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1.
本研究于2020年夏、秋两季,在黄海的三个站位开展了船基受控培养实验,研究了灰霾颗粒添加和光照变化(相较于海面约40%、68%和82%的光衰减)对微微型浮游植物生长、群落演替及碳生物量和叶绿素a(Chl a)比值的影响。结果表明,微微型浮游植物均表现出对总Chl a相当甚至主导的贡献能力,且所有培养站位初始海水中微微型浮游植物优势类群均为微微型真核浮游植物和聚球藻。在黄海中部和北部的贫营养海域,灰霾颗粒添加提供的氮能够促进微微型浮游植物的Chl a(Chl apico)浓度、微微型真核浮游植物和聚球藻细胞丰度的增加,但光照变化的影响不显著。然而,微微型浮游植物碳生物量(Cpico)和Chl apico比值(Cpico/Chl apico)随着灰霾颗粒的添加和光照强度的衰减呈降低趋势,这与浮游植物的光合色素合成水平密切相关。在近岸富营养海域,培养实验期间海面的光照强度较低,且由于海域水体浑浊,光照强度是影响微微型浮游植物生长和Cpico/Chl a... 相似文献
2.
渤海海面太阳辐照强度的观测分析与计算方法研究 总被引：8，自引：2，他引：8
对渤海海面(1998-09-24～10-07和1999-04-28～05-11)实测太阳辐射日总量同云量的关系和春、秋季的对比关系及其与插值计算出的晴日太阳辐射日总量的关系进行了分析,并同烟台(福山)测站的结果进行了对比分析.通过分析发现,渤海海面太阳辐射日总量春季远大于秋季,其无云条件下的太阳辐射日总量与插值计算出的晴日太阳辐射日总量的差异秋季大于春季.分析表明,海陆温差引起的海面大气垂直输送与水汽物的产生是造成这种差异的主要原因.采用经验公式对渤海海面太阳辐射日总量进行计算,计算结果与实测结果具有较好的一致性.结果表明所用经验公式及推算出的参数适合于春、秋季渤海海面太阳辐照度的计算. 相似文献
3.
基于水色遥感的黄、东海叶绿素a浓度季节和年际变化特征分析 总被引：2，自引：1，他引：1
海洋叶绿素a浓度是衡量海洋浮游植物的生物量和富营养化程度的最基本指标之一。黄、东海叶绿素a浓度年际变化显著,其影响因素需深入分析。本文依据黄、东海的地理位置、水深和生态特征将其分为5个区域进行研究。由5个区域叶绿素a浓度的季节变化可以看出,水华发生早晚依次是黄海西岸—北黄海中部—南黄海中部—东海陆架区—东海近岸海区。从年际变化可以看出,除东海陆架外,其它4个区域的变化幅度均较大。在冬季和夏季,5个区域的基础生物量在2008年均达到最低;在春季和秋季,黄、东海近岸和北黄海中部的年际变化较大,5个区域在2006年春季均达到最高;2009年秋季较其它年份均低。5个区域基础生物量由高到低为:黄、东海近岸较高,然后是北黄海中部和南黄海中部,东海陆架最低。从与水温、风速和有效光合辐射的相关分析来看,浮游植物生长的年际变化受海面风速的影响较大。近岸区域水体混合均匀,营养盐丰富,风速较小时水体稳定有利于浮游植物生长,而水深较深区域,风速较大时,营养盐易补充到表层,有利于浮游植物生长。 相似文献
4.
南黄海夏初网采浮游植物分布与长期变化 总被引：1，自引：0，他引：1
本文根据2012和2013年夏初南黄海网采浮游植物调查数据,与1959、2002及2003年的调查资料作比较,研究了南黄海海域浮游植物的分布和长期变化规律。结果表明,浮游植物生物量的年际变化波动较大,1959年全国海洋综合调查时期的浮游植物生物量显著低于2012—2013年的生物量。2013年浮游植物平均丰度和碳含量最高,分别为(18.73±46.68)×104cell/m3和(1110.71±2107.82)μg C/m3。近岸海域的浮游植物对南黄海浮游植物总生物量有主要贡献。1959年,硅藻在群落中的丰度比例大于93%,而2012—2013年,这一比例下降为50%—60%。相应地,硅藻碳含量比例由70%—85%下降为18%—28%,且甲藻占优势的区域扩大。硅藻碳含量比例在群落中明显下降一方面是因为硅藻碳密度相对较低,另一方面是因为甲藻丰度的增大。相对于1959年,近年来硅藻中的角毛藻属(Chaetoceros)和伪菱形藻属(Pseudonitzschia),以及甲藻中的角藻属(Ceratium)和夜光藻属(Noctiluca)成为新的优势种属。与环境因子的相关性分析表明,影响南黄海夏初浮游植物群落分布的关键环境因子为温度、盐度、硅酸盐和溶解性无机氮。 相似文献
5.
