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1.
春秋季南黄海二甲基硫(DMS)与二甲巯基丙酸(DMSP)的浓度分布研究 总被引：2，自引：0，他引：2
Temporal distributions of dimethylsulfide(DMS) and dimethylsulfoniopropionate(DMSP) were studied in the southern Yellow Sea(SYS) during April and September 2010. The mean concentrations(range) of DMS, dissolved and particulate DMSP(DMSPd and DMSPp) in the surface waters in spring are 1.69(0.48–4.92), 3.18(0.68–6.75)and 15.81(2.82–52.33) nmol/L, respectively, and those in autumn are 2.80(1.33–5.10), 5.45(2.19–11.30) and 30.63(6.24–137.87) nmol/L. On the whole, the distributions of DMS and DMSP in spring are completely different from those in autumn. In the central part of the SYS, the concentrations of DMS and DMSP in spring are obviously higher than those in autumn, but the opposite situation is found on the south of 34°N, which can be attributed to the differences in nutrients and phytoplankton biomass and composition between spring and autumn. Besides,the seasonal variations of water column stability and the Changjiang diluted water also have significant impact on the distributions of DMS and DMSP in spring and autumn on the south of 34°N. DMS and DMSPp concentrations coincide well with chlorophyll a(Chl a) levels in the spring cruise, suggesting that phytoplankton biomass may play an important role in controlling the distributions of DMS and DMSPp in the study area. Annual DMS emission rates range from 0.015 to 0.033 Tg/a(calculated by S), respectively, using the equations of Liss and Merlivat(1986) and Wanninkhof(1992). This result implies a significant relative contribution of the SYS to the global oceanic DMS fluxes. 相似文献
2.
A chemoreduction-purge-and-trap gas chromatographic method has been developed for the determination of trace dimethylsulfoxide (DMSO) in seawater. In the analysis procedure, DMSO was first reduced to dimethylsufide (DMS) by sodium borohydride and then the produced DMS was analyzed using the purge-and-trap technique coupled with gas chromatographic separation and flame photometric detection. Under the optimum conditions, 97% DMSO was reduced in the standard solution samples with a standard deviation of 5% (n=5). The detection limit of DMSO was 2.7 pmol of sulfur, corresponding to a concentration of 0.75 nmol/L for a 40 ml sample. This method was applied to determine the dissolved DMSO (DMSOd) and particulate DMSO (DMSOp) concentrations in the surface seawater of the Jiaozhou Bay, and the results showed that the DMSOd and DMSOp concentrations varied from 16.8 to 921.1 nmol/L (mean:165.2 nmol/L) and from 8.0 to 162.4 nmol/L (mean:57.7 nmol/L), respectively. The high concentrations of DMSOp were generally found in productive regions. Consequently, a significant correlation was found between the concentrations of DMSOp and chlorophyll a, suggesting that phytoplankton biomass might play an important role in controlling the distribution of DMSOp in the bay. Moreover, in the study area, the concentrations of DMSOd were significantly correlated with the levels of DMS, implying that the production of DMSOd is mainly via photochemical and biological oxidation of DMS. 相似文献
3.
春、秋季南黄海浮游纤毛虫丰度及生物量的分布差异 总被引：1，自引：0，他引：1
Seasonal variation of marine plankton spatial distribution is important in understanding the biological processes in the ocean.In this study,we studied spatial distribution of planktonic ciliate abundance and biomass in the central deep area(station depth greater than 60 m) and the coastal shallow area(station depth less than 60 m) of the southern Yellow Sea(32°–36.5°N,121°–125°E) in spring(April) and autumn(October–November) of 2006.Our results showed that both ciliate abundance and biomass in the surface waters were higher in spring((1 490±2 336)ind./L;(4.11±7.81) μg/L) than in autumn((972±823) ind./L;(1.11±1.18) μg/L,calculated by carbon).Ciliate abundance and biomass in the surface waters of the coastal shallow area were similar in spring and autumn.However,in the central deep area,those values were much higher in spring((1 878±2 893) ind./L;(5.99±10.10)μg/L) than in autumn((738±373) ind./L;(0.74±0.76) μg/L).High values of ciliate abundance and biomass occurred in the central deep area in spring and in the coastal shallow area in autumn.Mixotrophic ciliate Laboea strobila was abundant in the central deep area in spring,when a phytoplankton bloom occurred.However,in autumn,L.strobila was abundant in the coastal shallow area.Boreal tintinnid Ptychocyli obtusa was found in spring.Both L.strobila and P.obtusa were concentrated in the surface waters when their abundance was more than 1 000 ind./L.Peaks of these species were in the subsurface waters when their abundance was less than 400 ind./L.This study showed that both high abundance and biomass of ciliates occurred in different areas in southern Yellow Sea seasonally. 相似文献
4.
