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1.
Federica Semprucci Paolo Colantoni Giuseppe Baldelli Marco Rocchi Maria Balsamo 《Marine Ecology》2010,31(4):592-607
The Maldivian archipelago comprises some of the most characteristic and significant world atoll systems, but the meiobenthic assemblages of these islands continue to be largely unknown. To investigate variations in meiofaunal spatial distribution and biodiversity in back‐reef platforms, three transects were studied, two at Felidhoo (the north and east sides) and one at South Malé. The sedimentological features of the samples obtained were also analyzed to further current knowledge on the relationships that exist between sediments and meiofauna. Our results reveal that the meiofaunal assemblage at these locations is well diversified and includes 20 major taxa. Nematodes and copepods are dominant, together forming 68% of the total meiofauna, followed by platyhelminthes, polychaetes and ostracods. The nematode assemblage is very rich and composed of 34 families and 123 genera – 96 of which (78%) set new records for the Maldives. The structures of the meiofaunal and nematode assemblages are relatively similar on the ‘large‐scale’ level (i.e. when the different platforms are compared) and reveal a low β‐diversity. However, significant dissimilarities were detected within each platform, emphasizing that such ‘small‐scale’ differences are the main factors determining the structure of the meiofauna and, in particular, the nematode assemblages. Although significant differences were not detected between the transects, greater levels of dissimilarity were recognized at North Felidhoo. Here, the building of inclined deposit layers plays a significant role in increasing the heterogeneity of the platform habitats and sediments, confirming the great importance of sediment granulometry as an environmental variable. Indeed, a close relationship is observed between meiofauna (especially for the nematodes) and grain size, which appears to control the structure, diversity and trophic composition of the Maldivian meiofauna assemblages, thus highlighting the high biodiversity existing in the medium‐coarse sands. 相似文献
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Sediment samples were collected in the intertidal zone of the Dagu River Estuary, Jiaozhou Bay, China in April,July and October 2010 and February 2011 for examining seasonal dynamics of meiofaunal distribution and their relationship with environmental variables. A total of ten meiofaunal taxa were identified, including free-living marine nematodes, benthic copepods, polychaetes, oligochaetes, bivalves, ostracods, cnidarians, turbellarians,tardigrades and other animals. Free-living marine nematodes were the most dominant group in both abundance and biomass. The abundances of marine nematodes were higher in winter and spring than those in summer and autumn. Most of the meiofauna distributed in the 0–2 cm sediment layer. The abundance of meiofauna in hightidal zone was lower than those in low-tidal and mid-tidal zones. Results of correlation analysis showed that Chlorophyll a was the most important factor to influence the seasonal dynamics of the abundance, biomass of meiofauna and abundances of nematodes and copepods. CLUSTER analysis divided the meiofaunal assemblages into three groups and BIOENV results indicated that salinity, concentration of organic matter, sediment sorting coefficient and sediment median diameter were the main environmental factors influencing the meiofaunal assemblages. 相似文献
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为探究莱州湾和牟平近海小型底栖生物群落组成及影响因子,作者于2016年7月在这两个海域采集了沉积物样品,并结合沉积环境因子进行了小型底栖生物群落组成分析。结果表明,在莱州湾和牟平近海各仅检获了7个小型底栖生物类群,且莱州湾的小型底栖生物平均丰度和生物量均明显低于牟平近岸海域。莱州湾线虫和桡足类平均丰度分别占小型底栖生物的91.9%和6.3%,牟平近海分别占92.1%和4.2%。对两个海域小型底栖生物群落组成与环境因子进行Pearson相关性分析,结果显示:小型底栖生物丰度与底层水溶解氧含量呈显著正相关;表层小型底栖生物丰度比与沉积物中叶绿素a含量、脱镁叶绿素含量、沉积物有机质含量以及水深呈显著正相关,与中值粒径和底层水温度呈显著负相关。本研究显示,基于不同沉积物类型中的参考比值,线虫和桡足类丰度比值(N/C)可用于莱州湾和牟平近海沉积环境有机污染状况的评估。研究还发现,牟平海域的小型底栖生物丰度和生物量呈现由近岸向外海增加的异常趋势,且小型底栖生物的数量和类群多样性较十年前显著降低,显示沉积环境受到了明显干扰。 相似文献
