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1.
海水中铁的测定方法 总被引：3，自引：0，他引：3
铁在地壳中的丰度为5.6% [1],但是在海水中的浓度却很低 ,特别是大洋中只有0.05～2nmol/L [2]。在整个海水体系的生物地球化学过程中 ,铁是一种举足轻重的元素。特别是对浮游植物 ,铁的重要性远远超过了其它微量元素 ,在植物的光合作用、电子呼吸链、氮的还原、叶绿素合成等方面有重要作用[3]。在类似南大洋[2]和赤道太平洋[4]的海域 ,同其中的主要营养盐 (氮、磷、硅 )的高浓度相比 ,其浮游植物的生物量却很低。近年来的研究表明这些区域的生物量是由铁限制的[5]。赤道太平洋海域(IronEX)[4]和极地南大洋(SORIREE)[6]的表层海水施铁实… 相似文献
2.
《中国海洋大学学报(自然科学版)》2015,(10)
于2012年8月利用现场调查结合现场培养的方法研究了南海南部海域异养浮游细菌的生物量、呼吸速率、比生长速率和生长效率对外源营养物的响应。结果表明,南海南部海域异养细菌生物量低于北部海域;外源营养物可显著影响南海南部异养细菌生物量、比生长速率和细菌呼吸速率。在海盆区域S1站,异养细菌生长主要受DOC和氮限制,同时添加DOC、氮和磷会使细菌生物量、比生长速率和细菌呼吸速率明显增加;而在近海陆架S2站主要受磷限制,DOC和磷的添加会极大地促进异养细菌生长。分析发现,外源营养物在促进异养细菌生长的也同时也提高了异养细菌的物质转换效率,使异养细菌的异养程度进一步加大。 相似文献
3.
采用浮游植物计数法、高效液相色谱串联质谱法、分光光度法等分析方法,探索了微小亚历山大藻(Alexandrium minutum)在批次培养过程中氮磷吸收、产毒、生物量、p H等参数的动态变化关系。结果表明,微小亚历山大藻对磷的吸收迅速,可以将磷储存于体内,待生长使用。该藻对氮的吸收相对缓慢,环境中氮缺乏时,产毒量不再增加,说明氮对产毒有着重要的调控作用。在第二对数期中出现了碳限制环境,导致叶绿素a在碳限制条件下无法表征藻的生物量,相反,叶绿素a和生物量呈负线性关系,可能是叶绿素转化成其它含碳物质,用于生长。毒素不仅存在于细胞体内,培养液中(胞外)也含有毒素,并且胞外毒素从稳定期开始逐渐升高。胞内毒素的组成中GTX1/4占据绝对优势,GTX2/3含量相对较少。生长延缓期和第一对数期,各种毒素组成比例相对稳定,而在随后的生长期内,GTX1/4在总毒素中的占比逐渐上升,GTX2/3占比逐渐下降,表明微小亚历山大藻毒素组成会随着生长周期的变化而发生变化。 相似文献
4.
《中国海洋大学学报(自然科学版)》2015,(5)
以胶州湾为研究区域,建立箱式生态动力学模型,模拟得到胶州湾浮游植物生长受营养盐限制情况的季节变化;通过数值实验分析了胶州湾营养盐限制的区域差异,并进一步比较了1960、1980年代及本世纪初营养盐限制情况的区别。结果表明,胶州湾内的营养盐限制作用有显著的季节变化。春季由于浮游植物旺发消耗大量营养盐,使得湾内营养盐限制春末最强;夏季是河流丰水季,营养盐补充充足,湾内营养盐限制最弱。从不同区域来看,养殖区全年表现为硅限制;河口区和湾口区夏季为磷限制,其他季节为硅限制。营养盐限制作用湾口区最强,养殖区次之,河口区最弱。受此影响,浮游植物生物量河口区最高,湾口区最低。从长期变化来看,1960年代,胶州湾内的营养盐限制作用以氮限制为主,1980年代呈硅和磷交替限制,逐渐演变到本世纪初的以硅限制为主,而且由于营养盐限制作用的逐渐增强,浮游植物生物量也呈现不断下降的趋势。 相似文献
5.
