城市红树林湿地沉积物的矿物组成特征及影响因素

以深圳城市红树林湿地沉积物为研究对象, 分析其矿物组分和理化性质, 探究其矿物组成特征及影响因素。结果表明: 1) 深圳市红树林湿地表层沉积物的矿物组成以黏土矿物(16.5%~73.5%)和石英(22.0%~81.2%)为主, 随着深度增加, 不同样地的沉积物中钾长石、黄铁矿和石盐等矿物含量存在差异; 2) 表层沉积物中, 黏土矿物主要为伊蒙混层矿物(44%~76%)、高岭石(0%~40%)、绿泥石(0%~24%)和伊利石(2%~21%), 以伊蒙混层矿物为主; 3) 不同深度的沉积物中黏土矿物组成与表层沉积物基本上一致, 与沿海区域没有植被的珠江口和大亚湾等地的沉积物存在显著差异。相关性分析结果表明, 深圳市红树林湿地沉积物的矿物组成主要受盐度、总硫(TS)和总有机碳(TOC)影响, 其黏土矿物组成则主要受pH值、盐度、TOC和沉积物粒径影响。

Characteristics and Influencing Factors of Mineral Composition of Urban Mangrove Sediments

Taking the sediments of Shenzhen urban mangrove wetland as the research object, the mineral composition and physical and chemical properties of the sediments are analyzed, and the characteristics of mineral composition and influencing factors are explored. The main results show that the whole rock mineral composition in surface sediment is given priority to clay minerals (16.5%?73.5%) and quartz (22.0%?81.2%), and there are differences in the contents of potash feldspar, pyrite, and rock salt in different samples at different depths. The main types of clay minerals in surface sediments are imonite (44%?76%), kaolinite (0%?40%), chlorite (0%?24%), and illite (2%?21%), and are dominated by imonite. The distribution characteristics of clay minerals at different depths are basically the same as those in surface sediments. There are significant differences in the composition of clay minerals in the sediments of the Pearl River Estuary and Daya Bay without vegetation. Correlation analysis shows that the composition of whole rock minerals is mainly affected by salinity, TS and TOC, while the composition of clay minerals is mainly affected by pH, salinity, TOC, and sediment particle size.