| Karst cave813C, and caves modern monitoring research further stalagmites and other cave sediments paleoclimate indicators of great significance, the δ13C of changes in the caves and migration law to reflect the carbon migration law as well as climate changeresponse mechanism, which can provide a theoretical basis for stalagmite paleoclimate research. Cave drip monitoring not only helps to further understanding speleothems isotopic significance to refer to the mechanism of change on the natural environment, and also can provide relevant data for the ecological environment of the karst region.Selected located in the southeast edge of the Loess Plateau, Henan Luanchuan Ji Guan Cave typical climatic characteristics for the main object of study. Henan Luanchuan Ji Guan Cave, dripping modern monitoring on cave modern monitoring data are analyzed and discussed, explored sediments drip water, the soil, the relationship between rainfall and carbon isotope, carbon isotope response to modern environmental changes and cave mechanism. Provide a theoretical basis for the use of carbon isotopes to reconstruct paleoclimate proven relevant factors affecting cave δ13C.Henan Province the Luanchuan JIguan caves underground river cave, the water was more than three years (2009.12-2013.02), DIC monitoring and analysis, while the content of carbon dioxide in the cave, groundwater trace elements, modern secondary sediment carbon isotope (813C), and the roof of vegetation and soil carbon and nitrogen isotope environmental indicators continuous modern monitoring, data accumulation for the understanding of the migration of carbon isotopes in the region karst sediments Transformation Law After more than two years of work, the variation of the groundwater DICmade an initial understanding. Karst system of Ji Guandong modern process monitoring, starting from the end of2009, every two months from five sampling points (Yuzhu pool the hole the Tianhe underground river, the Jade Pool Palace pool water, the carp drip drip of water and the Temple Ice Lantern drip drip water) to obtain water samples, soil, oak leaves and other specimens made from the top of the cave. Comprehensive analysis comparing groundwater the DIC changes in the characteristics corresponding to the on-site monitoring of environmental indicators found:1.Two dripping point In Jiguan Cave as well as an underground river and two water samples δ13C value was significantly influenced by the seasonal change. In addition to the the YCG extrauterine other locations minimum October, soil δ13C trend consistent, and dripping point of the with the "TGBD" secondary sediment813C also consistent trend showing. Meanwhile, the due to dripping migration path, the residence time, the caves air and the outside air exchange, tourist activities and other factors on water δ13C, the the cave pool water δ13C changes cave changes more complicated.2.Ji Guan cave monitoring and cave drip water chemistry characteristics contrast, each drip points cation winter was significantly higher than in summer, showed the dilution effect of the precipitation of ions. At the same time, the dripping point cation obvious differentiation of differences of less than two meters away the two dripping point carp TGBD in on the value of various observations, especially Ca2, HCO3-difference obvious, might be due to the DIC in the multiplicity of control factors, resulting in time and space on the fractionation phenomenon Ji Guan Cave study has been initially show this characteristic.These studies have shown that Ji Guan Cave groundwater the DIC changes in the controlled factors outside the cave climate, vegetation and soil carbon content is closely related to. Show cave dripping migration variation of basic karst sediment migration conversion law of the carbon isotope data accumulation on the study cave sediments, stalagmites reaction the paleoenvironmental studies provided to explain the rational. In addition, Ji Guan Cave on vegetation field of artificial vegetation traditional theory can not explain. Ji Guan Cave tourist cave, whether human activities factors cave system integrated, yet failed to obtain evidence. |
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