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1.
刘静  肖永双 《海洋与湖沼》2021,52(2):498-507
印太交汇区不仅是热带物理海洋海气能量汇聚中心、地质板块活跃中心以及生物多样性中心,而且也是用于开展地球系统物质能量交换与全球气候变化以及海洋生物多样性起源研究的理想靶区,因此一直受到世界科学家们的广泛关注。作为全球34个生物多样性热点区域之一,印太交汇区的珊瑚礁三角区孕育了全球76%的造礁珊瑚、75%的红树林、50%的珊瑚礁鱼类和45%的海草物种数。鱼类是珊瑚礁生态系统中最重要的组成部分之一,在整个印度-太平洋海域中珊瑚礁群落的组成和维持中起到重要作用。过去,生物学家们围绕热带珊瑚礁鱼类多样性格局与演化做了大量工作,提出了许多生物地理学假说模型,如中心物种形成模型、汇聚中心模型、重叠中心模型和华莱氏线假说等,这些假说在一些珊瑚礁鱼类类群得到验证。但是,相对于印太交汇区的热带珊瑚礁鱼类多样性研究,深海的鱼类区系和生物多样性研究起步较晚,仍缺乏时间序列的观测数据和系统研究。目前对于印太交汇区深海与浅海生物多样性中心形成演化机制以及深浅海生物之间的源汇关系认知方面仍存在分歧。本文梳理了过去国内外学者在印太交汇区鱼类多样性方面的研究工作,综述了该地区浅海热带珊瑚礁和深海鱼类多样性格局演化研究最新进展,提出在深海极端环境和生命过程研究对策,以期为探讨印太交汇区海洋生物多样性中心形成演化过程及证实/证伪各种生物地理学假说提出科学论据,并为战略生物资源开发利用提供新视角。  相似文献   

2.
应用Excel 软件计算生物多样性指数   总被引:14,自引:0,他引:14  
生物多样性指数是生物群落研究中的重要参数,广泛应用于海洋生态系统生物多样性的评价和研究。作者利用微软的电子表格软件Excel中的数组函数、条件函数及其他函数,提供了一种快速、简便、可靠的同时计算Shannon、Simpson、Berger-Parker、Margalef和Pielou均匀度指数等8种常用生物多样性指数的方法,应用开发的Excel文件——Biodixcel.xlsx,使用者只需在此文件列出的表格中一次性录入所要计算的原始数据即可在此表格中同时得到上述几个指数的计算结果,本方法为群落生物多样性的计算提供了一种简单、实用的工具。  相似文献   

3.
Large physical changes that alter reef macrobenthos and fish assemblages occur with increasing depth, so the biological processes that regulate communities at different depths are expected to diverge. We used analyses of stable isotopes (δ13C and δ15N) and fatty acids to establish whether shallow (11–25 m) and deep (45–75 m) warm-temperate reef communities within a South African marine protected area differ in their trophic organisation and nutritional condition. We found evidence of enhanced nutritional condition in plankton from the deeper reef as compared with the shallow reef based on the essential fatty acid content, but this effect was generally not observed in the macrobenthos or the fish communities. Community-based indices derived from the stable isotope data indicated that the shallow-reef community had significantly greater niche diversification (greater diversity of carbon sources at the base of the food web) and more niche space occupied than the deep-reef community. One obvious difference in available carbon sources between reef communities was the absence of benthic primary production on the deep reef, where light is limiting. Our results highlight that the decreased trophic diversity, and to an extent functional redundancy, associated with the simplification of food webs at depth may translate into greater vulnerability of deep reefs to disturbance.  相似文献   

