鹤庆钻孔沉积物总有机碳、氮含量测定的前处理方法及其环境意义

卢凤艳; 安芷生

鹤庆钻孔沉积物总有机碳、氮含量测定的前处理方法及其环境意义

卢凤艳^{1, 2,},
安芷生¹

1.
中国科学院地球环境研究所黄土与第四纪国家重点实验室, 陕西西安 710075
2.
中国科学院研究生院, 北京 100039

详细信息

作者简介:
卢凤艳(1980-), 女, 在读博士研究生, 主要从事古环境变化研究。E-mail:lfy@ieecas.cn

中图分类号: P588.2
计量
- 文章访问数: 105
- HTML全文浏览量: 58
- PDF下载量: 9
- 被引次数: 0
出版历程
- 收稿日期: 2010-03-09
- 刊出日期: 2010-12-28

PRETREATMENT METHODS FOR ANALYZING THE TOTAL ORGANIC CARBON AND NITROGEN CONTENTS OF HEQING CORE SEDIMENTS AND THEIR ENVIRONMENTAL SIGNIFICANCES

Lu Feng-yan^{1, 2
,},
An Zhi-sheng¹

1.
State Key Lab. Of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710075
2.
Graduate School of Chinese Academy of Sciences, Beijing 100049

摘要

摘要: 湖泊沉积物中的总有机碳含量(TOC)、总有机氮含量(TN)和碳氮比值(C/N)已被广泛应用于第四纪湖泊古环境研究中。对湖泊沉积物样品进行TOC和TN测定前, 首先要有效去除沉积物中的无机碳酸盐, 同时较好地保留有机质组分, 才能使实验结果较准确地反映古气候环境的变化。选取鹤庆钻孔不同深度的不同岩性样品, 分别进行粒度、盐酸浓度、洗除残留酸方法等对去除碳酸盐和总有机碳测定结果影响的前处理条件实验, 根据测得的TOC、TN和C/N, 结合总无机碳酸盐含量(TIC), 确定了鹤庆钻孔沉积物有机碳含量测定的前处理方法:室温条件下, 将磨得足够细(无需过筛处理)的样品与足量浓度为2mol/L盐酸充分反应24小时, 期间超声震荡3次, 采用离心加速沉淀的方法清洗酸处理样品至中性, 烘干, 研磨均匀上机测定。结果显示, 该流程可有效去除沉积物中的无机碳酸盐, 测得的TOC、TN数值具有很好的稳定性和可重复性。在此基础上测定了鹤庆钻孔沉积物样品的TOC、C/N和TIC, 它们间存在很好的正相关关系, 指示了西南季风强度的变化。
- 总有机碳 /
- 碳氮比值 /
- 鹤庆盆地 /
- 碳酸盐 /
- 西南季风
Abstract: Total organic carbon content (TOC), Total organic nitrogen content (TN) and their ration (C/N) of lacustrine sediments have been widely used in the Quaternary palaeoenvironment researches. Before measuring the TOC and TN of the sediments, the first important step is to effectively remove the inorganic carbonate, and preserve organic carbon well at the same time, which is the guarantee to good experiment results and accurate palaeoenvironment reconstruction. In order to apply a proper experimental procedure to the Heqing core sediments in Yunnan province, different lithological sediment samples from different depths are used to examine the influence of pretreatment methods, including grain size, the concentration of hydrochloric acid (HCl), and the method of washing the residual acid, on the analysis of total organic carbon content. According to the results of TOC, TN, C/N, and the total inorganic carbonate content (TIC), the pretreatment procedure of Heqing core sediments prior to TOC analysis is established as the followings:under normal condition, a sediment sample is grinded to be uniform and fine (no sieving process), which reacts with enough HCl whose concentration is 2mol/L for 24 hours; then centrifugal acceleration method is employed to cleaning the treated sample by acid to be neutral. This procedure can effectively remove the inorganic carbonate from the sediments, and the results of TOC and TN show good stability and reproducibility. The obtained sequences of TOC, TN, and C/N show good correlation, which all imply the intensity changes of the southwest monsoon.
- TOC /
- C/N /
- Heqing basin /
- inorganic carbonate /
- southwest monsoon

