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通过对毛乌素沙漠南缘萨拉乌苏河流域米浪沟湾地层中有机质含量(TOC)和饱和烃分布特征,以及沉积物中碳酸盐碳氧同位素组成的分析,讨论了该地区末次间冰期以来生态环境的演变特征和过程。MIS5阶段为森林草原环境,气候比较湿润,河流径流量较大;MIS4和MIS2阶段气候干冷,以沙漠堆积为主,但MIS2在16.9-18.4kaBP期间有一次持续大约1.5ka的古环境适宜时期,森林草原发育;MIS3阶段气候温暖湿润,森林草原环境,湖泊发育;全新世早中期总体上向干旱方向发展,湖泊动荡短暂,为较少森林的草原环境。到晚全新世以沙漠沉积为主,成为与目前生态环境相似的干草原环境。该地区的生态环境演变特征反映出主要受冬夏季风变化控制,但如果西风环流加强时期植被也相对发育。
Based on the analysis of the distribution of organic matter (TOC) and saturated hydrocarbon in the Mi Langgou Bay formation and the carbon and oxygen isotopic composition of carbonates in the sediments of the Salawusu River basin in the southern margin of Mu Us Desert, the last inter-glacial period Since the evolution of ecological characteristics and process. The MIS5 stage is the forest grassland environment, the climate is humid, and the runoff of the river is relatively large. In the MIS4 and MIS2 stages, the climate is dry and cold, with desert accumulation as the main stage. However, during the period of 16.9-18.4 kaBP, MIS2 has an ancient paleo-environment period of about 1.5 ka, In the stage of MIS3, the climate is warm and humid, the forest and steppe environment and lakes are developed. In the early and middle Holocene, the lake developed generally in the direction of drought and the lake was turbulent for a short time. In the late Holocene, sediments dominated by the desert and became the steppe environment similar to the current ecological environment. The evolution of the ecological environment in this area reflects that the vegetation is mainly controlled by winter and summer monsoon changes, but vegetation also develops relatively when the westerly circulation increases.