黄河口总碱度保守与非保守行为探讨

The Conservative and Non-conservative Behavior of Total Alkalinity in the Huanghe Estuary

为了阐明黄河口TAlk(总碱度)的行为特征及主要影响因素,根据2004年4月黄河口TAlk实测数据,结合其它化学要素的同步观测资料对其进行了初步探讨.研究结果表明: 黄河口水体在S<24的区域范围内TAlk呈现出非保守行为,其中 S<5时TAlk非保守表现为净TAlk的'亏损', 即水体TAlk低于理论混合TAlk,是由于水体中DIC的沉淀作用引起;在盐度为8～24之间,TAlk非保守表现为净TAlk的'增加',即水体TAlk高于理论混合TAlk,主要是由于水体中颗粒碳酸盐溶解引起;水体中的CO2参与了颗粒碳酸盐的溶解,并且很可能是影响水体中碳酸盐溶解的主要因素.

In order to discover the character and the main inlluential factors of TAlk in the Huanghe estuary, a preliminary study was made based on the TAlk measurements and other cogredient observations in April 2004. The results indicate that in the Huanghe estuary in areas whose salinity is less than 24, the TAlk appears non-conservative. When the salinity is less than 5, the non-conservative TAlk behaves as the “loss” of the net TAlk, namely, the measured TAlk is less than the theoretical mixing TAlk, which is caused by the precipitation of DIC. When the salinity is between 8 and 24, non-conservation TAlk behaves as the “increase” of the net TAlk, in other words, the TAlk in the seawater is higher than the theoretical mixing TAlk, which is considered to be the results of dissolution of particulate carbonate in seawater. Hereby, the dissolved CO2, which is supposed to be the dominating factor of carbonate dissolution, may play a role in the above dissolution process.