钦州湾河流沉积物中镭的解吸行为

罗浩; 李林蔚; 王锦龙; 钟强强; 杜金洲

doi:10.3969/j.issn.0253-4193.2019.04.003

钦州湾河流沉积物中镭的解吸行为

doi: 10.3969/j.issn.0253-4193.2019.04.003

华东师范大学河口海岸学国家重点实验室, 上海 200062

基金项目: 国家自然科学面上基金（41576083）。

计量
- 文章访问数: 617
- HTML全文浏览量: 34
- PDF下载量: 271
- 被引次数: 0
出版历程
- 收稿日期: 2018-02-13
- 修回日期: 2018-03-20

The desorption of radium isotopes in river sediments in Qinzhou Bay

State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200062, China

摘要

摘要: 放射性镭同位素在海底地下水排放（SGD）等海洋物质变化过程的研究中具有优良的示踪作用，估算SGD通量时需要计算河流悬浮颗粒物的解吸通量。因此，对河流沉积物/悬浮颗粒物中镭同位素解吸行为的研究不可或缺，而目前对于粒度较小范围内镭同位素的解吸特征及其机理的研究依然不足。本文选用钦州湾河流沉积物，通过室内实验探究粒度和盐度对沉积物中镭同位素解吸行为的影响。结果表明，在沉积物平均粒径0.9~136.0 μm范围内，随着粒径增大，沉积物中镭同位素在海水（盐度为33.9）中解吸活度逐渐减小，且变化趋势也逐渐变缓，平均粒径大于43.7 μm后，解吸量几乎不变；在海水盐度4.9~33.9范围内，随着盐度增大，沉积物中镭同位素解吸活度逐渐增大，盐度大于24.9后，解吸量趋于不变。本文创新性地建立了沉积物表面分形结构的镭解吸理论模型，拟合得到钦州湾河流沉积物表面最大可交换态²²⁴Ra、²²⁶Ra和²²⁸Ra活度分别为1.13 dpm/g、0.17 dpm/g和0.85 dpm/g，以干重计；沉积物中²²⁴Ra、²²⁶Ra和²²⁸Ra最大解吸比分别为30%、7%和18%。钦州湾河流沉积物颗粒表面最大可交换态²²⁴Ra和²²⁶Ra活度分别处于全球中等水平和较低水平，而其最大解吸比分别处于全球较高水平和较低水平。本研究结果有助于更好地理解镭同位素的解吸行为，以帮助更准确地估算SGD通量。
- 钦州湾 /
- 镭同位素 /
- 河流沉积物 /
- 解吸行为
Abstract: Radium isotopes are one of the useful tracers to study the submarine groundwater discharge (SGD) processes. It is indispensable to estimate the desorption flux of the river sediment when estimate SGD flux. Thus, it is necessary to study the desorption behavior of the radium isotopes in river sediment/suspended particles, especially for the smaller size range of sediment. In the present work, the effects of grain sizes of sediments and salinities of sea water from the Qinzhou Bay on the desorption of radium isotopes were investigated by laboratory experiments. The results show that, within the grain size range of 0.9-136.0 μm, the desorption amounts of radium isotopes from the sediment to seawater (salinity 33.9) decrease with the grain size increase, and the desorption amounts keep almost constant when the grain size is larger than 43.7 μm. Within the salinity range of 4.9-33.9, the desorption amounts of radium isotopes from sediments gradually increase with the salinity increasing until the salinity reaches 24.9. By establishing creatively the radium desorption model using the sediment surface fractal structure theory, the maximum exchangeable activities of ²²⁴Ra, ²²⁶Ra and ²²⁸Ra from the river sediment of Qinzhou Bay are estimated to be 1.13 dpm/g, 0.17 dpm/g and 0.85 dpm/g, respectively; and the concerned maximum desorption ratios are 30%, 7% and 18%. Compared to those from other estuarine/coastal regions, the maximum exchangeable activities of ²²⁴Ra and ²²⁶Ra from the river sediments in Qinzhou Bay are in the middle or low ranges, while the maximum desorption ratios are in the higher or lower levels, respectively. The results of this study is expected to be useful to better understand the desorption behavior of radium isotopes and estimate accurately SGD flux.
- Qinzhou Bay /
- radium isotope /
- river sediment /
- the desorption behavior

HTML全文

参考文献(32)

Moore W S. The subterranean estuary:a reaction zone of ground water and sea water[J]. Marine Chemistry, 1999, 65(1/2):111-125.

