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湖泊是一定区域内的蓄水体。其水位高低能非常有效地指示湖盆内湿润条件的变化。这对内陆湖泊尤为如此。湖泊的湖滨阶地、沉积物岩性及水生孢子花粉、介形虫、硅藻等都能成为过去历史时期湖泊环境演变的证据。例如,沉积物的纹泥层反映的是一种深水且静态环境,而粗砂粒的沉积物反映的是一种近岸的浅水环境。在水生孢子花粉中,苔草(Carex)、狸藻(Ultricularia)等指示的是浅水相的环境,而孤尾藻(Myriophyllum)、眼子菜(Potamogeton)指示的是深水相的环境。这些都是恢复古湖泊水位变化的基础。
The lake is a reservoir of water within a certain area. Its water level can effectively indicate the change of wet conditions in the lake basin. This is especially true of inland lakes. Lake lakeshore terraces, sediment lithology and aquatic spores pollen, ostracods and diatoms can all be evidence of the evolution of lake environments in the past history. For example, the sediment layer of the mud reflects a deep-water and static environment, whereas the grit sediment reflects a nearshore shallow water environment. Carex, Ultricularia, and the like indicate aquatic environments in aquatic pollen, while Myriophyllum and Potamogeton indicate the environment of the deep-water phase. These are the basis for the restoration of ancient lake water level changes.