依据改革开放40 a来胶州湾营养盐状况历史资料以及2018—2019年的现场调查,对胶州湾营养盐历史变化过程及其生态效应进行了系统分析。结果表明:营养盐的浓度变化大致以2008年为分界节点,在2008年前胶州湾溶解无机氮(DIN)浓度呈现持续上升趋势,而溶解无机磷(DIP)、活性硅酸盐(DSi)浓度则先略有减少后快速增加;2008年后胶州湾3种营养盐浓度均快速减少。营养盐限制状况由20世纪80年代初期的氮限制、20世纪90年代的硅限制转变为目前的磷限制。胶州湾Chl a年均质量浓度一直在3μg·L^-1上下波动但近年来则呈下降趋势,浮游动物生物量1994年后大幅度增加。分析发现,入湾营养盐通量的增加和海域面积缩小是2008年前胶州湾营养盐浓度增加的主要原因,而近十几年来胶州湾环境综合整治措施的大力实施则是氮、磷营养盐浓度减少的主要原因。2010年以前贝类养殖是控制胶州湾浮游植物生物量的主要因素,但近年来溶解无机磷浓度的减少和浮游动物生物量的增加是Chl a质量浓度呈下降趋势的主要原因。 相似文献
6.
南黄海沉积物中氮、磷的生物地球化学行为 总被引：15，自引：4，他引：11
于2004年10月采集南黄海4个站位的柱状沉积物和29个站位的表层沉积物,用氧化浸取分光光度法研究了自然粒度下沉积物中的氮、磷分布特征以及控制其分布的生物地球化学机制。结果表明,多数站位随着沉积深度的增加,沉积物中氮、磷浓度趋于稳定。4个站稳定时氮浓度平均约为289μg/g,磷约为329μg/g,平均稳定浓度出现的沉积层次分别为氮>30cm,磷>22cm。氮、磷垂直分布形状的规则性与沉积速率密切相关,沉积速率越小的站位,其氮、磷垂直分布愈规则;海洋沉积物中的氮主要来源自海洋生物的代谢,而磷与陆源碎屑输入密切相关。氮与沉积物粘土含量、浮游动物生物量干重有明显的正相关关系。海水中浮游动物干重每增加1mg/m3,则沉积物中氮浓度增加5.64μmol/g,磷不存在这样的关系。沉积物中氮的早期成岩速率远高于磷,在沉积物海水界面附近氮约为磷的7.4倍。海水浮游生物生物量与沉积物中氮的早期成岩类型密切相关,在所研究的2004年秋季海水中,浮游动物生物量干重19mg/m3是沉积物中氮早期成岩类型转变的界限值,小于这一界限值,水体中的氮趋向于向沉积物中凝聚;大于19mg/m3,则沉积物中的氮趋向于向水体释放。 相似文献
7.
营养盐对中肋骨条藻和新月菱形藻生长及氮磷组成的影响 总被引：20，自引：4，他引：20
：于１９９５年５月１９９６年３月通过一次培养实验,研究了培养介质中营养盐含量变化对中肋骨条藻和新月菱形藻生长速率和藻体氮、磷含量的影响。根据Ｍｏｎｏｄ方程,磷酸盐影响中肋骨条藻和新月菱形藻生长速率的半饱和常数分别为０．５４μｍｏｌ／Ｌ和０．５０μｍｏｌ／Ｌ;硝酸盐影响两种藻生长速率的半饱和常数分别为４．０μｍｏｌ／Ｌ和１４．６μｍｏｌ／Ｌ,相比之下新月菱形藻更容易受到氮不足的限制。将Ｍｏｎｏｄ方程扩展得到营养限制复合模式,限制程度可用限制作用系数定量化表示,代表氮或磷。培养介质中营养盐浓度是限制浮游植物生长的决定因素,其Ｎ／Ｐ比值则反映ＮＯ_３－Ｎ和ＰＯ_４－Ｐ何者起主要限制作用。藻体氮、磷含量随和有明显变化。当＜０．８０时较低,磷含量因贮存而明显升高;当＜０．８０时藻体磷含量下降,氮含量略有增加。藻体氮含量或＞０．８０时基本上为非限制状态。 相似文献
8.
