调水调沙工程长期实施对黄河口近岸沉积物粒度分布与黏土矿物组成特征的影响

基于对2013年10月获取的黄河口近岸海域28个沉积物样品的激光粒度分析和X-射线衍射(XRD)分析,探讨了调水调沙工程长期实施对沉积物粒度分布以及蒙皂石、伊利石、高岭石、绿泥石这4种矿物组成特征的影响.结果表明,2002年调水调沙工程实施以来,黄河口近岸海域的沉积物粒度尽管在砂含量上(平均约占23.5%)较渤海海域和黄河沉积物高,但仍主要以粉砂为主(平均约占59.1%),黏土组分相对较少(平均约占17.4%).黄河口近岸海域的黏土矿物组成与黄河沉积物的组成相近,但较调水调沙工程实施前存在较大差异,其不同组分含量整体表现为伊利石蒙皂石绿泥石高岭石.研究发现,相对渤海海域大范围的研究,对黄河口近岸海域的局部研究更能揭示调水调沙工程长期实施对河口沉积环境的影响.

Effects of Long-term Implementation of the Flow-Sediment Regulation Scheme on Grain and Clay Compositions of Inshore Sediments in the Yellow River Estuary

Based on the laser particle size and X-ray diffraction (XRD) analysis, 28 sediment samples collected from the inshore region of the Yellow River estuary in October 2013 were determined to discuss the influence of long-term implementation of the flow-sediment regulation scheme (FSRS, initiated in 2002) on the distributions of grain size and clay components (smectite, illite, kaolinite and chlorite) in sediments. Results showed that, after the FSRS was implemented for more than 10 years, although the proportion of sand in inshore sediments of the Yellow River estuary was higher (average value, 23.5%) than those in sediments of the Bohai Sea and the Yellow River, silt was predominated (average value, 59.1%) and clay components were relatively low (average value, 17.4%). The clay components in sediments of the inshore region in the Yellow River estuary were close with those in the Yellow River. The situation was greatly changed due to the implementation of FSRS since 2002, and the clay components were in the order of illite>smectite>chlorite>kaolinite. This study also indicated that, compared to large-scale investigation in Bohai Sea, the local study on the inshore region of the Yellow River estuary was more favorable for revealing the effects of long-term implementation of the FSRS on sedimentation environment of the Yellow River estuary.