Distributions of amino acids and their indications for the degradation of dissolved organic matter in the northern South China Sea
-
摘要: 于2015年6月对南海北部海区5个断面共26个站位海水中溶解态氨基酸(THAA)、溶解有机碳(DOC)和叶绿素a(Chl a)的浓度进行了科学调查。结果表明:夏季南海北部海水中THAA的浓度范围为0.40~1.95 μmol/L,平均值为(0.80±0.40) μmol/L,THAA的水平分布总体上体现出近岸高、远海低的特点,表明陆源输入对南海北部海域表层THAA分布有重要影响。THAA在断面上的垂直分布呈现出由近岸至远岸、由表层至底层逐渐降低的趋势。THAA浓度与两种D型氨基酸(D-谷氨酸:D-Glu和D-丙氨酸:D-Ala)含量之间存在显著负相关性,与天门冬氨酸/β-丙氨酸(Asp/β-Ala)和谷氨酸/γ-氨基丁酸(Glu/γ-Aba)比值之间存在显著正相关性,表明细菌的消耗是影响南海海水中THAA浓度的重要因素。D-Ala作为细菌肽聚糖中相对稳定的氨基酸,根据其占DOC的含量估算南海海水中的细菌源有机碳对DOC的贡献率为(29.32±14.32)%,其水平分布显示出近岸低、远岸高的特点;而其垂直分布则呈现出从表层至底层逐渐增加的趋势。THAA占DOC百分比(THAA-C%)的变化范围为1.02%~5.49%,平均值为(2.97±1.38)%。THAA-C%、活性因子和降解因子的高值均出现在珠江口外围区域。随着海水深度增加3种降解因子的数值均显著降低,这表明底层海水中有机物比表层海水中的有机物降解程度更大。Abstract: Concentrations of dissolved amino acid (THAA), dissolved organic carbon (DOC) and chlorophyll a(Chl a) were determined in five transects of the northern South China Sea (NSCS) in June 2015. The results showed that the concentrations of THAA ranged from 0.40 to 1.95 μmol/L, with an average of (0.80±0.40) μmol/L. THAA concentrations exhibited a decreasing trend from the nearshore to offshore stations, indicating that terrestrial input plays an important role in affecting the distributions of THAA. The vertical distribution of THAA concentrations displayed a decreasing trend from the surface layer to the bottom layer. The present study found that the concentrations of THAA were negatively correlated to the D-amino acids (D-Glu and D-Ala), but positively correlated to Asp/β-Ala and Glu/γ-Aba ratios. Our results indicated that the bacterial consumption was an important factor influencing the concentration of THAA in the NSCS. The contribution of bacterial organic carbon to DOC was (29.32 ±14.32)% in the NSCS, exhibiting increasing trends from the nearshore to offshore sites and from the surface waters to the bottom waters. High values of carbon normalized yields of amino acids (THAA-C%), reactivity index and degradation index (DI) were found in the area near the Zhujiang Estuary. With the increasing of the water depth, the values of the degradation factors were significantly decreased, reflecting the higher degradation extent of organic matter in the bottom waters.
