Magnetic susceptibility of aeolian sediments deposited since Holocene in the East of Qinghai Lake and its environmental implications
-
摘要:
在亚洲季风控制区，黄土-古土壤序列中的磁化率能够很好地反映土壤成壤强度和区域沉积环境变化，但在风成砂-古土壤序列中磁化率的古气候意义仍有待研究。选取青海湖湖东沙地典型风成砂-古土壤序列，基于AMS14C和光释光测年结果，结合土壤学中传统的土壤发育指标，对沉积物的磁化率特征及环境意义进行分析。研究表明在青海湖盆地风成砂-古土壤序列里，磁化率与成壤强度密切相关：(1)剖面磁化率总体表现为古土壤层最高、弱发育古土壤层次之和风成砂层最低的规律。相较低频磁化率χlf，频率磁化率χfd%能够更好、更细致地反映沉积环境的变化；(2)剖面中磁化率与成壤强度有关(正相关)，因成壤作用对两剖面原始物源各粒级组分的改造程度不同，磁化率与黏粒和粉砂正相关；(3)基于剖面磁化率以及粒度特征的综合分析，将青海湖湖东沙地全新世以来气候环境划分为3个阶段：10kaBP以前气候冷干，成壤作用微弱；10~4kaBP气候暖湿，成壤作用显著；4kaBP至今，气候逐渐趋于冷干，成壤作用渐弱。
Abstract:Magnetic susceptibility is an efficient indicator to the intensity of pedogenesis and depositional environment for a loess-palaeosol sequence under the Asian monsoon. However, its paleoclimatic implications still need to be revealed for an aeolian-sand-palaeosol sequence. Within the time framework established by AMS 14C and OSL dating, we studied the magnetic susceptibility characteristics of the aeolian deposits to the east of the Qinghai Lake. Taking the traditional pedogenetic indicators used in soil sciences as references, we found that the magnetic susceptibility is closely related to the intensity of soil development in the sandy land to the East of Qinghai Lake. The results show that: (1) The highest magnetic susceptibility occurs in the palaeosol layer, followed by the weakly developed palaeosol and the aeolian sand. Compared to χlf, χfd% is more efficient to reflect environmental changes; (2) The variation in magnetic susceptibility exhibits a positive correlation with pedogenesis, and is positively correlated with the content of clay and silt; (3) On the basis of comprehensive analysis, the climatic change in Qinghai Lake since Holocene could be divided into three main phases as follows: Before 10kaBP, the climate was cold and dry and the weathering process weaker. In the period of 10~8.5 kaBP, the climate turned to warm and wet. Optimum period took place from 8.5 kaBP to 4 kaBP, while the climate was warm and humid and the aeolian activity was weakened and pedogenesis became stronger. The climate was colder and drier between 4 to 1.3 kaBP. There possibly existed an abrupt climate cooling event during 3.1~2.4 kaBP. Since1.3 kaBP, the climate became colder and drier further and similar to the modern climate.
-
Key words:
- magnetic susceptibility /
- environmental change /
- pedogenesis /
- Holocene /
- Qinghai Lake
-
-
表 1 CGE、QHH和HLD剖面AMS14C测年结果及校正年代
Table 1. AMS14C dating results from the CGE, QHH and HLD profiles
样品编号 实验室编号 深度/cm 13C/12C比值 14C年龄/aBP 校正年龄/cal.aBP CGE-C-00a Beta-422379 234~236 -21.9 1970±30 1990~1870(1930±60) CGE-C-01a Beta-422380 280~282 -24.1 3690±30 4145~3930(4038±107) CGE-C-05a Beta-422381 360~362 -23.2 7210±30 8040~7965(8002±37) QHH-C-01 Beta-422375 85~87 -20.8 2080±30 2130~1950(2040±90) QHH-C-02 Beta-422376 120~122 -22.5 3030±30 3340~3160(3250±90) QHH-C-06 Beta-422377 180~182 -23.8 4230±30 4850~4710(4780±70) QHH-C-13 Beta-422378 270~272 -23.2 7910±30 8970~8605(8788±182) HLD-C-01 CG-7223 45~55 -25 4140±75 4444~4843(4643±199) 
下载: 导出CSV
表 2 HLD剖面OSL测年结果
Table 2. OSL dating results from HLD profile
样品编号 深度/cm U/×10-6 Th/×10-6 K/% 等效剂量/Gy 年剂量/(Gy/ka) 含水量/% 年龄/ka HLD-01 85~90 1.53±0.07 5.70±0.2 1.34±0.05 19.31±1.50 2.28±0.06 1.7 8.5±0.7
下载: 导出CSV
表 3 频率磁化率χfd%与其他指标的相关性检验
Table 3. Correlation between χfd% and other indexes
指标 ＜2μm 2~63μm >63μm c/f2μm χlf/(10-8m3·kg-1) CGE 0.548** 0.201** -0.235** -0.386** 0.358** QHH 0.750** 0.851** -0.85** -0.706** 0.554** 注：**p＜0.01
下载: 导出CSV
-
[1] Heller F, Liu T S. Magnetostratigraphical dating of loess deposits in China[J]. Nature, 1982, 300(5891): 431-433. doi: 10.1038/300431a0
[2] 刘东生.黄土与环境[M].北京:科学出版社, 1985: 10.
