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通过野外调查和室内分析，发现在花海剖面全新世出现了三次风成沙沉积，并对其原因进行了初步分析。初步认为风成沙的细粒组分可能主要为近源湖相，而粗粒组分则为沙漠戈壁区吹来。前两次风成沙在形成时代上可能与第一新冰期相对应，反映了沙漠的扩张状态。而且分析表明第一风沙形成期的冬季风强度和沙漠化过程似要比第二风沙期强，持续时间长。本区在全新世人类大规模活动之前就曾存在两次明显的沙漠化扩张过程，这为研究区域土地退化、荒漠化等问题提供了自然背景，特别是对西部大开发战略重点之一的生态环境保护与建设具有特殊的意义。
Through field investigation and laboratory analysis, it is found that there are three times of wind-blown sediments in the Holocene at Huaihai Section, and the reasons are analyzed. It is preliminarily believed that the fine-grained components of the aeolian sand may be mainly near-sourced lacustrine facies, whereas the coarse-grained components are blown from the desert Gobi. The first two aeolian sand formations may correspond to the first new glacial period in the formation era, reflecting the expansion of the desert. Moreover, the analysis shows that the winter monsoon intensity and desertification process during the formation of the first sandstorm seem to be stronger and longer lasting than the second sandstorm period. There are two distinct processes of desertification expansion in the area before the Holocene mankind’s large-scale activities. This provides a natural background for studying the problems of land degradation and desertification in the region. In particular, the ecological environment protection And construction has special significance.