-
Key words:
- dissolved amino acid /
- dissolved organic carbon /
- bacterial degradation /
- South China Sea
-
Cowie G L, Hedges J I. Biochemical indicators of diagenetic alteration in natural organic matter mixtures[J]. Nature, 1994, 369(6478):304-307. Bada J L. Racemization of amino acids in nature[J]. Interdisciplinary Science Reviews, 1982, 7(1):30-46. Dauwe B, Middelburg J J, Herman P M J, et al. Linking diagenetic alteration of amino acids and bulk organic matter reactivity[J]. Limnology and Oceanography, 1999, 44(7):1809-1814. Dauwe B, Middelburg J J. Amino acids and hexosamines as indicators of organic matter degradation state in North Sea sediments[J]. Limnology and Oceanography, 1998, 43(5):782-798. Huang X P, Huang L M, Yue W Z. The characteristics of nutrients and eutrophication in the Pearl River estuary, South China[J]. Marine Pollution Bulletin, 2003, 47(1/6):30-36. 陈建芳, 金海燕, 刘小涯, 等. 黄海和东海沉积物有机质活性及营养盐再生潜力初探[J]. 地球化学, 2005, 34(4):387-394. Chen Jianfang, Jin Haiyan, Liu Xiaoya, et al. Reactivity and potential regenerating capability of sedimentary organic matter in the Yellow Sea and the East China Sea[J]. Geochimica, 2005, 34(4):387-394. 程国胜, 孙佳东, 俎婷婷, 等. 2011年夏季南海北部海区水团分析[J]. 热带海洋学报, 2014, 33(3):10-16. Cheng Guosheng, Sun Jiadong, Zu Tingting, et al. Analysis of water masses in the northern South China Sea in summer 2011[J]. Journal of Tropical Oceanography, 2014, 33(3):10-16. Kaiser K, Benner R. Erratum:major bacterial contribution to the ocean reservoir of detrital organic carbon and nitrogen[J]. Limnology and Oceanography, 2008, 53(3):1192. 李烈英, 张星君, 纪明侯. 东海海域海水中颗粒氨基酸(PAA)的组成与含量的分布调查研究[J]. 海洋科学集刊, 2004:100-105. Li Lieying, Zhang Xingjun, Ji Minghou. Studies on the distribution of components and contents of particulate amino acids in sea water of the East China Sea[J]. Studia Marina Sinica, 2004:100-105. Wu Ying, Dittmar T, Ludwichowski K U, et al. Tracing suspended organic nitrogen from the Yangtze River catchment into the East China Sea[J]. Marine Chemistry, 2007, 107(3):367-377. 王丽玲, 胡建芳, 唐建辉. 中国近海表层沉积物中氨基酸组成特征及生物地球化学意义[J]. 海洋学报, 2009, 31(6):161-169. Wang Liling, Hu Jianfang, Tang Jianhui. Amino acid composition and its biogeochemistry implications of surface sediments in coastal areas of China[J]. Haiyang Xuebao, 2009, 31(6):161-169. 刘宗广, 吴莹, 胡俊, 等. 东海陆架典型断面颗粒态氨基酸的分布及控制因素分析[J]. 海洋与湖沼, 2013, 44(3):563-569. Liu Zongguang, Wu Ying, Hu Jun, et al. Distribution of particulate amino acids and its controlling factors in the PN transection of the East China Sea Shelf[J]. Oceanologia et Limnologia Sinica, 2013, 44(3):563-569. Yang Guipeng, Yan Chen, Gao Xianchi. Distribution of dissolved free amino acids, dissolved inorganic nitrogen and chlorophyll a in the surface microlayer and subsurface water of the Yellow Sea, China[J]. Continental Shelf Research, 2009, 29(14):1737-1747. 陈岩, 杨桂朋. 春季北黄海表层海水中溶解游离氨基酸的分布与组成研究[J]. 中国海洋大学学报, 2010, 40(7):93-98. Chen Yan, Yang Guipeng. Study on dissolved free amino acid (DFAA) in the surface water of the North Yellow Sea[J]. Periodical of Ocean University of China, 2010, 40(7):93-98. Chen Yan, Yang Guipeng, Liu Li, et al. Sources, behaviors and degradation of dissolved organic matter in the East China Sea[J]. Journal of Marine Systems, 2016, 155:84-97. 夏清艳, 杨桂朋, 高先池, 等. 南海北部表层海水中溶解氨基酸的分布与组成研究[J]. 