LIU Tungsheng. Loess and Environment[M]. Beijing: Science Press, 1985: 10.
[3] 刘秀铭, 刘东生, Heller F, 等.黄土频率磁化率与古气候冷暖变换[J].第四纪研究, 1990, 10(1): 42-50. doi: 10.3321/j.issn:1001-7410.1990.01.005
LIU Xiuming, LIU Tungsheng, Heller F, et al. Frequency-dependent susceptibility of loess and Quaternary paleoclimate[J]. Quaternary Sciences, 1990, 10(1): 42-50. doi: 10.3321/j.issn:1001-7410.1990.01.005
[4] Maher B A, Thompson R. Paleoclimatic significance of the mineral magnetic record of the Chinese loess and paleosols[J]. Quaternary Research, 1992, 37(2): 155-170. doi: 10.1016/0033-5894(92)90079-X
[5] 王心源, 吴立, 张广胜, 等.安徽巢湖全新世湖泊沉积物磁化率与粒度组合的变化特征及其环境意义[J].地理科学, 2008, 28(4): 548-553. doi: 10.3969/j.issn.1000-0690.2008.04.016
WANG Xinyuan, WU Li, ZHANG Guangsheng, et al. Characteristics and environmental significance of magnetic susceptibility and grain size of lake sediments since Holocene in Chaohu lake, Anhui province[J]. Scientia Geographica Sinica, 2008, 28(4): 548-553. doi: 10.3969/j.issn.1000-0690.2008.04.016
[6] 杨建强, 崔之久, 易朝露, 等.云南点苍山冰川湖泊沉积物磁化率的影响因素及其环境意义[J].第四纪研究, 2004, 24(5): 591-597. doi: 10.3321/j.issn:1001-7410.2004.05.017
YANG Jianqiang, CUI Zhijiu, YI Chaolu, et al. The influencing factors and environmental significance of magnetic susceptibility in the glacio-lacustrinal sediments on the Diancang mountains, Yunnan province[J]. Quaternary Sciences, 2004, 24(5): 591-597. doi: 10.3321/j.issn:1001-7410.2004.05.017
[7] 鲍锟山, 贾琳, 王国平.长白山区泥炭沼泽磁化率特征及其环境意义[J].湿地科学, 2009, 7(4): 321-326. http://d.old.wanfangdata.com.cn/Periodical/shidkx200904005
BAO Kunshan, JIA Lin, WANG Guoping. Characteristic and environmental significance of magnetic susceptibility of peat bog sediments in Changbai mountains[J]. Wetland Science, 2009, 7(4): 321-326. http://d.old.wanfangdata.com.cn/Periodical/shidkx200904005
[8] Feng Z D. Gobi dynamics in the Northern Mongolian Plateau during the past 20, 000yr: preliminary results[J]. Quaternary International, 2001, 76-77: 77-83. doi: 10.1016/S1040-6182(00)00091-4
[9] 凌智永, 李志忠, 武胜利, 等.新疆伊犁晚全新世风成沙—古土壤序列磁化率特征及气候变化[J].沉积学报, 2012, 30(5): 928-936. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=cjxb201205016
LIN Zhiyong, LI Zhizhong, WU Shengli, et al. Late Holocene climate change revealed by the magnetic susceptibility of paleoaeolian sand-paleosol sedimentary sequence in Yili valley of Xinjiang[J]. Acta Sedimentologica Sinica, 2012, 30(5): 928-936. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=cjxb201205016
[10] 王建, 刘泽纯, 姜文英, 等.磁化率与粒度、矿物的关系及其古环境意义[J].地理学报, 1996, 51(2): 155-163. doi: 10.3321/j.issn:0375-5444.1996.02.009
WANG Jian, LIU Zechun, JIANG Wenying, et al. A relationship between susceptibility and grain-size and minerals, and their paleo-environmental implications[J]. Acta Geographica Sinica, 1996, 51(2): 155-163. doi: 10.3321/j.issn:0375-5444.1996.02.009
[11] 吉云平, 夏正楷.不同类型沉积物磁化率的比较研究和初步解释[J].地球学报, 2007, 28(6): 541-549. doi: 10.3321/j.issn:1006-3021.2007.06.005
