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通过对贵州荔波凉风洞(LFD)大气降水、土壤水、土壤气、洞穴滴水以及滴水对应的现代化学沉积物氧(氢)同位素组成的系统监测,发现LFD土壤水和滴水主要来源于当地大气降水;3种水(大气降水、土壤水和滴水)氧同位素值的变化幅度在年内依次减小,分别在0～-10‰,-2‰～-9‰和-6‰～-8‰之间;3种水氧同位素值之间存在大致协调同步的季节变化规律:雨季偏轻,旱季偏重;地表蒸发作用导致滴水氧同位素年算术平均值相对于大气降水值偏重约0.3‰以上.计算结果验证了LFD系统中洞穴次生化学沉积物形成过程基本达到了氧同位素平衡,利用洞穴沉积物氧同位素值恢复和重建古气温和降水量是可行的,但应注意研究区地表蒸发作用对氧同位素值的调节作用。
Through LFD atmospheric precipitation, soil water, soil gas, cave drip and drip water corresponding to modern chemical sediment oxygen (hydrogen) isotope composition monitoring system, found LFD soil water and drip water mainly from the local The variation range of oxygen isotope values of three kinds of water (atmospheric precipitation, soil water and drip water) decreased in turn from 0 to -10 ‰, -2 ‰ to -9 ‰ and -6 ‰ to -8 ‰ The seasonal variation of the three types of water and oxygen isotopes is roughly in synchronicity: the rainy season is light and the dry season is heavier; the surface evaporation results in the arithmetic average of the oxygen isotope of drip water being about 0.3 ‰ above the value of the atmospheric precipitation. The results verify that the formation of secondary cave sediments in LFD systems basically reaches the equilibrium of oxygen isotopes. It is feasible to recover and reconstruct the paleoclimate moderate precipitation by using the oxygen isotope values of cave sediments. However, The role of isotope adjustment.