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干旱区发育的红柳沙包沉积纹层不仅是一种计年形式,且蕴含丰富的气候环境信息,是研究荒漠地区近现代高分辨率气候环境变化的有效代用指标。文中依据沉积纹层计年和AMS14 C、137 Cs和210 Pb等测年方法,综合确定了塔克拉玛干沙漠南缘策勒绿洲达玛沟红柳沙包沉积纹层的年代序列,并通过孢粉组合特征分析,利用WAPLS方法重建了近400年来的古植被和古气候。研究表明,1590—1813年,孢粉以草本和灌木类型占据优势,形成以蒿属、藜科、禾本科和柽柳属为主的荒漠灌丛植被类型,气候以暖干为主;1814—1930年,孢粉以灌木类型占据绝对优势,以柽柳为主,后期草本花粉增加明显,为从荒漠灌丛到荒漠草原的过渡期,气候波动较大;1931—2010年,孢粉仍以灌木和草本类型为主,形成以柽柳属、禾本科和蒿属为主的荒漠草原,平均气温小幅度下降,降水明显增多,气候总体表现为冷湿,该阶段大量出现以大禾本为主的农作物孢粉,表明这一时期人类活动对气候环境影响逐渐增大。
The depositional layer of the Himalayan sandpack developed in arid area is not only a form of dating, but also rich in climatic and environmental information, which is an effective proxy index for studying the climate change in the desert in modern times with high resolution. Based on the sedimentary layer dating and AMS14 C, 137 Cs and 210 Pb dating methods, the chronological sequence of the sedimentary layer of the Dalanggou sedimentary layer in the Cele Oasis in the southern margin of the Taklamakan Desert was comprehensively determined. According to the characteristics of sporopollen assemblages , The use of WAPLS method to reconstruct the ancient vegetation and paleoclimate of nearly 400 years. The results show that spore powder dominated the herbaceous and shrub types from 1590 to 1813 and formed the desert shrub vegetation dominated by Artemisia, Chenopodiaceae, Poaceae and Tamarix, and the climate was dominated by warm-dry. From 1814 to 1930 In the year, the sporopollen was dominated by the shrub type, mainly tamarisk, and the herbaceous pollen increased significantly in the later stage. The climate changed greatly during the transition from the desert shrub to the desert steppe. From 1931 to 2010, The main types of herbs are desert grassland dominated by Tamarix, Gramineae and Artemisia, the average temperature is slightly decreased, the precipitation is obviously increased, the climate is generally cold and wet, and a large number of crops mainly dominated by large grasses Spore and powder, indicating that human activities during this period on the impact of climate and environment gradually increased.