海南岛周边海域造礁石珊瑚的群落结构及其分布

基于形态学分类鉴定,并辅以分子标记,我们于2014–2015年调查分析了海南岛文昌云龙湾、万宁大洲岛、儋州磷枪石岛、昌江沙鱼塘村、三亚鹿回头海域造礁石珊瑚的种类组成和分布。结果表明,海南造礁石珊瑚的分布较为广泛,共鉴定出10科17属55种,其中鹿角珊瑚科、滨珊瑚科和蜂巢珊瑚科为优势科。各海域造礁石珊瑚的群落结构不同:南部三亚鹿回头海域以分枝状鹿角珊瑚为主,东部文昌云龙湾和万宁大洲岛海域分别以叶片状和分枝状蔷薇珊瑚为主,而西部儋州磷枪石岛和昌江沙鱼塘村则分别以团块状滨珊瑚和蜂巢珊瑚为主。不同的地理环境使海南岛周边海域珊瑚礁群落呈现出不同的演替型,具有明显的地域性分布特点。5个不同海域造礁石珊瑚的覆盖率和多样性指数依次为:三亚鹿回头文昌云龙湾昌江沙鱼塘村万宁大洲岛儋州磷枪石岛,覆盖率和多样性指数具有明显的正相关性。与2005–2010年的调查结果相比,文昌云龙湾和万宁大洲岛保护区造礁石珊瑚的覆盖率和多样性指数有所上升,昌江沙鱼塘村和三亚鹿回头相对稳定,儋州磷枪石岛则下降比较明显。死亡率较高的是昌江沙鱼塘村邻近海域,且多为最近半年内死亡。人类活动(保护性或破坏性)极大地影响着造礁石珊瑚的多样性、覆盖率和死亡率。     

鹿回头库礁造礁石珊瑚物种多样性的研究

定量分析鹿回头岸礁造礁石珊瑚群落的种类组成,选择α－多样性和β－多样性的度量方法,分析了该群落造礁石珊瑚种、属和科的多样性及其与所处生境的关系。结果表明：鹿回头岸礁造礁石珊瑚群落的物种比较丰富,多样性和均匀度指数都较高,但在不同地段之间存在着明显的差异。水深中等的地段（２．４～５．０ｍ）的多样性指数高于较浅（１．５～２．０ｍ）和较深（５．５～６．５ｍ）地段;期间带与潮下带之间和礁平台与向海斜坡之间的两个过渡地带的生境条件复杂,物种多样性和种类分布的混杂程度都高于其他地段。     

鹿回头岸礁造礁石珊瑚物种多样性的研究

定量分析鹿回头岸礁造礁石珊瑚群落的种类组成,选择α－多样性和β－多样性的度量方法,分析了该群落造礁石珊瑚种、属和科的多样性及其与所处生境的关系。结果表明：鹿回头岸礁造礁石珊瑚群落的物种比较丰富,多样性和均匀度指数都较高,但在不同地段之间存在着明显的差异。水深中等的地段（２．４￣５．０ｍ）的多样性指数高于较浅（１．５￣２．０ｍ）和较深（５．５￣６．５ｍ）地段;潮间带与潮下带之间和礁平台与向海斜坡之间     

广西涠洲岛造礁珊瑚种群结构的空间分布

对2007年和2008年调查的涠洲岛沿岸海域垂直海岸方向的6条主剖面上20条分断面的影像资料、样品鉴定等资料的分析,涠洲岛石珊瑚共出现10科22属46种,9个未定种;角蜂巢珊瑚属(Favites)、滨珊瑚属(Porites)、蔷薇珊瑚属(Montipora)为优势类群,其属级重要值百分比分别为25.78%、17.47%、15.11%;各主剖面珊瑚种群优势类群分布各有差异,以西南部的W2、东北部的W5的珊瑚属种为较多,均为8科13属,其石珊瑚属种分布均匀度略高;涠洲岛珊瑚分布自岸向海分为砂砾及珊瑚断枝带、石珊瑚稀疏带、石珊瑚繁盛带、柳珊瑚繁盛带4 个生物地貌带,石珊瑚分布较多的石珊瑚繁盛带主要分布于-1.39--5 m的水深范围内。石珊瑚形态组合以块状/亚块状与板块状为主要类型,覆盖程度以块状/亚块状占优。调查区受1998年的"厄尔尼诺现象"引起的全球性极高温事件和2008年1-2月的极低温气候事件及地域性不合理人类活动胁迫影响较大,枝状形态石珊瑚覆盖度、优势程度下降,已退出属种优势组合。     

