摘要
本文报道了东湖沉积物的pH、Eh状况和原因,沉积物间隙水的化学特征。在东湖间隙水的地球化学过程中,CaCO_3与MgCO_3的过饱和度之比为44.6,有利于CaCO_3的沉积,CaCO_3的形成趋势大于CaMg(CO_3)_2,硫体系优势场表明硫多数以SO_4^(2-)形式存在,溶解在间隙水中的SiO_2大多数为无定形硅,硅酸盐在沉淀时可吸附金属离子,使金属离子在沉积物中富集,净化水体。
Measurements were made on the pH and Eh of the sediments, and Cl^-, SO_4^(2-), S^(2-), SiO_2, Ca, Mg, Fe, Mn, Zn, Cu, Cd, Ni, Co and Cr of interstitial water of the sediments in Lake Donghu. The pH and Eh of the sediments were related to the degree of water pollution and conditions of aquatic organisms. The average concentrations (ppm) of the chemical components were: Cl^-, 25.02; SO_4^(2-),28.33;S^(2-), 1.82; SiO_2, 17.12; Ca, 63.84; Mg, 10.39; Fe, 6.68; Mn, 1.20; Zn, 0.31; Cu, 0.15 and Cd, 0.02, respectively. Ni, Co and Cr were undetected in some samples. In the geochemical processes of interstitial water in the sediments of Lake Donghu, the over saturation ratio of CaCO_3 to MgCO_3 is 44.6, the molar ratio of calium to magnesium in 9 samples was about 3.5. The system of 'CaCO_3—MgCa(CO_3)2—MgCO_3' was controled by CaCO_3. In the sulphureous system of interstitial water of the sediments in Lake Donghu, SO_4^(2-) was in the dominant field; the soluble concentrations of some metallic sulfides were greater than the related K_(sp). The soluble SiO_2 in the interstitial water was mostly in the form of amorphous silica. Hydroxyl on the surface of silicate can absorb metal ions when the silicate is in sedimentation. In this way, metal ions can be accumlated into the sediments for the purification of water.
出处
《水生生物学报》
CAS
CSCD
北大核心
1992年第2期144-152,共9页
Acta Hydrobiologica Sinica
关键词
地球化学
沉积物
间隙水
Sediment, Interstitial water, Geochemistry
