贡献率分别为33.1%和39.1%.干流流域内主要的风化反应以白云石和方解石的溶解为主,而支流流域内C1~-/(Na~++K~+)接近1:1,体现出蒸发岩风化的显著特性.Si/K比值较低,表明长江流域内的风化反应是在表生环境中进行的,且产物是富含阳离子的次生矿物.
재분석장강류역76개위점적수화학수거적기출상,운용길포사(Gibbs)도、삼각도、주성분분석방법연구암성대장강수표하수중리자화학특정적영향화류역적주요풍화과정.결과표명,장강수계적주요리자화학특정수암석풍화작용적영향,기중탄산염화증발암광물대간류수계용질적공헌솔분별위43.6%화37.9%,이대지류수계용질적공헌솔분별위33.1%화39.1%.간류류역내주요적풍화반응이백운석화방해석적용해위주,이지류류역내C1~-/(Na~++K~+)접근1:1,체현출증발암풍화적현저특성.Si/K비치교저,표명장강류역내적풍화반응시재표생배경중진행적,차산물시부함양리자적차생광물.
Based on the data of 76 water samples of the Yangtze River (36 of them located in the main stream and 40 of them in ma jor tributaries and anabranches), the effect of lithology and main weathering process of the river water have been studied by means of statistical approaches such as Gibbs figure, Triangle plot and principal component analysis (PCA). The results show that the geochemistry of major ions in the Yangtze River are mainly controlled by rock weathering. Among them, carbonates and evaporates accountfor 43.6% and 37.9% of total ion equivalent concentration for the main stream, while the contribution for tributaries are 33.1% and39.1%, respectively. The primary weathering process in the main stream of the Yangtze River is the solution of dolomite and calcite.The ratio of C1~-/(Na~++K~+) in the main stream is close to 1:1, reflecting the significance of evaporite weathering. The lower Si/K ratioindicates that the weathering reactions took place in superficial environment and its products are cation-rich secondary minerals.