渤海浮游植物生物量季节变化的模拟研究 总被引：1，自引：0，他引：1
在近海生态系统中,浮游植物生物量的季节变化仍然缺乏全面的机制解释。为研究渤海生态系统中浮游植物生物量季节变化的影响机制,建立了1个包括营养盐(无机氮)、浮游植物、浮游动物、底碎屑4种生物变量的箱式模型,模拟了渤海1983年浮游植物生物量的季节变化,再现了浮游植物生物量一年内的双峰分布。通过对模型参数敏感性的定量和定性分析,讨论了模型对不同生物参数的敏感性,发现模型对浮游植物最大生长率、浮游植物最大死亡率、浮游植物吸收营养盐的半饱和系数最敏感。通过一系列数值试验,进一步讨论了理化因子对渤海浮游植物生物量季节变化的影响,发现理化因子的改变不仅影响浮游植物生物量的大小,也决定了其季节变化的特征。 相似文献
6.
利用高光谱监测数据反演浮游植物种群组成是当前海洋光学和水色遥感的研究热点。文章采用大西洋经向断面航次中走航式观测系统测量的海水总颗粒物吸收光谱数据, 尝试建立了两种模型对浮游植物粒级结构(Phytoplankton size class, 简称PSC)进行反演和比较讨论。一类模型是基于总颗粒物吸收光谱高斯分解获得的典型波段高斯带强度与色素浓度之间的关系, 建立了偏最小二乘回归模型(Partial Least Squares regression model, 简称PLS回归模型); 另一类模型是采用长波波段吸收基线高度推算海水总叶绿素a浓度, 进而根据Brewin等(2010) 生物量算法推算PSC的三组分模型(简称三组分模型)。模型比较验证结果显示, 两类模型对海水总叶绿素浓度的反演都有较高的精度, 相对偏差ME在15%左右; 对于三个粒级浮游植物对应的叶绿素浓度(Pico级Cp, Nano级Cn, Micro级Cm)的反演效果也相当, PLS回归模型反演的ME分别为28.4%、31.9%和41%, 三组分模型反演的ME分别为31%、35.9%、37.7%。研究结果初步表明了采用高光谱吸收系数反演浮游植物种群结构的潜在优势, 可为不同海域走航式高光谱观测系统的推广应用提供思路。 相似文献
7.
石油烃污染物对海洋浮游植物生长的影响--实验与模型 总被引：3，自引：3，他引：3
本文应用 1次培养实验方法 ,研究了 No.0柴油石油烃污染物对 6种海洋浮游植物生长的影响 ,结果表明 ,高浓度石油烃污染物 (CPH>1.0 5 mg· dm-3 )对裸甲藻 ,新月菱形藻 ,三角褐指藻 ,小球藻和亚心形扁藻的生长有抑制作用 ,对于中肋骨条藻 ,石油烃污染物浓度在高于 1.96 mg· dm-3 时抑制其生长。但低浓度石油烃污染物则易促进赤潮藻类 (裸甲藻 ,新月菱形藻 ,中肋骨条藻 )的生长。在 Logistic生长模型的基础上 ,结合 L orentz方程和 Exponential方程 ,引入石油烃污染物浓度项 ,建立石油烃污染物条件下的海洋浮游植物生长的模型。Lorentz方程可描述石油烃污染物对浮游植物生长速率参数的影响 ,Exponential方程可描述石油烃污染物对浮游植物生物量的影响 ,并且实验验证了该模型 相似文献
8.
