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根据在福建罗源湾互花米草盐沼内的沉积动力要素(水深、流速、悬沙浓度和沉降速率)的观测及表层沉积物的粒度分析结果,罗源湾互花米草盐沼表层沉积物组份以粉砂和粘土为主,为粘性沉积物;互花米草盐沼内的潮流流速很小,最大值不超过7cm/s,相应地,底部切应力也相对较小,悬沙在潮周期内多处于沉降状态,表层沉积物在涨潮初期和落潮后期多发生侵蚀。在台风显著影响下,潮流流速平均值变化很小,但水流紊动能量和底部切应力显著增大,导致表层沉积物多处于侵蚀状态,在台风登陆期间潮周期内净侵蚀通量可达到40.099kg/m~2;台风影响过后,底部切应力逐渐减小,沉积物逐渐不发生侵蚀,悬沙多发生沉降,整个潮周期内以悬沙沉降为主。
According to the observation of depositional dynamic elements (water depth, velocity, suspended sediment concentration and sedimentation rate) and surface sediment particle size analysis in Spartina alterniflora salt marsh in Luoyuan Bay of Fujian Province, the surface layer of Spartina alterniflora salt marsh Sediment components are mainly silt and clay, which are sticky sediments. The tidal velocity in Spartina alterniflora is very small, the maximum value does not exceed 7cm / s, correspondingly, the shear stress at the bottom is also relatively small. Most of the sand is in the subsidence state during the tidal period, and the surface sediments mostly eroded during the early and late ebb tide. Under the significant influence of typhoon, the mean value of tidal current velocity changed little, but the turbulence energy and bottom shear stress of water flow increased significantly, leading to the erosion of surface sediments. During the typhoon landed period, the net erosion flux reached 40.099 kg / m ~ 2. After the typhoon affected, the shear stress at the bottom gradually decreased, the sediment did not erode gradually, the suspended sediment mostly settled and the suspended sedimentation was dominated throughout the tidal cycle.