环境因素影响下海湾蓄淡水库底泥盐分释放试验研究  

Test investigation for salt release from sediments in a polder reservoir under effects of environmental factors

作　　者：张效龙[1,2] 朱鸣鹤[3] 郑西来[4] 

机构地区：[1]大连海事大学环境科学与工程学院,辽宁大连116026 [2]国家海洋局第一海洋研究所,山东青岛266061 [3]宁波大学,浙江宁波315211 [4]中国海洋大学环境科学与工程学院,山东青岛266000

出　　处：《海洋通报》2010年第2期135-142,共8页Marine Science Bulletin

基　　金：国家自然科学基金资助(40572142);宁波市自然科学基金项目资助(2006A610080号和2007A61005号);宁波大学学科科研基金资助(XK200562号和XY0600062号)

摘　　要：在现场调查的基础上,利用沐官岛海湾水库库区典型底质(砂质粉砂)的原状/扰动土样和地表水(海水和淡水),采用土柱和水槽试验测定了3.5m/s风速或上覆水盐分浓度、pH和温度作用下底泥盐分向上覆水体释放的时-空变化规律,并定量计算出底泥盐分的释放通量。试验结果发现,底泥的盐分释放不同程度地受到环境因素的影响。(1)风的作用能促进底泥盐分释放。在风的作用下,上覆水中盐分浓度的分布存在明显的规律性:表层水体(水土界面之上4cm水位至水体表面)盐分浓度均匀分布,底层水体(水土界面至4cm水位水体)盐分浓度非均匀分布,且在3cm水位处盐分浓度最小。(2)上覆水中盐分的浓度抑制底泥盐分的释放。(3)pH值≤7时,底泥盐分释放几乎不受影响;pH值>7时,底泥盐分释放略有增加;(4)一定温度作用下盐分浓度在水体中非线性分布,在水-土界面至7.5cm水位处为高盐分浓度区,7.5cm水位至水体水面盐分浓度含量较低。温度的升高促进底泥盐分释放。Based on the field investigation, the typical sediments （sandy silt） undisturbed/disturbed and the land surface water （seawater and freshwater） are sampled in the Muguandao Reservoir area. The temporal-spatial variations are studied for the effects of wind and temperature on the salt release from the sediments by means of the sediment column and tank tests. And the salt fluxes from sediments are calculated. The results show that the salt release is affected in different extent by different factors. （1） The salt flux is increasing under the wind. Under the effect of wind, from the water surface to the 4cm high water level above the sediments, the distribution of salt concentration is homogeneous, while it is heterogeneous below the 4cm high water level. In addition, at the level of 3cm the salt concentration reaches its lowest point. （2） The release of salt in sediments is resisted by salt concentration of the overlying water. （3） When pH≤7, the release of salt in sediment is almost not affected by the pH value, however, when pH7, it increases a little. （4） Salinity distribution is non-linear in the water under the influence of temperature, i.e. high in the layer of 0.0～7.5 cm above the water-sediment boundary, and low in the layer from the water surface to the 7.5 cm above the boundary. The salt flux from the sediments is increasing with the temperature rising.

关 键 词：海湾水库 底泥 盐分释放 浓度 风 PH 温度 

分 类 号：P736.41[天文地球—海洋地质]