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荧光光谱是洞穴次生沉积物古环境、古气候重建的重要指标之一,充分理解产生洞穴次生沉积物的滴水的荧光变化对现代环境、气候的响应关系,是较好利用该指标的关键.利用三维荧光光谱分析4个岩溶洞穴系统溶解有机碳(DOC)荧光特征,结果表明洞穴系统中土壤水及洞穴滴水中的DOC荧光类型主要以类富里酸荧光和类蛋白荧光为主;类富里酸荧光强度与DOC浓度有很好的线性关系,指示了洞穴滴水DOC来自洞穴上覆土壤层.洞穴滴水类富里酸荧光在林地覆盖下的凉风洞激发发射波长变化较小,激发波长相对于其他3个洞穴滴水的稍长,而荧光强度变化较大;灌草丛覆盖的将军洞激发发射波长及荧光强度变化最大,激发波长较短,揭示洞穴系统上覆植被的变化明显地影响到滴水的荧光光谱特征.
Fluorescence spectrum is one of the important indicators of paleoenvironment and paleoclimate reconstruction of cave secondary sediments. It is the key to make full use of this index in order to fully understand the response of the change of fluorescence of drip of secondary sediment to the environment and climate . The fluorescence characteristics of dissolved organic carbon (DOC) in four karst cave systems were analyzed by three-dimensional fluorescence spectroscopy. The results showed that the DOC fluorescence types in the soil water and cave drip in the cave system were dominated by the classes of fulvic acid-like fluorescence and protein-like fluorescence. There was a good linear relationship between the acid fluorescence intensity and the DOC concentration, indicating that the DOC of cave drip was from the overlying soil layer of cave cave. The drip type fulvic acid fluorescence had a small change of excitation emission wavelength in the cold wind tunnel covered by woodland, The other three caves drip slightly longer, but the fluorescence intensity changes greatly; the shrubs covered by the General Cave excitation emission wavelength and fluorescence intensity changes the shortest, excitation wavelength is shorter, revealing changes in the vegetation cover of the cave system significantly affect the drip Fluorescence spectrum characteristics.