4.
The use of artificial reefs in the Arabian Gulf have a history extending back over a century, when date palm trunks, stones, pottery and other materials were sunk in coastal areas to enhance fish catch. Historically, such artificial reefs formed an important component of the socio-economic development of coastal fisheries. In comparison, modern artificial reefs have taken on a variety of forms. The most widely recognized are purpose-build modular artificial reefs designed for the enhancement of fisheries yield, diving, and various other benefits. However, far more common within the Gulf are the large-scale unplanned artificial reefs that have been formed as a result of human activities in the marine system, such as large-scale coastal breakwaters, seawalls, jetties, pipelines, and oil and gas infrastructure. Although there is limited information on the role of these constructions in structuring Gulf marine communities, increasing evidence suggests that abundant and diverse communities of reef fish, coral and other benthos can develop on these structures, with important ecological implications in urbanized coastal areas in the Gulf. However, due to a variety of unintended consequences of artificial reef development such structures may also pose challenges to coastal marine management. We review the current published literature on artificial reefs in the Gulf in order to improve our understanding of the role that these structures play in Gulf coastal ecosystems, and to further develop regional management of artificial reefs. We explore the various types of artificial reef that exist in the Gulf and examine the benefits and challenges that these structures represent for coastal ecology and economics. Such information is essential for our improved understanding and management of these increasingly important ecosystems in the Gulf.  相似文献   

5.
Eutrophication from a variety of anthropogenic sources is an increasingly prevalent problem in coastal waters, and is one of the factors contributing to the decline of seagrass ecosystems worldwide. This study investigated the impact of natural nutrient enrichment derived from nesting seabird colonies on Man O'War Cay, Belize, on the epiphytic foraminiferal communities living on the seagrass Thalasssia testudinum. Man O'War Cay, a small mangrove island in the central region of the barrier reef complex, hosts nesting colonies of magnificent frigate birds and brown boobies. Epiphytic foraminiferans were surveyed from five stations spaced at 10‐m intervals along a 40‐m transect in a seagrass meadow located off the eastern end of the island (March 2004). Low species diversity and high dominance of the encrusting, dendritic species Cornuspiramia antillarum characterized the epiphytic foraminiferal biota. Species diversity, as measured by the Shannon's H, and evenness, as measured by Buzas–Gibson's E, decreased in an offshore direction. The density of individuals per square centimeter of blade, however, increased in an offshore direction, with the lowest values observed at the station closest to the island, and the highest values recorded at the station farthest from the shore. The results obtained in this study indicate that epiphytic foraminiferal populations respond to nutrient enrichment, and thus may be useful indicators of ecosystem decline in subtropical–tropical, oligotrophic marine habitats.  相似文献   

6.
Deep-sea ecosystems are fragile yet diverse habitats that are sensitive to disturbance. In the northern Gulf of Mexico deepwater extraction of hydrocarbons led to the accidental release of four million barrels of oil from the Macondo wellhead in 2010. The release of oil combined with the addition of dispersant at depth and the resulting delivery of oiled “marine snow” led to dramatic disruptions of diversity and ecosystem services within the near field deep-sea benthic communities. Analysis of the biological trait diversity of the surrounding megabenthos reveals notable loss of traits that may explain the stunted recovery of communities within 2 km of the wellhead. The present megafauna show complete loss of some traits relating to tier, motility, and feeding mechanisms. Functional evenness was higher than in surveyed unaffected sites, highlighting some loss of trait space, reflecting increasing abundances of scavengers and the loss of sessile invertebrates. Loss of biological traits that aid in ecosystem resilience has impeded recovery of benthic communities severely impacted by the Deepwater Horizon oil spill.  相似文献   

