【摘要】 根据乌兰布和沙漠北部东海子湖沉积纪录,对146cm的连续沉积进行146个样品的沉积结构分析,并运用沉积结构直方图对比、平均粒径值(Mz值)、沉积物标准离差(σ1值)、风力降尘作用指标(Kd值)等方法对沉积物代表的环境进行分析研究。依据东海子湖沉积剖面的沉积结构特征,可以将乌兰布和沙漠北部地区中全新世以来划分为4个环境变化阶段:①中全新世湖泊(河流 湖泊)沉积阶段,沉积纪录年龄为6550～2550aBP,是环境普遍温暖、湿润的阶段。②晚全新世风力作用渐强阶段,沉积纪录年龄为2550～1211aBP,是一个风力作用不断加强的环境变化时期。③晚全新世强风力作用阶段,沉积纪录年龄为1211～275aBP,也是乌兰布和沙漠风成沙堆积最旺盛的阶段。④近代强风力作用阶段,沉积纪录年龄为275aBP以来。这样的环境变化过程表明,乌兰布和沙漠的形成、演化与中国北方环境演变的总体规律是相一致的。更多还原

【Abstract】 According to the record of sediments of Donghaizi Lake, the sedimentary texture of 146 samples of the sedimentary profile are analyzed, and the expressed environment of the sediments is studied by means of sedimentary frequency curve, \%Mz\% data, \%σ1 \% data and \%Kd\% data. On the basis of the sediment feature, the processes of environmental evolution since the middle Holocene can be divided into 4 stages: ①Lake (or river\|lake) deposit stage in the middle Holocene (\{6 550\}～\{2 550\} a BP), a popularized warm and wet stage in Ulan Buh Desert. ②Wind power gradually strengthened stage in the late Holocene (\{2 550\}～\{1 211\} a BP). ③ The greatest strong wind power stage in the late Holocene (\{1 211\}～275 a BP), also the eolian sand frequently deposited period. ④ The great strong wind power stage in modern times (275 a BP～present). It is showed that the forming and revolution of Ulan Buh Desert is in the general law of environmental change in the northern China.更多还原