Located in the northwestern edge of the East Asian summer monsoon, Mu Us Sandy Land is sensitive to climate changes, which is an ideal area for studying paleoclimate changes and desert vicissitudes. Through the characteristics of the sediments grain size and magnetic susceptibility analysis of the Daliuta (DLT) section, based on data of OSL dating, we discussed the climate change process in Holocene of Mu Us Sandy Land. The results showed that:(1)The grain size composition of DLT section was mainly composed of medium (3.39%-73.84%) and coarse sand (1.46%-75.79%). In different sedimentary facies, the grain size components of aeolian sand were mainly medium (42.97%) and coarse sand (43.37%), the paleosol was dominated by silt (26.06%) and very fine sand (23.26%), the weak soil was dominated by medium (32.84%) and coarse sand (30.30%), and the lake-swamp sediment was mainly composed of fine (32.83%) and very fine sand (27.60%). In terms of grain-size parameters, the mean grain size ranged from fine to coarse in order of paleosol (2.86 φ), lake-swamp sediment (2.50 φ), weak soil (1.84 φ) and aeolian sand (1.04 φ), and the sorting coefficient also showed high value in paleosol (1.78) and low value in aeolian sand (0.60).(2)The magnetic susceptibility changed regularly in the whole section. The variation ranges of low, high frequency magnetic susceptibility (χlf,χhf) are similar, with the ranging from 2.50 to 115.66 (×10-8m3·kg-1) and 2.36 to 105.32 (×10-8m3·kg-1) respectively, and they showed the regularity of paleosol > lake-swamp sediment > weak soil > aeolian sand in different sedimentary facies. Meanwhile, the χlf was significantly positively correlated with the content of clay components and the mean grain size, and they showed consistent patterns of variation in vertical profile, which indicated similar climate changes.(3)The Holocene climate change in Mu Us Sandy Land has experienced at least 6 times distinct cold-warm fluctuations. Before 10.39×103 yr BP, the climate of Mu Us Sandy Land fluctuated frequently, and there were 3 climate alternations of "cold-dry, warm-wet"; (10.39~9.34)×103 yr BP, the climate was cold-dry and aeolian activities was strong; (9.34-8.68)×103 yr BP, winter monsoon was weaker and summer monsoon was stronger than before, and pedogenesis was strong; (8.68-8.29)×103 yr BP, the climate was cold and dry; (8.29-2.72)×103 yr BP, the climate was warm and wet, after reached the warmest at (6.55-3.80)×103 yr BP, it turned to cold and dry; (2.72-1.34)×103 yr BP, the winter monsoon became stronger and the desert expanded again; since 1.34×103 yr BP, the climate was close to modern climate. The climate change of Mu Us Sandy Land is related to the strength of East Asian winter and summer monsoons, which is the regional response to global climate changes.
[1] 隆浩,王乃昂,李育,等.毛乌素沙地北缘泊江海子剖面粒度特征及环境意义[J].中国沙漠,2007,27(2):187-193.
[2] 蒋复初,王书兵,傅建利,等.鄂尔多斯高原距今15 ka以来环境演化[J].地质力学学报,2014,20(2):165-173.
[3] Zhou W J,Wu Z K,Jull A J T,et al.Environmental and climatic change as recorded in geological sediments from the arid to semi-arid zone of China[J].Radiocarbon,2001,43(2):619-627.
[4] 高尚玉,王贵勇,哈斯,等.末次冰期以来中国季风区西北边缘沙漠演化研究[J].第四纪研究,2001,21(1):66-71.
[5] 杨帆,靳鹤龄,李孝泽,等.中晚全新世毛乌素沙地东南部气候变化过程[J].中国沙漠,2017,37(3):431-438.
[6] 靳鹤龄,李明启,苏志珠,等.萨拉乌苏河流域地层沉积时代及其反映的气候变化[J].地质学报,2007,81(3):307-315.
[7] 牛东风,李保生,王丰年,等.微量元素记录的毛乌素沙漠全新世气候波动——以萨拉乌苏流域DGS1层段为例[J].沉积学报,2015,33(4):735-743.
[8] 成都地质学院陕北队.沉积岩(物)粒度分析及其应用[M].北京:地质出版社,1978.
[9] Folk R L,Ward W C.Brazos river bar:a study in the significance of grain size parameters[J].Journal of Sedimentary Petrology,1957,27(1):3-26.
[10] Heller F,Liu T S.Magnetism of Chinese loess deposits[J].Geophysical Journal of the Royal Astronomical Society,1984,77:125-141.
[11] 刘秀铭,刘东生,Shaw J.中国黄土磁性矿物特征及其古气候意义[J].第四纪研究,1993,13(3):281-287.
[12] An Z S.The history and variability of the East Asian paleomonsoon climate[J].Quaternary Science Reviews,2000,19(1):171-187.
[13] Zhou L P,Oldfield F,Wintle A G,et al.Partly pedogenic origin of magnetic variations in Chinese loess[J].Nature,1990,346:737-739.
