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1.
秋季东海溶解态和颗粒态氨基酸的组成与分布 总被引：1，自引：0，他引：1
本文对2012年秋季中国东海31个站位的海水样品中溶解态氨基酸(THAA)和颗粒态氨基酸(PAA)的组成与分布进行了研究。结果表明:表层海水中溶解游离氨基酸(DFAA)的平均浓度为(0.12±0.04)μmol/L(0.06—0.19μmol/L),溶解结合氨基酸(DCAA)的平均浓度为(0.61±0.51)μmol/L(0.15—1.79μmol/L),PAA的平均浓度为(0.11±0.06)μmol/L(0.02—0.27μmol/L)。THAA的水平分布特点大致为近岸高、远岸低;PAA的水平分布特点是近岸海域向远海海域分布呈现逐渐减小的趋势。THAA的垂直分布特点是由表层向底层逐渐降低。DCAA、PAA与chl a有很好的相关性,而DFAA与chl a的相关性不明显。东海表层海水中THAA的主要组分是天门冬氨酸、谷氨酸、丝氨酸、甘氨酸、苏氨酸及丙氨酸,PAA的主要组分是天门冬氨酸、谷氨酸、丝氨酸、甘氨酸、丙氨酸及亮氨酸。在表层海水中氨基酸是作为一个整体而对海洋生物地球化学过程产生影响的。 相似文献
2.
于2021年8月对珠江口及海南岛东南海域海水中的总溶解态氨基酸(THAA)、溶解有机碳(DOC)、有机氮(TN)和叶绿素a(Chl a)的浓度及分布进行了系统的调查研究。结果表明,调查站位海水中THAA的浓度范围为0.68～4.22μmol/L,平均浓度为(1.69±0.98)μmol/L,呈现近岸高、远岸低的分布趋势;垂直分布上,氨基酸浓度均呈现出随深度增加逐渐减小的特征。THAA浓度分布与天冬氨酸(Asp)/β-丙氨酸(β-Ala)和谷氨酸(Glu)/γ-氨基丁酸(γ-Aba)的比值具有显著正相关性,表明细菌活动对THAA的分布以及降解有重要影响。细菌源有机碳对DOC的贡献率约(13.04%±4.50%),呈现出近岸低于远岸、表层高于底层的特征。氨基酸中碳对有机碳的贡献率(THAA-C%)的分布趋势为近岸低于远海,说明近岸站位有机物降解程度更大。降解指数(DI)和活性指数(RI)也和THAA-C%呈现了相似的分布趋势,在调查海域的东部和珠江口近岸海域出现了高值区。垂直方向上,珠江口附近的S8—S14断面底层相对于表层降解因子的值更低,表明底层海水中的有机物降解程度更高,而海南岛东南... 相似文献
3.
本文对2012年秋季中国东海31个站位的海水样品中溶解态氨基酸（THAA）和颗粒态氨基酸（PAA）的分布与组成进行了研究。结果表明：表层海水中溶解游离氨基酸(DFAA)的平均浓度为0.12±0.04 μmol/L (0.06~0.19 μmol/L),溶解结合氨基酸(DCAA)的平均浓度为0.61±0.51 μmol/L (0.15~1.79 μmol/L),PAA的平均浓度为0.11±0.06 μmol/L (0.02~0.27 μmol/L)。THAA的水平分布特点大致为近岸高、远岸低;PAA的水平分布特点是近岸海域向远海海域分布呈现逐渐减小的趋势。THAA的垂直分布特点是由表层向底层逐渐降低。DCAA、PAA与Chl-a有很好的相关性,而DFAA与Chl-a的相关性不明显。东海表层海水中THAA的主要组分是天门冬氨酸、谷氨酸、丝氨酸、甘氨酸、苏氨酸及丙氨酸,PAA的主要组分是天门冬氨酸、谷氨酸、丝氨酸、甘氨酸、丙氨酸及亮氨酸。在表层海水中氨基酸是作为一个整体而对海洋生物地球化学过程产生影响的。 相似文献
4.