7.
In consideration of the rapid degradation of coral reef ecosystems, the establishment of models is helpful to comprehend the degradation mechanism of coral reef ecosystems and predict the development process of coral reef communities. According to the characteristics of complex ecosystem of tropical coral reefs in China, the coral reef functional group is the core level variable; combined with the multiple feedback effects of coral reef functional groups and environmental changes, the study presents a coral reef ecosystem dynamics model with hermatypic corals as the core. Based on the simulation of the assumed initial value and the internal feedback of the system, the results show that in the basic simulation(relative health conditions), the coverage area of live corals and coral reefs generally decreased first and then increased, and increased by 4.67% and 6.38% between2010 and 2050, respectively. Based on the calibration model and the current situation of the studied area, the multi-factor disturbance effects of coral reef communities were simulated and explored by setting up three scenarios involving fishing policy, terrestrial deposition, and inorganic nitrogen emissions. Among them, in the single factor disturbance, the fishing policy exerts the most direct impact on the community decline; and the succession phenomenon is obvious; the terrestrial sedimentation has a faster and more integrated effect on the community decline; the effect of inorganic nitrogen emission on the community decline is relatively slow. In the double/multi-factor disturbance, the superimposed disturbance will aggravate the multi-source feedback effect of the coral reef communities development, accelerate the community decay rate, and make its development trajectory more complicated and diverse. This method provides a scientific and feasible method for simulating the damage of long-term coral reef community and exploring the development law and adaptive management of coral reef ecosystems. In the future, it can be further studied in the ecological restoration process and decisionmaking direction of coral reefs.  相似文献   

8.
Marine sediments in continental shelf ecosystems harbor a rich biodiversity of benthic communities. In this study, the spatial and temporal diversity and community assemblages of free‐living marine nematodes were studied by sampling at six depths and over 3 years from the southwest continental shelf off Bay of Bengal, one of the least explored tropical shelf ecosystems. The dominant marine nematode species were related with abiotic variables as part of this study. The effects of sediment granulometry generally decreased with increasing depth and the highest nematode density and species diversity were recorded on coarse sand (shallower depths). Multivariate analysis of the nematode community data showed that community structure differed significantly among depths as well as among years. Statistical analyses showed significant correlations between the nematode community and abiotic variables. Sediment texture, organic matter, water pressure and depth profile were crucial factors for determining diversity, vertical profile and feeding types of the nematode community. Other environmental factors, including anthropogenic pressure, did not have an effect on nematode diversity except for the presence of some tolerant species (Metachromadora spp., Sabatieria spp. and Siplophorella sp.). This study represents a baseline of knowledge of free‐living marine nematode communities that can be used in the future to compare nematode assemblages from temperate shelf ecosystems.  相似文献   

9.
象山港海洋牧场示范区大型底栖生物的时空变化   总被引:3,自引:0,他引:3  
根据象山港海洋牧场示范区建设前(2011年)、建设中(2012年)、建设后(2013年)对象山港全港区、邻近区、示范区11个站位,进行5个航次调查所获得的大型底栖生物的资料,对比分析建设前后大型底栖生物的时空变化。结果表明:共鉴定出大型底栖生物59种,建设后建设中建设前,优势种变化明显。大型底栖生物密度、生物量表现为:建设前建设中建设后;建设中建设后建设前。多样性指数H’、丰富度指数d均表现为:建设前建设后建设中,均匀度指数J则表现为建设中建设后建设前。多因子方差分析结果表明:建设前后,大型底栖生物种类数、栖息密度、生物多样性指数均存在显著性差异。根据群落聚类及n MDS排序分析,建设前后大型底栖生物群落组成存在明显差异,双因素相似性分析(ANOSIM)结果同时表明,群落建设前后存在显著性差异(综合检验R=0.215,P=0.004)。SIMPER分析,大型底栖生物群落的平均相似性建设前建设后建设中。根据调查站位的数据作出丰度/生物量比较曲线(ABC曲线)分析表明,建设中大型底栖生物受到了强烈的干扰,人工鱼礁投放、大型海藻移植、增殖放流会对其周围海域产生影响,但建设后扰动消失,表明随着时间的推移,海洋牧场建设过程中带来的扰动逐渐减小,并围绕鱼礁群逐渐形成新的人工生态系统。  相似文献   