[14] 吴瑞金.湖泊沉积物的磁化率、频率磁化率及其古气候意义——以青海湖、岱海近代沉积为例[J].湖泊科学,1993,5(2):128-135.
[15] 孙千里,周杰,肖举乐.岱海沉积物粒度特征及其古环境意义[J].海洋地质与第四纪地质,2001,21(1):93-95.
[16] 陈发虎,朱艳,李吉均,等.民勤盆地湖泊沉积记录的全新世千百年尺度夏季风快速变化[J].科学通报,2001,46(17):1414-1419.
[17] 鹿化煜,安芷生.黄土高原黄土粒度组成的古气候意义[J].中国科学(D辑),1998,28(3):278-283.
[18] 董光荣,靳鹤龄,陈惠忠.末次间冰期以来沙漠-黄土边界带移动与气候变化[J].第四纪研究,1997,17(2):158-167.
[19] 王苏民,冯敏.内蒙古岱海湖泊环境变化与东南季风强弱的关系[J].中国科学(B辑),1991,7:759-768.
[20] Kukla G J.Loess stratigraphy in center China[J].Quaternary Science Review,1987,6:191-219.
[21] 夏敦胜,马剑英,王冠,等.环境磁学及其在西北干旱区环境研究中的问题[J].地学前缘,2006,13(3):168-179.
[22] 刘青松,邓成龙.磁化率及其环境意义[J].地球物理学报,2009,52(4):1041-1048.
[23] 朱立平,陈玲,张平中,等.环境磁学反映的藏南沉错地区1300年来冷暖变化[J].第四纪研究,2001,21(6):520-527.
[24] 胡守云,王苏民,Appel E,等.呼伦湖湖泊沉积物磁化率变化的环境磁学机制[J].中国科学(D辑),1998,28(4):334-339.
[25] 舒培仙,李保生,牛东风,等.毛乌素沙漠东南缘滴哨沟湾剖面DGS1层段粒度特征及其指示的全新世气候变化[J].地理科学,2016,36(3):448-457.
[26] 章新平,姚檀栋.祁连山敦德冰帽冰芯中气候记录的综述[J].新疆气象,1993,16(6):1-6.
[27] Bond G C,Showers W,Cheseby M,et al.A pervasive millennial-scale cycle in North Atlantic Holocene and glacial climates[J].Science,1997,278(5341):1257-1266.
[28] Li S H,Chen Y Y,Li B,et al.OSL dating of sediments from deserts in northern China[J].Quaternary Geochronology,2007,2(1):23-28.
[29] 侯光良,方修琦.中国全新世气温变化特征[J].地理科学进展,2011,30(9):1075-1080.
[30] Jia F F,Lu R J,Gao S Y,et al.Holocene aeolian activities in the southeastern Mu Us Desert,China[J].Aeolian Research,2015,19:267-274.
[31] Sun J M,Li S H,Han P,et al.Holocene environmental changes in the central Inner Mongolia,based on single-aliquot-quartz optical dating and multi-proxy study of dune sands[J].Palaeogeography Palaeoclimatology Palaeoecology,2006,233(1):51-62.
[32] Li S H,Sun J M,Li B.Holocene environmental changes in central Inner Mongolia revealed by luminescence dating of sediments from the Sala Us River valley[J].Holocene,2012,22(4):397-404.
[33] 许清海,肖举乐,中村俊夫,等.孢粉资料定量重建全新世以来岱海盆地的古气候[J].海洋地质与第四纪地质,2003,23(4):99-108.
[34] 施雅风,孔昭宸,王苏民,等.中国全新世大暖期的气候波动与重要事件[J].中国科学(B辑),1992,22(12):1300-1308.
[35] 黄昌庆,冯兆东,马玉贞,等.巴汗淖孢粉记录的全新世环境变化[J].兰州大学学报(自然科学版),2009,45(4):7-12.
[36] 周亚利,鹿化煜,张小艳,等.末次盛冰期和全新世大暖期浑善达克沙地边界的变化[J].第四纪研究,2013,33(2):228-242.
[37] 程波,陈发虎,张家武.共和盆地末次冰消期以来的植被和环境演变[J].地理学报,2010,65(11):1336-1344.
[38] 马冀,岳乐平,杨利荣,等.毛乌素沙漠东南缘全新世剖面光释光年代及古气候意义[J].第四纪研究,2011,31(1):120-129.
[39] 许清海,孔昭宸,陈旭东,等.鄂尔多斯东部4000余年来的环境与人地关系的初步探讨[J].第四纪研究,2002,22(2):105-112.
[40] 李容全.中国北方冰缘与分期[J].第四纪研究,1990,10(2):125-136.
[41] 刘冰,靳鹤龄,孙忠.近6 ka以来科尔沁沙地东部气候变化记录[J].中国沙漠,2011,31(6):1398-1405.