中亚热带红土与水稻土铁锰结核理化特性与形成环境对比

The Composition and Dipositing Condition of Ferro-manganese Nodules Developed in Quaternary Red Earth and Paddy Soil in Mid-subtropica Zonie,China

通过中亚热带第四纪红土和金衢盆地现代水稻土中铁锰结核的理化特征对比发现,水稻土铁锰结核的外部特征、内部结构以及化学组成与第四纪红土中的结核既具有一定的相似性又存在着明显差别。第四纪红土中的结核与水稻土中的结核都是在干湿交替的环境中发育形成的。水稻土中结核的形成是水稻生长期的渍水、还原作用和收获后的控水、弱氧化作用交替进行的结果,形成时间短暂,环境较为稳定;第四纪红土结核的形成是气候环境周期性干湿变化的结果,结核淀积时段气候干热,氧化作用强烈,反映第四纪红土形成环境的不稳定性。

The structure and elemental geochemistry the Quaternary red earth were studied. Accumulation were discussed. of ferro-manganese nodules developed in the paddy soil and mechanisms of Fe-Mn nodules and environmental implication Firstly, the external patterns, internal structure and elemental compositions of Fe-Mn nodules in the paddy soil and the Quaternary red earth have certain similarities, but there are differences in some degree. Secondly, both the nodules in Quaternary red earth and paddy soil resulted from the alternations of the redox. Third, the physical and chemical characteristics of Fe-Mn nodules developed in paddy soil suggest a strong reduction and a poor oxidation process. Compared with the former, the nodules occurred in the Quaternary red earth were deposited in a strong oxidation. This means that the environment was hot and dry during the nodule accumulation. The climate environment was unstable.