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1.
双台子河口水体有机碳分布特征研究 总被引：1，自引：0，他引：1
于2011年5月和8月通过研究双台子河口水体溶解有机碳(DOC)、颗粒有机碳(POC)和化学耗氧量(COD)的分布特征,阐述双台子河口水体有机碳的河口过程及其影响因素,并探讨总有机碳(TOC)和COD表征河口有机污染的区域性和季节性特征。研究表明:2011年5月双台子河口DOC、POC和COD含量范围分别为4.04~5.06mg/L(平均4.60mg/L)、2.93~10.85mg/L(平均7.01mg/L)和5.65~14.07mg/L(平均9.04mg/L);8月分别为10.87~46.04mg/L(平均26.75mg/L)、0.88~17.27mg/L(平均4.16mg/L)和2.42~67.62mg/L(平均17.85mg/L)。DOC、POC和COD的含量由河到海总体呈现逐渐降低的趋势,双台子河口不同区段DOC、POC和COD的时空分布,及其主要和次要影响因素具有一定的差别。有机碳来源和海水的稀释作用是影响双台子河口有机碳分布的主要因素,现场生物生产和悬浮颗粒物影响较小。双台子河口水体中TOC和COD呈现线性不显著正相关关系,二者关系的季节差异显著。 相似文献
2.
黄河干流有机碳的时空分布特征 总被引：4，自引：0，他引：4
通过2003-2009年多个航次对黄河干流DOC(溶解有机碳)和POC(颗粒有机碳))及相关参数的调查研究,结果表明:TSS(颗粒悬浮物)为91.42～8188 mg/L,POC为0.65～24.20 mg/L,POC%(POC/TSS×100%)为0.44%～2.21%,DOC为1.57～4.77 mg/L,有机碳沿程分布具有明显的空间特征.花园口水文年调查中有机碳含量与流量的季节变化密切相关.POC主要受冲刷影响,而DOC在不同季节分别体现出冲刷、稀释或浓缩效应.修建水库和调水调沙这2个显著的人为干扰活动对黄河有机碳的性质及输运产生了截然不同的影响:库区自生源对有机碳的贡献明显大于干流,DOC/POC为6.64～12.00,DOC是有机碳的主要形式,同时水库截流,颗粒物沉降降低了颗粒有机碳的输运量,而调水调沙却加强了有机碳的输运,该时期DOC/POC为0.01～0.47,POC是有机碳输运的主导形态. 相似文献
3.
2012年长江口水域溶解有机碳分布特征及其与环境因子的关系 总被引：1，自引：0，他引：1
根据2012年2、5、8和11月长江口4个季节航次综合调查资料,分析了长江口及其邻近海域溶解有机碳(DOC)时空分布特征,探讨了DOC分布与盐度、表观耗氧量(AOU)、化学耗氧量(COD)、叶绿素a以及颗粒有机碳(POC)间的关系。结果表明,2012年长江口区DOC的浓度范围在0.53~5.21mg/L之间,均值为1.86mg/L。DOC浓度秋季最高,夏季和冬季次之,春季最低。DOC空间分布整体呈现近岸高、远岸低的格局,高值区分布在口门内和近岸水域,外海区DOC浓度随着离岸距离的增加而逐渐降低。各季节DOC空间分布略有差异。DOC与盐度、COD以及POC的相关关系较强,与AOU和叶绿素a相关性较弱。2012年长江口有机碳以DOC为主,DOC对总有机碳(TOC)的平均贡献率为55.8%,其中冬季贡献最大(59.4%),其次为秋季(59.2%)和春季(55.3%),夏季贡献率最低(49.4%)。 相似文献
4.
南沙渚碧礁生态系有机碳的分布及周日变化特征 总被引：4，自引：0，他引：4
1999 年 4 月对我国南沙群岛渚碧礁海水中溶解有机碳的分布及礁坪区颗粒有机碳 (POC) 和溶解有机碳 (DOC) 的周日变化特征进行了观测。结果表明,渚碧礁表层海水 DOC 变化范围为 1.43~3.62 mg/L,平均为 2.16 mg/L,含量分布大致表现为礁坪区>潟湖>礁外。潟湖 DOC 的垂直分布大致表现为表层高于底层,可能与表层浮游植物的光合作用有关。礁坪区 POC 及 DOC 都呈现显著的周日变化特征,POC 呈现夜晚高,白天低的特点,浮游植物的昼夜垂直移动可能是产生该现象的主要原因。DOC 的周日变化则主要受浮游动物昼夜垂直移动及细菌等生物活动的影响。 相似文献
5.