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为研究南黄海小型底栖动物的空间分布格局及其环境影响因素,于2020年8月（夏季）和11月（秋季）对南黄海进行了两个航次的野外观测和采样,对小型底栖动物的类群组成、丰度、生物量、垂直分布、群落结构及其与环境因子的关系进行了研究。结果显示,共鉴定出小型底栖动物类群15个,其中自由生活海洋线虫为最优势类群,在两个航次中分别占小型底栖动物总丰度的75.6%和84.6%。其他较重要的类群还包括底栖桡足类、轮虫类和枝角类等。夏季和秋季小型底栖动物的平均丰度分别为（514.9±32.1）ind./(10 cm2) 和（350.8±30.7）ind./(10 cm2),平均生物量（干质量）分别为（651.7±98.0）μg/(10 cm2)和（589.2±37.1）μg/(10 cm2)。小型底栖动物在时空分布上存在差异。在季节分布上,小型底栖动物丰度和类群组成存在极显著差异。结合环境因子分析结果可知,沉积物中值粒径是引起差异的主要环境因子。在空间分布上,夏季小型底栖动物丰度和类群组成在不同水深间存在极显著差异,秋季小型底栖动物丰度和类群组成在不同水深间差异不显著。推测黄海冷水团是影响夏季小型底栖动物空间分布差异的主要因素。本研究中小型底栖动物的数量和类群多样性相较于国内其他对南黄海小型底栖动物的研究较低,其中沉积物叶绿素a含量及有机质含量是引起南黄海小型底栖动物丰度变化的重要因素。海洋线虫与桡足类的丰度比值（N/C比值）评估显示秋季该区域存在有机污染,这一结果与应用大型底栖动物对同一区域进行环境评价的结果不一致,对于应用N/C比值评价环境质量还需要进一步的研究。 相似文献
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我国的海洋生物多样性及其保护 总被引：20，自引：0，他引：20
本文综述了我国海洋生态系统多样性、海洋物种多样性及其利用以及海洋生物遗传多样性的现状，指出过度捕捞、生境丧失、环境污染、生态入侵是威胁我国海洋生物多样性的主要原因。文本还阐述了我国在海洋生物多样性保护、海洋生态环境监测、海洋自然保护区建设及管理上所取得的成就，以及在海洋生物多样性可持续利用方面所取得的进展。 相似文献
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海洋生物多样性是海洋生态系统的重要组成部分,了解海洋生物多样性的形成演化过程不仅是生命科学的本质问题,而且对海洋生物资源的保护和开发利用具有重要的指导意义。目前海洋生物多样性的形成演化机制尚不明确,而性状多样性的起源和适应性演化为回答海洋生物多样性的内源性机制提供了重要突破口。本文从演化发育生物学的角度综述了海洋动物适应性性状、其研究方法和新兴模式生物的研究进展,重点阐述了印太交汇区的海洋动物适应性演化研究进展,探讨了该区域生物多样中心形成的驱动力,并就未来海洋生物多样性与适应性演化研究提出了建议。 相似文献
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《Marine Policy》2013
This paper explores the utility of qualitative scenario approaches to examine the potential impacts of climate change on marine biodiversity conservation on the east coast of Australia. This region is large and diverse, with considerable variation in marine biodiversity and, concomitantly, considerable diversity in the likely impacts from climate change. The results reinforce a number of key points. Engaging with stakeholders in scenario planning provides not only a focus to discuss the future in a disciplined way, but also provides ongoing reference points for contemporary decision making and planning. The paper illustrates how qualitative scenario planning provides opportunities to address the challenges of marine biodiversity conservation in a changing environment. 相似文献
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根据2006年7月13日至8月30日在长江口及邻近陆架海区采集的小型底栖动物样品,对小型底栖动物类群组成,丰度、生物量的水平分布和垂直分布以及调查海区的环境因子进行了研究。结果表明：研究海域小型底栖动物有线虫、桡足类、多毛类、寡毛类、介形类、螨类、双壳类、腹毛类、动吻类、端足类和等足类等11个类群及无节幼体等。平均丰度为453.22±355.34 ind/10 cm2,最优势类群为线虫,占小型底栖动物总丰度的81.37%,次优势类群分别为底栖桡足类和多毛类,分别占小型底栖动物总丰度的10.13%和2.96%。平均生物量为622.65±505.07 μg/10 cm2,生物量占比最高的类群为多毛类,占总生物量的30.21%,其次分别为线虫和寡毛类,分别占小型底栖动物总生物量的23.69%和19.44%。水平分布上,从河口冲淡水区到东海陆架深水区,小型底栖生物丰度呈现由低到高的变化趋势,杭州湾小型底栖动物丰度为240.96±223.47 ind/10 cm2,长江口近岸区为442.91±304.16 ind/10 cm2,东海陆架深水区为865.42±553.88 ind/10 cm2。垂直分布上,小型底栖动物主要分布在0~2 cm层,丰度为290.28±250.03 ind/10 cm2;其次是2~5 cm层,丰度为132.81±128.74 ind/10 cm2;5~10 cm层分布最少,丰度为30.14±31.91 ind/10 cm2。其中线虫、多毛类、寡毛类与桡足类等主要类群的垂直分布与总分布趋势相同。与环境因子进行相关分析表明,调查海区小型底栖动物的丰度主要与水深、盐度和溶解氧显著相关,对小型底栖动物分布影响最大的环境因子组合为溶解氧和盐度。 相似文献
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Meiobenthos at the mouth of the Grevelingen and Oosterschelde Estuaries in the Southern Bight of the North Sea was monitored using meiobenthic abundance and nematode community structure. Hierarchical sampling included 54 subsamples nested within 18 cores within six stations within two transects. The spatial patterns of the meiofaunal populations and communities are presented in cm-scale (among subsamples), m-scale (among cores), km-scale (among stations) and 10 km-scale (between transects). The variance components analysis of meiofaunal abundances showed that km-scale and 10 km-scale represented 63–90% of total variance while m-scale and cm-scale provided only 10–37%. Different communities were found among stations rather than among cores or subsamples by detrended correspondence analysis ordination and clustering analysis. The main assemblage of meiofauna occurred at the km-scale. Nematode diversity was more powerful than meiofaunal abundance in detecting spatial variation at all scales. However, at least two replicates are required for monitoring when sampling using a 10 cm2 subsampling core. 相似文献
