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海洋碳循环是全球碳循环的重要组成部分,是影响全球变化的关键控制环节。海洋是地球最大的碳库,是地球吸纳CO2的重要缓冲器。海水中溶解无机碳是海洋CO2系统的重要参数,利用AS-C3型溶解性无机碳分析仪进行不同盐度海水溶解无机碳的测量,利用t检验法检验使用仪器的测量精度,探寻盐度与海水总溶解无机碳的关系。实验结果表明:AS-C3型溶解性无机碳分析仪的测量精度在±0.3μmol/L左右,测量过程中无系统差异;海水盐度与总溶解无机碳呈正相关关系,即盐度增大,海水总溶解无机碳增加。最后总结了海水总溶解无机碳测量时的影响因素,如N2纯度、气流状况、实验过程中的温度控制等。 相似文献
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为了解胶州湾水体和表层沉积物营养环境状况及其主要影响因素,于2019年8月在胶州湾30个站位点采集了海水和表层沉积物样品,并于2021年5月在胶州湾沿岸采集了18个站位点的水样,对水体溶解无机态营养盐浓度和组成以及表层沉积物中总有机碳、总氮、总磷及生物硅含量和碳、氮稳定同位素（δ13C、δ15N）进行了分析。结果表明,胶州湾内水体和沿岸水体中溶解无机氮、溶解无机磷和溶解硅酸盐浓度空间分布相近,高值均位于湾东北部,主要受到河流输入和沿岸污水排放的影响,低值主要出现在湾中部和湾口处。结合近30年来的历史数据分析发现,胶州湾夏季营养盐浓度在1990?2008年期间呈持续上升的趋势,政府实施的污染物总量控制措施以及河流径流量下降使得2006年以来营养盐浓度呈现下降的趋势,该变化在空间上主要体现为大沽河氮、磷输入量的减少及其对应的湾西部营养盐高值的消失。胶州湾氮、磷营养盐输入的不平衡使得“磷限制”在2000年后逐渐加剧。胶州湾表层沉积物中总有机碳、总氮、总磷含量高值均集中于东北部和东部沿岸,结合生物硅和水体营养盐含量分析显示,这主要是河流与排污输入及其带来的高初级生产力造成的,沉积物生源要素与水体营养盐在空间分布上存在较好的耦合关系。沉积物粒度较粗对有机质保存的不利影响以及湾口较强的水动力作用共同导致了湾西部、中部以及湾口的生源要素含量较低。δ13C以及二端元混合模型显示,胶州湾表层沉积物有机质来源总体以海源为主,平均占比为64%,东部沿岸受陆源输入影响较明显。δ15N的空间分布显示,胶州湾表层沉积物中氮元素受到了海水养殖与污水排放的共同影响。水体和沉积物营养环境现状共同表明,对东北部河流和沿岸污水排放的控制是后期胶州湾污染治理的关键。 相似文献
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大型海藻组织碳、氮含量及δ15N值的变化对于指示营养盐来源及营养盐评价研究具有重要的意义。为探究大型海藻组织碳、氮含量及δ15N值的变化特征,于2020年7月至2021年6月逐月分析了小长山岛潮间带孔石莼（Ulva pertusa）、角叉菜（Chondrus ocellatus）、鼠尾藻（Sargassum thunbergii）3种大型海藻组织的碳、氮含量和δ15N值的变化,并对其生长环境中海水的理化因子进行了测定。结果发现：孔石莼组织的氮含量与海水中的NO3-N和DIN含量之间存在显著的相关性,角叉菜组织的氮含量与海水中的NH3-N含量之间也存在显著的相关性。然而,大型海藻组织的碳含量和C/N比值与海水中的碳、氮营养盐之间并无显著的相关性。孔石莼组织的δ15N值与海水中的NO3-N和DIN含量之间也存在显著的相关性。因此,孔石莼适于用作NO3-N和DIN来源的指示藻种。结果指示小长山岛潮间带海水中具有供大型海藻生长利用的充足的营养盐,其主要受到生活污水和养殖排放的影响。 相似文献
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模拟添加氮对海水溶解无机碳体系的影响 总被引：1，自引：0，他引：1
碳和氮作为主要的生源要素对维持海洋生态系的正常运转起着至关重要的作用,碳与氮的变化是相互耦合的且呈双向作用,为探讨海水无机碳与氮的相互作用规律,研究了室内模拟添加硝酸盐对海水无机碳体系pH、溶解无机碳(DIC)、HCO3-、二氧化碳分压(Pco2)的影响。结果表明,在室内培养的条件下,单纯添加硝酸盐(增加至原海水硝酸盐浓度的5-20倍)可引起培养体系浮游生物量的变化,但不能引起海水pH及DIC、HCO-3含量的明显变化,对DIC而言,其变化率仅仅在1%以内,但可导致海水Pco2的相对明显升高,其最终结果导致海水碳汇强度的减弱,碳源强度的增加。 相似文献
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海水中的N,P,Si是海洋中最基本的营养物质,对海洋浮游生物的生存、繁殖、海洋生物食物链结构和新陈代谢,以及海洋中物质的循环都具有重要的意义,一直是海洋学研究的重要内容之一,几乎世界上海洋的各个区域都有其研究报道。中国陆架海中营养物质的研究已进行了40多年,获得了大量的资料和重要的研究成果。随着我国海洋科学的发展,近年来陆续开展了世界大洋、极地海的营养盐研究,并有一些报道(顾宏堪,1992;宋金明,1995,1996; Hecky等,1993),但对世界大洋定点长周期的营养盐变化观测研究和降水对表层海水的输入影响长周期定点系列观测还未见报道。热带西太平洋海域有一个世界海洋中最大的高温、高盐“暖池(WPWP)”,这里进行着地球上强烈的海气相互作用,所以,研究该海域海水中营养盐的变化规律,对系统研究海洋对气候的调节作用,乃至全球气候变化都具有重要意义。本文通过对4°S,156°E长达4个月的定点观测,研究了上层海水、深水中营养盐的变化、营养盐的周日变化及降水对表层海水营养盐输人的影响,本文为TOGA-COARE研究的一部分。 相似文献
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海洋沉积物中稀土元素的分布、转移行为已有许多报道。地球环境中稀土元素的行为是当今地学研究的热门课题,稀土元素的分布特性和转移行为研究与环境有极大的相关性,通过研究环境中稀土元素的转移行为就可了解环境演变的信息,所以海洋环境中稀土元素的研究具有重要的意义(Fleet,1984; Piper,1974; Schijf et al.1995;赵一阳等,1994;王中刚等,1989;张丽洁等,1995)。海洋中颗粒物质垂直转移过程研究对研究海洋在全球变化(特别是全球气候变化)中有重要意义,但目前的研究仅集中于以碳为核心的生源要素和某些微量元素(宋金明等,1996;宋金明,1997),至今稀土元素在海水中垂直转移过程研究尚未见报道。珊瑚礁生态系是最重要的海洋生态系之一,研究珊瑚礁生态系中稀土元素的垂直通量,即热带海域稀土元素在海水中垂直转移过程,继而椎测对全球气候变化的影响,为研究海洋在全球气候变化中的作用提供了新课题。
本文首次报道用沉积物捕捉器(ST)收集南沙珊瑚礁潟湖中颗粒物质,研究稀土元素的垂直通量和不同形态稀土的垂直通量,以及稀土元素垂直转移的控制因素。 相似文献
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海洋围隔生态系中营养盐和重金属对浮游生物的影响 总被引：1，自引：2，他引：1