2006年12月在海南省东北部河流万泉河和文昌河以及周边的红树林和珊瑚礁体系采集水样,测定其溶解有机碳(DOC)和颗粒有机碳(POC)的含量.结果表明,万泉河水体中DOC和POC的平均浓度分别为139.3和39.7μmol·L-1;文昌河水体中DOC和POC的平均浓度则为133.0和47.4μmol·L-1,其周边红树林水体DOC和POC的平均浓度分别为214.1和27.9μmol·L-1;珊瑚礁周边水体DOC和POC的平均浓度分别为66.3和22.41μmol·L-1.文昌河周边的养殖活动及红树林水体对该河流中的高DOC和POC可能有显著贡献,且文昌河POC%与TSM浓度均呈显著负相关(R2=0.71,n=9).万泉河、文昌河和珊瑚礁周边水体POC/Chl a的比值分别介于72-312、43-196、122.5-334.估算浮游植物对万泉河、文昌河和珊瑚礁周边水体POC的贡献量分别为34%、45%、38%. 相似文献
6.
2006-04,2008-04,2008-05沿长江干流采集表层水样,并于2006-05～2007-05在下游大通站进行每月2次、为期1 a的连续观测,测定溶解有机碳(DOC)、颗粒有机碳(POC)及总悬浮物(TSM).结果表明:长江重庆以上江段DOC浓度较低,重庆至河口由于人为污染排放DOC表现出高值;干流POC与TSM显著正先关,POC%(TSM)随TSM含量增大呈负指数关系下降.大通站有机碳浓度及通量均表现出明显的季节性,2006-06～2007-05全年经大通站进入河口的DOC、POC通量分别为1.17×106tC和1.88×106tC,其中洪季(5～10月)输运的有机碳占到总有机碳的70%,组成以颗粒态为主.三峡水库135 m及156 m蓄水后,泥沙在库区的沉降作用显著影响长江POC的输运特征及入海通量;从目前观测结果看,三峡库区DOC浓度并没有表现出明显的升高趋势,可能与水库运行时间尚短有关. 相似文献
7.
《海洋湖沼通报》2016,(2)
利用海水池塘陆基实验围隔,研究了三疣梭子蟹(Portunus trituberculatus)、凡纳滨对虾(Litopenaeus vannamei)和菲律宾蛤仔(Ruditapes philippinarum)不同混养系统有机碳库储量,分别为蟹-虾混养(CS)、蟹-贝(CB)、虾-贝混养(SB)和蟹-虾-贝(CSB)混养系统,以蟹单养(C)系统作为对照。结果表明:(1)养殖期间各处理水体POC和DOC均值的变化范围分别为2.35~2.91mg C/L和8.82~10.89mg C/L。其中,POC以SB最高,CS次之,CB、CSB和C则显著小于处理SB(P0.05);水体DOC含量以CSB最高,单养系统C最低,但各处理间无显著差异(P0.05)。养殖期间各处理浮游植物有机碳均值变化范围为0.41~0.87mg C/L,其中以处理CSB最高,显著高于其它处理(P0.05),而单养系统C则为最低;各处理浮游动物有机碳均值变化范围为33.43~67.92μgC/L,以单养系统C浮游动物生物量最高,CS次之,均显著高于CB、SB和CSB(P0.05);养殖期间各处理细菌有机碳均值变化范围在0.33~0.61mg C/L之间,以CSB最高,显著高于C、CB和SB(P0.05),而与处理CS无显著差异(P0.05)。(2)实验期间,各处理有机碳组分贡献率为DOC腐质颗粒有机碳浮游植物有机碳浮游细菌有机碳浮游动物有机碳。总体而言,所有处理中CSB中浮游植物有机碳、浮游细菌有机碳以及水体DOC对TOC的贡献均相对高于其它处理,而浮游动物有机碳和腐质颗粒有机碳则相对较低;蟹单养系统C则相反,其浮游动物有机碳和腐质颗粒有机碳对水体TOC的贡献相对较大,而浮游植物有机碳、浮游细菌有机碳和DOC对水体TOC的贡献率相对其它处理均较小。 相似文献
8.