2021年3月对长江口及其邻近海域9个断面溶解氨基酸(THAA)、溶解有机碳(DOC)和溶解有机氮(DON)的分布和组成进行了调查研究。结果表明:THAA的浓度范围为1.24~4.71μmol/L,平均浓度为(2.61±0.85)μmol/L;DOC的浓度范围为118.17~450.58μmol/L,平均浓度为(149.73±33.34)μmol/L;DON的浓度范围为10.48~24.45μmol/L,平均浓度为(13.80±1.81)μmol/L。THAA、DOC和DON的水平分布表现出近岸高于远岸的特点,表明陆源输入对调查区域的THAA等分布有重要影响。而THAA与D-天门冬氨酸、D-谷氨酸、D-丝氨酸和D-丙氨酸的D/L比均呈显著负相关,与天门冬氨酸/β-丙氨酸(Asp/β-Ala)呈正相关,表明细菌活动是影响THAA浓度变化的重要因素。长江口及邻近海域的优势氨基酸为L型氨基酸,D型氨基酸和非蛋白型氨基酸的占比仅为7.34%。基于C/N比值分析,长江口及其邻近海域溶解有机物(DOM)的来源受到长江冲淡水和台湾暖流的共同影响。THAA-C%、THAA-N%、降解因子和反应活性指数表明:水平方向上盐度接近于0的淡水区域和盐度高于34的远海区域降解程度较高;垂直方向上随着深度的增加,有机物的降解程度逐渐升高。调查区域有机物的降解程度主要受到陆源输入和细菌活动的影响。 相似文献
5.
南海北部海水中氨基酸的分布及其对溶解有机物降解行为的指示研究 总被引：2，自引：0，他引：2
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。 相似文献
6.
于2010年5—6月搭乘日本KH10-1航次,对西北太平洋两个不同深度站位甲烷(CH4)和氧化亚氮(N2O)的垂直分布及海气交换通量进行了研究。结果显示:研究海域表层海水中CH4和N2O浓度分别为(2.55±0.22)nmol/L和(7.50±1.11)nmol/L,饱和度分别为126%和116%,均处于轻度过饱和状态。在垂直方向上,CH4浓度分布呈现次表层极大的特征,次表层以下CH4浓度随深度增加逐渐减小。CH4次表层极大值可能是由于细菌利用甲基化合物进行好氧产生和在悬浮颗粒物、浮游动物或其他海洋生物肠道内厌氧微环境产生的综合作用造成的。N2O浓度随深度的增加而增大,在跃层下部达到最大值,N2O与溶解氧的垂直分布呈镜像关系。水体中N2O主要通过硝化过程产生。利用LM86和W92公式计算得到CH4的海气交换通量分别为(0.76±0.57)μmol/(m2·d)和(1.57±0.67)μmol/(m2·d),N2O的海气交换通量分别为(1.96±0.24)μmol/(m2·d)和(3.08±0.38)μmol/(m2·d),因此西北太平洋是大气CH4和N2O的净源。 相似文献
7.
用高效液相色谱法对2010年9月南黄海33个站位表层海水中总水解氨基酸(THAA)、溶解游离氨基酸(DFAA)、溶解结合氨基酸(DCAA)的分布、组成以及它们与环境因子的相关性进行了研究。结果表明:THAA平均浓度为2.08μmol/L,DFAA平均浓度为0.39μmol/L,DCAA平均浓度为1.69μmol/L。THAA浓度的分布大致呈近岸高、远岸低的特点;DFAA分布的规律性较差,在东部海域(中心约在35°N,123°E)出现高值。相关性分析显示溶解氨基酸与叶绿素a(Chl-a)、溶解无机氮(DIN)、细菌丰度、温度和盐度之间均无显著相关性。THAA中含量较高的个体氨基酸为丝氨酸、甘氨酸、天门冬氨酸、谷氨酸和丙氨酸,总和占70.59%。DFAA、DCAA中的主要成分与THAA基本相同。THAA中个体氨基酸的组成以34°N为界分为南北2个海区呈现明显的区域性特点。 相似文献
8.