The southern Changjiang River Estuary has attracted considerable attention from marine scientists because it is a highly biologically active area and is biogeochemically significant.Moreover,land-ocean interactions strongly impact the estuary,and harmful algal blooms(HABs) frequently occur in the area.In October 2010 and May 2011,water samples of chromophoric dissolved organic matter(CDOM) were collected from the southern Changjiang River Estuary.Parallel factor analysis(PARAFAC) was used to assess the samples' CDOM composition using excitation-emission matrix(EEM) spectroscopy.Four components were identified:three were humic-like(C1,C2 and C3) and one was protein-like(C4).Analysis based on spatial and seasonal distributions,as well as relationships with salinity,Chl a and apparent oxygen utilization(AOU),revealed that terrestrial inputs had the most significant effect on the three humic-like Components C1,C2 and C3 in autumn.In spring,microbial processes and phytoplankton blooms were also important factors that impacted the three components.The protein-like Component C4 had autochthonous and allochthonous origins and likely represented a biologically labile component.CDOM in the southern Changjiang River Estuary was mostly affected by terrestrial inputs.Microbial processes and phytoplankton blooms were also important sources of CDOM,especially in spring.The fluorescence intensities of the four components were significantly higher in spring than in autumn.On average,C1,C2,C3,C4 and the total fluorescence intensity(TFI) in the surface,middle and bottom layers increased by123%–242%,105%–195%,167%–665%,483%–567% and 184%–245% in spring than in autumn,respectively.This finding corresponded with a Chl a concentration that was 16–20 times higher in spring than in autumn and an AOU that was two to four times lower in spring than in autumn.The humification index(HIX) was lower in spring that in autumn,and the fluorescence index(FI) was higher in spring than in autumn.This result indicated that the CDOM was labile and the biological activity was intense in spring. 相似文献
5.
Temporal and spatial distribution of biogenic (BSi) and lithogenic (LSi) silica were studied in the Changjiang (Yangtze River) Estuary and its adjacent area. The annual average BSi and LSi concentrations were (1.71 ± 1.79) μmol/L and (0.56 ± 1.41) mmol/L, respectively. Both BSi and LSi were high in the inshore areas, where they received terrigenous discharge from the Changjiang, and decreased towards the offshore region. BSi and LSi were most abundant at the near bottom layer due to the high sedimentation rates and resuspension of sediment. Diatom blooms occurred in summer with high Chl a concentration in the surface layer, which induced that BSi in the surface layer during summer was obviously higher than that in the surface layer of other seasons. LSi concentration was maximal in autumn and spring and minimum in summer, associated with the seasonal variation of SPM values. Drifting investigation and mesocosm experiments were conducted during dinoflagellate bloom, aiming to understand the effect of nutrients on BSi by changing the phytoplankton composition. The results show that the low dissolved inorganic phosphorus concentration and high molar ratio of N/P (dissolved inorganic nitrogen vs. dissolved inorganic phosphorus), were the important factors for decreasing diatom biomass in the study area, and it would subsequently decrease the BSi concentration in aquatic ecosystem. 相似文献
6.