造礁石珊瑚记录现代海洋生态环境信息研究进展

造礁石珊瑚因其独特的生物学和生态学特性,已被广泛用作环境因子的代用指标.过去国内外的研究主要侧重于地质年代环境信息的记录,随着样品分析测试精度的提高,用造礁石珊瑚骨骼研究现代热带的生态环境也逐渐增多,尤其对于影响海洋生态环境的事件信息的记录.许多研究都证明了造礁石珊瑚骨骼中各种示踪剂在监测过去环境变化方面的有效性,对目前和将来的生态监控以及环境研究都具有广阔的前景.目前,珊瑚基础生理学的机制尚未完全探明,进一步了解珊瑚微观结构层次的生理机制是该领域研究的关键所在.我国学者已开展了南海西沙、南沙、台湾岛、海南岛、徐闻和涠洲岛等地区的造礁石珊瑚骨骼多种指标的研究.     

悬浮物对造礁石珊瑚营养方式的影响及其适应性研究进展

营养方式是造礁石珊瑚获取能量与营养物质的基础,影响其生长与分布。近年来珊瑚礁区悬浮物含量与组分结构发生显著变化,其对造礁石珊瑚营养方式的诸多影响正成为当前研究热点。研究系统综述了珊瑚礁区悬浮物变化特征、悬浮物对造礁石珊瑚营养方式的影响及其适应性研究现状。发现近年来人类活动加剧与强降雨事件频发是驱动珊瑚礁,尤其是近岸珊瑚礁区悬浮物含量递增、组分改变与变频加剧的主因;悬浮物变化对造礁石珊瑚光合自养与异养营养的影响存在显著的种间差异,这主要与悬浮物消光效应、生物可利用性及造礁石珊瑚种类密切相关。虽然少数种类造礁石珊瑚具光合可塑性或异养可塑性,能在高含量悬浮物存在的弱光环境中较好生长。然而对绝大多数造礁石珊瑚而言,其营养方式适应性较差,无法在悬浮物影响下较好地获取生命活动所需的能量与营养物质,进而难以生存。总体来说,悬浮物被认为是近年来影响造礁石珊瑚生长与分布的重要环境因子之一,而关于造礁石珊瑚营养方式对悬浮物变化的响应及其适应机制,当前研究仍较薄弱,需要进一步加强相关研究。     

海南鹿回头岸礁造礁石珊瑚群落结构动态Ⅱ.物种多样性

根据石珊瑚物种的总数、石珊瑚覆盖的百分率、物种多样性和均匀度,对鹿回头岸礁造礁石珊瑚群落结构类型所处在演替阶段的时间状态和生境的空间状态进行分析。在中等和深水区物种多样性的时间变异,随演替的发展而有所下降;浅水区不随演替而变化。在不同生境区珊瑚生长的聚群上,与时间的发展无关;每个演替时期,物种多样性的类型与生境的变化有关。     

鹿回头造礁石珊瑚群落多样性的现状及动态

通过对鹿回头岸礁（１０９°２８＇Ｅ,１８°１３＇Ｎ）造礁石珊瑚群落进行系统取样调查,分析了现有群落整体的成分组成,α－多样性和β－多样性及其在环境梯度上的变化;根据现有群落实际是处于不同演替时期地段的复合体的特点,把处于相同演替时期地段的综合特征作为分析群落整体在相应时期多样性特征的依据,探讨了群落演替过程中的多样性动态。研究发现：①中等水深（２．５￣５．０ｍ）地段的物种多样性平均值高于其他地段,     

涠洲岛42年来海面温度变化及其对珊瑚礁的影响

涠洲岛位于南海珊瑚礁分布的北缘温度是影响其珊瑚礁生态系统发育的重要因素,对器测温度分析发现,近42年来涠洲岛海面温度(SST)与全球气候变暖呈准同步变化趋势,存在3～4年与7～8年的变化周期,20世纪80年代后期以来,涠洲岛SST上升比较明显。其月平均最高SST的持续上升将使本区珊瑚生长处于一种非常敏感的边缘,加上人类活动(建筑取材、炼油、旅游、捕鱼、养殖等)对涠洲岛珊瑚礁的潜在不利影响,则可能导致珊瑚礁的退化。此外,在系统的野外调查基础上,描述了涠洲岛现代珊瑚礁的分布范围。     