基于中国第30次南极科学考察在南极半岛(60°~63°S)近岸海域获取的调查资料,分析了该海域生物化学要素中溶解有机碳(DOC)、总氮(TN)和总磷(TP)分布特征并讨论地形和水团对其的影响。结果表明:2014年夏季南极半岛近岸海域水体DOC浓度变化范围为40.5~78.1μmol/L,平均浓度为66.3μmol/L;TN浓度变化范围为4.2~29.5μmol/L,平均浓度为14.9μmol/L;TP浓度变化范围为0.8~2.9μmol/L,平均浓度为2.0μmol/L。表层DOC呈现研究海域西北部D1断面和东南部D5断面浓度较高,中部DOC浓度较低;表层TN与TP浓度高值区出现在研究海域西部D1断面北部以及南部,中部和东部浓度较低;DOC,TN和TP浓度的垂直分布与海底地形和水团交汇密切相关,水团运动受阻于地形致使生物化学要素在垂直方向再分布。DOC,TN和TP空间分布反映了南极半岛近岸海域生物化学要素复杂的流通,将为合理开发和利用南极资源及环境影响评价提供科学依据。 相似文献
9.
于2011年5至6月在东海采集不同深度海水样品,研究了其中溶存氧化亚氮(N2O)的分布并估算其海-气交换通量。结果表明,春季东海表层海水中溶存N2O浓度范围为6.31~11.88 nmol/L,平均值为(9.13±1.45)nmol/L;底层海水中N2O浓度范围为7.53~39.75 nmol/L,平均值为(13.71±7.76)nmol/L。随着深度的增加,N2O浓度逐渐升高。温度是影响春季东海N2O分布的主要因素,N2O浓度与温度呈负相关关系。长江冲淡水和黑潮水是东海N2O的重要来源。东海表层海水中N2O的饱和度范围为92.5%~139.3%,平均值为118.5%±10.3%,绝大多数站位都处于过饱和状态,因此,春季东海是大气N2O的净源。利用LM86公式和W92公式求得东海的海-气交换通量分别为(4.96±6.12)μmol/(m2·d)和(10.25±17.18)μmol/(m2·d),初步估算出东海年释放N2O通量约为0.061~0.127 Tg/a,占全球海洋释放总量的2.0%,远高于其所占的面积比0.2%。 相似文献
10.
南极普里兹湾及其邻近海域溶解有机碳的分布 总被引：5，自引：0，他引：5
中国南极科学考察第16航次期间(1999年11月～2000年4月),在南极普里兹湾及邻近海域的不同站位与水深采集海水样品用于溶解有机碳测定,通过高温催化氧化法完成样品的分析.结果表明,在调查期间,南极普里兹湾及其邻近海域各测站上层水体(0～100m)溶解有机碳浓度的变化范围为14.3～181.1μmol/dm3,平均为52.5μmol/dm3,该变化幅度比Ross海、太平洋等海域的相应值略大.溶解有机碳垂直分布的特征是0大于25大于50大于100m,即随深度的增加溶解有机碳浓度逐渐减小,与生物活动在垂直方向上的强弱变化相关.根据200m以深水柱溶解有机碳的垂直分布,可确定研究海域难降解溶解有机碳的浓度为40.4μmol/dm3,与其他研究所报道的数值(～42μmol/dm3)相近.上层水体(0～100m)过剩溶解有机碳的空间分布显示,64°S以北海域溶解有机碳过剩较多,而64°S以南海域则过剩溶解有机碳较少.溶解有机碳浓度与分布特征显示,普里兹湾及其邻近海域溶解有机碳浓度与南大洋其他海域相当,具有低溶解有机碳的一般特征.溶解有机碳浓度的空间分布呈现由西南向东北方向逐渐增加的趋势,这可能与南极陆架夏季上层水的北向扩展有关.生物活动及水体运动是研究海域溶解有机碳分布的主要影响因素. 相似文献
11.