春季东海北部近岸水体中的溶解无机碳和有机碳的分布特征及其影响因素 总被引：1，自引：0，他引：1
根据2010年4月在东海北部近岸的调查,分析了研究海域溶解无机碳（DIC）和溶解有机碳（DOC）的含量及其分布状况,并分别对DIC、DOC与温度、盐度、表观耗氧量等要素的关系进行了初步探讨。结果表明,春季研究海域表、底层DIC平均含量分别为24．54mg／L和25．03mg／L,平面分布趋势均为近岸高于远岸,象山口附近... 相似文献
9.
对虾养殖围隔生态系细菌的生物量 总被引：1，自引：0，他引：1
对5个对虾养殖围隔生态系细菌生物量(以C计,下同)的研究结果表明,浮游细菌总生物量波动在0.09～0．83mg/dm3之间,平均0．37±0．21mg／dm3,占水层颗粒有机碳含量的11．94%;附着细菌生物量在(0．14～3．69)x10－2mg/dm3)之间,平均(0．77±0．58)x10-2mg/dm3,占浮游细菌总生物量的2.08%±1．95%。随着养殖时间的推移,浮游细菌总生物量、附着细菌生物量均有所上升。底泥细菌生物量为(44～132)x(10-6m/m),平均(86±23)x(10-6m/m),占底泥有机碳含量的1．55%。 相似文献
10.
采用实验测定和误差分析的方法, 对燃烧氧化-非分散红外吸收总有机碳分析仪vario TOC cube测定海水DOC 含量的不确定度进行了分析, 对导致测定结果不确定度的各分量进行了量化估算。结果表明, 其测定结果的不确定度主要来源于四个方面, 即样品重复性测量、标准曲线拟合、标准溶液配制(包括称量、定容、移液产生的不确定度, 标准物质纯度和相对原子质量产生的不确定度)及测量仪器本身, 相对标准不确定度分量分别为0.016、0.018、0.0086、0.0079。标准曲线拟合与样品重复性测量是影响海水DOC 测定不确定度的主要因素, 但标准溶液配制和测量仪器所引起的不确定度亦不可忽略。对实际海水DOC 浓度为1.20 mg/L 的样品分析,合成以上四种不确定度分量得到DOC 测定结果的标准不确定度为0.21 mg/L。按照正态分布,取扩展因子k=2, 则扩展不确定度为0.07 mg/L, 此海水样品中DOC 含量的测定结果应为(1.20±0.07) mg/L(k= 2)。 相似文献
11.
报道一种合成２,２－二甲基－４－戊烯酸的新方法。由异丁醛与烯丙醇缩合得到２,２－二甲基－４－戊烯醛,后者经氧化银选择氧化生成２,２－二甲基－４－戊烯酸。此法氧化产率（９６％）高于分子氧氧化法（６１％）和歧化法（４１％）。反应中析出的金属银能定量回收,循环使用。 相似文献
12.
13.
海水中溶解有机碳（DOC）的测定 总被引：18，自引：0，他引：18
本文论述了海水中溶解有机碳(DOC)的测定方法,对DOC的测定原理及氧化方法进行了讨论,并提出了妨碍海水中DOC测定准确度提高的因素,这对于建立高准确度和精密度的新分析方法具有重要的意义。 相似文献
14.
长江口盐度梯度下不同形态碳的分布、来源与混合行为 总被引：1，自引：0，他引：1
河口碳的生物地球化学过程是全球碳循环的重要组成。通过测定溶解无机碳（DIC）及其稳定同位素丰度（δ13CDIC），溶解有机碳（DOC），有色溶解有机物（CDOM），颗粒有机碳（POC）及其稳定同位素丰度（δ13CPOC）与元素比值（N/C）及相关指标，研究了2014年7月长江口盐度梯度下不同形态碳的分布、来源和混合行为。结果表明，DIC浓度、DOC浓度、POC含量分别为1 583.2~1 739.6 μmol/L，128.4~369.4 μmol/L和51.2~530.8 μmol/L，这些不同形态碳及CDOM的荧光组分的分布模式相似，均是从口内到口外，整体呈现先增大后减小的趋势，并与盐度呈现非保守混合行为。添加作用主要发生在在口门处最大浑浊带附近。与含量相反，从口内到口外，δ13CDIC和δ13CPOC均呈现逐渐减小再增大的趋势，在口门附近达到最低值，分别为-9.7‰和-26.7‰。在口门附近不同形态碳含量上升及δ13CDIC、δ13CPOC的降低可能主要与沉积物再悬浮及微生物作用有关。基于蒙特卡洛模拟的三端元混合模型的结果显示，河口内外POC来源变化明显，口内POC以陆源有机碳贡献为主，平均为62.3%，口外海源贡献逐渐增加。CDOM相关参数结果表明长江口CDOM主要来自陆源输入，海源及人类活动等也对其产生影响。 相似文献
15.