西沙群岛海域造礁石珊瑚物种多样性与分布特点

2006年3-5月,采用国际通用的截线样带法对海南省西沙群岛主要珊瑚礁海域的18个岛礁造礁石珊瑚进行了实地调查,共记录13科45属188种,其中62个新记录种.整合文献资料,该海域共记录造礁石珊瑚13科50属204种,基本包括分布在我国(不含台湾省)的所有造礁石珊瑚科属和绝大多数种类.造礁石珊瑚以生长速度快的分枝状珊瑚为主.物种多样性最高的是华光礁海域、金银岛海域和永兴岛海域.聚类分析可以把18个调查岛礁分成3个类群:有人类居住的大型环礁群、独立岛礁群和无人居住的大型环礁群(华光礁).为了有效保护珍稀的造礁石珊瑚资源,按照其种类多样性和分布特点重点保护关键海域是十分必要的.     

Coral Reefs at the Northernmost Tip of Borneo: An Assessment of Scleractinian Species Richness Patterns and Benthic Reef Assemblages

The coral reefs at the northernmost tip of Sabah, Borneo will be established under a marine protected area: the Tun Mustapha Park (TMP) by the end of 2015. This area is a passage where the Sulu Sea meets the South China Sea and it is situated at the border of the area of maximum marine biodiversity, the Coral Triangle. The TMP includes fringing and patch reefs established on a relatively shallow sea floor. Surveys were carried out to examine features of the coral reefs in terms of scleractinian species richness, and benthic reef assemblages following the Reef Check substrate categories, with emphasis on hard coral cover. Variation in scleractinian diversity was based on the species composition of coral families Fungiidae (n = 39), Agariciidae (n = 30) and Euphylliidae (n = 15). The number of coral species was highest at reefs with a larger depth gradient i.e. at the periphery of the study area and in the deep South Banggi Channel. Average live hard coral cover across the sites was 49%. Only 7% of the examined reefs had > 75% hard coral cover, while the majority of the reef sites were rated fair (51%) and good (38%). Sites with low coral cover and high rubble fragments are evidence of blast fishing, although the observed damage appeared old. Depth was a dominant factor in influencing the coral species composition and benthic reef communities in the TMP. Besides filling in the information gaps regarding species richness and benthic cover for reef areas that were previously without any data, the results of this study together with information that is already available on the coral reefs of TMP will be used to make informed decisions on zoning plans for conservation priorities in the proposed park.     

The composition and structure of a protected coral reef in Cam Ranh Bay in the South China Sea

A nonstructural reef at Hon Nai Island in Cam Ranh Bay (southern Vietnam) was investigated. In comparison with most of the coastal continental and island coral reefs of this region, it is characterized by high species richness of reef-building corals, among them scleractinians. A total of 34 species of Acropora were found, which represent 80% of the total species composition of this scleractinian genus on the reefs of Vietnam and 25% on the reefs of the Indo-Pacific. Among 169 species of scleractinians found on the reef of Hon Nai, Favia sp. nov. was previously unknown to science. The vertical bionomic zonality of the reef corresponds to a zonal distribution of environmental factors and is similar to that on reefs of the Gulf of Siam and various areas of the Pacific and the Caribbean Basin. The thriving of the Hon Nai island reef may be connected with protective measures undertaken by the Government of Vietnam and the minimization of anthropogenic impacts due to the activities of the Sanest Co.     

