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1.
大洋海山及其生态环境特征研究进展 总被引：1，自引：0，他引：1
海山作为深海大洋独特地貌,尽管其研究可追溯到100多年前,但对大洋海山的形成、地质特征、动力学特性、生态环境等方面了解甚少。随着人们认识海洋程度的提升,特别是回声探测、无人潜水器和卫星技术等技术的应用,对大洋海山的系统探索已取得了前所未有的进展,大洋海山研究已成为当代人们所渴求探索的领域之一。本文对大洋海山的研究历程、分类、生物群落特征、水文环境特征以及维持海山区高生物量的机制进行了总结。目前全球海山主要有两种分类方式,其分类一是基于构造特征,可将海山分为板块内海山、大洋中脊海山和岛弧海山;二是基于山顶到海表面的距离,可将海山分为浅海山、中等深度海山和深海山。海山为生物提供了独特的栖息地,形成了高生物量、高生物多样性和高生物独有性等三种主要的生物群落特征,使海山成为世界海洋渔业的重点海域和生态环境研究的热点区域之一。海山突出的地形对大洋环流造成阻隔,因而在海山周围形成了其独特的水文环境,其中海山环流和上升流是其两种典型代表,这些独特的水文环境特征对生物群落的组成和分布具有重要影响。海山区的高生物量主要通过上升流输送、地形诱捕和海流水平输送三种机制维持,三种机制对支撑海山生态系统的物质循环和能量流动至关重要。 相似文献
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2014年冬季对西太平洋雅浦Y3海山区和从西太平洋暖池区到黑潮源区之间的大洋海域的浮游动物进行了调查研究，分析了海山区和大洋海域大型浮游动物群落的物种组成、丰度和分布，并比较了两个海域大型浮游动物群落的差异，结合温度、盐度和叶绿素a浓度等环境因子数据，分析了海山对大型浮游动物群落的影响。结果表明，Y3海山区和大洋海域的大型浮游动物群落物种组成存在差异，二者的群落相似度系数为68.4%，两个海域的优势种/类群也不尽相同，海山区的优势种/类群是磷虾各期幼体、尖额磷虾和蛮𧊕，而大洋海域的优势种/类群分别是磷虾后期幼体、手磷虾、蛮𧊕、尖额磷虾和莹虾。大型浮游动物群落在海山区的平均丰度和最大丰度都要高于大洋海域，但海山区的生物多样性指数、均匀度指数和生物量占比都低于大洋海域，因而Y3海山对大型浮游动物群落的海山效应不明显。通过相关性分析和主成分分析结果可以看出，海山区的首要影响环境因子是盐度，而大洋海域则是温度；海山区和大洋海域的大型浮游动物丰度分别与200m层盐度和平均温度呈负相关关系，并且在两个调查海域均未发现大型浮游动物的丰度和生物量分布与叶绿素a浓度之间存在显著的相关关系。 相似文献
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海山可以通过与洋流的相互作用改变水体结构,促进悬浮体以及海洋生物的再分配,进而影响海洋生物地球化学过程,促进大洋物质和能量交换。西太平洋有着复杂的环流结构,也是海山分布最多的海区之一。为研究西太平洋海山区的悬浮体分布及其控制机制,2017年夏季在西太平洋卡罗琳M4海山区进行现场调查,利用扫描电镜分析了该海山区悬浮体样品的物质组成及分布,并结合温度、盐度和荧光叶绿素a浓度数据,讨论了海山对悬浮体分布的影响。结果表明,M4海山区的悬浮体由生物碎屑、矿物颗粒和絮凝体等组成。海水的强烈层化阻碍了该海山区下层营养物质的上涌,使上层水体呈现出寡营养的特征,导致大部分站位悬浮体丰度较低;但在海山顶部,潮流和海山地形相互作用在山顶上方形成反气旋环流,不仅促进了深水的营养物质向上扩散,使得荧光叶绿素a浓度升高,同时对平流输送来的以及从深水中上涌的悬浮体起到了滞留作用,使山顶上方的悬浮体丰度远高于离山顶较远的位置。随着水深的增大,温、盐跃层的强度减弱,水体中的营养盐浓度升高,为浮游生物的生长提供了适宜的环境,进而使生物碎屑及絮凝体的丰度升高。北赤道潜流挟带来自西太平洋近岸海区的陆源矿物颗粒到达M4海山区,... 相似文献