海洋环境科学, 2011, 30(6):774-779. Xia Qingyan, Yang Guipeng, Gao Xianchi, et al. Distribution and composition of dissolved amino acids in surface water of northern South China Sea[J]. Marine Environmental Science, 2011, 30(6):774-779. Fitznar H P, Lobbes J M, Kattner G. Determination of enantiomeric amino acids with high-performance liquid chromatography and pre-column derivatisation with o-phthaldialdehyde and N-isobutyrylcysteine in seawater and fossil samples (mollusks)[J]. Journal of Chromatography A, 1999, 832(1/2):123-132. Kaiser K, Benner R. Erratum:hydrolysis-induced racemization of amino acids[J]. Limnology and Oceanography:Methods, 2005, 3(8):318-325. Jennerjahn T C, Ittekkot V. Organic matter in sediments in the mangrove areas and adjacent continental margins of Brazil:I. Amino acids and hexosamines[J]. Oceanologica Acta, 1997, 20(2):359-369. Wu C R, Chiang T L. Mesoscale eddies in the northern South China Sea[J]. Deep-Sea Research Part Ⅱ:Topical Studies in Oceanography, 2007, 54(14/15):1575-1588. 王朋, 陈岩, 杨桂朋, 等. 春季中国南黄海与东海海水中溶解氨基酸的分布和组成[J]. 海洋环境科学, 2015, 34(2):217-224. Wang Peng, Chen Yan, Yang Guipeng, et al. Distribution and composition of dissolved amino acids in the East China Sea and the Yellow Sea during spring[J]. Marine Environmental Science, 2015, 34(2):217-224. Chen Yan, Yang Guipeng, Wu Guanwei, et al. Concentration and characterization of dissolved organic matter in the surface microlayer and subsurface water of the Bohai Sea, China[J]. Continental Shelf Research, 2013, 52(1):97-107. McCarthy M D, Hedges J I, Benner R. Major bacterial contribution to marine dissolved organic nitrogen[J]. Science, 1998, 281(5374):231-234. Kawasaki N, Benner R. Bacterial release of dissolved organic matter during cell growth and decline:molecular origin and composition[J]. Limnology and Oceanography, 2006, 51(5):2170-2180. Lam H, Oh D C, Cava F, et al. D-amino acids govern stationary phase cell wall remodeling in bacteria[J]. Science, 2009, 325(5947):1552-1555. Bourgoin L H, Tremblay L. Bacterial reworking of terrigenous and marine organic matter in estuarine water columns and sediments[J]. Geochimica et Cosmochimica Acta, 2010, 74(19):5593-5609. Ittekkot V, Brockmann U, Michaelis W, et al. Dissolved free and combined carbohydrates during a phytoplankton bloom in the northern North Sea[J]. Marine Ecology Progress Series, 1981, 4(3):299-305. Meon B, Kirchman D L. Dynamics and molecular composition of dissolved organic material during experimental phytoplankton blooms[J]. Marine Chemistry, 2001, 75(3):185-199. Fernandes L. Origin and biochemical cycling of particulate nitrogen in the Mandovi estuary[J]. Estuarine, Coastal and Shelf Science, 2011, 94(3):291-298. 龚词, 杨桂朋. 夏季南海北部溶解碳水化合物浓度分布[J]. 海洋环境科学, 2017, 36(3):321-327. Gong Ci, Yang Guipeng. Distributions of dissolved carbohydrates in the northern South China Sea during summer[J]. Marine Environmental Science, 2017, 36(3):321-327. 袁梁英. 南海北部营养盐结构特征[D]. 厦门:厦门大学, 2005. Yuan Liangying. Distribution and characteristics of nutrients in the northern South China Sea[D]. Xiamen:Xiamen University, 2005. Shen Yuan, Fichot C G, Liang Shengkang, et al. Biological hot spots and the accumulation of marine dissolved organic matter in a highly productive ocean margin[J]. Limnology and Oceanography, 2016, 61(4):1287-1300. Myklestad S, Haug A. Production of carbohydrates by the marine diatom Chaetoceros affinis var. willei (Gran) Hustedt. I. Effect of the concentration of nutrients in the culture medium[J]. Journal of Experimental Marine Biology and Ecology, 1972, 9(2):125-136. Jiang Yuelu, Yoshida T, Quigg A. Photosynthetic performance, lipid production and biomass composition in response to nitrogen limitation in marine microalgae[J]. Plant Physiology and Biochemistry, 2012, 54:70-77.
点击查看大图
计量
- 文章访问数: 849
- HTML全文浏览量: 15
- PDF下载量: 495
- 被引次数: 0