Phytoplankton growth rates and mortality rates were experimentally examined at 21 stations during the 2017 spring intermonsoon(April to early May) in the northern and central South China Sea(SCS) using the dilution technique, with emphasis on a comparison between the northern and central SCS areas which had different environmental factors. There had been higher temperature but lower nutrients and chlorophyll a concentrations in the central SCS than those in the northern SCS. The mean rates of phytoplankton growth(μ_0) and microzooplankton grazing(m) were(0.88±0.33) d~(–1) and(0.55±0.22) d~(–1) in the central SCS, and both higher than those in the northern SCS with the values of μ_0((0.81±0.16) d~(–1)) and m((0.30±0.09) d~(–1)), respectively.Phytoplankton growth and microzooplankton grazing rates were significantly coupled in both areas. The microzooplankton grazing impact(m/μ_0) on phytoplankton was also higher in the central SCS(0.63±0.12) than that in the northern SCS(0.37±0.06). The microzooplankton abundance was significantly correlated with temperature in the surface. Temperature might more effectively promote the microzooplankton grazing rate than phytoplankton growth rate, which might contribute to higher m and m/μ_0 in the central SCS. Compared with temperature, nutrients mainly affected the growth rate of phytoplankton. In the nutrient enrichment treatment,the phytoplankton growth rate(μn) was higher than μ_0 in the central SCS, suggesting phytoplankton growth in the central SCS was nutrient limited. The ratio of μ_0/μn was significantly correlated with nutrients concentrations in the both areas, indicating the limitation of nutrients was related to the concentrations of background nutrients in the study stations. 相似文献
7.
ZHENG Wei LI Fen SHI Honghu HUO Yuanzi LI Yan CHI Yuan GUO Zhen WANG Yuanyuan SHEN Chengcheng LIU Jian QIAO Mingyang 《海洋学报(英文版)》2016,35(2):46-55
To study the water quality influenced by the anthropogenic activities and its impact on the phytoplankton diversity in the surface waters of Miaodao Archipelago, the spatiotemporal variations in phytoplankton communities and the environmental properties of the surface waters surrounding the Five Southern Islands of Miaodao Archipelago were investigated, based on seasonal field survey conducted from November 2012 to August 2013. During the survey, a total of 109 phytoplankton species from 3 groups were identified in the southern waters of Miaodao Archipelago, of which 77 were diatoms, 29 were dinoflagellates, and 3 were chrysophytes. Species number was higher in winter (73), moderate in autumn (70), but lower in summer (31) and spring (27). The species richness index in autumn (5.92) and winter (4.28) was higher than that in summer (2.83) and spring (1.41). The Shannon-Wiener diversity index was high in autumn (2.82), followed by winter (1.99) and summer (1.92), and low in spring (0.07). The species evenness index in autumn (0.46) and summer (0.39) was higher than that in winter (0.32) and spring (0.02). On the basis of principal component analysis (PCA) and redundancy analysis (RDA), we found that dissolved inorganic nitrogen (DIN) and chemical oxygen demand (COD) in spring, COD in summer, pH in autumn, and salinity and oil pollutant in winter, respectively, showed the strongest association with the distribution of phytoplankton diversity. The spatial heterogeneity of the southern waters of Miaodao Archipelago was quite obvious, and three zones, i.e., northeastern, southwestern and inter-island water area, were identified by cluster analysis (CA) based on key environmental variables. 相似文献
8.
Changes of nutrient concentrations and N: P: Si ratios and their possible impacts on the Huanghai Sea ecosystem 总被引：4，自引：1，他引：3
To investigate the impacts of nutrient concentrations and N:P:Si ratios on the ecosystem of the Huanghai Sea (Yellow Sea), the current status and long-term variation of nutrients concentrations and ratios as well as phytoplankton community structure in the Huanghai Sea were collected and analyzed. The results reveal great annual and seasonal fluctuations in the nutrient concentrations and N:P:Si ratios during 1998-2008 with no clear pattern observed in the whole region. Yet on a seasonal scale of spring and in the coastal regions such as the Jiaozhou Bay and Sanggou Bay, the increase of DIN concentration and N:P ratio as well as the decrease of phosphate and silicate concentrations and Si:N ratios were relatively significant. Many pelagic ecosystem changes have occurred concurrent with these changes of the nutrient regime, such as the recent increase of primary production, changes of phytoplankton chlorophyll a biomass and abundance, an increase of eutrophication, and occurrence of HABs. In addition, new trends in the variation of nutrients seem to be developing in some particular transect such as 36°N, which suggests that long-term and systematic ecosystem monitoring in the Huanghai Sea is necessary. 相似文献
9.