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研究了热带西太平洋雅浦Y3海山冬季和马里亚纳M2海山春季网采浮游植物群落结构,对调查区浮游植物的物种组成、优势种类、细胞丰度以及多样性指数进行了分析。结果表明,两个海山区共鉴定浮游植物4门50属219种,其中硅藻门30属106种,甲藻门17属112种,蓝藻门1属2种,金藻门2属3种。两个航次研究区浮游植物优势种均以链状硅藻如根管藻(Rhizosolenia)、半管藻(Hemiaulus)和角毛藻(Chaetoceros)等属的种类为主,此外太阳漂流藻(Planktoniella sol)、铁氏束毛藻(Trichodesmium thiebautii)以及部分角藻(Ceratium)物种优势度也比较明显。Y3海山区浮游植物细胞丰度介于1.60～16.61 cells/L,平均值为5.02 cells/L; M2海山区浮游植物细胞丰度介于1.36～10.20 cells/L,平均值为4.12cells/L。两个海山区浮游植物细胞丰度的分布趋势均受硅藻影响较大,甲藻细胞丰度相对较低。在属的水平上,角毛藻、根管藻、角藻和半管藻等属的细胞丰度对两个海山区浮游植物总细胞丰度的贡献较大。多样性指数方面, Y3海山区浮游植物群落香农-威纳指数H′(shannon-wiener index)介于3.95～4.69,平均值为4.30; M2海山区浮游植物群落香农-威纳指数介于3.23～4.46,平均值为3.83。两个海山区浮游植物群落多样性指数均处于较高水平,但站位间的变化不明显。目前,关于热带西太平洋海山区浮游植物群落结构的研究还非常缺乏,亟需后续研究的补充。 相似文献
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武汉东湖不同湖区浮游甲壳动物群落结构的比较 总被引：6，自引：0，他引：6
对武汉东湖 4个不同营养水平和不同滤食性鱼类密度的湖区 1 993— 1 998年期间的浮游甲壳动物群落结构进行了比较研究。结果表明 ,营养水平及滤食性鱼类的密度以Ⅰ、Ⅱ、Ⅲ、Ⅳ站的次序依次下降 ;各站间浮游甲壳动物总生物量及各类群 (枝角类、剑水蚤和哲水蚤 )的生物量差异较大 ,并且哲水蚤相对于剑水蚤的优势度以Ⅰ、Ⅱ、Ⅲ、Ⅳ站的次序上升。浮游甲壳动物优势种结构在Ⅰ、Ⅱ站与Ⅲ、Ⅳ站间的差异尤为明显 :近邻剑水蚤与微型裸腹生物量在营养水平及鱼类生物量高的Ⅰ、Ⅱ站显著较高 ,而盔型透明的生物量在营养水平及鱼类生物量较低的Ⅲ站显著较高 ,表明水体的营养水平及滤食性鱼类的捕食压力是导致浮游甲壳动物群落在东湖不同湖区具有不同分布格局的重要因素 相似文献
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长江口邻近海域大型底栖生物群落结构分析 总被引：10，自引：0，他引：10
2004年5月的调查共获大型底栖生物50种,种数和丰度的优势生物为多毛类动物,而底栖鱼类和螠虫的生物量占明显优势。长江口大型底栖生物平均生物量为17.57g/m2,平均丰度为150ind./m2。生物量和丰度密集区集中在盐度25度线附近海域。根据Bray-Curtis相似性系数聚类分析和多维排序尺度分析,长江口大型底栖生物可划分为四个群落:Ⅰ圆筒原盒螺-滩栖阳遂足-棘刺锚参-背蚓虫群落;Ⅱ圆筒原盒螺-钩虾群落;Ⅲ背蚓虫-奇异稚齿虫-不倒翁-尖叶长手沙蚕-近辐蛇尾群落;Ⅳ短叶索沙蚕-长吻沙蚕-纽虫群落。通过引入环境变量的二维MDS图分析,长江口大型底栖生物群落分布与底层盐度、有机物具有较大的相关性。生存环境短时间内的剧烈变化是导致群落Ⅱ和Ⅳ种群贫乏的重要原因之一。河口区悬浮粉砂颗粒的短期快速沉降现象可能也是导致群落Ⅱ和Ⅳ种群贫乏的另一重要原因。 相似文献