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Bathymetric patterns of meiofaunal abundance and biomass associated with the Kuril and Ryukyu trenches, western North Pacific Ocean 总被引：2，自引：0，他引：2
Makoto Itoh Kiichiro KawamuraTomo Kitahashi Shigeaki KojimaHideki Katagiri Motohiro Shimanaga 《Deep Sea Research Part I: Oceanographic Research Papers》2011,58(1):86-97
The abundance and biomass of metazoan meiofauna and their relationships with environmental factors [chloroplastic pigment equivalents (CPE) and sediment characteristics] were studied quantitatively around and within the Kuril Trench (560-7090 m) and the Ryukyu Trench (1290-7150 m), which are located in eutrophic and oligotrophic regions, respectively, of the western North Pacific. Faunal abundance and biomass, as well as the CPE content of sediments, were considerably higher in the Kuril region than in the Ryukyu region. In both cases, CPE tended to decrease with water depth, but relatively high values were found in the deepest areas, suggesting that organic matter has accumulated in both trenches. Meiofaunal abundance and biomass were lower than expected from sediment CPE values at hadal stations below 6000 m. Differences in the density and biomass of meiofauna between these two trenches appeared to reflect differences in overall ocean productivity above them. When the analysis was restricted to each region, however, no association was found between the abundance and biomass of meiofauna and food availability. Furthermore, the factors regulating the bathymetric patterns in these meiofaunal parameters appeared to differ between the two trenches. 相似文献
12.
Daniela Zeppilli Marianna Mea Cinzia Corinaldesi Roberto Danovaro 《Progress in Oceanography》2011,91(3):260-272
Mud volcanoes are cold seeps, in which the escape of gas and fluids associated with mud creates 3-D bottom structures that enhance the spatial heterogeneity and potentially alter the functioning of the benthic ecosystems. We investigated a complex system of mud volcanoes of the Mediterranean Sea characterised by the presence of different structures (i.e., isolated domes, domes surrounded by moats, clustered domes, and ridges) displaying different levels of seepage. We hypothesize that the combined effects of seafloor heterogeneity (i.e., different 3-D structures as revealed by detailed topographic analysis), fluid emissions and trophic characteristics of these systems can influence the structural and functional biodiversity of meiofauna (with special focus on the nematodes). We found that sediments affected by intensive seepage displayed the lowest faunal abundances and number of higher taxa. However, mud volcanoes without emissions, but characterized by a high structural complexity (such as the ridges), were associated with the highest meiofaunal abundances and number of higher taxa. Mud volcanoes hosted also a remarkable abundance of rare taxa specifically associated with these structures (e.g., acarians, cumaceans, tanaids, cladocerans and hydroids) and absent in slope sediments (used as a control). Each mud-volcano area displayed a different nematode species composition. Overall 76 nematode species (from a total of 235) were exclusively associated with mud-volcano structures, whilst 29 were exclusively encountered in slope sediments. We conclude that the presence of mud volcanoes, for their contribution to increase spatial heterogeneity and for the extreme conditions associated with gas emissions, promotes higher levels of beta diversity, thus enhancing the regional (gamma) benthic diversity. These findings provide new insights on the factors controlling meiobenthic biodiversity in mud volcanoes and clues for future action of conservation of the biodiversity specifically associated with these habitats. 相似文献
13.
