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贵州织金地区织金洞的石笋ZJD-21,长12.3cm,运用210Pb定年显示该石笋顶部0.8cm在100年内连续生长.通过器测记录与该石笋顶部0.8cm的δ18 O记录对比显示,石笋中的δ18 O记录主要受降雨量影响,δ18 O值偏轻指示气候较湿润,且在10年时间尺度上,贵州织金地区主要表现冷/湿、热/干组合.石笋ZJD-21δ13 C记录能够反映洞穴地表植被的变化,植被差,δ13 C就会偏重.在过去100年来,δ18 O指示降雨量呈波动性变化,然而δ13 C却指示植被变差.从织金县和贵阳人口数量记录对比发现,大量人口增加,开垦农地,砍伐树木是导致δ13 C逐渐变重主要因素,并在1950年后形成石漠化景观.
The stalagmite ZJD-21 of Zhijin Cave in Zhijin area of Guizhou Province is 12.3cm long and shows a continuous growth of 0.8cm at the top of the stalagmite with a period of 210Pb over a period of 100 years.Comparing with the δ18O record of 0.8cm at the top of the stalagmite, Δ18O is mainly affected by rainfall, and the δ18O value is too light to indicate that the climate is humid, and the Zijin-Zijin area is mainly cold / wet and hot / dry on a 10-year time scale. Reflecting the changes in the surface vegetation of the cave, poor vegetation, δ13C will be biased in. In the past 100 years, δ18 O indicates a fluctuating change in rainfall, but δ13 C has instructed vegetation deterioration from Zhijin County and Guiyang population record contrast It was found that the large population increase, the reclamation of agricultural land and the felling of trees were the main factors causing the δ13C to gradually become heavier, and the landscape of rocky desertification was formed after 1950.