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断裂和白垩纪岩浆活动对中西太平洋海山区海山形成的影响 总被引：6，自引：0，他引：6
断裂和岩浆活动影响着海山的形成及其基岩的分布类型。在总结中、西太平洋海山区的海山与构造分布特征、白垩纪大规模岩浆喷发事件、海山形成年代分布、海山与海底高原的岩性分布和GEOROC数据库样品的年代时序对比的基础上,分析了断裂和白垩纪岩浆活动的特点及其对中、西太平洋海山区海山形成的影响作用。研究认为:中、西太平洋海山区的洋壳在海山形成前受断裂带改造;受白垩纪大规模岩浆活动的影响,中、西太平洋海山区的海山约在87~89 Ma和120~123 Ma出现两个生长高峰期,并且在岩性上表现出与同期生成的海底高原相近。 相似文献
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对北海鱼类营养级和生物量进行了综合分析,北海鱼类群落中,浮游生物食性、底栖生物食性和游泳生物食性鱼类的平均营养级分别为3.5,3.9和4.5,依次递增,而它们的生物量之比为1∶0.8∶0.4,依次递减,由此发现了一种与生物量锥体相似而又不同的现象,即捕食者与捕食者之间横向的营养级与生物量的负相关关系,作者称之为类生物量锥体。北海的生物量锥体其底部与顶部营养级之比为1∶4,生物量之比为1333∶1;类生物量锥体其底部与顶部营养级之比为3.5∶4.5,生物量之比只有2.36∶1,由此看出类生物量锥体相似于生物量锥体,但又不同于Odum提出的被食者与捕食者之间的纵向关系的生物量锥体,其生物量的变化幅度较生物量锥体为小。类生物量锥体的意义在于可以从鱼类生态类群营养级的高低来推测其生物量的状况。 相似文献
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尖顶海山和平顶海山是洋底海山的两种类型,同时也是富钴结壳资源赖以成长的主要载体,两者在地形上具有显著差别,资源状况和分布也不尽一致。以地形分类为基础,就中太平洋海山区两类海山结壳的成矿特征、宏微观构造、矿物和化学组成以及空间分布等进行了比对研究。研究认为,尖顶海山体积虽小,但地形演化连续,底层流及环境氧化性较强,有利于结壳的长期稳定生长,结壳厚度总体较大,富成矿元素和生物组分,远景成矿区域连续绵长。平顶海山山体巨大,顶部和斜坡陡崖区不利于结壳成长,底流活动只在山顶边缘和山脊地带表现突出,环境氧化性整体较弱,后期构造活动相对频繁,结壳总体厚度较小,铁,碎屑和热液组分含量较高,远景矿区相对狭窄。 相似文献
10.
椒南化工区排污口附近海域的底栖生物状况 总被引：1，自引：1，他引：0
利用2002年6～7月椒南化工区排污口附近海域生态调查资料,对该海域底栖生物的种类组成、数量分布及其生态群落多样性等进行了分析和研究,结果表明:(1)该海域底栖生物种类贫乏,多毛类Polychaeta、海地瓜Acaudinamolpadioidea及纵肋织纹螺Nassariusvari-ciferus等耐污种类为优势种;(2)该海域底栖生物生物量较低,且局部海域出现了无底栖生物现象;(3)该海域底栖生物多样性指数低、丰富度低、优势度大,表明底栖生物的生态环境已受到严重污染。 相似文献
11.