JI Yunping, XIA Zhengkai. Comparison and primarily interpretation of magnetic susceptibilities in different sediments[J]. Acta Geoscientica Sinica, 2007, 28(6): 541-549. doi: 10.3321/j.issn:1006-3021.2007.06.005
[12] 刘秀铭, 刘东生, 夏敦胜, 等.中国与西伯利亚黄土磁化率古气候记录-氧化和还原条件下的两种成土模式分析[J].中国科学:地球科学, 2007, 37(10): 1382-1391. http://d.old.wanfangdata.com.cn/Periodical/zgkx-cd200710010
LIU Xiuming, LIU Tungsheng, XIA Dunsheng, et al. Two pedogenic models for paleoclimatic records of magnetic susceptibility from Chinese and Siberian Loess[J]. Science China: Earth Sciences, 2008, 51(2): 284-293. http://d.old.wanfangdata.com.cn/Periodical/zgkx-cd200710010
[13] An Z S, Colman S M, Zhou W J, et al. Interplay between the Westerlies and Asian monsoon recorded in Lake Qinghai sediments since 32 ka[J]. Scientific Reports, 2012, 2: 619. doi: 10.1038/srep00619
[14] 徐叔鹰, 徐德馥.青海湖东岸的风沙堆积[J].中国沙漠, 1983, 3(3): 11-17. http://www.cnki.com.cn/Article/CJFD1983-ZGSS198303002.htm
XU Shuying, XU Defu. A primary observation of Aeolian sand deposits on eastern shore of the Qinghai Lake[J]. Journal of Desert Research, 1983, 3(3): 11-17. http://www.cnki.com.cn/Article/CJFD1983-ZGSS198303002.htm
[15] 申红艳, 余锦华.环青海湖地区风的气候变化特征分析[J].青海环境, 2007, 17(4): 170-172. doi: 10.3969/j.issn.1007-2454.2007.04.005
SHEN Hongyan, YU Jinhua. Analysis on the climate change features of the wind around Qinghai Lake[J]. Qinghai Environment, 2007, 17(4): 170-172. doi: 10.3969/j.issn.1007-2454.2007.04.005
[16] 赵以莲, 周国英, 陈桂琛.青海湖区东部沙地植被及其特征研究[J].中国沙漠, 2007, 27(5): 820-825. http://d.old.wanfangdata.com.cn/Periodical/zgsm200705019
ZHAO Yilian, ZHOU Guoying, CHEN Guichen. Sandy vegetation and its characteristics in east of Qinghai lake area[J]. Journal of Desert Research, 2007, 27(5): 820-825. http://d.old.wanfangdata.com.cn/Periodical/zgsm200705019
[17] 施雅风, 陈梦熊, 李维质, 等.青海湖及其附近地区自然地理(着重地貌)的初步考察[J].地理学报, 1958, 24(1): 33-48. http://www.cnki.com.cn/Article/CJFDTotal-DLXB195801003.htm
SHI Yafeng, CHEN Mengxiong, LI Weizhi, et al. Proliminary survey on physical geography (especially geomorphology) in the Qinghai Lake region and adjacent areas[J]. Acta Geographica Sinica, 1958, 24(1): 33-48. http://www.cnki.com.cn/Article/CJFDTotal-DLXB195801003.htm
[18] Lu R J, Jia F F, Gao S Y, et al. Holocene aeolian activity and climatic change in Qinghai lake basin, northeastern Qinghai-Tibetan plateau[J]. Palaeogeography, Palaeoclimatology, Palaeoecology, 2015, 430: 1-10. doi: 10.1016/j.palaeo.2015.03.044
[19] Liu X J, Lai Z P, Yu L P, et al. Luminescence chronology of aeolian deposits from the Qinghai Lake area in the Northeastern Qinghai-Tibetan Plateau and its palaeoenvironmental implications[J]. Quaternary Geochronology, 2012, 10: 37-43. doi: 10.1016/j.quageo.2012.01.016
[20] Lu H Y, Zhao C F, Mason J, et al. Holocene climatic changes revealed by aeolian deposits from the Qinghai Lake area (northeastern Qinghai-Tibetan Plateau) and possible forcing mechanisms[J]. Holocene, 2010, 21(2): 297-304.