南黄海和中国东海中挥发性卤代烃的分布与海气通量 总被引：1，自引：0，他引：1
Distributions and sea-to-air fluxes of five kinds of volatile halocarbons(VHCs) were studied in the southern Yellow Sea(SYS) and the East China Sea(ECS) in November 2007. The results showed that the concentrations of 1,1,1-trichloroethane(C2H3Cl3), 1,1-dichloroethene(C2H2Cl2), 1,1,2-trichloroethene(C2HCl3), trichloromethane(CHCl3) and tetrachloromethane(CCl4) in the surface water were 0.31–4.81, 2.75–21.3, 1.21–17.1, 5.02–233 and 0.045–4.47 pmol/L, respectively, with the average values of 1.89, 12.20, 6.93, 60.90 and 0.33 pmol/L. On the whole, the horizontal distributions of C2H3Cl3, C2H2Cl2 and CCl4 were affected mainly by anthropogenic activities, while C2HCl3 and CHCl3 were influenced by biological factors as well as anthropogenic activities. In the study area, the concentrations of VHCs(except C2HCl3) exhibited a decreasing trend from inshore to offshore sites, with the higher values occurring in the coastal waters. The sea-to-air fluxes of C2H3Cl3, C2HCl3, CHCl3 and CCl4 were calculated to be-56.00–(-5.68),-7.31–123.42, 148.00–1 309.31 and-83.32–(-1.53) nmol/(m2·d), respectively, with the average values of-6.77, 17.14, 183.38 and-21.27 nmol/(m2·d). Our data showed that the SYS and ECS in autumn was a sink for C2H3Cl3 and CCl4, while it was a source for C2HCl3 and CHCl3 in the atmosphere. 相似文献
10.
Community structure of picoplankton abundance and biomass in the southern Huanghai Sea during the spring and autumn of 2006 总被引：2，自引：0，他引：2
During spring and autumn of 2006,the investigations on abundance,carbon biomass and distribution of picoplankton were carried out in the southern Huanghai Sea(Yellow Sea,sHS) . Three groups of picoplankton-Synechococcus(Syn) ,Picoeukaryotes(PEuk) and heterotrophic bacteria(BAC) were identified,but Prochlorococcus(Pro) was undetected. The average abundance of Syn and PEuk was lower in spring(5.0 and 1.3 × 10 3 cells/cm 3,respectively) than in autumn(92.4 and 2.7 × 10 3 cells/cm 3,respectively) ,but it was opposite for BAC(1.3 and 0.7 × 10 6 cells/cm 3 in spring and autumn,respectively) . And the total carbon biomass of picoplankton was higher in spring(37.23 ± 11.67) mg/m 3 than in autumn(21.29 ± 13.75) mg/m 3 . The ratios of the three cell abundance were 5:1:1 341 and 30:1:124 in spring and autumn,respectively. And the ratios of carbon biomass of them were 5:7:362 and 9:4:4 in spring and autumn,respectively. Seasonal distribution characteristics of Syn,PEuk,BAC were quite different from each other. In spring,Syn abundance decreased in turn in the central waters(where phytoplankton bloom in spring occurred) ,the southern waters and inshore waters of the Shandong Peninsula(where even Syn was undetected) ;the high values of PEuk abundance appeared in the central and southern waters and the inshore of the Shandong Peninsula;the abundance of BAC was nearly three order of magnitude higher than that of photosynthetic picoplankton,and high values appeared in the central waters. In autumn,Syn abundance in central waters was higher than that in surrounding waters,while for PEuk abundance,it decreased in turn in the inshore waters of the Shandong Peninsula,the southern waters and the central waters;BAC presented a complicated blocky type distribution. Sub-surface maximum of each group of picopalnkton appeared in both spring and autumn. Compared with the available literatures concerning the studied area,the range of Syn abundance was larger,and the abundance of BAC was higher. In addition,the conversion factors for calculating picoplanktonic carbon biomass were discussed,with the conversion factors which are different from previous studies in the same surveyed waters. The result of regression analysis showed that there was distinct positive correlation between BAC and photosynthetic picoplankton in spring(r=0.61,P 0.001) ,but no correlation was found in autumn. 相似文献
11.
