海洋粘土矿物与颗石藻Emiliania huxleyi共培养的实验研究

An experimental study of co-culturing marine clay minerals and Emiliania huxleyi

颗石藻是海洋中广泛分布的超微型浮游藻,经生物矿化作用形成的碳酸钙质颗石,在古海洋学研究中具有重要意义。海洋粘土矿物与有机质的有机-无机相互作用在全球碳循环中扮演着重要角色。本文选取广泛分布于海洋的赫氏颗石藻Emiliania huxleyi与海洋粘土矿物中具有代表性的伊利石和蒙脱石共培养。通过对颗石藻生长曲线和Sr/Ca、Mg/Ca元素比值、颗石藻与粘土矿物样品的紫外可见光吸收光谱、红外吸收光谱和矿物物相等分析,研究海洋粘土矿物与颗石藻的相互作用规律。通过研究表明伊利石对颗石藻的影响较小,蒙脱石因对营养元素的吸附和颗石藻的絮凝作用对颗石藻的生长和Sr/Ca、Mg/Ca元素比值影响较大。颗石藻代谢分泌的生物分子未能通过层间插层作用进入伊利石层间,颗石藻分泌的生物分子可通过插层作用进入并储存于蒙脱石层间,海洋粘土矿物中的蒙脱石与海洋微生物的相互作用值得地球微生物家关注,可能有助于对古海洋环境的认识。

The coccolithophore widely distributed in marine environment is one of the most important algae.Coccolith, formed through biomineralization processes, has important significance in paleoceanographic study. Interactions between marine clay minerals and organic matters play an important role in the global carbon cycle. Representative coccolithophore Emiliania huxleyi and marine clay minerals of illite and montmorillonite were selected for experimental co-culturing study. Growth curves, elemental ratios of Sr/Ca and Mg/Ca, UV-Vis spectra, FTIR spectra and XRD were utilized for analysis. The results show that illite has an insignificant effect on E. huxleyi,whereas montmorillonite has significant influence on E. huxleyi in growth curves as well as element ratios of Mg/Ca and Sr/Ca due to its adsorption and flocculation effect on nutrients. Metabolic biomolecules fail to enter the interlayer of illite. However, biomolecules secreted by the E. huxleyi enter and are stored in the interlayers of montmorillonite. The presented study indicates that the interaction between marine clay mineral of montmorillonite and marine microorganisms has important geological significance, and hence geo-biologists should pay more attention to the study of the ancient marine environment.