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通过对洛川剖面 ２５０ ｋａＢＰ来蜗牛化石记录的分析，划分出 １１个化石组合带，研究了最近两个冰期旋回以来的生物组合特征，探讨了不同生态环境类型的变化规律及其主要的控制因素．结果表明：陆生蜗牛的生态演替过程，与地轴倾角和岁差变化的关系是明确的，喜温湿类蜗牛繁盛期对应着地轴倾角的增大期，喜冷干类蜗牛繁盛期对应了地轴倾角的减小期．反映了东亚夏季风在控制陆地生态演变过程中具有明显的 ４０ ｋａ变化周期，岁差的 ２０ ｋａ周期同时起到重要的调节作用， １００ ｋａ左右的周期变化在生态群落的演替过程中，并不是主要的控制因素，但它可能是陆地生态变化幅度的背景因素．
Based on the analysis of the snail fossil record of 250 kaBP in Luochuan section, 11 fossil assemblages were identified, and the characteristics of biological assemblage since the two glacial cycles were studied. The variation rules of different types of ecological environment and the main controlling factors . The results showed that the relationship between the ecological succession process of terrestrial snails and the inclination of axis and precession was clear. The heliosphere angle increased during the prosperous period, The decrease of dip angle. It shows that the East Asian summer monsoon has a significant period of 40 ka in controlling the evolution of terrestrial ecology. The 20 ka cycle of precession plays an important regulatory role at the same time. In the process of ecological community succession, the periodic change of about 100 ka is not The main controlling factor, but it may be the background factor of terrestrial ecological changes.