Abrolhos bank reef health evaluated by means of water quality, microbial diversity, benthic cover, and fish biomass data

The health of the coral reefs of the Abrolhos Bank (Southwestern Atlantic) was characterized with a holistic approach using measurements of four ecosystem components: (i) inorganic and organic nutrient concentrations, [1] fish biomass, [1] macroalgal and coral cover and (iv) microbial community composition and abundance. The possible benefits of protection from fishing were particularly evaluated by comparing sites with varying levels of protection. Two reefs within the well-enforced no-take area of the National Marine Park of Abrolhos (Parcel dos Abrolhos and California) were compared with two unprotected coastal reefs (Sebasti?o Gomes and Pedra de Leste) and one legally protected but poorly enforced coastal reef (the "paper park" of Timbebas Reef). The fish biomass was lower and the fleshy macroalgal cover was higher in the unprotected reefs compared with the protected areas. The unprotected and protected reefs had similar seawater chemistry. Lower vibrio CFU counts were observed in the fully protected area of California Reef. Metagenome analysis showed that the unprotected reefs had a higher abundance of archaeal and viral sequences and more bacterial pathogens, while the protected reefs had a higher abundance of genes related to photosynthesis. Similar to other reef systems in the world, there was evidence that reductions in the biomass of herbivorous fishes and the consequent increase in macroalgal cover in the Abrolhos Bank may be affecting microbial diversity and abundance. Through the integration of different types of ecological data, the present study showed that protection from fishing may lead to greater reef health. The data presented herein suggest that protected coral reefs have higher microbial diversity, with the most degraded reef (Sebasti?o Gomes) showing a marked reduction in microbial species richness. It is concluded that ecological conditions in unprotected reefs may promote the growth and rapid evolution of opportunistic microbial pathogens.     

西沙群岛礁栖鱼类物种多样性及其食性特征

通过新的方法(即潜水调查法)调查了西沙群岛浅水区的礁栖鱼类, 并从食性角度分析鱼类群落特征及其对水质环境变化的响应。2006年5-6月, 对西沙群岛6个岛礁(东岛、永兴岛、羚羊礁、金银岛、华光礁和中建岛)共10个站位的礁栖鱼类种类、数量和长度进行了调查, 结合公开资料(FishBase等)确定鱼类食性。共记录到29科71属119种鱼, 其中50种是新记录。至此, 西沙群岛的鱼类总记录已达到717种。从不同站位来看, 永兴岛西的种类数量和Shannon-Wiener多样性指数均最高。多数鱼种分布范围狭小。摄食浮游动物和底栖无脊椎动物的鱼类是优势类群, 而草食性、杂食性和食物链顶端食性的鱼类数量和生物量较低, 反映出西沙群岛珊瑚礁生态系统整体上健康稳定。永兴岛的杂食性鱼类的数量比例和生物量比例均高于其他岛礁, 反映出鱼类群落已对水体富营养化产生响应。     

Newly dominant benthic invertebrates reshape competitive networks on contemporary Caribbean reefs

Competition is a fundamental process structuring ecological communities. On coral reefs, space is a highly contested resource and the outcomes of spatial competition can dictate community composition. In the Caribbean, reefs are increasingly dominated by non-scleractinian species like sponges, gorgonians, and zoanthids, yet there is a paucity of data on interactions between these increasingly common organisms and historically dominant corals. Here, we investigated interactions among these groups of sessile benthic invertebrates to better understand the role of spatial competition in shaping benthic communities on Caribbean reefs. We coupled surveys of competitive interactions on the reef with a common garden competition experiment to determine the frequency and outcome of interference competition among eight focal species. We found that competitive interactions were pervasive on Florida reefs, with 60% of sessile benthic invertebrates interacting with at least one other invertebrate. Increasingly common non-scleractinian species were some of the most abundant taxa and consistently outcompeted the contemporarily common scleractinian species Porites porites and Siderastrea siderea. The encrusting gorgonian, Erythropodium caribaeorum, was the most aggressive species, reducing the live area of its competitors on average 42% ± 7.04 (SE) over the course of 5 months. Surprisingly, the most aggressive species declined in size when competing, while some less aggressive species were able to increase or maintain area, suggesting a trade-off between aggressiveness and growth. Our findings suggest that competition among sessile invertebrates is likely to remain an important process in structuring coral reefs, but that the optimal strategies for maintaining space on the benthos may change. Importantly, many non-scleractinian species that now dominate reefs appear to be superior competitors, potentially increasing the stress on corals on contemporary reefs.