《Deep Sea Research Part I: Oceanographic Research Papers》2001,48(3):811-832
Total hydrolysable amino acids (THAA), individual amino acid distributions, total organic carbon (TOC) and total nitrogen (TN) were measured in sediments across the Goban Spur continental slope at water depths of 651, 1296 and 3650 m. Objectives were to examine (1) differences in organic matter (OM) degradation state in surface sediments across the slope from sedimentary amino acid compositions, and (2) whether these differences are related to particle size distributions. Application of a ‘reaction–diffusion’ model to the sediment concentration profiles showed that TOC and THAA degradation rate constants decreased with increasing water depth. Ratios of degradation rate constants of THAA over TOC indicated that THAA turn over faster than TOC at 651 and 1296 m water depth only. From estimates of degradation rate constants of individual amino acids, it was concluded that with increasing water depth fewer amino acids contribute to overall THAA degradation. The contribution of THAA to TOC mineralisation decreased from the upper to the lower slope. Since at all three sampling stations the amino acids with the highest relative contribution to THAA had a higher abundance in sediments with reduced THAA mineralisation rates, we conclude that the overall amino acid reactivity decreases with increasing water column depth. A principal component analyses, carried out on normalised amino acid mole percentages, established significant shifts in amino acid compositions and confirmed that (1) OM degradation state increased from 651 to 3650 m and (2) that OM in the finest fraction at the shallowest station appeared to be considerably less degraded than in the coarser fractions or any size fractions at the deeper stations. Therefore, we conclude that downslope transport, sorting and accumulation of fine particles with continuous mineralisation of OM attached to the particles during vertical and lateral transport results in an increasing organic matter degradation state from the upper slope to the abyssal plain. 相似文献
12.
Distribution and alteration of amino acids in bulk DOM along a transect from bay to oceanic waters 总被引：2，自引：0，他引：2
A systematic survey of the concentrations and composition of total hydrolyzable amino acids (THAA) in bulk dissolved organic matter (DOM) was conducted at 11 stations along the 137°E transect from bay to oceanic areas in the northwestern Pacific. Concentrations of THAA and their contributions to dissolved organic carbon were high in the bay and coastal areas, declined toward the oceanic area and decreased with depth in the water columns. From the distribution patterns of the relative abundances of amino acids along the transect, individual amino acids were divided into four groups. One group included tyrosine, valine, isoleucine, phenylalanine, leucine and tryptophan, and was considered to represent easily degradable THAA, while glycine and alanine belonged to a more biorefractory group of THAA. Principal components analysis (PCA) was conducted to quantitatively differentiate patterns of amino acid composition. Amino acid groups based on PCA agreed with the groups classified by distribution patterns, indicating that first principal component scores reflected the degree of degradation of THAA in DOM, and were defined as a degradation index (DI). Two amino acids, glycine and alanine, increased in relative abundance with increasing DI, while valine, isoleucine, phenylalanine and leucine decreased with decreasing DI. The agreement indicated that the degradation process was the key factor controlling the quantity and quality of THAA in bulk DOM. 相似文献
13.
2015年12月在马里亚纳海沟"挑战者深渊"进行了定点样品采集,对温度、盐度、溶解氧、pH等环境参数进行了分析,讨论了营养盐的垂直分布特征、各形态营养盐结构特征及影响因素。研究发现,溶解氧在表层具有最大值,在1000 m左右出现极小值,而在8700 m深度具有较高溶解氧值(5.79 mg·L^-1),这可能与富氧水团的存在有关。硝酸盐表层含量较低,在1000和5367 m处出现双峰值。在表层水体中,溶解有机氮、磷是溶解总氮、溶解总磷的主要存在形式,表层以深,溶解无机氮、磷逐渐占据主导地位。磷酸盐表层含量最低,在1000 m处达到最大值,之后随着深度的增加浓度逐渐降低;硅酸盐在表层含量较低,在约4000 m处有最大值161.65μmol·L^-1,在4000 m以深,硅酸盐仍维持较高浓度。结果表明马里亚纳海沟"挑战者深渊"的溶解氧、pH及营养盐的垂直分布特征与大洋环流、海沟形态以及生物活动密切相关。 相似文献
14.
