黄海浮游动物功能群的研究

IOCAS-IR > 海洋环流与波动重点实验室

	黄海浮游动物功能群的研究
其他题名	Study on the zooplankton functional groups in the Yellow Sea
	霍元子
学位类型	博士
	2008-06-05
学位授予单位	中国科学院海洋研究所
学位授予地点	海洋研究所
关键词	黄海浮游动物功能群
摘要	浮游动物在海洋生态系统物质循环和能量流动中起着至关重要的作用。浮游动物物种组成、生物量和次级生产力的变化会改变生态系统的结构和功能。在黄海生态系统中如何描述这个过程，并使它易于模拟是本论文的研究目的。生物量和生产力是海洋生态系统食物网的基础。谁是浮游动物生物量和次级生产力的基础？哪些种类在生态系统中起关键作用？这些问题在黄海这样的温带陆架边缘海区很难回答，原因是物种组成、生物量和生产力的季节变化显著。因此，在对黄海食物产出的关键过程进行模拟时，需要应用既准确又简便的方法来对浮游动物群落的生态过程进行模拟。在对黄海浮游动物群落结构和物理海洋学特征进行充分的分析之后，浮游动物功能群的方法被确定用来进行黄海生态系统结构和功能的模拟。根据浮游动物的粒径、摄食习性和营养功能，黄海浮游动物被分为6个功能群：大型浮游甲壳动物功能群（Giant crustacean，GC）、大型桡足类功能群（Large copepods, LC）、小型桡足类功能群（Small copepods，SC）、毛颚类功能群（Chaetognaths）、水母类功能群（Medusae）和海樽类功能群（Salps）。GC、LC和SC是按照粒径大小而划分的功能群，他们是高营养层次的主要食物资源。毛颚类和水母类是两类胶质性的肉食性浮游动物功能群，他们与高营养层次竞争摄食饵料浮游动物；海樽类与其他浮游动物种类竞争摄食浮游植物，而本身的物质和能量却不能有效的传递到高营养层次。本文研究报道了浮游动物各功能群的时空分布、基于浮游动物动能群的黄海生态区划分、饵料浮游动物功能群的生产力、毛颚类对浮游动物的摄食压力以及中华哲水蚤（Calanus sinicus）的摄食生态学。春季，浮游动物生物量为2.1 g m–2，GC、LC和SC对生物量的贡献率分别为19, 44 和 26%。高生物量的LC和SC功能群主要分布于山东半岛南岸的近岸海域，而GC主要分布在远岸站位。夏季，浮游动物的生物量为3.1 g m–2，GC贡献了73%。GC、LC和SC主要分布在黄海的中部海域。秋季，浮游动物生物量为1.8 g m–2，GC、LC和SC的贡献率相似，分别为36, 33和23%，高生物量的GC和LC分布在黄海中部，而SC主要分布在远岸站位。GC和LC是冬季浮游动物生物量（2.9 g m–2）的优势功能群，分别贡献率了57%和27%，高生物量的GC、LC和SC都分布在黄海的中部海域。与GC、LC和SC相比，毛颚类生物量较低，主要分布于黄海的中北部海域。水母类（本文中指小型水母类）和海樽类斑块分布明显，主要分布于黄海沿岸和北部海域。属于不同功能群的约10个种类为浮游动物的优势种，控制着浮游动物群落的动态。春季，黄海可以被分成4个浮游动物生态区，浮游动物生物量的分布中心位于山东半岛南岸近岸海域，与第一个生态区相对应，LC和SC在分布中心起主要的控制作用；夏、秋和冬季，黄海分别被分成3、4和3个生态区，浮游动物生物量的分布中心均位于黄海的中部海域，均与各季节的第一个生态区相对应，GC和LC是分布中心生态区的优势功能群，对分布中心起主要的控制作用。黄海冷水团（YSCBW）在GC、LC和SC的空间分布模式中起着重要的作用。黄海不同季节浮游动物生态区的空间分布模式及生态区中起控制作用的优势功能群类别有着重要的生态学意义。我们将饵料浮游动物功能群细化为0.16–0.25 mm、0.25–0.5 mm、0.5–1 mm、1–2 mm和 >2 mm5个粒径组。应用生物能量学的方法研究了不同粒径浮游动物的生产力。结果表明：浮游动物次级生产力5月份最高，为91.9 mg C m–2 d–1，其次是6月和9月，分别为75.6 mg C m–2 d–1和65.5 mg C m–2 d–1，8月、3月和12月较低，仅为42.3 mg C m–2 d–1、35.9 mg C m–2 d–1和27.9 mg C m–2 d–1。根据这些结果，黄海浮游动物年次级生产力为18.9 g C m–2 year–1。0.16–0.25 mm和 0.25–0.5 mm 两个粒径组对浮游动物次级生产力的贡献率为58–79%，即相对应的SC功能群的周转率（P/B, 0.091–0.193 d–1）要高于GC和LC。黄海毛颚类功能群的优势种类为强壮箭虫（Sagitta crassa）、纳嘎箭虫（S. nagae）、肥胖箭虫（S. enflata）和百陶箭虫（S. bedoti）。我们对这四种箭虫的生产力和对浮游动物生物量和生产力的摄食压力进行了研究。结果表明：黄海毛颚类总的生物量为98–217 mg m–2，总的生产力为1.22–2.36 mg C m–2 d–1。黄海毛颚类的生物量占浮游动物总生物量的6.35–14.47%，而生产力仅占浮游动物总生产力的2.54–6.04%。强壮箭虫和纳嘎箭虫是黄海毛颚类功能群的绝对优势种，控制着黄海毛颚类群落的动态。黄海毛颚类总的摄食率为4.24–8.18 mg C m–2d–1，对浮游动物现存量和生产力总的摄食压力分别为为0.94%和12.56%。黄海冬季，浮游动物的现存量和生产力为0.4 g C m–2和0.026 g C m–2d–1，而毛颚类的摄食压力却达到了全年的最大值，为1.4%和20.94%。因此，毛颚类的摄食可能对冬季浮游动物群落结构造成重要的影响。通过不同体长组箭虫的摄食率可以推断，黄海毛颚类全年主要摄食小型桡足类，对SC功能群的摄食压力最大。但是在夏季黄海冷水团形成的月份，毛颚类对前体长为2 mm的LC功能群中的种类摄食压力也较大，但此时，由于优势种中华哲水蚤进入滞育阶段，因此毛颚类的摄食会对其种群数量造成严重的影响。中华哲水蚤在春、秋季的摄食率分别为2.08–11.46和0.26–3.70 µg C female–1 day–1，与微型浮游生物的现存量呈显著的正相关。春季，在黄海的北部，中华哲水蚤通过摄食微型浮游生物吸收的碳量能够满足其代谢和繁殖需求，而在黄海的南部和秋季黄海冷水团锋区附近，中华哲水蚤必须通过摄食其他类型的食物资源来维持其代谢和生殖需求。较低的摄食率、无产卵以及种群中CV期桡足幼体占优势表明，秋季中华哲水蚤在黄海冷水团区域内处于滞育状态。中华哲水蚤优先摄食微型原生动物，并且春季中华哲水蚤总的生长效率（GGE, 3–39%）与食物中微型原生动物的比例呈显著的正相关，表明微型原生动物具有较高的营养价值。但是，因较低的产卵率（0.16–12.6 eggs female–1 day–1）而导致的中华哲水蚤较低的总生长效率（13.4%），可能就是由于其食物中的必需营养成分含量不足（或缺乏）造成的。本文从生物量的角度，对黄海浮游动物各功能群的时空分布、生态区划分进行了研究报道，对GC、LC和SC功能群的生产力、毛颚类对浮游动物的摄食压力和中华哲水蚤的摄食生态学进行了较为深入的研究，这些结果为黄海食物产出的关键过程的模拟提供了基础资料。今后的研究重点应搞清楚黄海水母类对浮游动物次级生产力的摄食压力和海樽类在食物产出模型中产生的负效应的程度，浮游动物各功能群的组成、季节变化和空间分布模式的长期变化，尤其是在气候变化和人类活动的影响下，将是今后研究的重点。
