山东省近岸海域沉积物类型及变化趋势

文章依据山东省近岸海域表层沉积物调查资料,分析了沉积物粒度的时空变化特征及其影响因素。结果显示:2020年,山东省近岸海域表层沉积物粒径总体呈由近岸向远海逐渐变小的趋势,其中,粉砂含量最高,平均66.45%;砂次之,平均26.78%;黏土含量较低,平均6.77%。沉积物不同粒级组分具有明显的空间分布差异性,类型包含粉砂、砂质粉砂、粉砂质砂和砂,以粉砂为主,占调查站位的61.9%。2016—2020年,山东省近岸海域表层沉积物整体呈现粗化的趋势,其中,日照、青岛、潍坊和滨州近岸海域粗化趋势较为明显,东营次之,烟台和威海粗化程度最低。沉积物粒度时空特征的主要影响因素包含物源、区域水动力条件(如,渤海和黄海海流、山东省沿岸流等)及沿海海岸工程建设情况,具体的影响机制仍需进一步调查研究。本研究成果可以为山东省近岸海域底质类型变化分析和海岸带保护与利用提供参考。

Types and Changing Trends of Sediments in the Coastal Watersof Shandong Province

Based on the survey data of surface sediments in Shandong coastal waters, the temporal and spatial variation characteristics of sediment granularity and its influencing factors were analyzed. The results showed that in 2020, the grain size of surface sediments in Shandong coastal waters gradually decreased from shore to sea, and silt content was the highest, with an average of 66.45%, sand content was the second, with an average of 26.78%, clay content was lower, with an average of 6.77%. There were significant differences in the spatial distribution of sediment grain fractions, including silty sand, sandy silty sand, silty sand and sand, and silty sand was dominant, accounting for 61.9% of the survey site. From 2016 to 2020, an overall coarsening trend of surface sediments in Shandong coastal waters was detected. And the trend was more obvious in the coastal waters of Rizhao, Qingdao, Weifang and Binzhou, followed by Dongying, and the lowest in Yantai and Weihai. The main influencing factors of the temporal and spatial characteristics of sediment granularity include provenance, regional hydrodynamic conditions (such as the Bohai Sea Current, Yellow Sea Current, Shandong Coastal Current, etc.), and coastal engineering construction, and furthermore, the specific influencing mechanism still needs further investigation and research. The research results could provide a reference for the analysis of changes in sediment types and the protection and utilization of coastal zones in the coastal waters of Shandong Province.