利用特征色素研究长江口海域浮游植物对营养盐加富的响应 总被引：3，自引：1，他引：2
于2009年5月和11月,在长江口邻近海域通过现场营养盐加富实验,研究了浮游植物对营养盐添加的响应。应用高效液相色谱技术分析培养样品中的特征色素组成,通过CHEMTAX软件估算了硅藻、甲藻、隐藻、定鞭藻、金藻、绿藻、青绿藻和蓝藻8个浮游植物类群对叶绿素a生物量的贡献(μg/L)。加富实验结果显示:不同海区或同一海区不同季节的浮游植物生长对营养盐响应不尽相同,这与培养实验水样采集时浮游植物所处的N、P限制状态有着密切的关系。营养盐的加富不仅能够促进浮游植物生物量的增加,也可能引起浮游植物的群落结构的变化。不同浮游植物类群对营养盐添加的敏感性不同,培养实验开始后营养盐的输入使得硅藻在竞争中取得了优势,硅藻所占比重明显上升;但随着培养的进行,营养盐逐渐消耗,一些在低营养条件下竞争能力强的浮游植物类群比如甲藻、蓝藻、隐藻等对生物量的贡献逐渐上升;同时,培养海水中初始浮游植物群落组成对营养盐加富后群落结构的变化有着重要的影响。 相似文献
9.
A.水环境和水生生物的剂量率根据在本刊上一期介绍的计算模式计算了水生环境及水生生物的剂量率。表15—29是IAEA专家小组对水环境和水生物所计算的剂量率。可以利用海水中的~(238)U,通过几何模型来计算浮游植物、浮游动物、甲壳动物、软体 相似文献
10.
琼东上升流（EHU）是南海北部最强劲的上升流系统之一。它的水动力过程已经被很多研究所揭示，但是它的浮游植物群落依然不清楚。通过利用卫星遥感数据和2015年上升流季节的航次数据，我们首次阐明了琼东上升流区域（EHU）和其临近区域雷州半岛东部上升流区（ELPU）浮游植物生物量和群落的空间结构。在夏季季风的驱动下，我们在琼东沿岸发现了一个显著的低温高盐冷舌。由于雷州半岛东部大陆架宽广平缓，ELPU比EHU相对较弱。在EHU,由于受潮汐和风浪混合的影响，高溶解氧浓度 (>6.0 mg/l)几乎从表层延伸到30米深度。其次，低溶解氧的海水(<6.0 mg/l, 缺氧)被上升流从底层抽吸到上层。ELPU和EHU相比有更差的DO状况，在EHU，底层DO浓度由于大量的消耗，浓度甚至低于3.5 mg/l。在EHU，浮游植物生物量最大值出现在30米水层而不是在表层，约为1.5 mg/m3。这表明了上升流对于浮游植物生长和DO分布的影响范围。由于营养物质输入丰富， ELPU处的浮游植物生物量比EHU高很多。在EHU处，浮游植物生物量最大值可以达到4.0 mg/m3。浮游植物生物量在EHU和ELPU的沿岸区域则降低到了大约0.2~0.3 mg/m3，而这个值与远海接近。在EHU的近岸，浮游植物群落结构被硅藻所主宰，大约占了浮游植物生物量的50%。原核生物（大约40%）、绿藻（大约20%）、原绿球藻（大约20%）组成了EHU的近岸的主要群落。在ELPU,硅藻大约占了浮游植物生物量的80%，其次是绿藻，这表明与EHU相比，这个区域是一个相对不同的生态系统。 相似文献
11.
A five-year study of the interannual changes observed in May–June during the mass reproduction of coccolithophorids was carried
out in the northeastern part of the Black Sea. The long-term dynamics were analyzed using the data on the phytoplankton collected
during the last 40 years. The fraction of coccolithophorids represents either 20 or 60% of the total biomass of the algae
and does not depend on either the previous winter conditions or the nitrogen content and the N: P ratio in the surface water
layer. Our studies have revealed the dependency between the phosphate content and the size of the coccolythophorids’ fraction
in the total phytoplankton biomass. The long-term population dynamics includes three periods. Until the mideighties, the coccolythophorid
fraction in the Black Sea phytoplankton was insignificant (3%). The average biomass was equal to 8 μg/l. In the late eighties,
the average biomass increased up to 106 μg/l. Since the midnineties, coccolythophorids often prevail in the number and mass
among the other phytoplankton species. The general tendency for the growth of the coccolythophorid fraction in the phytoplankton
cenoses coincides with the increase in the phosphate concentration in the near-surface water observed within the last 40 years.
This fact corresponds to the experimental results, which demonstrate that the coccolythophorid development during May–June
is phosphate-limited. 相似文献
12.
13.