HTML全文

图 1 鹤庆钻孔TOC、TN、C/N和TIC的深度变化序列

Figure 1. Depth variability of TOC、TN、C/N and TIC from Heqing core

下载: 全尺寸图片幻灯片

图 2 鹤庆钻孔沉积序列中TOC与C/N和TIC的相关关系

Figure 2. The relationship of TOC, C/N and TIC of Heqing core

下载: 全尺寸图片幻灯片

表 1 样品深度及岩性描述

Table 1. Depths of the samples and their lithology

表 2 不同实验条件组合下TOC、TN、C/N和TIC实验分析结果

Table 2. The results of TOC、TN、C/N and TIC under different experimental conditions

参考文献(19)

[1]	Dean W. The carbon cycle and biogeochemical dynamics in lake sediments[J]. Journal of paleolimnology, 1999, 21 (4):375~393. doi: 10.1023/A:1008066118210
[2]	Meyers P, Ishiwatari R. Lacustrine organic geochemistry. An overview of indicators of organic matter sources and diagenesis in lake sediments[J]. Organic Geochemistry, 1993, 20 (7):867~900. doi: 10.1016/0146-6380(93)90100-P
[3]	King P, Kenned H, Newton P, et al. Analysis of total and organic carbon and total nitrogen in settling oceanic particles and a marine sediment:an interlaboratory comparison[J]. Marine chemistry, 1998, 60:203~216. doi: 10.1016/S0304-4203(97)00106-0
[4]	Dean W. Determination of carbonate and organic matter in calcareous sediments and sedimentary rocks by loss on ignition: comparison with other methods[J]. Journal of Sedimentary Petrology, 1974, 44 (1):242~248. http://cn.bing.com/academic/profile?id=79fbc1e17946dd5e70b53be34d67e9f2&encoded=0&v=paper_preview&mkt=zh-cn
[5]	Hirota J, Szyper J. Separation of total particulate carbon into inorganic and organic components[J]. Limnology and Oceanography, 1975, 20 (5):896~900. doi: 10.4319/lo.1975.20.5.0896
[6]	解启来, 周中毅, 陆明勇.碳酸盐矿物结合有机质——一种重要的成烃物质[J].矿物学报, 2000, 20 (1):59~ 62. doi: 10.3321/j.issn:1000-4734.2000.01.011 Xie Qilai, Zhou Zhongyi, Lu Mingyong. Organic matter enclosed in carbonate minerals-a kind of important hydrocarbon-producing matter[J]. Acta Mineralogica Sinica, 2000, 20 (1):59~62. doi: 10.3321/j.issn:1000-4734.2000.01.011
[7]	Froelich P. Analysis of organic carbon in marine sediments[J]. Limnology and Oceanography, 1980, 564~572. doi: 10.4319/lo.1980.25.3.0564/full
[8]	Gibbs R. Effect of combustion temperature and time, and of the oxidation agent used in organic carbon and nitrogen analyses of sediments and dissolved organic material[J]. Journal of Sedimentary Petrology, 1977, 47 (2):547~550. http://cn.bing.com/academic/profile?id=3d35441bb7877122354f2d06be3769e6&encoded=0&v=paper_preview&mkt=zh-cn
[9]	贾蓉芬, 邢福建, 赵林, 等. 从渭南剖面有机质类型的差异探讨黄土地区湿度的演变趋势[J]. 地球化学, 1995, 24 (C): 66~74. http://kns.cnki.net/KCMS/detail/detail.aspx?filename=DQHX5S1.007&dbname=CJFD&dbcode=CJFQ Jia Rongfen, Xing Fujian, Zhao Lin, Wen Qizhong. Approach to humidity evolution since 0. 14Ma in loess area from typr differnce of organic matter in Weina loess section[J]. Geochimica, 1995, 24 (C): 66~74. http://kns.cnki.net/KCMS/detail/detail.aspx?filename=DQHX5S1.007&dbname=CJFD&dbcode=CJFQ