[21] Reimer P J, Bard E, Bayliss A, et al. IntCal13 and marine13 radiocarbon age calibration curves 0-50, 000 years cal BP[J]. Radiocarbon, 2013, 55(4): 1869-1887. doi: 10.2458/azu_js_rc.55.16947
[22] Thompson R, Oldfield F. Environmental magnetism[M]. London: Allen and Unwin, 1986.
[23] 吉云平.不同类型沉积物中磁化率的解释[D].北京大学硕士学位论文, 2007.
JI Yunping. Interpretation of magnetic susceptibility in different sediments[D]. Master's Thesis of Peking University, 2007.
[24] 丁仲礼, 孙继敏, 刘东生.联系沙漠-黄土演变过程中耦合关系的沉积学指标[J].中国科学(D辑), 1999, 29(1): 82-87. http://d.old.wanfangdata.com.cn/Periodical/zgkx-cd199901013
DING Zhongli, SUN Jimin, LIU Tungsheng. A sedimentological proxy indicator linking changes in loess and deserts in the Quaternary[J]. Science in China (Series D), 1999, 42(2): 146-152. http://d.old.wanfangdata.com.cn/Periodical/zgkx-cd199901013
[25] 鄂崇毅, 曹广超, 侯光良, 等.青海湖江西沟黄土记录的环境演变[J].海洋地质与第四纪地质, 2013, 33(4): 193-200. http://hydz.chinajournal.net.cn/WKD/WebPublication/paperDigest.aspx?paperID=b0f17af6-6db9-46f1-a4d7-aaa0cfba8650
E Chongyi, CAO Guangchao, HOU Guangliang, et al. The environmental change recorded in Jiangxigou loess sections in Qinghai lake region[J]. Marine Geology & Quaternary Geology, 2013, 33(4): 193-200. http://hydz.chinajournal.net.cn/WKD/WebPublication/paperDigest.aspx?paperID=b0f17af6-6db9-46f1-a4d7-aaa0cfba8650
[26] 何毓蓉, 张丹.土壤微形态研究理论与实践[M].北京:地质出版社, 2015: 3-4.
HE Yurong, ZHANG Dan. Theory and Practice of Soil Micromorphology[M]. Beijing: Geological Publishing House, 2015: 3-4.
[27] 张岩青, 庞奖励, 黄春长, 等.宁夏长城塬全新世黄土-古土壤序列微形态特征及意义[J].中国沙漠, 2010, 30(6): 1491-1496. http://d.old.wanfangdata.com.cn/Periodical/zgsm201006036
ZHANG Yanqing, PANG Jiangli, HUANG Chunchang, et al. Significance of micro-morphological features of the Holocene loess-paleosol profile in loess plateau[J]. Journal of Desert Research, 2010, 30(6): 1491-1496. http://d.old.wanfangdata.com.cn/Periodical/zgsm201006036
[28] 刘进峰, 乔彦松, 郭正堂.风尘堆积全岩和石英粒度变化对风化成壤强度的指示[J].第四纪研究, 2007, 27(2): 270-276. doi: 10.3321/j.issn:1001-7410.2007.02.012
LIU Jinfeng, QIAO Yansong, GUO Zhengtang. The differences of grain size of quartz and bulk samples as an indicator of weathering intensity in the Aeolian deposits[J]. Quaternary Sciences, 2007, 27(2): 270-276. doi: 10.3321/j.issn:1001-7410.2007.02.012
[29] Berger A, Loutre M F. Insolation values for the climate of the last 10 million years[J]. Quaternary Science Reviews, 1991, 10(4): 297-317. doi: 10.1016/0277-3791(91)90033-Q
[30] Ji J F, Shen J, Balsam W, et al. Asian monsoon oscillations in the northeastern Qinghai-Tibet Plateau since the late glacial as interpreted from visible reflectance of Qinghai Lake sediments[J]. Earth and Planetary Science Letters, 2005, 233(1-2): 61-70. doi: 10.1016/j.epsl.2005.02.025
[31] An Z S, Kukla J C, Porter S C, et al. Magnetic susceptibility evidence of monsoon variation on the loess plateau of central China during the last 130000 years[J]. Quaternary Research, 1991, 36(1): 29-36. doi: 10.1016/0033-5894(91)90015-W
[32] 苏志珠, 杨宗园, 李晋昌.距今220 ka以来大同盆地沉积物磁化率反映的气候变化[J].冰川冻土, 2015, 37(2): 401-407. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=bcdt201502014
SU Zhizhu, YANG Zongyuan, LI Jinchang. Climate change reflected by the magnetic susceptibility within the deposit sediment in Datong basin, north China, since 220 ka BP[J]. Journal of Glaciology and Geocryology, 2015, 37(2): 401-407. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=bcdt201502014
