川西高原甘孜黄土- 古土壤容重的特征及其古环境意义 | |
Alternative Title | Characteristics and paleoclimatic significance of the soil bulk density for the loess deposit from Ganzi region, western Sichuan Plateau |
成婷1; 杨胜利1; 刘维明2![]() | |
2018 | |
Source Publication | 地球环境学报
![]() |
ISSN | 1674-9901 |
Volume | 9Issue:3Pages:230-237 |
Subtype | Article |
Contribution Rank | 2 |
Abstract | 川西高原一带黄土沉积广泛分布,研究该地区黄土-古土壤序列的容重对于理解黄土沉积过程,探讨青藏高原东部地区的环境演化具有重要意义.论文详细分析了甘孜地区末次间冰期以来的典型黄土-古土壤序列的容重变化,结果表明该区土壤容重在1.63 2.53 g · cm~(-3)变化,黄土地层中容重较大,平均为2.01 g · cm~(-3);古土壤地层中容重较小,平均为1.94 g · cm~(-3).土壤容重与磁化率、粒度<2 mum组分具有很好的负相关关系,而与平均粒径、粒度>63 mum组分呈明显正相关,可能表明了土壤化过程和沉积过程对土壤容重的影响;进一步的环境指标相关分析表明甘孜黄土-古土壤容重可以作为西风和高原冬季风变化的替代性指标.详细研究该区黄土的容重变化将有助于深入理解区域环流的演化过程和高原内部的干旱化历史. |
Other Abstract | Background, aim, and scope Loess deposits are widely distributed in the western Sichuan Plateau. Previous studies have focused on its origin, age, geochemistry, mineralogy, and its paleo-environmental significance. The bulk density characteristics of loess-paleosol sequences in this area has important significance for understanding the aeolian process of loess deposition and exploring the eastern Tibetan Plateau environmental evolution. However, few studies have been shown on the bulk density of the loess in this region. In this paper, a typical loess-paleosol sequence from Ganzi County was investigated in detailed to explore the characteristics and its paleoclimate significance of the soil bulk density of the loess-paleosol sequence on the Tibetan Plateau. Materials and methods Sampling site (31°37'13.02N, 99°58'52.95E; 3400 m) is located in northwest of Xinshiqu Village, Ganzi County, Sichuan Province (XS), and on the third terrace of the Yalong River. Measurements of bulk density, magnetic susceptibility and grain size are all carried out in the Ministry of Education Key Laboratory of Western China's Environmental Systems, Lanzhou University. The bulk density was measured by the oil-soaked method after samples were air dried. Each sample was measured twice to achieve the average value and 200 samples were analyzed for the entire profile. The magnetic susceptibility analysis was performed using British magnetization meter (Bartington MS2). Each sample was weighed, then stored in a nonmagnetic plastic box and measured twice to achieve the average value. Grain-size samples were analyzed using a Malvern Master Sizer 2000, with a size detection range of 0.02 2000 mum. Samples were pre-treated with 10% H_2O_2 and 10% HCl to remove organic matter and carbonates respectively, then washed by distilled water. After addition of 10 mL of 3.6% Na4P2O7·10H_2O, the samples were dispersed using an ultrasonic bath for 10 min before the measurement. AMS-14C dating was completed in Peking University AMS laboratory after sample pretreatment in the Lanzhou University laboratory. Optically stimulated luminescence dating used quartz mineral with the single aliquot regenerative dose protocol and measurements were completed in the luminescence dating laboratory, Institute of Mountain Hazards and Environment, CAS. Results Our results have shown that the soil bulk density of the XS section varies frequently with the depth since the last interglaciation, with a trend of high value in loess units and low value in paleosol units. It varies from 1.63 g · cm~(-3) to 2.53 g · cm~(-3) along the whole profile. The bulk density in loess units ranges between 1.67 2.48 g · cm~(-3), with an average of 2.01 g · cm~(-3). While the bulk density of the paleosol units ranges between 1.63 2.53 g · cm~(-3), with an average of 1.94 g · cm~(-3). The average bulk density of the XS loess-paleosol sequence is heavier than that of Luochuan section (1.25 1.86 g · cm~(-3)) and Baicaoyuan section (1.05 2.18 g · cm~(-3)) from the Chinese Loess Plateau. It is also much heavier than the loess deposit from the north slope of the western Kunlun Mountian (1.25 1.60 g · cm~(-3)). However, the bulk density of the Ganzi loess is quite similar to the Lingtai section (1.85 2.18 g · cm~(-3)) and Mangshan section (1.50 2.50 g · cm~(-3)) from the Loess Plateau. |
Keyword | 青藏高原 黄土- 古土壤 容重 甘孜 |
DOI | 10.7515/JEE182019 |
Indexed By | CSCD |
Language | 中文 |
CSCD ID | CSCD:6293349 |
Citation statistics | |
Document Type | 期刊论文 |
Identifier | http://ir.imde.ac.cn/handle/131551/23983 |
Collection | 山地灾害与地表过程重点实验室 |
Corresponding Author | 杨胜利 |
Affiliation | 1.兰州大学 西部环境教育部重点实验室,资源环境学院,兰州 730000; 2.中国科学院水利部成都山地灾害与环境研究所,成都 610041 |
Recommended Citation GB/T 7714 | 成婷,杨胜利,刘维明,等. 川西高原甘孜黄土- 古土壤容重的特征及其古环境意义[J]. 地球环境学报,2018,9(3):230-237. |
APA | 成婷.,杨胜利.,刘维明.,李帅.,梁敏豪.,...&陈慧.(2018).川西高原甘孜黄土- 古土壤容重的特征及其古环境意义.地球环境学报,9(3),230-237. |
MLA | 成婷,et al."川西高原甘孜黄土- 古土壤容重的特征及其古环境意义".地球环境学报 9.3(2018):230-237. |
Files in This Item: | ||||||
File Name/Size | DocType | Version | Access | License | ||
川西高原甘孜黄土_古土壤容重的特征及其古(1100KB) | 期刊论文 | 出版稿 | 开放获取 | CC BY-NC-SA | View Application Full Text |
Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.
Edit Comment