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1.
Sub-Lethal Effects of Elevated Concentration of CO<Subscript>2</Subscript> on Planktonic Copepods and Sea Urchins 总被引：2，自引：0，他引：2
Data concerning the effects of high CO2 concentrations on marine organisms are essential for both predicting future impacts of the increasing atmospheric CO2 concentration and assessing the effects of deep-sea CO2sequestration. Here we review our recent studies evaluating the effects of elevated CO2 concentrations in seawater on the mortality and egg production of the marine planktonic copepod, Acartia steueri, and on the fertilization rate and larval morphology of sea urchin embryos, Hemicentrotus pulcherrimus and Echinometra mathaei. Under conditions of +10,000 ppm CO2 in seawater (pH 6.8), the egg production rates of copepods decreased significantly. The survival rates of adult copepods
were not affected when reared under increased CO2 for 8 days, however longer exposure times could have revealed toxic effects of elevated CO2 concentrations. The fertilization rate of sea urchin eggs of both species decreased with increasing CO2 concentration. Furthermore, the size of pluteus larvae decreased with increasing CO2 concentration and malformed skeletogenesis was observed in both larvae. This suggests that calcification is affected by elevated
CO2 in the seawater. From these results, we conclude that increased CO2 concentration in seawater will chronically affect several marine organisms and we discuss the effects of increased CO2 on the marine carbon cycle and marine ecosystem.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
2.
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Feasibility studies recently suggest that sequestration of anthropogenic CO2 in the deep ocean could help reduce the atmospheric CO2 concentration. However, implementation of this strategy could have a significant environmental impact on marine organisms.
This has highlighted the urgent need of further studies concerning the biological impact of CO2 ocean sequestration. In this paper we summarize the recent literature reporting on the biological impact of CO2 and discuss the research work required for the future. Although fundamental research of the effect of CO2 on marine organisms before the practical consideration of CO2 ocean sequestration was limited, laboratory and field studies concerning biological impacts have been increasing after the
first international workshop in 1991 discussing CO2 ocean sequestration. Acute impacts of CO2 ocean sequestration could be determined by laboratory and field experiments and assessed by simulation models as described
by the following papers in this section. On the other hand, chronic effects of CO2 ocean sequestration, those directly related to the marine ecosystem, would be difficult to verify by means of experiments
and to assess using ecosystem models. One of the practical solutions for this issue implies field experiments starting with
controlled small scale and eventually to a large scale of CO2 injection intended to determine ecosystem alteration.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
Atsushi Ishimatsu Takashi Kikkawa Masahiro Hayashi Kyoung-Seon Lee Jun Kita 《Journal of Oceanography》2004,60(4):731-741
CO2-enriched seawater was far more toxic to eggs and larvae of a marine fish, silver seabream, Pagrus major, than HCl-acidified seawater when tested at the same seawater pH. Data on the effects of acidified seawater can therefore
not be used to estimate the toxicity of CO2, as has been done in earlier studies. Ontogenetic changes in CO2 tolerance of two marine bony fishes (Pag. major and Japanese sillago, Sillago japonica) showed a similar, characteristic pattern: the cleavage and juvenile stages were most susceptible, whereas the preflexion
and flexion stages were much more tolerant to CO2. Adult Japanese amberjack, Seriola quinqueradiata, and bastard halibut, Paralichthys olivaceus, died within 8 and 48 h, respectively, during exposure to seawater equilibrated with 5% CO2. Only 20% of a cartilaginous fish, starspotted smooth-hound, Mustelus manazo, died at 7% CO2 within 72 h. Arterial pH initially decreased but completely recovered within 1-24 h for Ser. quinqueradiata and Par. olivaceus at 1 and 3% CO2, but the recovery was slower and complete only at 1% for M. manazo. During exposure to 5% CO2, Par. olivaceus died after arterial pH had been completely restored. Exposure to 5% CO2 rapidly depressed the cardiac output of Ser. quinqueradiata, while 1% CO2 had no effect. Both levels of ambient CO2 had no effect on blood O2 levels. We tentatively conclude that cardiac failure is important in the mechanisms by which CO2 kills fish. High CO2 levels near injection points during CO2 ocean sequestration are likely to have acute deleterious effects on both larvae and adults of marine fishes.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
5.
