选择位于黑河下游地区的灌丛沙丘为研究对象,利用14C测年初步建立风沙沉积的年代序列,分析了风沙沉积物地球化学元素和粒度作为环境代用指标的气候意义,通过综合分析和区域对比,初步探讨该区域近300年来的气候环境变化。结果表明:常量元素的含量除Si O2外其他元素含量偏低。灌丛沙丘沉积至少记录了3次相对干旱期和3次相对湿润期。其中,1823年前、1905-1929年、1958-1973年期间,处于相对干旱期;而1824-1904年、1930-1957年、1974年至今,处于相对湿润期。黑河下游灌丛沙丘的气候变化对周边及全球气候变化有较好的响应,是研究近代气候变化的理想场所。
The work selected the nebkhas in the lower reaches of the Heihe River as the research object,using the14 C to establish the time series of aeolian sand deposition and to analyze the climatic significance of geochemical elements and grain size of aeolian sand deposition as a substitute for environment. Through comprehensive analysis and regional comparison,the regional climate change in the last 300 years in this area has been carried on the preliminary discussion. The results show that the content of the constant element is characterized by the change of SiO2 Al2O3 CaO Fe2O3 MgO K2O Na2O. The section in test site is located on climate and environment changes sensitive area,where aeolian sand depositions at least record 3 times relative drought period and 3 times the relative wet period. During the time,1823 years ago,1905 - 1929,1958 - 1973,the climate was in a cold dry period with the characteristics of relatively dry and cold. However,1824 - 1904,1930 - 1957,1974,appearing the humid climate fluctuations,had been in a relatively warm period. Climate change in the lower reaches of the Heihe River had a good response to the surrounding and global climate change,and is an ideal place to study the modern climate change.