东海北部小型底栖动物群落对径流及黑潮暖流入侵的响应 总被引：1，自引：1，他引：0
为探究小型底栖动物群落在东海北部及其临近海域的分布规律，及其对环境因子的响应，于2016年9月和12月，对研究海域共计20个站位的小型底栖动物和环境因子进行了取样调查。调查结果显示，研究海域内共鉴定出小型底栖动物类群16个，其中海洋线虫为绝对优势类群，其他优势类群主要包括桡足类、动吻类和多毛类。9月航次小型底栖动物平均丰度为(1 758±759)个/（10 cm2），线虫占95.6%；平均生物量为(1 216.4±464.7) μg/(10 cm2)(干重)，线虫占55.26%。12月航次平均丰度为(2 011±1 471)个/(10 cm2)，线虫占95.6%；平均生物量为(1 143.0±755.0)μg/(10 cm2)(干重)，线虫占67.28%。聚类分析结果显示，小型底栖动物群落主要可以划分为近岸和外海两个组，其中近岸组小型底栖动物丰度显著高于外海站位。但在各断面分布上，绝大多数站位小型底栖动物丰度最高值均出现在60 m等深线附近，并且该水深处站位的温度和盐度数值均表现出黑潮水的特征。黑潮近岸分支对东海陆架入侵是导致小型底栖动物分布差异的重要原因，小型底栖动物在60 m等深线附近具有的高丰度值可作为其对黑潮入侵的响应。推测，黑潮入侵所导致的水体初级生产力增加以及黑潮水所携带的溶氧可能是导致该深度处小型底栖动物丰度增加的主要原因。 相似文献
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基于海岸带综合管理的理念,通过海域生态环境敏感性评价与海域生物多样性保护重要性评价,综合利用地理相关分析法、空间叠置法等定性和定量分区相结合的方法进行海洋生物多样性保护空间规划分区划界,提出了海洋生物多样性保护空间规划分区体系,将规划区域划分为生物多样性重点保护区、生物多样性养护区和生物多样性保护重点监督区.以福建泉州湾为案例,应用海洋生物多样性保护空间规划分区体系,得出泉州湾生物多样性保护极重要地区是泉州湾河口湿地省级自然保护区,泉州湾生物多样性保护比较重要地区是晋江河口、洛阳江河口、晋江南岸地区及清源山.泉州湾海洋生物多样性保护空间规划分区方案共划定26个分区,包括生物多样性重点保护区3个,生物多样性养护区14个,生物多样性保护重点监督区9个.泉州湾的应用结果表明,本研究提出的海洋生物多样性保护空间规划分区体系具有一定的可行性和可操作性,可为泉州湾生物多样性保护管理提供重要科学依据. 相似文献
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Taciana K. Pinto Melanie C. V. Austen Richard M. Warwick Paul J. Somerfield André M. Esteves Francisco J. V. Castro Verônica G. Fonseca‐Genevois Paulo J. P. Santos 《Marine Ecology》2013,34(3):257-268
Mangroves are highly productive environments that play important ecological and socioeconomic roles; however, they have been impacted to different degrees in most countries worldwide. The knowledge of which organisms inhabit this environment and their ecological interactions is the first step towards its conservation. The natural variability of environmental factors in mangroves provides numerous niches available to different species. Meiofauna have patchy patterns of distribution that are related to the availability of resources. Hence, meiofauna are expected to present a high diversity of different taxa occupying the different microhabitats offered by mangroves. This work aims to test the hypothesis that the assemblage structure of Nematoda varies significantly among mangrove microhabitats and to contribute knowledge on the meiofauna diversity in mangrove environments. This work was carried out in a mangrove region at Pernambuco state, Northeastern Brazil. Qualitative samples were collected in nine microhabitats which show different characteristics mainly in terms of presence of vegetation or another organism and sediment grain size. Univariate and multivariate analysis were applied to Nematoda genera abundance data. Our results demonstrate the existence of significant differences among microhabitats regarding nematode assemblage structure corroborating the hypothesis. Different Nematoda assemblages are present in at least seven microhabitats. These assemblages are composed of nematode genera with different trophic and morphological features, demonstrating a strong relationship between morphological diversity and ecological plasticity. Furthermore, this study also demonstrates the importance of the conservation of this ecosystem and its attributes. 相似文献
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Characterisation of productivity-diversity relationships forms an essential step towards a better understanding of biodiversity. In terrestrial systems this is a topical subject and most studies reported a hump-shaped relationship. For marine systems, however, the number of studies dedicated to this is low despite the high interest in this productivity-diversity relationship. The present study reports on meiofauna density/diversity patterns in relation to resource availability as an indicator for the productivity of the ecosystem. Standardised meiofauna samples were collected in tropical seagrass beds from three localities (Kenya, Mexico, the Philippines) in order to contrast local patterns with a more global scale. Although these sites were physically comparable, a range of resource availabilities was found. These