James P. Barry Kurt R. Buck Chris F. Lovera Linda Kuhnz Patrick J. Whaling Edward T. Peltzer Peter Walz Peter G. Brewer 《Journal of Oceanography》2004,60(4):759-766
Purposeful deep-sea carbon dioxide sequestration by direct injection of liquid CO2 into the deep waters of the ocean has the potential to mitigate the rapid rise in atmospheric levels of greenhouse gases.
One issue of concern for this carbon sequestration option is the impact of changes in seawater chemistry caused by CO2 injection on deep-sea ecosystems. The effects of deep-sea carbon dioxide injection on infaunal deep-sea organisms were evaluated
during a field experiment in 3600 m depth off California, in which liquid CO2 was released on the seafloor. Exposure to the dissolution plume emanating from the liquid CO2 resulted in high rates of mortality for flagellates, amoebae, and nematodes inhabiting sediments in close proximity to sites
of CO2 release. Results from this study indicate that large changes in seawater chemistry (i.e. pH reductions of ∼0.5–1.0 pH units)
near CO2 release sites will cause high mortality rates for nearby infaunal deep-sea communities.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
6.
The responses of atmospheric pCO2 and sediment calcite content to changes in the export rain ratio of calcium carbonate to organic carbon are examined using
a diffusion-advection ocean biogeochemical model coupled to a one-dimensional sediment geochemistry model. Our model shows
that a 25% reduction in rain ratio decreases atmospheric pCO2 by 59 ppm. This is caused by alkalinity redistribution by a weakened carbonate pump and an alkalinity increase in the whole
ocean via carbonate compensation with decreasing calcite burial. The steady state responses of sedimentary calcite content
and calcite preservation efficiency are rather insensitive to the deepening of the saturation horizon of 1.9 km. This insensitivity
is a result of the reduced deposition flux that decreases calcite burial, counteracting the saturation horizon deepening that
increases calcite burial. However, in the first 10,000 years the effect of reduced calcite deposition on the burial change
is more prominent; while after 10,000 years, the effect of saturation horizon deepening is more dominant. The lowering of
sediment calcite content for the first 10,000 years is effectively decoupled from the 1.9 km downward shift of the saturation
horizon. Our results are in part a consequence of the more dominant role that respiration CO2 plays in sediment calcite dissolution over bottom water chemistry in our control run and support the decoupling of calcite
lysocline depth and saturation horizon shifts, as suggested originally by Archer and Maier-Reimer (1994) and Archer et al. (2000). 相似文献
7.
To study the biological impacts of CO2 ocean sequestration on floating marine organisms, a full Eulerian-Eulerian scheme model has been developed in a large-eddy
simulation (LES) version using one-way coupling of the equations of seawater flow to the transport equations of the bio-scalar
variables. Special attention was paid to deriving the transport equation, involving non-conservative scalars to describe the
degree of injury to floating organisms due to the change in the pH environment resulting from CO2 dissolution. The source terms of the transport equations of bio-scalar variables are based on experimental data on zooplankton
activities affected by lower pH seawater, allowing construction of empirical sub-models of three kinds of floating marine
organisms: Gaidius variabilis, Paraeuchaeta Birostrata, and Multi-organisms. An example is given to show the applicability
of the model to the assessment of the biological impact of CO2 sequestration in the ocean. Given an initial CO2 droplet diameter of 8.0 mm and an injection rate of 1.0 kg/sec, the model simulation predicts that the zooplanktons lose
approximately 90% of their activity when the lowest pH inside the plume decreases from 7.57 to 5.61. These injured zooplanktons
then recovered gradually to their normal state within two hours due to dilution of the plume.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
8.
Calcification in the marine environment is the basis for the accretion of carbonate in structures such as coral reefs, algal ridges and carbonate sands. Among the organisms responsible for such calcification are the Corallinaceae (Rhodophyta), recognised as major contributors to the process world-wide. Hydrolithon sp. is a coralline alga that often forms rhodoliths in the Western Indian Ocean. In Zanzibar, it is commonly found in shallow lagoons, where it often grows within seagrass beds and/or surrounded by green algae such as Ulva sp. Since seagrasses in Zanzibar have recently been shown to raise the pH of the surrounding seawater during the day, and since calcification rates are sensitive to pH, which changes the saturation state of calcium carbonate, we measured the effects of pH on photosynthetic and calcification rates of this alga. It was found that pH had significant effects on both calcification and photosynthesis. While increased pH enhanced calcification rates both in the light and in the dark at pH >8.6, photosynthetic rates decreased. On the other hand, an increase in dissolved CO2 concentration to 26 μmol kg−1 (by bubbling with air containing 0.9 mbar CO2) caused a decrease in seawater pH which resulted in 20% less calcification after 5 days of exposure, while enhancing photosynthetic rates by 13%. The ecological implications of these findings is that photosynthetically driven changes in water chemistry by surrounding plants can affect calcification rates of coralline algae, as may future ocean acidification resulting from elevated atmospheric CO2. 相似文献
9.
