摘要
为了解贵州喀斯特地区石漠化的成因及形成时期,对采自该地区织金洞的石笋样本进行同位素年代测定。210Pb及U-Th定年结果显示,该石笋生长于1 100 a内。对测得的218个δ18O和δ13C数据进行分析,结果发现:织金地区的气候在AD900～950,AD1050～1100,AD1150～1350,AD1450～1550,AD1650～1700和AD1850～1950期间,相对湿润。在AD950～1050,AD1100～1150,AD1350～1450,AD1550～1650,AD1700～1850时段,气候较干旱。小冰期的前半段,织金地区气候特征以冷/湿为主,后半段气候以冷/干为主。在南宋之前,织金地区植被未受到人类活动的影响。之后随着人类活动的增加,植被开始退化,近百年来,随着大规模移民的进入,尤其是过去50 a以来,石漠化景观基本形成。
For exploring the cause and formation stage of rocky desertification in karst area in Guizhou Province, the stalagmite sample of Zhijin area of Guizhou Province is paleomagnetically studied. The results show that the stalagmite grew in the past 1100 years. The measured data of δ^181O and δ^13C show that the climate of Zhijin was wet during AD 900 -950, AD1050 - 1100, AD1150- 1350, AD1450- 1550, AD1650- 1700 and AD1850- 1950, and was dry during AD 950- 1050, AD1100 -1150, AD1350 - 1450, AD1550 - 1650 and AD1700 - 1850. The main climate mode of Zhijin was cold/wet in the first half of Little Ice Age, and cold/dry in the second half. The vegetation was not destroyed due to human impact until Nansong Dynasty （AD 1127 - 1279）. However, the results show that during the past 100 years, the surface vegetation have been in a strongly declining state due to human impact. In the past 50 years, the surged population has caused serious karst- desertification in the area, the rocky desertification is formed.
出处
《人民长江》
北大核心
2013年第1期30-33,共4页
Yangtze River
基金
国家自然科学基金资助项目(41001367)