基于氮、磷收支的人工湿地-池塘循环水养殖系统净化效果评价 总被引：1，自引：0，他引：1
池塘循环水养殖与人工湿地相组合,是将养殖生产与净化养殖废水并举的新思路,研究该组合系统中氮、磷物质的源-汇作用,对系统工艺参数的设置具有指导意义。本文研究了在复合垂直潜流人工湿地-池塘循环水养殖系统中氮、磷生源要素的流向与收支,并通过氮、磷收支评价人工湿地对池塘尾水净化效果。研究表明:在5个月的试验周期内,饲料投入是该养殖系统氮、磷收入最主要的途径,分别占总收入的65.61%和81.44%,其次是水体中带入的氮、磷。在试验初期,由于养殖生物与湿地植物的生物量较小,因此其对系统的氮、磷收入部分贡献较小。沉积物蓄积是氮、磷最主要的支出途径,占总支出氮、磷的比例为28.60%和42.23%;其次为养殖生物的收获,占总支出氮、磷的26.05%和30.77%;人工湿地植物与基质蓄积的氮、磷占总支出的15.81%和16.11%;通过池塘底泥渗漏损失的氮、磷较少。人工湿地对氨氮、总氮、总磷的去除率分别为33.72%~66.32%、36.35%~72.40%、44.69%~57.32%,且氨氮与总氮的去除率受温度影响显著。研究结果表明:人工湿地对池塘尾水有显著的净化效果,可通过植物收割、基质移除等方式去除系统内未被有效利用的氮、磷,减少池塘内源性氮、磷的蓄积。人工湿地-池塘循环水养殖模式具有良好的生态效益,是一种绿色、可持续的养殖模式。 相似文献
9.
10.
浮游植物生长上行效应的研究进展 总被引：6，自引：0，他引：6
归纳了海洋浮游植物生长营养盐限制的研究方法,综述了国内外关于海水中氮、磷、硅、铁等营养元素限制浮游植物生长的研究结果。在氮、磷营养元素限制时,海水中上述两个元素的浓度不仅限制了浮游植物的生长,而且还改变了浮游植物的种群结构,随着营养盐浓度的降低,浮游植物从小型向微型、微微型转变;而硅的缺乏,使浮游植物由硅藻向非硅藻转变;在大洋海域,铁的限制,甚至还影响到浮游植物对常量营养盐的吸收。铁施肥虽然促进了浮游植物的生长,降低了大气中CO2的浓度,缓解了温室效应,但同时也伴随着有毒藻类的生长以及DM S气体增加等带来的诸多问题。 相似文献
11.
S. E. Fitzwater K. S. Johnson R. M. Gordon K. H. Coale W. O. Smith Jr. 《Deep Sea Research Part II: Topical Studies in Oceanography》2000,47(15-16)
Dissolved and particulate trace metal concentrations (dissolved Fe, Zn, Cd, Co, Cu and Ni; particulate Fe, Mn and Al) were measured along two transects in the Ross Sea during austral summer of 1990. Total Fe concentrations in southern Ross Sea and inshore waters were elevated >3.5 times that of northern waters. Dissolved Zn, Cd and Co concentrations were lower by factors of 4.5, 3.5 and 1.6 in southern surface waters relative to northern waters. Dissolved Cu and Ni concentrations were similar in both areas. Elevated Fe concentrations coincided with areas of increased productivity, phytoplankton biomass and nutrient drawdown, indicating that Fe is an important factor controlling the location of phytoplankton blooms in the Ross Sea. Particulate concentrations of Fe, Mn and Al indicate two possible sources of iron to the Ross Sea, resuspension of continental shelf sediments and iron incorporated in annual sea ice and released with meltwaters. 相似文献
12.