Due to the elevated atmospheric carbon dioxide, ocean acidification(OA) has recently emerged as a research theme in marine biology due to an expected deleterious effect of altered seawater chemistry on calcification. A system simulating future OA scenario is crucial for OA-related studies. Here, we designed an OA-simulated system(OASys) with three solenoid-controlled CO2 gas channels. The OASys can adjust the pH of the seawater by bubbling CO2 gas into seawaters via feedback systems. The OASys is very simple in structure with an integrated design and is new-user friendly with the instruction. Moreover, the OASys can monitor and record real-time pH values and can maintain pH levels within 0.02 pH unit. In a 15-d experiment, the OASys was applied to simulate OA in which the expected target pH values were 8.00, 7.80 and 7.60 to study the calcifying response of Galaxea fascicularis. The results showed daily mean seawater pH values held at pH 8.00±0.01, 7.80±0.01 and 7.61±0.01 over15 d. Correspondingly, the coral calcification of G. fascicularis gradually decreased with reduced pH. 相似文献
10.
An increase in the level of atmospheric carbon dioxide (CO2) and the resultant rise in CO2 in seawater alter the inorganic carbon concentrations of seawater. This change, known as ocean acidification, ... 相似文献
11.
The ocean captures a large part of the anthropogenic carbon dioxide emitted to the atmosphere. As a result of the increase in CO2 partial pressure the ocean pH is lowered as compared to pre-industrial times and a further decline is expected. Ocean acidification has been proposed to pose a major threat for marine organisms, particularly shell-forming and calcifying organisms. Here we show, on the basis of meta-analysis of available experimental assessments, differences in organism responses to elevated pCO2 and propose that marine biota may be more resistant to ocean acidification than expected. Calcification is most sensitive to ocean acidification while it is questionable if marine functional diversity is impacted significantly along the ranges of acidification predicted for the 21st century. Active biological processes and small-scale temporal and spatial variability in ocean pH may render marine biota far more resistant to ocean acidification than hitherto believed. 相似文献
12.
Hideyuki Nakano Hiroyuki Tsujino Mikitoshi Hirabara Tamaki Yasuda Tatsuo Motoi Masao Ishii Goro Yamanaka 《Journal of Oceanography》2011,67(6):765-783
The uptake mechanism of anthropogenic CO2 in the Kuroshio Extension is examined by a Lagrangian approach using a biogeochemical model embedded in an ocean general circulation model. It is found that the uptake of anthropogenic CO2 is caused mainly by the increase of pCO2 dependency of seawater on temperature, which is caused by greater dissolved inorganic carbon concentration in the modern state than in the pre-industrial state. In contrast with the view of previous studies, the effect of the vertical entrainment, which brings waters that last contacted the atmosphere with the past lower CO2 concentration, is comparatively small. Winter uptake of anthropogenic CO2 increases with the rise of the atmospheric CO2 level, while summer uptake is relatively stable, resulting in a larger seasonal cycle of the uptake. This increase is significant, especially in the Kuroshio Extension region. It is newly suggested that this increase in the Kuroshio Extension region is largely caused by the combined effects of the increased pCO2 dependency of the sea water on the temperature and the seasonal difference in cooling. 相似文献
13.