多年来北美、欧洲、日本和澳大利亚的海洋生态学家和海洋生物地球化学家广泛应用海洋围隔生态系研究营养盐浓度和通量的变化与有关的化学和生物学过程之间的关系.例如,H.S.Peter(1982)系统综述了营养盐的地球化学循环[1].Isao Koike和AkihikoHattori等人(1982)利用CEPEX详尽探讨沿岸水氮的动力学[2].K.Kremling等人(1978)论述了在围隔实验生态系中营养盐的变化和用镉处理的生态系对海洋浮游植物生长的影响[3].还有W.H.Thomas用等人(1977)评价了1976年在加拿大不列颠哥伦比亚萨阿尼奇湾的受控生态系污染实验中汞对海洋浮游植物群落的影响[4]. 相似文献
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海藻营养代谢研究进展——海藻营养代谢的调节 总被引：3，自引：1，他引：3
介绍影响海藻 (尤其是大型海藻 )主要营养盐 ( N,P,C)吸收的环境因子 (如光照、温度及水流 )对营养盐主动吸收过程中的能量提供 ,酶含量和活性的影响以及水流对藻体周围营养盐离子进入细胞的调节 ;化学因素 (营养盐离子或分子的浓度、形式、海水介质的 p H)对海藻选择吸收不同形式营养盐离子及其相互作用的调节过程 ;生物因素 (藻体形态、组织的类型及海藻的年龄和营养史 )通过细胞内不同水平营养库的积累和相互转变而对海藻营养吸收和同化的调节 ;N代谢与 C代谢的生化偶连关系。 相似文献
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介绍影响海藻(尤其是大型海藻)主要营养盐(N,P,C)吸收的环境因子(如光照、温度及水流)对营养盐主动吸收过程中的能量提供，酶含量和活性的影响以及水流对藻体周围营养盐离子进入细胞的调节；化学因素(营养盐离子或分子的浓度、形式、海水介质的pH)对海藻选择吸收不同形式营养盐离子及其相互作用的调节过程；生物因素(藻体形态、组织的类型及海藻的年龄和营养史)通过细胞内不同水平营养库的积累和相互转变而对海藻营养吸收和同化的调节；N代谢与C代谢的生化偶连关系。 相似文献
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Song Jinming 《海洋学报(英文版)》2003,22(1):57-68
Carbon cycle is connected with the most important environmental issue of Global Change.As one of the major carbon reservoirs, oceans play an important part in the carbon cycle. In recent years, iron seems to give us a good news that oceanic iron fertilization could stimulate biological productivity as CO2 sink of human-produced CO2. Oceanic iron fertilization experiments have verified that adding iron into high nutrient low chlorophyll (HNLC) seawaters can increase phytoplankton production and export organic carbon, and hence increase carbon sink of anthropogenic CO2, to reduce global warming. In sixty days, the export organic carbon could reach 10 000 times for adding iron by model prediction and in situ experiment, i.e. the atmospheric CO2 uptake and inorganic carbon drawdown in upper seawaters also have the same magnitude. Therefore, oceanic iron fertilization is one of the strategies for increasing carbon sink of anthropogenic CO2. The paper is focused on the iron fertilization, especially in situ o 相似文献
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Enhancement/reduction of biological pump depends on ocean circulation in the sea-ice reduction regions of the Arctic Ocean 总被引：1，自引：0，他引：1
Shigeto Nishino Takashi Kikuchi Michiyo Yamamoto-Kawai Yusuke Kawaguchi Toru Hirawake Motoyo Itoh 《Journal of Oceanography》2011,67(3):305-314
The biological pump is a central process in the ocean carbon cycle, and is a key factor controlling atmospheric carbon dioxide
(CO2). However, whether the Arctic biological pump is enhanced or reduced by the recent loss of sea ice is still unclear. We examined
if the effect was dependent on ocean circulation. Melting of sea ice can both enhance and reduce the biological pump in the
Arctic Ocean, depending on ocean circulation. The biological pump is reduced within the Beaufort Gyre in the Canada Basin
because freshwater accumulation within the gyre limits nutrient supply from deep layers and shelves hence inhibits the growth
of large-bodied phytoplankton. Conversely, the biological pump is enhanced outside the Beaufort Gyre in the western Arctic
Ocean because of nutrient supply from shelves and greater light penetration, enhancing photosynthesis, caused by the sea ice
