利用网格采样法比较潮间带沉积物不同粒度区域重金属含量特征

采用网格采样法,在渤海湾潮间带泥质区、泥沙过渡区和粉沙区分别以10 m和1 m为间隔,采集了384个表层沉积物样品,对Al、Fe、Ti、Mn、Ba、Sr、Zn、Cr、Ni、Cu 10种重金属含量特征进行研究,对比了潮间带不同粒度沉积物中重金属的蓄积特征.结果表明,10种重金属在淤泥、泥沙混合、粉沙3种研究区的总含量分别为147.37、98.68和94.27 g·kg-1,粒度变化造成重金属含量的显著分异;除Ba、Sr倾向在富含长石的粗颗粒区富集外,多数重金属元素呈现细颗粒区富集倾向;Sr含量受粒度变化影响最大,而Cr、Ti含量受粒度变化影响相对较小.

Comparison of Characteristics of Heavy Metals in Different Grain Sizes of Intertidalite Sediment by Using Grid Sampling Method

384 surface sediment samples were collected from mud flat, silt flat and mud-silt flat of Bohai Bay by 1 m and 10 m interval using grid sampling method. Concentrations of Al, Fe, Ti, Mn, Ba, Sr, Zn, Cr, Ni and Cu in each sample were measured by ICP-AES. To figure out the random distribution and concentration characteristics of these heavy metals, concentration of them were compared between districts with different grain size. The results show that varieties of grain size cause the remarkable difference in the concentration of heavy metals. Total concentration of heavy metals are 147.37 g x kg(-1), 98.68 g x kg(-1) and 94.27 g x kg(-1) in mud flat, mud-silt flat and silt flat respectively. Majority of heavy metals inclines to concentrate in fine grained mud, while Ba and Sr have a tendency to concentrate in coast grained silt which contains more K2O * Al2O3 * 6SiO2. Concentration of Sr is affected significantly by the grain size, while concentration of Cr and Ti are affected a little by the grain size.