秋季东海二甲基亚砜的分布与影响因素研究 总被引：1，自引：0，他引：1
2010年11月对东海进行了大面调查,研究了秋季东海表层水中颗粒态和溶解态二甲基亚砜(DMSOp和DMSOd)的水平分布和PN断面的垂直分布特征及其影响因素。结果显示,表层海水中DMSOp和DMSOd的浓度范围分别为2.49~85.5nmol/L和2.27~86.6nmol/L,平均值分别为(17.2±1.40)nmol/L和(15.3±1.29)nmol/L。DMSOp水平分布与叶绿素a(Chl a)相类似,呈现近岸高、远海低的趋势,而DMSOd浓度高值区主要集中在东海西南部上升流区域。分析PN断面的垂直分布可见,DMSOp在近岸底层水中浓度较高,而DMSOd浓度在表层出现高值。相关性分析的结果表明,DMSOp与颗粒态二甲巯基丙酸内盐(DMSPp)以及DMSOp/Chl a比值与盐度分别存在一定的相关性,说明DMSOp与DMSPp具有相似的来源及生理功能。此外,DMSOd与二甲基硫(DMS)浓度具有正相关关系,说明DMS的氧化是东海DMSOd的一个重要来源途径。 相似文献
12.
于2013年10~11月和2014年5~6月调查测定了东海陆架区海水中二甲亚砜(DMSO)的浓度,探讨了溶解态二甲亚砜(DMSOd)和颗粒态二甲亚砜(DMSOp)的水平和垂直分布、季节变化及其影响因素;此外,对沉积物间隙水中DMSOd的浓度以及表层海水中不同粒径的DMSOp和叶绿素a(Chl a)进行了分析。结果显示,秋季和夏初表层海水中DMSOd和DMSOp的平均浓度分别为(10.52±7.16)、(8.99±6.34)nmol·L^-1和(17.51±9.90)、(16.96±10.73)nmol·L^-1,存在明显的季节差异。秋季表层海水中DMSOp的高值区出现在Chl a较低的远岸海域,而夏初表层海水中DMSO的浓度从近岸到远海逐渐降低。间隙水中DMSOd的浓度明显高于底层海水中DMSOd的浓度,说明沉积物中存在DMSO的生产释放,可能是底层海水DMSO的重要来源。此外,粒径分布结果表明较大微型浮游植物(5~20μm)是秋季东海表层海水中DMSOp的主要贡献者。 相似文献
13.
黄、渤海二甲基硫化物的浓度分布与迁移转化速率研究 总被引：2，自引：1，他引：1
于2015年8-9月对黄、渤海海域进行现场调查，研究了海水中二甲基硫（DMS）、β-二甲巯基丙酸内盐（DMSP）、二甲亚砜（DMSO）的浓度分布、相互关系及影响因素，测定了DMS的生物生产与消耗、光化学氧化和海-气扩散速率，对DMS的迁移转化速率进行综合评价。结果表明:表层海水中DMS、溶解态DMSP（DMSPd）、颗粒态DMSP（DMSPp）、溶解态DMSO（DMSOd）和颗粒态DMSO（DMSOp）浓度的平均值分别为（6.12±3.01）nmol/L、（6.03±3.45）nmol/L、（19.47±9.15）nmol/L、（16.85±8.34）nmol/L和（14.37±7.47）nmol/L，整体呈现近岸高远海低，表层高底层低的趋势。DMS、DMSPd和DMSOp浓度与叶绿素（Chl a）浓度存在显著的相关性。表层海水中DMS光氧化速率顺序为:kUVA > kUVB > k可见，其中UVA波段占光氧化的70.8%。夏季黄、渤海微生物消耗、光氧化及海-气扩散对DMS去除的贡献率分别为32.4%、34.5%和33.1%，表明3种去除途径作用相当。黄、渤海DMS海-气通量变化范围为0.79~48.45 μmol/（m2·d），平均值为（11.87±11.35）μmol/（m2·d）。 相似文献
14.