     

Simulations of Long-Term Community Dynamics in Coral Reefs - How Perturbations Shape Trajectories

Tropical coral reefs feature extraordinary biodiversity and high productivity rates in oligotrophic waters. Due to increasing frequencies of perturbations – anthropogenic and natural – many reefs are under threat. Such perturbations often have devastating effects on these unique ecosystems and especially if they occur simultaneously and amplify each other''s impact, they might trigger a phase shift and create irreversible conditions.We developed a generic, spatially explicit, individual-based model in which competition drives the dynamics of a virtual benthic reef community – comprised of scleractinian corals and algae – under different environmental settings. Higher system properties, like population dynamics or community composition arise through self-organization as emergent properties. The model was parameterized for a typical coral reef site at Zanzibar, Tanzania and features coral bleaching and physical disturbance regimes as major sources of perturbations. Our results show that various types and modes (intensities and frequencies) of perturbations create diverse outcomes and that the switch from high diversity to single species dominance can be evoked by small changes in a key parameter.Here we extend the understanding of coral reef resilience and the identification of key processes, drivers and respective thresholds, responsible for changes in local situations. One future goal is to provide a tool which may aid decision making processes in management of coral reefs.     

Patterns of scleractinian coral recruitment at Lord Howe Island,an isolated subtropical reef off eastern Australia

Changing oceanic conditions, particularly ocean warming and altered currents, can affect the reproductive success of corals. Improving the knowledge of coral reproductive processes at the marginal range limits of coral reefs is important for understanding the ecology of subtropical coral communities and the potential for coral species to expand their ranges in higher latitudes in the future. The extent of live coral cover around subtropical Lord Howe Island (LHI; 31°33′S, 159°05′E) approximately 600 km off the east coast of Australia, has been relatively stable over the last several decades; however, shifts in dominant species in the adult coral community have been reported. To examine the potential influences of recent altered currents and shifts in dominant scleractinian taxa within this community, this study examined spatial and seasonal variation of coral larval settlement at different habitats within the LHI reef lagoon. The study also assessed whether the assemblage of scleractinian corals settling at LHI has changed between 1990–1991 and 2011–2012. Mean densities of coral settlement in 2011–2012 (230 spat m^?2 yr^?1) were consistent with those reported in 1990–1991 and in other regions. However, changes in taxonomic composition were apparent with increases in the proportion of Acroporidae spat at some sites. Settlement of all taxa was highest over summer months, whereas during winter only one coral spat (Pocilloporidae) was detected. Coral settlement was highest and most taxonomically diverse at sites closest to the reef crest, where mortality of settled spat was also greatest. Rates of settlement were high compared with juvenile densities; hence, post-settlement mortality is also likely to be high. Post-settlement processes, influenced by local environmental conditions, are likely to be very important in structuring the adult coral communities within the LHI reef lagoon.     

珊瑚礁生态脆弱性评价--以泰国思仓岛为例

珊瑚礁生态系统受到环境变化、人类活动等各种因素的严重威胁,保护珊瑚礁生态系统是目前全球海洋生态保护的热点,对珊瑚礁开展定量的生态脆弱性评估能够为保护管理对策的制定提供重要科学依据。本研究选取泰国思仓岛作为研究区域,结合空间分析技术建立了具有通用性的珊瑚礁生态脆弱性评估方法。基于ESA模型构建了珊瑚礁生态脆弱性综合指数和评价指标体系,系统分析了思仓岛珊瑚礁脆弱性的来源、构成,并直观展现了脆弱性的区域空间分布。结果表明:思仓岛研究区东北侧的珊瑚礁生态脆弱性大于西南侧,当地珊瑚礁的关键影响因子分别为驳船排污、港口码头、水体透明度等。根据脆弱性评价的结果,提出了当地珊瑚礁保护与修复的空间分区管理对策。本研究为印度-太平洋区系珊瑚礁生态脆弱性评价提供了可行的示例,也为中国的珊瑚礁可持续管理研究提供了借鉴和参照。     

Species composition and structure of coral community of a platform reef at Bach Long Vi Island in the South China Sea

A platform reef at Bach Long Vi Island (Gulf of Tonkin in the South China Sea) was investigated for the first time. In all, 264 species of corals and their accompanying species of macrobenthos were found. Among the scleractinian corals, acroporids, poritids, and mussids dominated. Monospecific aggregations of alcyonarians Sinularia and Lobophytum and the hydroid Millepora were rather numerous. Based on its geomorphological characteristics, coral species diversity and zonal distribution, the investigated reef is comparable with ribbon and platform reefs on the Great Barrier Reef in Australia and in the Indian Ocean.