Moore W S. Large groundwater inputs to coastal waters revealed by ²²⁶Ra enrichments[J]. Nature, 1996, 380(6575):612-614.

Burnett W C, Bokuniewicz H, Huettel M, et al. Groundwater and pore water inputs to the coastal zone[J]. Biogeochemistry, 2003, 66(1/2):3-33.

Su Ni, Du Jinzhou, Moore W S, et al. An examination of groundwater discharge and the associated nutrient fluxes into the estuaries of eastern Hainan Island, China using ²²⁶Ra[J]. Science of the Total Environment, 2011, 409(19):3909-3918.

Ji Tao, Du Jinzhou, Moore W S, et al. Nutrient inputs to a Lagoon through submarine groundwater discharge:the case of Laoye Lagoon, Hainan, China[J]. Journal of Marine Systems, 2013, 111-112:253-262.

Wang Xilong, Du Jinzhou, Ji Tao, et al. An estimation of nutrient fluxes via submarine groundwater discharge into the Sanggou Bay-A typical multi-species culture ecosystem in China[J]. Marine Chemistry, 2014, 167:113-122.

Ye Qi, Liu Jianan, Du Jinzhou, et al. Bacterial diversity in submarine groundwater along the coasts of the Yellow Sea[J]. Frontiers in Microbiology, 2016, 6:1519.

Tait D R, Maher D T, Sanders C J, et al. Radium-derived porewater exchange and dissolved N and P fluxes in mangroves[J]. Geochimica et Cosmochimica Acta, 2017, 200:295-309.

王希龙, 杜金洲, 张经. 基于²²³Ra和²²⁴Ra的桑沟湾海底地下水排放通量[J]. 海洋学报, 2017, 39(4):16-27. Wang Xilong, Du Jinzhou, Zhang Jing. Submarine groundwater discharge into Sanggou Bay traced by ²²³Ra and ²²⁴Ra[J]. Acta Oceanologica Sinica, 2017, 39(4):16-27.

Burnett W C, Aggarwal P K, Aureli A, et al. Quantifying submarine groundwater discharge in the coastal zone via multiple methods[J]. Science of the Total Environment, 2006, 367(2/3):498-543.

Hancock G J, Murray A S. Source and distribution of dissolved radium in the Bega River estuary, Southeastern Australia[J]. Earth and Planetary Science Letters, 1996, 138(1/4):145-155.

Gonneea M E, Morris P J, Dulaiova H, et al. New perspectives on radium behavior within a subterranean estuary[J]. Marine Chemistry, 2008, 109(3/4):250-267.

Moore W S. Sources and fluxes of submarine groundwater discharge delineated by radium isotopes[J]. Biogeochemistry, 2003, 66(1/2):75-93.

Moore W S, Astwood H, Lindstrom C. Radium isotopes in coastal waters on the Amazon shelf[J]. Geochimica et Cosmochimica Acta, 1995, 59(20):4285-4298.

Beck A J, Rapaglia J P, Cochran J K, et al. Radium mass-balance in Jamaica Bay, NY:evidence for a substantial flux of submarine groundwater[J]. Marine Chemistry, 2007, 106(3/4):419-441.

郭占荣, 黄磊, 袁晓婕, 等. 用镭同位素评价九龙江河口区的地下水输入[J]. 水科学进展, 2011, 22(1):118-125. Guo Zhanrong, Huang Lei, Yuan Xiaojie, et al. Estimating submarine groundwater discharge to the Jiulong River estuary using Ra isotopes[J]. Advances in Water Science, 2011, 22(1):118-125.

Li Yuanhui, Chan L H. Desorption of Ba and ²²⁶Ra from river-borne sediments in the Hudson estuary[J]. Earth and Planetary Science Letters, 1979, 43(3):343-350.