Final dissolved organic carbon broad community intercalibration and preliminary use of DOC reference materials 总被引：1，自引：0，他引：1
Jonathan H. Sharp Craig A. Carlson Edward T. Peltzer Dawn M. Castle-Ward Karen B. Savidge Katherine R. Rinker 《Marine Chemistry》2002,77(4):1819
A broad community intercalibration exercise for accurate measurement of dissolved organic carbon (DOC) in seawater has been carried out over a period of 5 years. A set of 10 natural samples with DOC content from 40 to 200 μM C were accompanied by two glucose standards and a “zero C” blank; all sealed in glass ampoules. Samples were sent to all interested analysts for “blind” analysis; 62 laboratories in 17 countries participated. A total of 59 separate analyses were determined to be acceptable by screening criteria based on standards and blank; another nine sets of analyses did not pass the screening. The majority of the analyses, both those passing and those that did not, were performed with high temperature combustion (HTC) methods, six sets of analyses were done using wet chemical oxidation methods.From the 53 sets of acceptable HTC analyses, the coefficient of variation (%CV) for analytical comparability of the samples was 10% (“community precision”). It is estimated that the individual replicate injection precision for most instruments was approximately 2% and that no additional variability was caused by differences within the ampoules of individual samples. The additional variability over 2% was likely a result of both random and systematic differences in analytical capabilities from instrument to instrument and from day to day for individual instruments. With an arbitrary selection after the fact, smaller subsets of analysts can show comparability better than 10% and duplicate or triplicate runs on different days of the full sets of samples in several laboratories showed comparability in the 2–6.5% range. Experienced oceanic analysts, with internal or shared reference materials, can now show reproducibility and comparability at a level closer to 2%.Preliminary use of DOC reference materials by 14 participants showed day-to-day reproducibilities for their laboratories in the 2–6% range in most cases; several with poorer reproducibility do not normally perform DOC analyses on samples with concentrations as low as the deep ocean reference used here. Use of these reference materials can also give a demonstration of comparability between laboratories. For credibility of DOC analyses, it is necessary for analysts to use community reference materials and report results of their analytical performance with these references.This paper does not identify individual data nor should it be considered an evaluation of individual laboratories or analysts. The purpose is to show the summary picture of the international community of DOC analysts as it existed in the mid- to late 1990s. 相似文献
16.
The distribution and chemical properties of chromophoric dissolved organic matter (CDOM) in the Jiaozhou Bay, China were examined during four cruises in 2010-2011. The influence of freshwater and industrial and municipal sewage along the eastern coast of the bay was clearly evident as CDOM levels (defined as a 305 ), and dissolved organic carbon (DOC) concentrations were well correlated with salinity during all the cruises. Moreover, DOC concentrations were significantly correlated with chlorophyll a concentrations in the surface microlayer as well as in the subsurface water. The concentrations of DOC and CDOM displayed a gradually decreasing trend from the northwestern and eastern coast to the central bay, and the values and gradients of their concentrations on the eastern coast were generally higher than those on the western coast. In addition, CDOM and DOC levels were generally higher in the surface microlayer than in the subsurface water. In comparison with DOC, CDOM exhibited a greater extent of enrichment in the microlayer in each cruise, with average enrichment factor (E F ) values of 1.38 and 1.84, respectively. Four fluorescent components were identified from the surface microlayer and subsurface water samples and could be distinguished as peak A, peak T, peak B and peak M. For all the cruises, peak A levels were higher in the surface microlayer than in the subsurface water. This pattern of variation might be attributed to the terrestrial input. 相似文献
17.