differences between localities were mainly due to different tidal regimes and related input of organic matter. At all sites a significant positive effect of resource increase on meiofauna densities was found. This positive effect was less clear for meiofauna diversity. Highest density and diversity levels were reported for the Kenyan site and this is probably linked to a high tidal range. Pooling all localities together resulted in a significant positive linear relationship between resource availability and meiofauna density/diversity. Caution should be taken when choosing resource indicators. Chlorophyll a concentrations, for example, resulted in a positive density-productivity relationship while organic carbon content, an indicator for more refractory material, showed a negative relationship. In all cases, no hump-shaped relationship could be found suggesting that each ecosystem and each group of organisms may show a particular productivity-diversity/density relationship. 相似文献
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Previous studies at the Isla Vista oil seep have suggested that meiofauna, particularly nematodes, might be an important factor in explaining macrofaunal enrichment by making bacterial biomass available to the benthic food web. To explore this possibility, we analyzed meiofaunal abundance and microalgal pigments inside and just outside of bacterial mats at this natural oil seep.The bacterial mats occur where crude oil and natural gas are actively seeping out of the sediment; cores from within the mats contained a great deal of crude oil (up to 50 %). Meiofaunal abundances were the same in and out of the bacterial mats (averaging 1·-9 × 106 individuals m-2). However, dramatic changes in community structure were noticed. Harpacticoids made up 19 % of the fauna outside the mats but only 1 % inside. Pigment concentrations were also the same in both sites with phaeophytin dominating chlorophyll (120 compared to 29.8 mg m-2). The variance of both microalgal pigments and meiofauna was much greater inside than outside, suggesting that the bacterial mats are a more heterogeneous environment.Although the effect of crude oil toxicity is not clear, the high abundances of microbial and meiofaunal biomass support the hypothesis of benthic enrichment via microbes and meiofauna. 相似文献
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Biological diversity, or biodiversity, is high on the international agenda for nature conservation. Marine and coastal ecosystems account for an important share of the biological diversity on Earth. As a consequence many international conventions, European legislation and national laws refer to marine biodiversity. The protection of marine biodiversity is a complex legal issue as it requires consideration of geographic (between land and sea), political (between conservation and exploitation), and economic (between fisheries, tourism, intellectual property and many other sectors) factors. Like Matryoshka dolls, marine biodiversity is a heterogeneous notion difficult to address as one discrete area in the development of policy agendas or juridical frameworks. In the past decade, the EU has been very active in Promoting Integrated Coastal Zone Management and in developing a framework for an Integrated Maritime Policy. This article reviews the status of marine biodiversity in the policy and legal initiatives of the European Union, a challenging issue to both the objectives of conservation and to the concept of integration. 相似文献
20.
中国多金属结核开辟区东、西两小区小型底栖动物的空间分布 总被引：1，自引：1，他引：1
利用 1 998年“大洋一号”调查船 DY95 - 8航次在中国多金属结核开辟区东、西两小区用多管取样器采集的沉积物样品 ,对小型底栖动物的组成、分布及其与环境因子的关系进行了研究。结果表明 :(1 )东、西两小区共有 1 6个类群的小型底栖动物 ,其中线虫类占居显著优势 ,在东、西两小区各占总栖息密度的 71 %和 6 4 %,其次为猛水蚤类和蜱螨类。 (2 )东、西两小区小型底栖动物类群平均栖息密度分别为 3 2 .47ind/1 0 cm2 和 1 8.0 5 ind/1 0 cm2 ,东小区高于西小区。小区各站位间的栖息密度平面分布差异显著。 (3 )东、西两小区小型底栖动物类群栖息密度的垂直分布趋势明显 ,由表层向底层 ,栖息密度逐渐降低。 (4)东、西两小区小型底栖动物空间分布与底质沉积物、结核覆盖率和底层流等环境因子密切相关 ,底质较硬、结核覆盖率较高以及底层流较强都不利于小型底栖动物的栖息。 相似文献