[33] Chen F H, Wu D, Chen J H, et al. Holocene moisture and East Asian summer monsoon evolution in the northeastern Tibetan Plateau recorded by Lake Qinghai and its environs: A review of conflicting proxies[J]. Quaternary Science Reviews, 2016, 154: 111-129. doi: 10.1016/j.quascirev.2016.10.021
[34] LIU X Q, SHEN J, WANG S M, et al. Southwest monsoon changes indicated by oxygen isotope of ostracode shells from sediments in Qinghai Lake since the late Glacial[J]. Chinese Science Bulletin, 2007, 52(44): 539-544. http://d.old.wanfangdata.com.cn/NSTLQK/10.1039-c1em10602c/
[35] 刘兴起, 沈吉, 王苏民, 等.青海湖16 ka以来的花粉记录及其古气候古环境演化[J].科学通报, 2002, 47(17): 1351-1355. http://d.old.wanfangdata.com.cn/Periodical/kxtb200217016
LIU Xingqi, SHEN Ji, WANG Suming, et al. A 16000-year pollen record of Qinghai Lake and its paleoclimate and paleoenvironment[J]. Chinese Science Bulletin, 2002, 47(22): 1931-1936. http://d.old.wanfangdata.com.cn/Periodical/kxtb200217016
[36] 胡梦珺, 李森, 高尚玉, 等.风成沉积物粒度特征及其反映的青海湖周边近32 ka以来土地沙漠化演变过程[J].中国沙漠, 2012, 32(5): 1240-1247. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=zgsm201205009
HU Mengjun, LI Sen, GAO Shangyu, et al. Evolution process of land desertification around Qinghai lake since 32 kaBP reflected by sediment grain-size features[J]. Journal of Desert Research, 2012, 32(5): 1240-1247. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=zgsm201205009
[37] 王建国, 马海州, 谭红兵, 等.青海湖南岸黑马河黄土剖面碳酸盐含量与记录的古气候变化[J].盐湖研究, 2005, 13(4): 5-8. doi: 10.3969/j.issn.1008-858X.2005.04.002
WANG Jianguo, MA Haizhou, TAN Hongbing, et al. Change of carbonate content and record on palaeoclimate fluctuations in Heimahe loess section on southern Qinghai lake shore[J]. Journal of Salt Lake Research, 2005, 13(4): 5-8. doi: 10.3969/j.issn.1008-858X.2005.04.002
[38] 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. doi: 10.3321/j.issn:1001-7410.2001.01.008
GAO Shangyu, WANG Guiyong, HA Si, et al. A case study on desert evolution in the northwestern fringe of monsoon area, China since the Last Glacial epoch[J]. Quaternary Sciences, 2001, 21(1): 66-71. doi: 10.3321/j.issn:1001-7410.2001.01.008
[39] Feng Z D, An C B, Wang H B. Holocene climatic and environmental changes in the arid and semi-arid areas of China: a review[J]. Holocene, 2006, 16(1), 119-130. doi: 10.1191/0959683606hl912xx
[40] 杨龙, 孙永娟, 鄂崇毅, 等.江西沟1号风成剖面地球化学元素特征及古环境意义[J].盐湖研究, 2016, 24(2): 44-53. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=yhyj201602007
YANG Long, SUN Yongjuan, E Chongyi, et al. Geochemical element characteristics and paleoenvironmental significance of aeolian sediments in JXG1 section[J]. Journal of Salt Lake Research, 2016, 24(2): 44-53. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=yhyj201602007
[41] 刘思丝, 黄小忠, 强明瑞, 等.孢粉记录的青藏高原东北部更尕海地区中晚全新世植被和气候变化[J].第四纪研究, 2016, 36(2): 247-256. http://d.old.wanfangdata.com.cn/Periodical/dsjyj201602001
LIU Sisi, HUANG Xiaozhong, QIANG Mingrui, et al. Vegetation and climate change during the Mid-Late Holocene reflected by the pollen record from Lake Genggahai, northeastern Tibetan plateau[J]. Quaternary Sciences, 2016, 36(2): 247-256. http://d.old.wanfangdata.com.cn/Periodical/dsjyj201602001
-
图(4)
表(3)
计量
- 文章访问数: 2406
- PDF下载数: 34
- 施引文献: 0