中文摘要：

罗布泊属于极端干旱的荒漠区,红柳沙包为这一地区高分辨率环境变化研究提供了计年手段和信息载体.根据罗布泊地区红柳沙包剖面的孢粉资料,结合 1956～2004年实测气候资料,运用相关分析、DCCA分析和WAPLS分析方法,定量恢复了罗布泊地区近200年以来的年均温、7月均温和1月平均相对湿度.研究结果表明,近200年以来罗布泊地区的气候变化经历了3个阶段： 1839～1886年气候由冷干向暖干转变,1891～1941年气候经历了冷湿-冷干-暖干的交替,1946～2004年表现为暖干向暖湿转变的趋势.孢粉浓度对人类活动信息有一定反映,19世纪末期以来,随着人类活动的加剧,孢粉浓度不断降低.

英文摘要：

The Lop Nur region is located in the Eastern Tarim Basin,which is the lowest part of the basin. It is one of the extremely arid desert areas in the world. The climatic characteristics in the Lop Nur region are very poor water resources,very low air humidity is low, and very serious sandstorm. In history, Lop Nur is the terminal of several main rivers in Tarim Basin and had gestated the famous ancient Loulan Civilization,which had been concerned by many scientists and explorers since the 19^th century. As a relatively closed desert,its environmental evolution is an epitome of the environmental evolution of Tarim Basin and its surrounding mountains. Therefore, the study on the recent environment change in the Lop Nur region is quite important for the regional environment change. Tamarix cones are a kind of biological landform. Some have clear sedimentary vein structure and can be used in dating and storing environmental information like tree rings. Tamarix cones in Southern Xinjiang are mainly distributed in the deltas of the Tarim River, the Kongque River, the Milan River, and other rivers. They are one of indicators of environmental change with high resolution in the Lop Nut region. A Tamarix cone at the west shore of lake Lop Nur was chosen to study, The Tamarix cone is 3.5m thick and has 168 clear sedimentary veins. We collected 35 samples in the interval of 5 veins for pollen analysis. The results show that pollen assemblages are characterized by herbaceous pollen whose percentage is up to 81.5%. The second common group includes arboreal pollen and shrubby pollen,whose percentage is 13.4%. The percentage of fern spores is only 0. 2%. The relationships between pollen assemblages and climatic element changes such as the mean temperature in year, the mean temperature in July, and the mean relative humidity in January were analyzed on the basis of the observed climatic data from 1956 to 2004. The climatic change sequence in the Lop Nur region during the past about 200a was reconstructed by using the cor