A two-dimensional steady-state model of light-driven phytoplankton productivity and biomass in partially mixed estuaries has been developed. Effects of variations in river flow, suspended sediment concentration, phytoplankton sinking, self-shading and growth rates on distributions of phytoplankton biomass and productivity are investigated.Numerical simulation experiments show that biomass and productivity are particularly sensitive to variations in suspended sediment concentrations typical of natural river sources and to variations in loss rates assumed to be realistic but poorly known for real systems. Changes in the loss rate term within the range of empirical error (such as from dark bottle incubation experiments) cause phytoplankton biomass to change by a factor of two. In estuaries with adequate light penetration in the water column, it could be an advantage for phytoplankton to sink. Species that sink increase their concentration and form a phytoplankton maximum in a way similar to the formation of the estuarine turbidity maximum. When attenuation is severe, however, sinking species have more difficulty in maintaining their population. 相似文献
14.
《African Journal of Marine Science》2013,35(1):327-336
Eastern and central Agulhas Bank waters are characterized by strong, shallow thermoclines and well developed subsurface maxima of phytoplankton biomass. The thermoclines are advectively maintained and as such are dynamically stable, but they do exhibit short-term variations in absolute temperature gradients. There are corresponding variations in subsurface phytoplankton biomass maxima. The water-column phytoplankton production maxima are generally situated in the biomass maxima because these are sufficiently shallow to ensure adequate light. Self-shading becomes a limiting factor with the development of high phytoplankton biomasses. Western Agulhas Bank waters are characterized by deeper thermoclines and less intense subsurface maxima of phytoplankton biomass. Due to the depth of the thermoclines the biomass maxima are generally situated below the depth of the 1-per-cent surface light intensity and, consequently, phytoplankton production is limited. Possible mechanisms for the maintenance of these deep chlorophyll maxima are discussed. 相似文献
15.
Experiments on the effects of nitric oxide （NO） and iron on the growth of marine microalgae Skeletonema costatum were conducted. The results are as follows： exogenous NO could increase the growth rate of marine algae and raise the biomass remarkably under iron-deficient conditions. But it was a complicated process that the phytoplankton growth was influenced by NO and iron, which was controlled by the NO concentration, the nutrition level of the culture medium and the iron concentration, etc. Meanwhile, the iron concentration in the medium also has a direct influence on the growth and NO release capacity of the algae. Therefore, the effects of NO and iron on the growth of marine phytoplankton were mutual. 相似文献
16.
Heather A. Bouman Toru Nakane Kenji Oka Kisaburo Nakata Kiyo Kurita Shubha Sathyendranath Trevor Platt 《Estuarine, Coastal and Shelf Science》2010
Phytoplankton biomass and primary production were examined in their environmental context, for a semi-enclosed bay (Tokyo Bay, Japan) using data from monthly samples collected over a three-year period. Heavy precipitation and high surface temperatures in the late spring and summer gave rise to a highly-stratified water-column and stimulated a series of phytoplankton blooms, whereas during the winter, a weakly-stratified and deeply-mixed water-column led to a rapid decline in phytoplankton biomass under light-limited growth conditions. By incorporating pigment, photophysiological and optical data into a primary production model we show that daily, water-column primary production ranges from ∼160 mg C m−2 d−1 to 7600 mg C m−2 d−1. High water turbidity and deep vertical mixing, both separately and in concert, limit the light available for algal growth over much of the year. Annual primary production varied from 370 to 580 g C m−2 y−1. The relative influences of nutrient limitation and light limitation are assessed. A model is developed that describes this in an explicit manner using photophysiological parameters. 相似文献
17.