loss. The biological pump could also be enhanced by sea ice loss in the Eurasian Basin, where uplifted isohaline surfaces
associated with the Transpolar Drift supply nutrients upwards from deep layers. New data on nitrate uptake rates are consistent
with the pattern of enhancement and reduction of the Arctic biological pump. Our estimates indicate that the enhanced biological
pump can be as large as that in other oceans when the sea ice disappears. Contrary to a recent conclusion based on data from
the Canada Basin alone, our study suggests that the biological CO2 drawdown is important for the Arctic Ocean carbon sink under ice-free conditions. 相似文献
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渤海海峡冬季表层海水中溶解无机碳分布特征分析 总被引：1，自引：0，他引：1
根据2010 年2 月—2010 年3 月的调查数据, 探讨了冬季渤海海峡及其附近表层海水中溶解无机碳体系的分布特征。结果表明: 表层水体中TA、DIC 和HCO3- 的浓度分布总体上呈现出海峡西南部高东北部低的分布趋势。西南部出现的高值区, 与该区域靠近莱州湾, 受莱州湾水体污染影响有关。调查海域TA 与表层水的温度相关性明显, pH 与叶绿素的相关性较高。水温和Chl-a 浓度是影响水体中无机碳体系分布变化的重要因素。其中, 水温对HCO3- 的影响要明显强于DIC。海峡南北两侧水体交换的差异, 是导致海峡南部东西两端无机碳体系各参数监测数值的差异明显大于海峡北部的主要原因。 相似文献
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Historical simulation and twenty-first century prediction of oceanic CO2 sink and pH change 总被引：1，自引：1，他引：0
A global ocean carbon cycle model based on the ocean general circulation model POP and the improved biogeochemical model OCMIP-2 is employed to simulate carbon cycle processes under the historically observed atmospheric CO 2 concentration and different future scenarios (called Rep- resentative Concentration Pathways, or RCPs). The RCPs in this paper follow the design of Inter- governmental Panel on Climate Change (IPCC) for the Fifth Assessment Report (AR5). The model results show that the ocean absorbs CO 2 from atmosphere and the absorbability will continue in the 21st century under the four RCPs. The net air-sea CO 2 flux increased during the historical time and reached 1.87 Pg/a (calculated by carbon) in 2005; however, it would reach peak and then decrease in the 21st century. The ocean absorbs CO 2 mainly in the mid latitude, and releases CO 2 in the equator area. However, in the Antarctic Circumpolar Current (ACC) area the ocean would change from source to sink under the rising CO 2 concentration, including RCP4.5, RCP6.0, and RCP8.5. In 2100, the anthropogenic carbon would be transported to the 40 S in the Atlantic Ocean by the North Atlantic Deep Water (NADW), and also be transported to the north by the Antarctic Bottom Water (AABW) along the Antarctic continent in the Atlantic and Pacific oceans. The ocean pH value is also simulated by the model. The pH decreased by 0.1 after the industrial revolution, and would continue to decrease in the 21st century. For the highest concentration sce- nario of RCP8.5, the global averaged pH would decrease by 0.43 to reach 7.73 due to the absorption of CO 2 from atmosphere. 相似文献
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Alan G. Judd 《Geo-Marine Letters》2003,23(3-4):147-154