Distribution of Trace Bioelements in the Subarctic North Pacific Ocean and the Bering Sea (the R/V Hakuho Maru Cruise KH-97-2) 总被引：2，自引：1，他引：2
Yukiyo Fujishima Kazumasa Ueda Masahiro Maruo Ehchiro Nakayama Chikako Tokutome Hiroshi Hasegawa Masakazu Matsui Yoshiki Sohrin 《Journal of Oceanography》2001,57(3):261-273
A column concentration-high resolution inductively coupled plasma mass spectrometry (ICP-MS) determination was applied to measure the total dissolved concentrations of Fe, Co, Ni, Cu and Zn in seawater collected from the subarctic North Pacific (~45°N) and the Bering Sea in July–September 1997. Total adsorbable Mn was determined on board by column electrolysis preconcentration and chemiluminescence detection. The vertical profiles for Fe, Ni and Zn were nutrient-like. The deep water concentration of Fe was ~0.5 nM in the northeast Pacific (18°-140°W) and increased to ~1 nM in the northwest Pacific (161°E) and ~2 nM in the Bering Sea (57°N, 180°E). The deep water concentrations for Ni and Zn in the Bering Sea were also 1.3–2 times higher than in the North Pacific. The profiles for Co and Cu were examined in the subarctic North Pacific, and results obtained were consistent with previous reports. There was a significant correlation between the concentrations of Co and Mn except for surface mixed layer. The profiles for total adsorbable Mn were similar to the reported profiles for total dissolvable Mn. The deep water concentration of Mn in the Bering Sea was also 4 times higher than in the North Pacific. Iron and zinc were depleted in surface water of the subarctic North Pacific. The relationship between these trace elements and nutrients suggests that these elements could be a limiting factor of phytoplankton productivity. In the Bering Sea, surface water contained ~0.3 nM of Fe. The Zn concentration, which was less than the detection limit in surface water, increased at shallower depths (~30 m) compared with the subarctic North Pacific. These results imply a higher flux of Fe and Zn to surface water in the Bering Sea. This in turn may cause the ecosystem in the Bering Sea characterized by a dominance of diatoms and high regenerated production. 相似文献
13.
《Deep Sea Research Part II: Topical Studies in Oceanography》2009,56(26):2822-2838
During mesoscale Fe enrichment (SEEDS II) in the western North Pacific ocean, we investigated dissolved and particulate Co, Ni, Cu, Zn, Cd and Pb in seawater from both field observation and shipboard bottle incubation of a natural phytoplankton assemblage with Fe addition. Before the Fe enrichment, strong correlations between dissolved trace metals (Ni, Zn and Cd) and PO43−, and between particulate trace metals (Ni, Zn and Cd) and chlorophyll-a were obtained, suggesting that biogeochemical cycles mainly control the distributions of Ni, Zn and Cd in the study area. Average concentrations of dissolved Co, Ni, Cu, Zn, Cd and Pb in the surface mixed layer (0–20 m) were 70 pM, 4.9, 2.1, 1.6, 0.48 nM and 52 pM, respectively, and those for the particulate species were 1.7 pM, 0.052, 0.094, 0.46, 0.037 nM and 5.2 pM, respectively. After Fe enrichment, chlorophyll-a increased 3 fold (up to 3 μg L−1) during developing phases of the bloom (<12 days). Mesozooplankton biomass also increased. Particulate Co, Ni, Cu and Cd inside the patch hinted at an increase in the concentrations, but there were no analytically significant differences between concentrations inside and outside the patch. The bottle incubation with Fe addition (1 nM) showed an increase in chlorophyll-a (8.9 μg L−1) and raised the particulate fraction up to 3–45% for all the metals, accompanying changes in Si/P, Zn/P and Cd/P. These results suggest that Fe addition lead to changes in biogeochemical cycling of trace metals. The comparison between the mesoscale Fe enrichment and the bottle incubation experiment suggests that although Fe was a limiting factor for the growth of phytoplankton, the enhanced biomass of mesozooplankton also limited the growth of phytoplankton and the transformation of trace metal speciation during the mesoscale Fe enrichment. Sediment trap data and the elemental ratios taken up by phytoplankton suggest that export loss was another reason that no detectable change in the concentrations of particulate trace metals was observed during the mesoscale Fe enrichment. 相似文献
14.