其他摘要	Zooplankton plays a vital role in the marine ecosystems. The variations of zooplankton species composition, biomass and secondary production will change the structure and function of the ecosystems. How to describe this process and make it easier to be modeled in the Yellow Sea ecosystem is the main purpose of this paper. The biomass and secondary productivity are the basis of the food web in the marine ecosystem. Who are the main contributors in the biomass and secondary productivity of zooplankton? Which species take the roles to affect the structure and function of the ecosystem? It is very hard to describe in the temperate continental shelf area, such as in the Yellow Sea, where the species composition, biomass and secondary production changed seasonally. Therefore, when modeling the key process of ecosystem food production in the Yellow Sea, an approach which is both precise and easy must be applied. After adequately analyzing the structure of zooplankton community and features of physical oceanography, the zooplankton functional groups approach, which is considered to be a good method of linking the structure of food webs and the energy flow through ecosystems, is used in the Yellow Sea ecosystem modeling. According to the size spectrum, feeding habits and trophic functionality, the zooplankton could be classified into 6 functional groups: giant crustacean (GC), large copepods (LC), small copepods (SC), chaetognaths, medusae and salps. The GC, LC and SC groups which are the main food resources of fish are defined based on the size spectrum. Medusae and chaetognaths are two gelatinous carnivorous groups, which compete with fish for food. The salps group, acting as passive filter-feeders, competes with other species feeding on phytoplankton, but their energy could not be efficiently transferred to higher trophic levels. From the viewpoint of biomass, the seasonal variations and geographical distributions of each zooplankton functional group, the ecoregions related to zooplankton functional groups, the secondary production of zooplankton, the impact of chaetognaths group feeding on zooplankton and trophic ecology of Calanus sinicus were studied in this paper. The mean zooplankton biomass was 2.1 g dry weight m–2 during spring, to which the GC, LC and SC contributed 19, 44 and 26%, respectively. High biomasses of the LC and SC were distributed at the coastal waters, while the GC was mainly located at offshore stations. In summer, the mean biomass was 3.1 g dry weight m–2 which was mostly contributed by the GC (73%), and high biomasses of the GC, LC and SC were all distributed in the central part of the Yellow Sea. During autumn, the mean biomass