Jianming Pan Chuanyu Hu Jianfang Chen Xiaoya Liu Huaiyang Zhou Weidong Ji 《海洋学报(英文版)》2003,22(3):385-394
According to two cruises investigation information in summer and winter during 1998 and1999, the phosphorous concentration distribution and changes of summer and winter were discussed pri-marily in the South China Sea. The results show that the phosphate concentration of surface seawater insummer is distinctly lower than that in winter, averaging 0.04 μmol/dm3 in summer and 0.35 μmol/dm3 in winter. The organic phosphorous concentration of surface seawater in summer is higher than thatin winter, averaging 0.12μmol/dm3 in summer and 0.04 μmol/dm3 in winter respectively. The season-al changes of total phosphorus are similar to phosphate, averaging 0.22 μmol/dm3 in summer and 0.61μmol/dm3 in winter respectively. In vertical direction, phosphate, TDP and TP content are the lowestin upper 50 m water column, and increase in linearity rapidly with water depth, increasing slowly under500 m, reach to maximum about 1 000 m, then decrease slightly with water depth increasing. The ver-tical distribution is typical in summer, and there is small dispersed for phosphorus concentration for thesame depth of different stations. However, in winter there is a large disperse for phosphate, TDP andTP, specifically for phosphate at 200 m at which the concentration is maximum. This result indicatesthat there are large differences in hydrology and biology conditions that affect largely the chemical envi-ronment of the South China Sea. The organic phosphorus is the predominant in surface seawater of theSouth China Sea, but the inorganic phosphorus is the predominant in layers below depth of 150 m. Theorganic phosphorus concentration in deep water usually decreases with water depth increasing. The or-ganic phosphorus in summer is remarkably more than that in winter because of the strong biology activi-ties in summer. 相似文献
15.
南海海域海水中各形态磷的化学分布特征 总被引：6，自引：0，他引：6
根据1998年7月和1999年1月两个航次的调查资料,对南海水体中磷的含量分布以及夏、冬季变化规律进行了探讨.结果表明,南海表层水体中磷酸盐夏季含量明显低于冬季,夏季平均含量为0.004μmol/dm3,而冬季为0.35 μmol/dm3;有机磷含量夏季高于冬季,含量分别为0.12,0.04 μmol/dm3;总磷含量的季节变化与无机磷酸盐类似,夏、冬季含量分别为0.22,0.61 μmol/dm3.在垂向分布上表层50 m水柱中PO43--P,总溶解态磷和总磷含量最小,随水深增加基本上呈线性快速增加,至500 m增加减缓,1 000 m左右为最大含量,然后随着水深略有下降.在夏季垂直分布比较典型,不同站位在一水深的含量离散性小,而冬季PO43--P,总溶解态磷和总磷的垂直分布则显得离散性大,尤其是PO43--P分布在200 m左右出现最大值,说明当年冬季南海各区域存在着较大水文、生物差异,很大的影响了化学环境的变化.在南海表层水中通常以有机磷占优势,在150 m深处以下的水中则以无机磷为主.深水中溶解的有机磷含量一般随水深减少.夏季的有机磷明显高于冬季,表明夏季的生物作用强烈. 相似文献
16.