2009—2011年东海陆架海域网采浮游植物群落的季节变化 总被引：3，自引：0，他引：3
根据2009年7、8月(夏季)、12月到翌年1月(冬季)、2010年11月(秋季)和2011年4、5月(春季)共4个航次在东海陆架区进行的现场多学科综合调查,报道了4个季节在整个东海海域的浮游植物的空间分布及群落结构特征,并探讨了影响其分布格局的环境因子效应。结果表明,东海浮游植物群落主要由硅藻、甲藻组成。共检出浮游植物5门88属299种(含未定种)。调查区夏季细胞丰度达最高,平均为(8 659.572±28 937.27)cell/L,其次是秋、冬季,春季最低,分别为(4 413.726±12 534.573)cell/L、(421.773±647.532)cell/L和(218.479±265.897)cell/L。硅藻细胞丰度在夏、秋、冬3个季节占总平均丰度的95%以上,甲藻细胞丰度在春季最高,占总浮游植物细胞丰度的69%。调查海区浮游植物丰度高值区主要集中在长江口海域,并向外海呈递减趋势。不同群落间存在季节更替和演替现象。物种丰富度自春夏秋冬逐渐升高。香农指数(Shannon-Wiener index)和均匀度指数(Pielou index)分布较为一致,物种丰富度指数(Margalef index)呈现时空分布差异。Pearson相关分析结果表明:不同季节的物种间更迭与海区特定的物理化学参数显著相关。 相似文献
15.
渤黄海营养盐结构及其潜在限制作用的时空分布 总被引：7，自引：0，他引：7
根据2006-2007年4个季节的现场调查资料,分析探讨了渤海和黄海营养盐结构分布变化特征及其对浮游植物生长的潜在的限制状况.结果表明,渤黄海水体 Si/N/P 比值均偏离 Redfield 比值,季节变化明显;春夏冬季 N/P和 Si/P比值由近岸向远岸海域递减,高值区主要分布在黄河口、鸭绿江口及苏北近岸,秋季上层水体N/P和Si/P比值的分布趋势有所不同,高值区主要分布在南黄海的中部海域.受陆源输入的影响,近岸特别是河口区 N/P和 Si/P比值均较高,温跃层的生消变化和生物活动调控着黄海中部海域营养盐结构的变化.渤黄海浮游植物生长主要受P的潜在限制,部分季节受N、Si的潜在限制;营养盐限制状况存在着明显的时空变化及不同营养盐的同时或交替限制的现象. 相似文献
16.
根据2006-07-2007-10对北黄海4个航次调查资料,分析并讨论了北黄海西部海区营养盐四季变化及其影响因素。DIN,PO4-P和SiO3-Si的浓度从春季到冬季逐渐升高。春、夏、秋季营养盐底层浓度均远远大于表层的,冬季营养盐各层浓度相近。黄海冷水团是影响北黄海西部营养盐季节变化的主要因素,黄海暖流和鸭绿江水的输入对北黄海西部营养盐季节变化影响不显著;受北黄海跃层的影响,北黄海西部海区营养盐浓度除冬季外,垂直方向均呈现出分层现象,表层浮游植物吸收营养盐,使表层营养盐浓度低于底层的。 相似文献
17.
黄、东海陆架海域温度垂直结构类型划分与温跃层分析 总被引：4，自引：0，他引：4
基于黄、东海陆架海域1997—1999年4个季节调查的CTD资料,采用拟阶梯函数逼近法对温度垂直剖面拟合逼近,然后按拟合均方差和跃层强度对黄、东海陆架区的温度垂直结构进行类型划分,共划分为6个类型:三层结构型(T型)、主跃层上位型(U型)、主跃层下位型(L型)、多阶梯状结构型(M型)、异常结构型(A型)和垂直均匀型(H型)。分析结果表明:温度垂直结构类型在黄海区域为:春季呈L型;夏季呈U型;秋季呈T型;冬季呈H型。东海北部春季基本呈T型;夏季西部呈T型,东部呈U型;秋、冬季演变为H型;东海南部春、夏季主要呈L型;秋、冬季除近岸出现逆温类型外,大部分区域呈H型。利用风和潮的混合卷挟模式阐述了各种温度垂直结构的形成机制,最后给出了黄、东海陆架海域的主温跃层特征值的区域分布和季节变化。 相似文献