was 1.8 g dry weight m–2 which was similarly constituted by the GC, LC and SC (36, 33 and 23%, respectively) and high biomasses of the GC and LC were occurred in the central part of the Yellow Sea, while the SC was mainly located at offshore stations. The GC and LC dominated the zooplankton biomass (2.9 g dry weight m–2) in winter, each contributing 57% and 27% and they as well as the SC were all mainly located in the central part of the Yellow Sea. The chaetognaths group was mainly located in the central and northern part of the Yellow Sea during all seasons, but contributed lower to the biomass compared with other groups. The small medusae and salps groups were distributed unevenly with sporadic dynamics, mainly along the coast line and at the northern part of the Yellow Sea. No more than 10 species belonging to the respective functional group dominated the zooplankton biomass and controlled the dynamics of the zooplankton community. During spring, the Yellow Sea can be divided into 4 zooplankton ecoregions. The high biomass of zooplankton was mainly distributed at the coastal waters near the south shore of Shandong peninsula, which corresponded to the first ecoregion. The LC and SC were the dominated functional groups in the first ecoregion. In summer, autumn and winter, the Yellow Sea can be classified into 3, 4 and 3 zooplankton ecoregions, and the high biomass were all mainly distributed in the central part of the Yellow Sea, which all corresponded to the first ecoregion. The GC and LC were the dominated functional groups in the first ecoregion in these three seasons. The Yellow Sea Cold Bottom Water (YSCBW) plays a vital role in the distribution mode of GC, LC and SC. The geographical distribution mode of each zooplankton ecoregion in different season had important ecological meaning in the Yellow Sea ecosystem. In terms of size spectrum, the main food zooplankton of higher trophic levels can be divided into 5 classes of 0.16–0.25 mm, 0.25–0.5 mm, 0.5–1 mm, 1–2 mm and >2 mm using sieves onboard. The secondary production of each size class was estimated by using physiological method. The results showed that the estimated production rate of zooplankton was enormously high in May 2007 (91.9 mg C m–2 d–1), followed in order by June (75.6 mg C m–2 d–1), September (65.5 mg C m–2 d–1), August (42.3 mg C m–2 d–1), March (35.9 mg C m–2 d–1) and December (27.9 mg C m–2 d–1). On the basis of these rates, the integrated production of zooplankton was 18.9 g C m–2 year–1 in the Yellow Sea. The 0.16–0.25 and 0.25–0.5 mm classes which correspond to the SC group together comprised 58–79% of the production in the study area. The P/B value of 0.16–0.25 and 0.25–0.5 mm (0.091–0.193 d–1) were higher than other size classes. Sagitta crassa, S. nagae, S. enflata and S. bedoti were the dominated species of chaetognaths group. The production of these four species as well as feeding impact of them on zooplankton