《Deep Sea Research Part II: Topical Studies in Oceanography》2009,56(25):2618-2630
The temporal and spatial variability in the water-column distribution of dissolved organic carbon (DOC), and the particulate organic matter, collected both with bottles (POM-b) and in situ pumps (POM-p), was studied around Sedlo and Seine, two seamounts located in subtropical waters of the northeast Atlantic Ocean. Seine and Sedlo presented high POM-b concentrations, compared with reported background concentrations from the Azores-Madeira region, although our results show large regional, temporal and intra-seamount variability around the two seamounts. On the contrary, the POM-p pool, which contributed only 25–56% of the POC-b at surface, represented a fairly constant fraction of the suspended POM. Seine was characterized by higher POC-b concentrations than Sedlo, presumably as result of a combined mechanism of advection from the far field, and retention/accumulation of organic carbon, favoured by the secondary circulation around the seamount. Passive accumulation of POM-b was also evident at the southern flank of Sedlo during one the surveys, coinciding with a change in the local circulation around the seamount caused by the intrusion of a Mediterranean water eddy (Meddy). Average PON concentrations at the two seamounts were comparable in magnitude, and hence the C/N ratios were higher in Seine, adding support to the hypothesis of advection of allochtonous highly refractory organic matter into Seine. The contribution of DOC to the apparent oxygen utilization (AOU) in the upper 1000 m was significantly higher in Seine (25%) than in Sedlo (11%). This points to a proportionally more important role of dissolved material to the overall carbon remineralization rates in the water column of Seine. 相似文献
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《Deep Sea Research Part II: Topical Studies in Oceanography》2009,56(25):2646-2655
We have studied the epipelagic (0–100 m) metabolic balance between gross and net community production (Pg, Pn) and community respiration (Rd) around two seamounts (Seine: 34°N, 14°W; Sedlo: 40°N, 27°W) located in the subtropical northeast Atlantic. We looked for local effects causing seamounts to increase community production and/or community respiration with respect to the surrounding open ocean. Comparatively, Seine presented similar average living plankton biomass—chlorophyll a (Chl) and particulate proteins (Pt)—but higher Pg, due to higher Rd, presumably the result of organic matter loading from the NW Africa upwelling system, as supported by field results and satellite imagery. Nevertheless, the large temporal and spatial variability at each seamount make the average differences non-significant. Temporal variability in P, Rd and Chl was evident around the two seamounts. Sedlo showed higher Rd, Chl and Pt during winter, but higher Pn in summer. Seine presented higher Pt, Chl and Pn during spring, but higher Rd in summer. On average, the metabolic balance was heterotrophic (Rd>Pg) during all the sampling periods and at most stations of the two seamounts. Both Sedlo and Seine, showed higher Rd with respect to average values reported for the global ocean. A clear seamount effect on phytoplankton was only observed in Seine during spring, when Chl and Pt were enhanced at the summit of the seamount. Our results suggest that, rather than increasing primary production significantly, the two seamounts could act as trapping mechanisms for organic matter, favoured by the development of Taylor Columns on the top of the seamounts. Nevertheless these effects seem to be of a lower magnitude than changes caused by temporal or regional variability, questioning the role of these seamounts as hot-spots of productivity in the oceans. 相似文献
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《Deep Sea Research Part II: Topical Studies in Oceanography》2009,56(25):2631-2645
The suspended particulate organic matter (sPOM) around two isolated NE Atlantic seamounts, Seine (33°46′N 14°21′W; summit at ∼170 m) and Sedlo (40°19′N 26°40′W; summit at ∼780 m), was studied over a period of 2 years during four 2–4-week oceanographic surveys. Elemental (C and N), chlorophyll a and lipid biomarker concentrations and N stable isotopic values were variable close to the surface (40–90 m), although some chlorophyll a enrichment above the summits was discerned sporadically. Results from near-surface waters showed a generally “fresh”, mainly phytoplankton signature in sPOM with some seasonality, which was more pronounced around Sedlo. sPOM concentrations and composition changed with depth, apparently controlled by seasonality and proximity to the seamounts. A few metres above the Seine summit, the suspended particulate organic carbon (sPOC) concentrations and labile polyunsaturated fatty acids (% of lipids) were higher than elsewhere at similar depths (∼200 m) in summer 2004. In the same season at Sedlo, polyunsaturated fatty acids were also relatively more abundant (up to 43% of total lipids) around the topographic feature throughout the water column, indicating supply of more labile sPOM, perhaps by advection, downwelling or passive sinking of locally produced phytoplankton and/or in situ production. The high-quality sPOM that seems to be present around the seamounts could provide an important food source to the biological community. 相似文献
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崂山湾潮间带食物网结构的碳稳定同位素初步研究 总被引：14，自引：3，他引：14
通过对1993年8月和1994年2和5月在崂山湾潮间带采集的底栖生物碳稳定同位素组成(δ13C值)的分析,发现该区底栖动物的主要食物来源以δ13C值大致可划分为4类:水体中的颗粒有机质(POM)、底栖硅藻、大型底栖藻类和底泥中的有机物质(SOM).研究结果表明,底栖动物的碳稳定同位素组成与其所摄食的食物的碳稳定同位素组成有密切的关系,因此,底栖动物的碳稳定同位素组成可以用于研究其食物来源.碳稳定同位素数据证实,双壳类等滤食性动物的食物来源主要是POM;甲壳动物的δ13C值的范围较大,证明其食物来源的多样性;底栖硅藻是多数腹足类食物来源的相当重要组成部分.用碳稳定同位素示踪剂对该区底栖-水体耦合作用的初步研究表明,水体中的POM是底栖动物的重要食物来源,但底泥中有机质和底栖硅藻也是许多底栖动物食物来源的相当重要的组成部分. 相似文献
17.