Relevance of peat draining rivers in central Sumatra for the riverine input of dissolved organic carbon into the ocean 总被引：1，自引：0，他引：1
Sources and discharges of dissolved organic carbon (DOC) from the central Sumatran river Siak were studied. DOC concentrations in the Siak ranged between 560 and 2594 μmol l−1 and peak out after its confluence with the river Mandau. The Mandau drains part of the central Sumatran peatlands and can be characterized as a typical blackwater river due to its high DOC concentration, its dark brown-coloured, acidic water (pH 4.4–4.7) and its low concentration of total suspended matter (12–41 mg l−1). The Mandau supplies about half of the DOC that enters the Siak Estuary where it mixes conservatively with ocean water. The DOC input from the Siak into the ocean was estimated to be 0.3 Tg C yr−1. Extrapolated to entire Indonesia the data suggest a total Indonesian DOC export of 21 Tg yr−1 representing 10% of the global riverine DOC input into the ocean. 相似文献
18.
Dissolved organic matter cycling in the confluence of the Atlantic and Indian oceans south of Africa
The boundary between the Atlantic and Indian sectors of the Southern Ocean is a key spot of the thermohaline circulation, where the following water masses mix up: Indian Central water (ICW), South Atlantic Central Water (SACW), Antarctic Intermediate Water (AAIW), Circumpolar Deep Water (CDW), North Atlantic Deep Water (NADW), Weddell Sea Deep Water (WSDW) and Antarctic Winter Water (WW). An optimum multiparameter analysis based on the distributions of potential temperature, salinity, NO (=O2+9.3×NO3) and silicate during the GoodHope 2004 (GH04) cruise allowed us to (i) define the realms of these water masses; (ii) obtain the water mass proportion weighted-average (archetypal) apparent oxygen utilization (AOU) and dissolved organic carbon (DOC) concentrations of each water mass; and (iii) estimate the contribution of DOC to the oxygen demand of the study area. WW represented only 5.2% of the water volume sampled during GH04, followed by WSDW with 10.8%, NADW with 12.7%, SACW with 15.3%, AAIW with 23.1% and CDW with 32.8%. The distributions of DOC and AOU were mainly explained by the mixing of archetypal concentrations of these variables, 75±5% and 65±3% respectively, which retained the variability due to the basin-scale mineralization from the formation area to the barycentre of each water mass along the GH04 line. DOC accounted for 26±2% and 12±5% of the oxygen demand of the meso- and bathypelagic ocean, respectively. Conversely, local mineralization processes, retained by the residuals of the archetypal concentrations of DOC and AOU, did not contribute to improve significantly the mixing model of DOC. 相似文献
19.
Dissolved Organic Matter in Oceanic Waters 总被引：13，自引：0，他引：13
The amount of information on oceanic dissolved organic matter (DOM) has increased dramatically in the last decade thanks to
the advances in chemical characterization. This information has supported the development of some novel and important ideas
for DOM dynamics in the ocean. Consequently, we have a better understanding of the importance of DOM in oceanic biogeochemical
cycles. Here we review studies published mainly during 1995–2001, synthesize them and discuss unsolved problems and future
challenges. The measurement, distribution and turnover of dissolved organic carbon (DOC) are presented as the bulk dynamics
of the oceanic DOM. The size spectrum, elemental composition, and chemical compositions at molecular and functional group
levels are described. The mechanisms proposed for the survival of biomolecules in DOM are discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
20.
南黄海溶解有机碳的生物地球化学特征分析 总被引：1，自引：5，他引：1
依据1997-2003年每年1次的南黄海调查得到的溶解有机碳(DOC)数据,重点分析了2002年秋末冬初季节南黄海DOC的分布特征及其生物地球化学控制机制。结果表明,2002年秋末冬初南黄海表层海水DOC质量浓度为1.62~2.42 mg/L,平均值为2.02 mg/L,高于大洋的平均值,具有典型近海特征;南黄海DOC分布呈现北部高,南部低,在量值上,A断面>B断面>C断面,且有显著近岸高、远离海岸中部海区低的特点。近岸高值区主要受陆源输入影响,包括径流输入和人类活动两个方面,陆源输入相对生物生产过程更为重要;中部低值区主要受控于来自东海低DOC海流的冲淡作用。垂直方向上DOC质量浓度变化不大,这明显与南黄海海水混合较好有关。7 a中南黄海DOC质量浓度总体上呈略微下降趋势,北部海域表现尤为明显,南黄海生物生产量的下降及近年来南黄海整体环境质量的提高是引起DOC下降的主要原因。 相似文献