Seabed fluid flow includes volcanic and hydrothermal fluid emissions from ocean spreading centres, island arcs, and intra-plate volcanism, and groundwater flows in some coastal areas. Of direct concern to this paper is the escape of methane from the seabed. Escaping methane may be of microbial, thermogenic or abiogenic origin. Escapes occur in all seas and oceans, in coastal waters, on continental shelves, slopes and rises, the deep oceans, and deep ocean trenches. These represent a variety of geological contexts on passive continental margins, at convergent plate margins (accretionary wedges) and transform plate boundaries. Seepage is clearly widespread, and it contributes methane to the biosphere, the hydrosphere and the atmosphere, thus making up an important part of the global carbon cycle. 相似文献
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自然资源部第一海洋研究所地球系统模式FIO-ESM是自主研发的、以耦合海浪模式为特色的地球系统模式,包括物理气候模式和全球碳循环模式。该模式从第一代版本FIO-ESM v1.0发展到第二代版本FIO-ESM v2.0,其物理气候模式和全球碳循环模式都取得了改进与提升。FIO-ESM v2.0全球碳循环模式的海洋碳循环模式由v1.0的营养盐驱动模型升级为NPZD（Nutrient-Phytoplankton-Zooplankton-Detritus）型的海洋生态动力学碳循环模型,陆地碳循环模型由v1.0的简单的光能利用率模型升级为考虑碳氮相互作用的碳氮（CN）耦合模型;大气碳循环模型仍为CO2的传输过程,考虑了化石燃料排放、土地利用排放等人为CO2排放量。在物理过程参数化方案方面,FIO-ESM v2.0全球碳循环过程在考虑浪致混合作用对生物地球化学参数的作用的基础上,增加了海表面温度的日变化过程对海-气CO2通量的影响。已有数值模拟试验结果表明,FIO-ESM v2.0在考虑了更加复杂的碳循环过程后仍具有较好的全球碳循环模拟能力,为进一步开展海洋与全球碳循环研究提供了更有力的支撑工具,从而更好地服务于国家的双碳目标。 相似文献
18.
The practical (Sp) and reference (SR) salinities do not account for variations in physical properties such as density and enthalpy. Trace and minor components of seawater, such as nutrients or inorganic carbon affect these properties. This limitation has been recognized and several studies have been made to estimate the effect of these compositional changes on the conductivity–density relationship. These studies have been limited in number and geographic scope. Here, we combine the measurements of previous studies with new measurements for a total of 2857 conductivity–density measurements, covering all of the world׳s major oceans, to derive empirical equations for the effect of silica and total alkalinity on the density and absolute salinity of the global oceans and to recommend an equation applicable to most of the world׳s oceans. The potential impact on salinity as a result of uptake of anthropogenic CO2 is also discussed. 相似文献
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Biological Pump in Northwestern North Pacific 总被引：1，自引：1，他引：1
Makio C. Honda 《Journal of Oceanography》2003,59(5):671-684
The northwestern North Pacific is considered to be one of the most productive areas in the global ocean. Although the marginal
zones along the Japanese and Kuril islands, Kamchatka Peninsula, and Aleutian Islands are certainly productive, recent studies
do not always show high primary production values in the western subarctic gyre (WSG). In addition, a recent analysis of the
biological pump in the WSG showed that, in contrast to what was previously reported, the vertical change of the particulate
organic carbon flux with depth is large. Nevertheless, the biological pump in the northwestern North Pacific may function
to draw down the partial pressure of CO2 in the surface water because the ratio of the organic carbon flux to inorganic carbon flux (Corg/Cinorg), the export flux, and the export ratio from the surface water are higher than those in other oceans. This article also introduces
recent research on changes to the biological pump that might have been caused by global warming.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献