By analyses of carbon isotopic composition(δ13C values) of the benthos collected in the Laoshan Bay in August 1993 and February and May 1994, it is found that the main food sources of the benthos can be divided into four groups in terms of carbon isotope composition: Particulate Organic Matter (POM),benthic diatoms, benthic macroalgae and the organic matter in sediments.The results show that the carbon isotopic composition of the benthic animals has a close relation with that of the food they take in.The carbon isotopic compositions of benthos may be useful in elucidating their food sources.The carbon isotopic data have confirmed that POM is the main food source of the benthic filter feeders such as bivalves; crustaceans have a wide range of δ13C values, showing their food source has diversity; benthic diatoms are an important fraction of the food for most of gastropods.A preliminary investigation of the benthic-pelagic coupling in that region using the stable carbon isotopic tracers has confirmed the importance of POM as a food source for benthos in this region,but the organic matter in sediments and benthic diatoms are also relatively important for a lot of benthic animals.The benthic-pelagic coupling in the Laoshan Bay temperate ecosystem is not so tight as that in ecosystems at higher latitudes such as north-eastern water polynya. 相似文献
18.
Xiuwu Sun Jinmin Chen Baohong Chen Cai Lin Yang Liu Jiang Huang Zhong Pan Kaiwen Zhou Qing He Fangfang Kuang Hui Lin 《海洋学报(英文版)》2022,41(11):34-44
The flux of settling particles in the ocean has been widely explored since 1980s due to its important role in biogenic elements cycling, especially in the transport of particulate organic carbon (POC) in the deep sea. However, research in the seamount area of the oligotrophic subtropical Northwest Pacific Ocean is lacking. In this work, two sediment traps were deployed at the foot and another two at the hillside of Niulang Guyot from August 2017 to July 2018. The magnitude and composition of particle fluxes were measured. The main factors influencing the spatial variations of the fluxes were evaluated. Our results indicated a low particulate flux from Niulang Guyot area in the Northwest Pacific Ocean, reflecting low primary productivity of the oligotrophic ocean. The total mass flux (TMF) decreased from 2.57 g/(m2·a) to 0.56 g/(m2·a) with increasing depth from 600 m to 4 850 m. A clear seasonal pattern of TMF was observed, with higher flux in summer than that in winter. The peak flux of 26.52 mg/(m2·d) occurred in August at 600 m, while the lowest value of 0.07 mg/(m2·d) was shown in February at 4 850 m. The settling particles at the deep layers had similar biochemical composition, with calcium carbonate (CaCO3) accounting for up to 90%, followed by organic matter and opal, characteristics of Carbonate Ocean. The POC flux decreased more rapidly in the twilight layer because of faster decomposition, remineralization, and higher temperature. A small fraction of POC was transported into the deep ocean by biological pump. Particle fluxes were mainly controlled by the calcareous ballasts besides the primary productivity of the surface water. The advection may be another important factor affecting the flux in the seamount area. The combination of settled matters rich in foraminiferal tests with topography and currents may be the reason for regulating the local abundance of benthos on seamounts. Our results will fill in the knowledge gap of sedimentation flux, improve the understanding of ecosystem in Niulang Guyot area, and eventually provide data support for the optimization of regional ecological modeling. 相似文献