海南岛干季化学风化产物输出及其控制因素  

The Output of Chemical Weathering Materials from Hainan Island and Its Controlling Factors in the Dry Season

作　　者：张乾柱[1] 陶贞[1] 马赞文 唐文魁[1] 徐鹏[1] 高全洲[1,2] 林尤文 

机构地区：[1]中山大学地理科学与规划学院,广东省城市化与地理环境空间模拟重点实验室,广州510275 [2]广东省地质过程与矿产资源探查重点实验室,广州510275 [3]海南省水文水资源勘测局,海口570203

出　　处：《地球与环境》2015年第6期589-599,共11页Earth and Environment

基　　金：国家自然科学基金项目(41340019);广东省自然科学基金项目(2014A030311003,2015A030313070)

摘　　要：根据2014年1月实测的海南岛昌化江径流化学组成,运用物质平衡法和相关分析法估算化学径流组成的来源和控制因素,探讨流域化学风化产物HCO_3^-和溶解性硅(DSi)的输出及生态环境意义。结果表明昌化江流域水体呈中偏弱碱性,化学径流组成阴离子以HCO_3^-为主,阳离子以Ca^(2+)、Na^+为主。其中,77.30%的离子源于流域内硅酸盐岩的化学风化,1.38%的离子来源于碳酸盐岩风化,大气沉降对化学径流的贡献为5.45%,人类活动对干、支流化学径流的贡献分别为15.90%与21.04%,差异显著(P<0.01)。地貌条件、岩性及径流深度是影响流域化学径流组成的关键因素。昌化江流域干季输入南海的HCO_3^-和DSi量分别为2.12×10~8 mol、1.38×10~8 mol,是南海海洋生态系统初级生产力的主要物质来源之一,在南海生态系统物质循环预算中不可忽视。On the basis of chemical compositions of the Changhuajiang River in Hainan Island investigated in January 2014,sources and controlling factors were studied,the output processes of HCO3-and DSi were evaluated,and the eco-environmental mass balance and its correlation were also analyzed.Results show that water from the Changhuajiang River presents gentle to middle alkalinities.The compositions of chemical runoff were dominated by HCO3-in anions and Ca2＋ and Na＋ in cations.In chemical runoff,77.30% of ions originated from the silicate chemical weathering,and those from the carbonates chemical weathering accounted for 1.38%.The atmospheric precipitation contributed 5.45%.Additionally,15.90% and 21.04% of chemical runoff components stemmed from human activities in trunk stream and tributaries,respectively,with a significantly difference（P〈0.01）.The chemical compositions of the Changhuajiang River are mainly controlled by the terrain,lithology and runoff depth.The Changhuajiang River had transported about 2.12×10^8 mol of HCO3-and 1.38×10^8 mol of DSi into the South China Sea during a dry season,which constituted one of the main material sources for primary productivity in marine ecosystems and could not be ignored on matter cycle budget.

关 键 词：岩石风化 溶解性硅 海南岛 

分 类 号：P512.1[天文地球—地质学]