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现代黄河三角洲沉积作用活跃,沉积过程复杂,沉积物颗粒特性及渗透系数空间分布特征控制着三角洲地表水与地下水之间的相互作用、区域地下水的水分和盐分运移以及湿地生态环境的动态演化过程.基于黄河三角洲陆面70个采样点10、30、90 cm深处的浅表层沉积物土样,对颗粒粒度参数和相应的渗透系数及其空间分布规律进行了计算与分析.结果表明:研究区浅表层沉积物主要由细砂与粉砂组成,有效粒径均值为5.2 μm,从三角洲顶点向海岸线大致呈条带状分布;在三角洲北部刁口河与神仙沟故道附近的河滩高地,浅表层沉积物颗粒粒径较大;沉积物渗透系数均值为0.65 m/d,空间差异较不明显;随着深度增大,渗透系数缓慢减小,且空间差异性有所增大;神仙沟故道沿线沉积物渗透系数均值为0.98 m/d,明显大于其他区域,尤其在30 cm深处沉积物渗透系数均值与方差均为全区最大;清水沟流路沿线的渗透系数均值小于刁口河沿线的,两处保护区内的渗透系数均值与空间差异性均较小;不同沉积环境下沉积物颗粒级配的差异是造成渗透系数空间差异的主要原因.“,”The sedimentprocess of modern Yellow River delta is active and complex,and the attribute of sediment particle as well as the spa-tial distribution of hydraulic conductivity dominate the surface water and groundwater interaction,water and salt transport of regional groundw-ater and the evolution of wetland ecological environment. Based on the 70 shallow sediment samples with 10 cm, 30 cm and 90 cm depth across the delta,the particle size parameters and hydraulic conductivity and their spatial distribution were analyzed. The results show that the shallow sediment is mainly composed of fine sand and silt,with an average effective particle diameter of 5.2 μm and a belt pattern from the vertex of delta to seashore;particle size of shallow sediment is large in the highland near Diaokouhe and Shenxiangou channels. The average hydraulic conductivity(K)is 0.65 m/d, with a limited spatial variation and gradually decreasing trend with depth. The average K near Shenxiangou channel is 0.98 m/d,which is notably higher than that of the other region and is the largest in average and variance for 30 cm depth. K along the Qingshuigou channel is smaller than that along the Diaokouhe channel, and the average and variance of K are both the smallest in the two reserves. The sediment particle size and distribution under different sedimentary environment are the main causes of differ-ences in K.