The oceanic biogeochemical cycles of many trace elements are dominated by their association with the growth, death, consumption and sinking of phytoplankton. The trace element content of marine phytoplankton reflects nutritional status, species composition, surface area to volume ratios, and interactions with bioactive and toxic elements in the ambient seawater. Despite the ecological and environmental importance of trace element assimilation by autotrophs, there are few modern measurements of trace elements in phytoplankton assemblages from the natural environment. Here we introduce a new method for collection and analysis of size-fractionated particulate samples from practical seawater volumes. We pay particular attention to accurate determination of trace element filter blanks which are typically the limiting factor for analysis of such samples. Metals were determined at very low detection limits by high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for 11 elements (Ag, Al, Cd, Co, Cr, Cu, Fe, Mn, U, Zn and P, which is used as a biomass normalizer) in three types of polymer filters (0.45, 5.0, and 53 μm pore size) and a quartz fiber filter (0.8 μm pore size). To place these new determinations in a practical context, results are presented for a vertical profile of samples filtered from 1–4 l of coastal seawater (0.3–1.0 mg total solid dry weight) at a station off central California. The results demonstrate that the blanks of the evaluated filter types, precleaned appropriately, are sufficiently low to allow accurate determination of the trace metal content of three size-classes of phytoplankton. At the Pacific station, measured phytoplankton Zn content (as Zn/P) agrees with values predicted from single-species culture studies growing at seawater Zn concentrations expected for coastal waters. The new method has utility as a generally applicable and simple size fractionation technique, and allows determination of natural and pollutant elements in small samples of phytoplankton and particles in coastal, estuarine and offshore marine regimes. 相似文献
15.
九龙江口和厦门西港海域若干重金属元素的生物地球化学特性 总被引：6，自引：1，他引：6
根据１９８７年３月至１９８８年１２月九龙江口，厦门西港海域的调查资料，初步探讨该海域Ｆｅ，Ｍｎ，Ｃｕ，Ｚｎ，Ｎｉ，Ｃｏ，Ｐｂ，Ｃｄ等重金属元素的生物地球化学特性，及其与磷的生物地球化学的关系。结果表明该海域重金属元素的分布主要受九龙江径流的影响。在河水与海水混合过程中，悬浮颗粒态重金属元素发生明显转移，Ｆｅ，Ｍｎ，Ｃｏ，Ｚｎ等元素自悬浮颗粒物上解吸，Ｃｕ可能被吸附，颗粒态重金属元素与颗粒态磷呈良好 相似文献
16.
菊花岛周围海域38个站表层沉积物的铁、锰、铝、钛、磷、有机质、氮、铜、锌、铅、镉、镍和汞等化学要素含量的Q型因子分析计算表明,本区可划分为三个化学元素沉积区:1.海流悬浮沉积区;2.近岸波浪作用区;3.波浪海流作用区。柱状沉积物中铁等化学元素的迁移、富集受氧化——还原界面的控制。 相似文献
17.
流沙湾冬、春季大型海藻的微量元素分析 总被引：3，自引：0，他引：3
采用微波消解法和AFA、ICP-MS对流沙湾2008年冬春季21种大型海藻的微量元素进行了分析。结果表明,As、Cu、Pb、Cr、Se、Fe、Mn在细江蓠体内含量最高,分别为8.90、34.35、24.26、68.12、12.04、26777.20、400.16mg/kg;Hg在海蕴体内含量最高,达6.90mg/kg;Zn在鼠尾藻体内含量最高,为277.37mg/kg;Cd在石花菜体内含量最高,为6.77mg/kg;Ba在海门冬体内含量最高,为127.02mg/kg。各藻类对各重金属元素的综合富集能力由强到弱依次为细江蓠拟刚毛藻水云海蕴鼠尾藻海门冬条浒苔小珊瑚肠浒苔蜈蚣藻礁膜大石花菜石花菜半盐生单歧藻团扇藻长石莼宽扁叉节藻穗状鱼浒苔喇叭菜海头红刚毛藻,显示出藻类对各重金属元素综合富集能力因藻而异。各元素被藻类富集的量从大到小依次为FeMnBaZnCrCuPbAsSeCdHg,显示出藻类对营养元素的富集要大于对毒性元素的富集。各藻类对各重金属的富集系数从几倍至几十万倍不等,最高是细江蓠对Fe的富集,其次为海蕴对Hg的富集,最差为刚毛藻对Se的富集,其富集系数分别为204875.29、13800.00、3.48。聚类分析结果显示细江篱的富集能力最强,是多种重金属污染海域修复的首选生态环境材料。但对重金属复合污染海域进行生物修复,应有针对性地选择数种富集能力较强的大型海藻组成修复生物群落。 相似文献
18.