secondary production was estimated in this paper. The results showed that the biomass and estimated production rate of chaetognaths were in the range of 98–217 mg m–2 and 1.22–2.36 mg C m–2 d–1. The proportion of chaetognath biomass was 6.35–14.47% of the zooplankton biomass, while chaetognath production rate was 2.54–6.04% of the zooplankton production. S. crassa and S. nagae were the absolutely dominated species, controlling the dynamics of chaetognath community. The feeding rate of chaetognath ranged from 4.24–8.18 mg C m–2d–1, and feeding impact on biomass and secondary production of zooplankton were 0.94% and 12.56%. In winter, the biomass and production of zooplankton were only 0.4 g C m–2 and 0.026 g C m–2d–1, while the feeding impact peaked in winter at 1.4% and 20.94%. Therefore, the structure of zooplankton community may be significantly affected by chaetognath in winter. On the basis of feeding rate of different body length groups, we can conclude that chaetognaths mainly feed on the species in SC group throughout the year. And besides small copepods, the species in LC group, such as C. sinicus, was largely feed by chaetognahs. Because C. sinicus was in diapause, so C. sinicus community would be affected significantly by chaetognaths in summer. The ingestion rate of C. sinicus (2.08–11.46 and 0.26–3.70 μgC female–1 d–1 in spring and autumn, respectively) was positively correlated with microplankton carbon concentrations. In the northern part of the Yellow Sea, feeding on microplankton easily covers the respiratory and production requirements, whereas in the southern part in spring and in the front zone in autumn, C. sinicus must ingest alternative food sources. Low ingestion rates, no egg production and the dominance of the fifth copepodite (CV) stage indicated that C. sinicus was in quiescence inside the YSCBW area in autumn. C. sinicus ingested ciliates preferentially over other components of the microplankton. The EPR (0.16–12.6 eggs female–1 d–1 in spring and 11.4 eggs female–1 d–1 at only one station in autumn) increased with ciliate standing stock. Gross growth efficiency (GGE) was 13.4% (3–39%) in spring, which was correlated with the proportion of ciliates in the diet. These results indicate that ciliates have higher nutrient quality than other food items, but the low GGE indicates that the diet of C. sinicus is nutritionally incomplete. The feeding impact of medusae group on zooplankton, the ecological effects of salps group in the ecosystem, long term variations of seasonal and spatial distribution and composition patterns of zooplankton functional groups, especially under the climate changes and human perturbations, should be considered in the future.
页数	131
语种	中文
文献类型	学位论文
条目标识符	http://ir.qdio.ac.cn/handle/337002/1425
专题	海洋环流与波动重点实验室
推荐引用方式 GB/T 7714	霍元子. 黄海浮游动物功能群的研究[D]. 海洋研究所. 中国科学院海洋研究所,2008.

条目包含的文件
文件名称/大小	文献类型	版本类型	开放类型	使用许可
10001_20051800681202（3546KB）			限制开放	--	浏览