[10]	Chen J, Wang F, et al. Environmental records of carbon in recent lake sediments[J]. Science in China Series D:Earth Sciences, 2002, 45 (10):875~884. doi: 10.1360/02yd9086
[11]	徐新文, 强小科, 安芷生, 等.鹤庆盆地湖相岩心磁化率记录及其古环境意义[J].地质力学学报, 2010, 16 (4):372~382. doi: 10.3969/j.issn.1006-6616.2010.04.005 XU Xinwen, QIANG Xiaoke, AN Zhisheng, et al. Magnetic Susceptibility Of Heqing Drill Core And Its Palaeoenvironmental Implications[J]. Journal of Geomechanic, 2010, 16 (4):372~382. doi: 10.3969/j.issn.1006-6616.2010.04.005
[12]	曹蕴宁, 刘卫国, 宁有丰, 等.土壤有机碳同位素样品制备过程的影响因素讨论[J].地球化学, 2005, 34 (4): 91~100. http://d.old.wanfangdata.com.cn/Periodical/dqhx200504011 Cao Yunning, Liu Weiguo, Ning Youfeng, et al. Effects of soil sample preparation process on d13C of organic matter[J]. Geochimica, 2005, 34 (4):91~100. http://d.old.wanfangdata.com.cn/Periodical/dqhx200504011
[13]	喻涛, 李春园.盐酸, 温度, 时间及粒径对海洋沉积物碳酸盐去除的影响[J].热带海洋学报, 2006, 25 (6):33 ~38. doi: 10.3969/j.issn.1009-5470.2006.06.006 Yu Tao, Li Chunyuan. Effects of hydrochloric acid, temperature, time and grain size on carbonate removal from marine sediments in norhtern South China sea[J]. Journal of Tropical Oceanography, 2006, 25 (6):33~38. doi: 10.3969/j.issn.1009-5470.2006.06.006
[14]	吴夏, 黄俊华, 白晓, 等.沉积岩总有机质碳同位素分析的前处理影响[J].地球学报, 2008, 29 (6):677~683. doi: 10.3321/j.issn:1006-3021.2008.06.003 Wu Xia, Huang Houhua, Bai Xiao, et al. Samole-pretreatment effects on analytical results of total organic carbon isotopes in sedimentary rocks[J]. Acta Geoscientica Sinica, 2008, 29 (6):677~683. doi: 10.3321/j.issn:1006-3021.2008.06.003
[15]	云南植被编写组.云南植被[M].北京:科学出版社, 1987.759~774. Compiling Group of Yunnan Vegetation. Vegetation of Yunnan[M]. Beijing:Science Press, 1987.759~774.
[16]	王苏民, 吉磊, 羊向东, 等.呼伦湖:古湖泊学研究[M].合肥:中国科学技术大学出版社, 1995.1~125. Wang Sumin, Ji Lei, Yang Xiangdong et al., Palaeolimnology of Hulun Lake[M]. Hefei:Press of China University of Sciences & Technology, 1995.1~125.
[17]	MEYERS P A. Preservation of elemental and isotopic source identification of sedimentary organic matter[J]. Chemical Geology, 1994, 114 (3~4):289~302. doi: 10.1016/0009-2541(94)90059-0
[18]	Krishnamurthy R V, Bhattachary S K, Kusumgar S. Palaeoclimatic changes deduced from 13C/12C and C/N ratios of Karewa lake sediments, India[J]. Nature, 1986, 323 (6084):150~152. doi: 10.1038/323150a0
[19]	Stuiver M. Climate versus changes in 13C content of the organic component of lake sediments during the Late Quarternary [J]. Quaternary Research, 1975, 5 (2):251~262. doi: 10.1016/0033-5894(75)90027-7