2018年7月对茅尾海主要入海河口区进行现场调查,分别采用二乙酰一肟法和分光光度法测定了表层海水中尿素和各种形态氮的浓度,分析了该海湾尿素的浓度变化、分布特征及溶解态氮的组成,并探讨其来源和分布的影响因素。结果表明:夏季茅尾海尿素的浓度(以N计)分布在0.40~1.13μmol/dm^3范围内,平均浓度为(0.51±0.18)μmol/dm^3。钦江入海口区尿素的平均浓度高于茅岭江入海口区,尿素占茅尾海溶解有机氮(DON)的0.8%~10.3%。茅尾海尿素分布特征主要表现为由河口向外海逐渐降低的特点,高值区主要位于河流入海口,陆源输入和海域自身生物地球化学过程是控制茅尾海尿素来源分布的主要影响因素。 相似文献
17.
Antoine Grémare Dimitri Gutiérrez Jean Michel Amouroux Gilles Vétion 《Progress in Oceanography》2005,65(1):89-111
Spatio-temporal changes in totally and enzymatically hydrolyzable amino acids (THAA and EHHA) and EHAA/THAA ratios of superficial sediments were assessed during 1997-1999 in three areas (i.e., the Gulf of Lions, the Bay of Biscay, and Central Chile) differing in their primary productivity. In all three areas, and even off Central Chile where a strong El Niño event took place during 1997-1998, spatial changes were always much greater than temporal ones. The factors affecting the spatial distributions of amino acid concentrations differed among areas. In the Gulf of Lions, sediment granulometry was apparently the most important driving force of THAA, EHAA, and EHAA/THAA, and there was no marked difference between stations located on the open slope and those in submarine canyons. Conversely, in the Bay of Biscay, there were clear differences between the stations located off Cap-Breton, on the open slope, and those in the Cap-Ferret canyon; the latter two featuring lower EHAA and THAA but higher EHAA/THAA. This pattern is likely to result from the predominance of different sources of organic matter and especially from the importance of continental inputs to the Cap-Breton canyon. Off Central Chile, amino acid concentrations and ratios were both maximal around 100 m depth, probably reflecting the interaction between the primary productivity gradient and the presence of an oxygen minimum zone (OMZ) reducing the degradation of sedimentary organics. When comparing the average values collected in the three areas studied, THAA and EHAA were highest in Central Chile, intermediate in the Bay of Biscay and lowest in the Gulf of Lions. EHAA/THAA ratios were also highest in Central Chile but were lowest in the Bay of Biscay. Differences between the Gulf of Lions and the Bay of Biscay could have been affected by sampling design. In Central Chile, the use of labile organic carbon to total organic carbon (C-LOM/TOC) and EHAA/THAA as indices of organic matter lability led to very similar results. This was not the case in the Bay of Biscay. It is therefore argued that the use of C-LOM/TOC should be restricted to highly productive areas. 相似文献
18.
Six sediment cores collected from various water depths and sampling locations along the western margin of the Bay of Bengal (BOB) were investigated for the total hydrolysable amino acids (THAA) and d-amino acids (d-AA) to understand their distribution, digenetic alteration and bacterial contribution to organic matter (OM). Irrespective of their location, THAA concentrations and yields generally decreased and mol% glycine increased with increasing water depth indicating that OM was degraded during its transit through the water column. Amino acid based degradation index (DI) indicated that OM of the surface sediments of shallow stations, BOB-1 to BOB-3 was relatively fresher than that of deeper stations, BOB-4, BOB-5 and BOB-6. The concentrations and mol% of the d-AA varied from 0.04 to 0.76 µmol gdw−1 and 0.3 to 8.5 mol%, respectively. Contribution of bacterial peptidoglycan amino acids to THAA (% THAApep/THAA) ranged between 4.0% and 55.0%. Both % THAApep/THAA and mol% d-AAs were significantly (p<0.01) higher in the surface sediments and decreased with sediment core depth. Based on the d-AA yields, bacterial OM accounted for 1.5–15.6% of TOC, and 3.7–50.0% of TN of the sediments of BOB. 相似文献