10.
Despite the wide range of functional roles performed by marine sponges they are still poorly represented in many research, monitoring and conservation programmes. The aim of this review is to examine recent developments in our understanding of sponge functional roles in tropical, temperate and polar ecosystems. Functions have been categorised into three areas: (a) impacts on substrate (including bioerosion, reef creation, and substrate stabilisation, consolidation and regeneration); (b) bentho-pelagic coupling (including carbon cycling, silicon cycling, oxygen depletion and nitrogen cycling); and (c) associations with other organisms (facilitating primary production, secondary production, provision of microhabitat, enhanced predation protection, survival success, range expansions and camouflage though association with sponges, sponges as a settlement substrate, disrupting near-boundary and reef level flow regimes, sponges as agents of biological disturbance, sponges as releasers of chemicals and sponges as tools for other organisms). The importance of sponges on substrate, sponge bentho-pelagic coupling, and sponge interactions and associations is described. Although the scientific evidence strongly supports the significance and widespread nature of these functional roles sponges still remain underappreciated in marine systems.  相似文献   

11.
Coral reefs are vital to the livelihood of coastal communities in Quintana Roo, México and the preservation of these ecosystems relies on the establishment of protected areas. Education should be one of the most important management tools in coral reef preservation. Surveys were made among primary and secondary school students of Quintana Roo to determine the level of education regarding coral reefs and their importance. Students had little awareness about reefs. Coverage of coral reef issues is insufficient in school curricula and information media. Many students will leave school and become users of the reef with little understanding of it and of the consequences of exploitation of the reef. Creation of marine parks has not increased education and public awareness. There is an immediate need to establish appropriate and continuously available educational programs in order to preserve coral reefs. Education should encourage codes of behavior and community support to management issues.  相似文献   

12.
Management of tropical reef ecosystems under pressure from terrestrial and extractive marine activities is not straightforward, especially when the interests of extractive and non-extractive marine resource sectors compete. Before implementing management actions, potential outcomes of alternative management strategies can be evaluated in order to avoid adverse or unintended consequences. In tropical reef ecosystems the continued existence of the cultural and recreational fishing activities and the economically important dive-based tourism and recreation industry rest on sustainably managed marine resources. Through a case study of Guam, an ecosystem model was linked with human behavior models for participation in fishing and diving to evaluate future socio-ecological impacts of different management options. Ecosystem indices for reef status and resilience, and extraction potential were identified to evaluate the performance of alternative management scenarios. These marine ecosystem indices link the natural system to human uses (fishing and dive-based tourism and recreation). Evaluating management scenarios indicate that applying a single management tool, such as input controls or marine preserves, without also managing the watershed, is suboptimal. Combining different management tools has negative near-term costs, particularly for the fishing sector, but these are likely to be outweighed by the long-term benefits obtained from greater species abundance. Adopting watershed management measures in addition to fishery regulations distributes the burden for improving the reef status across multiple sectors that contribute to reef pressures.  相似文献   

13.
Distinctions are rarely made between vertical and horizontal surfaces when assessing reef community composition, yet physical differences are expected because of hydrodynamic differences and sediment accumulation on flat surfaces. As sand often diminishes biotic cover, we hypothesised that vertical surfaces will support a greater biomass but have lower diversity due to domination by a few species. To test this, we quantified sessile communities on vertical and horizontal surfaces at three sites in the Delagoa Bioregion on the east coast of South Africa. Community composition consistently differed: vertical communities were dominated by various filter feeders, especially the ascidian Pyura stolonifera, whereas those on horizontal reef comprised a mixture of filter feeders and various algae. The total number of species and all diversity metrics were significantly greater for horizontal reef surfaces. Contrastingly, Simpson’s dominance and biomass were significantly greater for vertical reef surfaces. Percentage cover of sand explained much of the variation in community composition whereas depth did not. Small-scale topographic differences in substratum orientation associated with differences in sand inundation will therefore influence both α and β diversity. Coastal developments and activities that alter sand movements and delivery to the coastal zone are therefore likely to have a profound influence on the maintenance and diversity of shallow subtidal communities.  相似文献   