J. N. Pattan G. Parthiban Ankeeta Amonkar Sufiyan A. Shaikh S. Jai Sankar 《Marine Georesources & Geotechnology》2017,35(8):1147-1157
Thirty-three bulk ferromanganese nodules from the sediment–water interface of siliceous sediment domain from the Central Indian Ocean Basin were analyzed for 50 elements including 6 new (Be, As, Se, Sn, Sb, and Bi) using inductively coupled plasma–mass spectrometer. The Mn/Fe ratio and triangular plot (Fe-Mn-{Cu+Ni+Co?×?10}) suggest that ferromanganese nodules are of hydrogenetic, early diagenetic, and diagenetic origin. In the ferromanganese nodules, Mo, Sb, Bi, and As are highly enriched ～320, 160, 90, and 50 times compared with upper continental crust, respectively. A majority of the elements such as Be, Sc, Ti, V, Co, As, Se, Sr, Y, Zr, Nb, Sn, rare earth elements (REEs), Pb, Bi, P, Th, U, Hf, and Ta are associated with Fe, whereas, Cu, Ni, Zn, Mo, Li, Ga, Sb, Mg, and Cs are associated with Mn in the ferromanganese nodules. Redox proxies such as U/Th (0.14) and Mo/Mn (0.0019) ratio in the ferromanganese nodules suggest their formation under oxic conditions. 相似文献
19.
Samples of anoxic intertidal sediments from the Mersey Estuary, north-west England, have been used in laboratory experiments to determine the rates and extents of metal (Cu, Zn, Fe, Mn) releases to solution under conditions of controlled resuspension and reoxidation. An experimental system for the study of sediment-water interactions at various temperatures, salinities, pHs and oxygen concentrations is described. The results indicate rapid initial losses of Fe and Mn from sediment but not Cu and Zn with longer term readsorption of Fe and Mn to give partitioning between the aqueous/ sediment phases for all four metals which is similar to that under the initial anoxic conditions. Cu and Zn show small, but measurable, net losses from the aqueous phase to the reoxidized sediment. Salinity variations exert little influence on the processes observed, but increasing temperature produces increased Cu, Zn and Mn in the dissolved fraction at equilibrium conditions. Exchanges of Cu and Zn between the sediment/water phases are rather insensitive to pH or oxygen concentration, but Fe and Mn do respond to increasing pH which suppresses their initial release on oxidation. Low oxygen concentrations can result in a slow but significant release of Fe. In relation to trace metal pollution in estuaries and biological availability, the results suggest that the resuspension and oxidation of polluted anoxic sediments is not an important process because of scavenging of soluble metals on to the resuspended material. 相似文献
20.
Results of the analyses of the water column and sediments of the Bermuda Platform for Cd, Cu, Fe, Mn, Ni, Pb and Zn are presented. The major process controlling the water column concentrations is physical mixing of open ocean waters with inshore waters, which are polluted by a wide range of diffuse inputs. Sedimentation within the inshore waters plays a lesser, but significant, role as do fluxes from the sediments of Fe and Mn and possibly phytoplankton uptake of Zn. Concentrations within the sediments are controlled by the formation of trace metal enriched clay/organic particles in the inshore areas and their subsequent redistribution by sediment resuspension, except for Fe and Mn which are largely associated with clay lattices. 相似文献