CO2 currently accumulating in the atmosphere permeates into ocean surface layers, where it may impact on marine animals in addition
to effects caused by global warming. At the same time, several countries are developing scenarios for the disposal of anthropogenic
CO2 in the worlds' oceans, especially the deep sea. Elevated CO2 partial pressures (hypercapnia) will affect the physiology of water breathing animals, a phenomenon also considered in recent
discussions of a role for CO2 in mass extinction events in earth history. Our current knowledge of CO2 effects ranges from effects of hypercapnia on acid-base regulation, calcification and growth to influences on respiration,
energy turnover and mode of metabolism. The present paper attempts to evaluate critical processes and the thresholds beyond
which these effects may become detrimental. CO2 elicits acidosis not only in the water, but also in tissues and body fluids. Despite compensatory accumulation of bicarbonate,
acid-base parameters (pH, bicarbonate and CO2 levels) and ion levels reach new steady-state values, with specific, long-term effects on metabolic functions. Even though
such processes may not be detrimental, they are expected to affect long-term growth and reproduction and may thus be harmful
at population and species levels. Sensitivity is maximal in ommastrephid squid, which are characterized by a high metabolic
rate and extremely pH-sensitive blood oxygen transport. Acute sensitivity is interpreted to be less in fish with intracellular
blood pigments and higher capacities to compensate for CO2 induced acid-base disturbances than invertebrates. Virtually nothing is known about the degree to which deep-sea fishes are
affected by short or long term hypercapnia. Sensitivity to CO2 is hypothesized to be related to the organizational level of an animal, its energy requirements and mode of life. Long-term
effects expected at population and species levels are in line with recent considerations of a detrimental role of CO2 during mass extinctions in the earth's history. Future research is needed in this area to evaluate critical effects of the
various CO2 disposal scenarios.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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为了评估海洋酸化和富营养化耦合作用对近海浮游生态环境的影响,本研究以天津市近岸海域浮游植物群落的生物地球化学指标为研究对象,分别采用一次性及连续培养的方式模拟自然水华及稳态条件,探究其对二氧化碳(CO2)和硝酸盐浓度变化及二者耦合作用的响应。实验条件设置如下:1)对照:二氧化碳分压p(CO2)40.53 Pa、无硝酸盐添加;2)酸化:p(CO2)101.3 Pa、无硝酸盐添加;3)加N:p(CO2)40.53 Pa、添加硝酸盐50 μmol·L–1;4)酸化加N:p(CO2)101.3 Pa、添加硝酸盐50 μmol·L–1。实验结果表明,硝酸盐加富比酸化更加显著地促进浮游植物群落总叶绿素(Chl a)生物量及颗粒有机碳(POC)和颗粒有机氮(PON)积累,酸化和加N使浮游植物群落粒径大小升高。连续培养实验表明,酸化和N加富对Chl a、生物硅(BSi)、PON浓度、PON与颗粒有机磷(POP)比值(N/P)、POC与BSi比值(C/BSi)及沉降速率有协同交互作用,对POP和POC浓度及POC与PON比值(C/N)有拮抗性交互作用。在一次性培养后,酸化显著降低了浮游植物群落的沉降速率;而在连续培养后,酸化和N加富使浮游植物群落沉降速率显著升高。这些结果表明酸化和N加富对与近岸浮游植物相关的生物地球化学循环及在不同生长阶段的种群碳沉降存在不同的潜在影响及交互效应。 相似文献
16.
Climate change is a threat to marine biota because increased atmospheric CO2 is causing ocean warming, acidification, hypercapnia and decreased carbonate saturation. These stressors have toxic effects on invertebrate development. The persistence and success of populations requires all ontogenetic stages be completed successfully and, due to their sensitivity to environmental stressors, developmental stages may be a population bottleneck in a changing ocean. Global change ecotoxicology is being used to identify the marine invertebrate developmental stages vulnerable to climate change. This overview of research, and the methodologies used, shows that most studies focus on acidification, with few studies on ocean warming, despite a long history of research on developmental thermotolerance. The interactive effects of stressors are poorly studied. Experimental approaches differ among studies. Fertilization in many species exhibits a broad tolerance to warming and/or acidification, although different methodologies confound inter-study comparisons. Early development is susceptible to warming and most calcifying larvae are sensitive to acidification/increased pCO2. In multistressor studies moderate warming diminishes the negative impact of acidification on calcification in some species. Development of non-calcifying larvae appears resilient to near-future ocean change. Although differences in species sensitivities to ocean change stressors undoubtedly reflect different tolerance levels, inconsistent handling of gametes, embryos and larvae probably influences different research outcomes. Due to the integrative ‘developmental domino effect’, life history responses will be influenced by the ontogenetic stage at which experimental incubations are initiated. Exposure to climate change stressors from early development (fertilization where possible) in multistressor experiments is needed to identify ontogenetic sensitivities and this will be facilitated by more consistent methodologies. 相似文献
17.
