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通过对花海古湖泊沉积剖面8.42~0.405m沉积物样品的矿物和化学元素测定,分析了沉积物中盐类矿物含量及化学元素K/Na比值的变化情况,结合已有的年代地层结果,重建了花海古湖泊10.47~5.5cal ka BP湖水盐度变化.结果表明:花海湖泊全新世湖相沉积阶段中,除个别层位以硫酸盐类矿物沉积为主外,早全新世(10.47~8.87cal ka BP)和中全新世(8.87~5.5cal ka BP)均以碳酸盐盐类矿物沉积为主,并且早全新世时期K/Na高于中全新世时期,揭示了早全新世时期湖水盐度高于中全新世时期.这一结果与该湖泊沉积过程所揭示的湖泊水位变化、粒度等揭示的有效湿度变化具有一致性,表明花海湖泊早、中全新世湖水盐度的高低可以指示其湖泊水位的变化,并间接反映了有效湿度的变化.结合花海湖泊晚全新世湖泊萎缩、气候干旱的特点,该区域早、中、晚全新世气候干湿变化变化模式可以概况为早全新世降水增强、气候呈现由干向湿的转变,中全新世有效湿度最大,晚全新世气候干旱.这种全新世气候干湿变化模式有别于西风区,亦与季风区不完全相同,呈现出了一种季风-西风过渡带全新世气候干湿变化的模式.
By analyzing the mineral and chemical elements of sediment samples from 8.42 ~ 0.405m in the sediment section of Huaihe Lake, the changes of mineral content and chemical element K / Na ratio in sediments were analyzed. Based on the results of previous age strata, The results show that in the Holocene lacustrine sedimentation stage in Huaihai Lake, except for the individual layers of sulphate deposits, the early Holocene (10.47 ~ 5.5cal ka BP) ~ 8.87 ka ka BP) and Middle Holocene (8.87-5.5 ka ka BP) are mainly carbonate mineral deposits, and the K / Na in the Early Holocene is higher than that in the middle Holocene, revealing that the Early Holocene During the period, the salinity of the lake was higher than that of the middle Holocene, which is consistent with the change of the effective humidity as revealed by the change of the lake water level and the grain size revealed by the lake sedimentation process, indicating that the early and middle Holocene lake salinity High and low can indicate the change of lake water level and indirectly reflect the change of effective humidity.Combining with the characteristics of the late Holocene lakes in Huaihai Lake and climate aridity, the patterns of climate change in early, middle and late Holocene can be summarized for In the early Holocene, the precipitation increased, the climate changed from dry to wet, the mid-Holocene had the highest effective humidity, and the late Holocene had arid climate.The pattern of climate change during the Holocene was different from the westerly and monsoon regions , Showing a monsoon - westerly transitional climate changes in the Holocene climate mode.