Jill Peloquin Julie HallKarl Safi Michael Ellwood Cliff S. LawKaren Thompson Jorma KuparinenMichael Harvey Stuart Pickmere 《Deep Sea Research Part II: Topical Studies in Oceanography》2011,58(6):824-838
The SOLAS Air-Sea Gas Exchange (SAGE) experiment was conducted in Sub-Antarctic waters off the east coast of the South Island of New Zealand in the late summer of 2004. This mesoscale iron enrichment experiment was unique in that chlorophyll a (chl a) and primary productivity were only 2× OUT stations values toward the end of the experiment and this enhancement was due to increased activity of non-diatomaceous species. In addition, this enhancement in activity appeared to occur without a significant build up of particulate organic carbon. Picoeukaryotes (<2 ??m) were the only members of the phytoplankton assemblage that showed a statistically significant increase, a doubling in biomass. To better understand the controls of phytoplankton growth and biomass, we present results from a series of on-deck perturbation experiments conducted during SAGE. Results suggest that the pico-dominated phytoplankton assemblage was only weakly inhibited by iron. Diatoms with high growth rates comprised a small (<1%) fraction of the phytoplankton assemblage, were likely iron limited, and potentially further limited by silicic acid and therefore did not significantly contribute to bloom dynamics. On deck experiments and comparison of SAGE with other iron addition experiments suggested that neither light availability nor deep mixed layers limited phytoplankton growth. Although no substantial increase in grazing rate or specific phytoplankton growth rate was detected, microzooplankton biomass doubled over SAGE as a result of an increase in cell size. The importance of microzooplankton grazing was highlighted by the fact that they were capable of consuming 15-49% of the total phytoplankton production per day. Removal was highest on eukaryotic picophytoplankton production with a mean value of 72% (29-143%). Patch dilution played an important role during SAGE; the mean patch net algal growth:dilution rate, 1.13 (0.4-2.2) was the lowest reported for a mesoscale iron enrichment experiment. Phytoplankton biomass, estimated by chlorophyll a, only accumulated when phytoplankton growth exceeded grazing and when net algal growth exceeded dilution rate. The SAGE results highlight the function of the smallest phytoplankton size fraction described by the ecumenical Iron Hypothesis. Thus, adding iron to HNLC-low silicic acid regions during certain times of the year may simply transfer more carbon through the microbial food web. A primary implication of this study is that any iron-mediated gain in fixed carbon with this set of environmental conditions has a high probability of being recycled in surface waters. 相似文献
18.
《Deep Sea Research Part II: Topical Studies in Oceanography》2009,56(26):2936-2947
Several in situ iron-enrichment experiments have been conducted, where the response of the phytoplankton community differed. We use a marine ecosystem model to investigate the effect of iron on phytoplankton in response to different initial plankton conditions and mixed-layer depths (MLDs). Sensitivity analysis of the model results to the MLDs reveals that the modeled response to the same iron enhancement treatment differed dramatically according to the different MLDs. The magnitude of the iron-induced biogeochemical responses in the surface water, such as maximum chlorophyll, is inversely correlated with MLD, as observed. The significant decrease in maximum surface chlorophyll with MLD results from the difference in diatom concentration in the mixed layer, which is determined by vertical mixing. The modeled column-integrated chlorophyll, on the other hand, is the highest with intermediate MLD cases, suggesting difference in iron-induced biogeochemical responses between volume and area considerations. The iron-induced diatom bloom is severely restricted below the compensation depth due to both light limitation and grazing pressure, irrespective of the MLD. Sensitivity of the model to initial mesozooplankton (as grazers on diatoms) biomass shows that column-integrated biomass, net community production and export production are strongly controlled by the initial mesozooplankton biomass. Higher initial mesozooplankton biomass yields high grazing pressure on diatoms, which results in less accumulation of diatom biomass and may account for notably lower surface chlorophyll during SEEDS (Subarctic Pacific Iron Experiment for Ecosystem Dynamics Study) II than during SEEDS. The initial diatom biomass is also important to the outcome of iron enrichment but is not as crucial as the MLD and the initial mesozooplankton biomass. This modeling study suggests that not only MLD but also the initial biomass of diatoms and its principle grazers are crucial factors in the response of the phytoplankton community to iron enrichments, and should be considered in designing future iron-enrichment experiments. 相似文献
19.
The problem of recognition of algal genera based on the remote sensing data requires the analysis of the algae biomass’s distribution.
This study provides the analysis of the algae spatial and temporal variations in the Peter the Great Bay. While 116 algal
genera were observed, only a few genera have dominated. Usually, the dominant genus contributed about 60% of the sample’s
biomass (the minimal value is 20% usually) and 4 dominant genera contributed about 90% of the total phytoplankton biomass.
The effective scattering crosssection of the algae in the samples is very changeable and this feature looks promising for
the recognition problem. It was found that the spatial and temporal variations of the algal biomass are significant, but the
percentage characteristics of a few dominant genera are relatively stable with no significant dependence on a region and a
biomass value. The algae’s composition analysis has demonstrated that the same algal genera are propagated in different parts
of the Bay. For a given region and month, the set of algae dominated that constitutes about 90% of the monthly biomass is
rather small (not more than 10 genera usually). Most of the alga genera (∼75%) do not ever reach a mono domination state (more
than 50% of the sample’s biomass). 相似文献