We examine the concentration variations of the different parameters X of the carbonate system in seawater when calcium carbonate precipitation occurs. Variations are expressed as ∂[X]/∂[Ca2+]. Four different cases are considered: spontaneous chemical precipitation; calcification combined with photosynthetic activity under a constant ΔCT/Δ[Ca2+] ratio; precipitation under constant pCO2 and precipitation under constant [Ca2+]·[CO32−] ionic concentration product. The last condition should be maintained by an ecosystem which, thanks to the regulation of its calcifying and photosynthetic activity, would absorb 1 mol of carbon for organic tissue each time 1 mol of CaCO3 is formed. This stoichiometric ratio would allow the activity of these biological communities to go on in practically closed systems during periods compatible with their growth or development cycles. 相似文献
18.
基于海洋环流模式POP和生物地球化学模型OCMIP-2,建立了全球海洋碳循环模式,并用于对全球海洋碳循环的模拟研究。该模式在大气CO2为283×10-6条件下,积分3 100 a,达到工业革命前的平衡态。在此基础上,用历史时期观测的大气CO2浓度进行强迫,模拟了历史时期的海洋碳循环。模拟的无机碳浓度、总碱度与基于观测得到的结果基本一致,模式能够较好地模拟全球碳循环过程。模拟结果表明,在北半球中高纬度和南半球的中纬度,海洋是大气CO2的主要汇区;在赤道南北纬20°之间和南大洋50°S以南,海洋表现为大气CO2的源区。在1980s海洋吸收CO2速率(以C计)为1.38 Pg/a,1990s为1.55 Pg/a。海洋中人为碳在北大西洋含量最大,向下到达海底并向南输运到30°N附近;在南极附近,浓度较小,深度达到3 000 m;在中纬度,人为碳被限制在温跃层以上。 相似文献
19.
Combined effects of photosynthesis and calcification on the partial pressure of carbon dioxide in seawater 总被引：2，自引：0，他引：2
Atsushi Suzuki 《Journal of Oceanography》1998,54(1):1-7
The effects of marine photosynthesis and calcification on the partial pressure of carbon dioxide in seawater (P
CO
2) are examined in the light of recent studies and using original model calculations. The ratio of organic carbon to inorganic
carbon production (R
OI) determines whether an ecosystem is a net sink or source for atmospheric CO2. TheP
CO
2 maintains its initial value when the photosynthetic rate is approximately 0.6 times the calcification rate under normal sea
surface condition. In case of higherR
OI, theP
CO
2 decreases and seawater can absorb atmospheric CO2. The ratio of organic carbon to inorganic carbon production can be used as a potential indicator of sink-source behavior
in aquatic photo-calcifying systems. 相似文献
20.
Takeshi Yoshimura Koji Suzuki Hiroshi Kiyosawa Tsuneo Ono Hiroshi Hattori Kenshi Kuma Jun Nishioka 《Journal of Oceanography》2013,69(5):601-618
Response of phytoplankton to increasing CO2 in seawater in terms of physiology and ecology is key to predicting changes in marine ecosystems. However, responses of natural plankton communities especially in the open ocean to higher CO2 levels have not been fully examined. We conducted CO2 manipulation experiments in the Bering Sea and the central subarctic Pacific, known as high nutrient and low chlorophyll regions, in summer 2007 to investigate the response of organic matter production in iron-deficient plankton communities to CO2 increases. During the 14-day incubations of surface waters with natural plankton assemblages in microcosms under multiple pCO2 levels, the dynamics of particulate organic carbon (POC) and nitrogen (PN), and dissolved organic carbon (DOC) and phosphorus (DOP) were examined with the plankton community compositions. In the Bering site, net production of POC, PN, and DOP relative to net chlorophyll-a production decreased with increasing pCO2. While net produced POC:PN did not show any CO2-related variations, net produced DOC:DOP increased with increasing pCO2. On the other hand, no apparent trends for these parameters were observed in the Pacific site. The contrasting results observed were probably due to the different plankton community compositions between the two sites, with plankton biomass dominated by large-sized diatoms in the Bering Sea versus ultra-eukaryotes in the Pacific Ocean. We conclude that the quantity and quality of the production of particulate and dissolved organic matter may be altered under future elevated CO2 environments in some iron-deficient ecosystems, while the impacts may be negligible in some systems. 相似文献