【摘要】 位于陆海交汇区的河口潮滩对台风作用的响应极为敏感。台风大浪极可能构成河口潮滩沉积过程的快速变化,进而不利于潮滩保护、开发及利用。基于此,本文利用200509号"麦莎"台风作用前后长江口南汇潮滩采集的沉积物样品及水文资料,探讨台风高能事件作用下河口潮滩动力沉积过程及其主控因素。结果表明长江口潮间带不同区域沉积作用对于"麦莎"台风具有不同的响应:台风前潮滩沉积物以粗粉砂和细砂为主,台风后粗粉砂减少及细砂增加,潮滩沉积物中值粒径φ值减小,沉积物粗化;高潮滩处沉积物变细,分选性变差,而中潮滩和低潮滩沉积物的变化特性为沉积物粗化,分选变好;台风所引起的风暴增水以及潮流、波浪作用的增强是引发潮滩沉积过程发生改变的主要因素。更多还原

【Abstract】 The tidal flat of the estuary located in the confluence of land and sea is extremely sensitive to the response of typhoons. Typhoons and surges are likely to constitute a rapid change in the sediment dynamics of the tidal flats in the estuary. Furthermore, it is not conducive for the protection, development, and utilization of tidal flats. Here, based on the sediments and hydrology of the Nanhui silty fine sand tidal flat in the Changjiang Estuary before and after Typhoon Matsa(TM), this work studies the impact of typhoons on the sediment dynamics of the tidal flat. The main results show that sedimentation in different areas of the Changjiang Estuary intertidal zone had different responses to TM: 1) The sediments were mainly coarse silt and fine sand before TM, which became coarser after TM. 2) The sediments at the high tidal flats became finer, and the sortability deteriorated, which is opposite to the change characteristics of the middle and low tidal flats after TM. 3) The storm surge elevation and enhancement of tidal current and wave action during TM are the main factors that cause the change in the tidal flat deposition process.更多还原