Hancock G J. The effect of salinity on the concentrations of radium and thorium in sediments[D]. Australian:Australian National University, 1993.

Webster I T, Hancock G J, Murray A S. Modelling the effect of salinity on radium desorption from sediments[J]. Geochimica et Cosmochimica Acta, 1995, 59(12):2469-2476.

Sun Hongbing, Semkow T M. Mobilization of thorium, radium and radon radionuclides in ground water by successive alpha-recoils[J]. Journal of Hydrology, 1998, 205(1/2):126-136.

Beck A J, Cochran M A. Controls on solid-solution partitioning of radium in saturated marine sands[J]. Marine Chemistry, 2013, 156:38-48.

谷河泉, 赵峰, 季韬, 等. 盐度对镭同位素在海南红树林沉积物解吸行为的影响[J]. 海洋与湖沼, 2015, 46(1):65-76. Gu Hequan, Zhao Feng, Ji Tao, et al. Effect of salinity on radium desorption from sediments in mangrove wetland, Hainan[J]. Oceanologia et Limnologia Sinica, 2015, 46(1):56-76.

孔凡翠, 沙占江, 杜金洲, 等. 青海湖西岸镭同位素的解吸和扩散特征[J]. 湖泊科学, 2016, 28(5):1103-1114. Kong Fancui, Sha Zhanjiang, Du Jinzhou, et al. Desorption and diffusion characteristics of radium isotopes from particles in the western part of Lake Qinghai[J]. Journal of Lake Sciences, 2016, 28(5):1103-1114.

夏冬, 米铁柱, 甄毓, 等. 海水对含水层沉积物中镭解吸的模拟实验[J]. 海洋环境科学, 2016, 35(1):63-67. Xia Dong, Mi Tiezhu, Zhen Yu, et al. Simulating the process of radium desorption from coastal aquifer sediments by seawater[J]. Marine Environmental Science, 2016, 35(1):63-67.

袁晓婕, 郭占荣, 刘洁, 等. 咸水环境下沉积物中镭的解吸特点[J]. 地球学报, 2014, 35(5):582-588. Yuan Xiaojie, Guo Zhanrong, Liu Jie, et al. Characteristics of radium desorption from sediments in the salt water environment[J]. Acta Geoscientica Sinica, 2014, 35(5):582-588.

林鸿溢, 李映雪. 分形论:奇异性探索[M]. 北京:北京理工大学出版社, 1992. Lin Hongyi, Li Yingxue. Fractal Theory:Singularity Exploration[M]. Beijing:Beijing Insitute of Technology, 1992.

Moore W S, Arnold R. Measurement of ²²³Ra and ²²⁴Ra in coastal waters using a delayed coincidence counter[J]. Journal of Geophysical Research:Oceans, 1996, 101(C1):1321-1329.

Moore W S. Fifteen years experience in measuring ²²⁴Ra and ²²³Ra by delayed-coincidence counting[J]. Marine Chemistry, 2008, 109(3/4):188-197.

Wang Jinlong, Du Jinzhou, Baskaran M, et al. Mobile mud dynamics in the East China Sea elucidated using ²¹⁰Pb, ¹³⁷Cs, ⁷Be, and ²³⁴Th as tracers[J]. Journal of Geophysical Research:Oceans, 2016, 121(1):224-239.

Sayles F L, Mangelsdorf Jr P C. The equilibration of clay minerals with sea water:exchange reactions[J]. Geochimica et Cosmochimica Acta, 1977, 41(7):951-960.

Elsinger R J, Moore W S. ²²⁶Ra and ²²⁸Ra in the mixing zones of the Pee Dee River-Winyah Bay, Yangtze River and Delaware Bay Estuaries[J]. Estuarine, Coastal and Shelf Science, 1984, 18(6):601-613.

Rama, Moore W S. Using the radium quartet for evaluating groundwater input and water exchange in salt marshes[J]. Geochimica et Cosmochimica Acta, 1996, 60(23):4645-4652.

施引文献

资源附件(0)

访问统计