14.
While ocean acidification (OA) poses a significant threat to ocean-related ecosystems and communities reliant on marine fisheries, aquaculture, and coral reef systems, limited public understanding and awareness can prevent coastal regions from being able to adequately assess the need for OA adaptation or mitigation. This study assessed public understanding of OA and how social and demographic factors influence the public’s concern for OA. The analysis was based on 311 questionnaires from full-time Alaska residents. The results showed that most Alaskans self-reported to have a basic awareness of OA, and subsequently were able to recognize that CO2 emissions related to human activity are the dominant driver of changing ocean conditions. However, there was a low recognition of how natural variability in the marine environment affects OA, and most respondents were not very confident in their understanding of OA-related science. Moreover, even though many communities in Alaska are reliant on commercial and subsistence fishing activities, the respondents had a low awareness of fisheries-related OA risk. Given the ongoing debate associated with climate change research, evaluating CO2 mitigation efforts through the perspective of OA could give individuals an unbiased way to assess the pros and cons of more intensive efforts to curb CO2 emissions. Furthermore, using OA communication to enhance the understanding of how natural variability influences OA around the state and the potential economic implications for Alaska fisheries would help residents and stakeholders make informed decisions when considering fisheries management plans, food security, and job diversity as OA intensifies. Solidifying the understanding that any reduction in pH and intensification of OA can have implications for marine species that are irreversible on human timescales will reinforce not only that OA is an immediate concern, but also the importance of taking action now.  相似文献   

15.
国际海洋浮游动物研究进展   总被引:7,自引:1,他引:6  
综述了国际上有关海洋浮游动物种群、群落结构、多样性及浮游动物对全球气候变化响应等方面研究进展。海洋浮游动物种类繁多, 数量丰富, 分布广泛, 是海洋生态系统中最重要的生物类群。在海洋食物网中, 浮游动物通过摄食浮游植物控制初级生产力, 同时, 又被更高营养阶层的动物(鱼、虾、鲸、海鸟等)捕食, 充当次级生产者的角色, 其群落结构、种群动态和物种多样性影响鱼类和其他海洋动物资源量, 浮游动物是海洋食物网中关键环节。海洋生态系统动力学过程的关键环节是浮游生物的生物学和生态学过程, 多项国际研究计划以生物多样性和年际变化趋势为研究重点并联系全球变化及响应, 因此, 浮游动物的研究已成为海洋生态研究的核心内容之一。国际上对浮游动物的研究主要集中在以下6个方向:(1)浮游动物生境、种群的分布和扩散动力学研究;(2)浮游动物的群落结构和多样性;(3)浮游动物的实验生态和现场受控生态研究;(4)浮游动物对全球气候变化的响应;(5)深海、南北极、低氧区等极端生境的浮游动物生态学研究;(6)浮游动物研究新技术和方法。  相似文献   

16.
Natural communities are constantly changing due to a variety of interacting external processes and the temporal occurrence and intensity of these processes can have important implications for the diversity and structure of marine sessile assemblages. In this study, we investigated the effects of temporal variation in a disturbance regime, as well as the specific timing of events within different regimes, on the composition and diversity of marine subtidal fouling assemblages. We did this in a multi‐factorial experiment using artificial settlement tiles deployed at two sites on the North East coast of England. We found that although there were significant effects of disturbances on the composition of assemblages, there were no effects of either the variation in the disturbance regime or the specific timing of events on the diversity or assemblage composition at either site. In contrast to recent implications we conclude that in marine fouling assemblages, the variability in disturbance regimes (as a driving force) is unimportant, while disturbance itself is an important force for structuring robust ecosystems.  相似文献   

17.
Most artificial reef (AR) studies have examined the early colonization stages of benthic communities, while only a few have monitored the development of AR communities beyond the initial successional phases and evaluated the time scale needed for such development. In addition, despite the proliferation of AR studies, comparative studies between artificial and natural reefs (NRs) are scarce. We present here the monitoring results of initial (1-2 year) and progressed (10 year) stages of the developing benthic communities of a purpose-planned AR submerged at Eilat, Israel (Red Sea), and compare them to its adjacent NR. Visual surveys of macro-invertebrates were conducted on the initial stages and coral communities were characterized at the progressed stage, using belt transects. The results demonstrate a distinct shift in species composition of the AR communities along the monitoring periods: from a soft coral dominated community, comprised mainly of Dendronephthya hemprichi, in initial developmental stages of up to two years post-deployment, to a community dominated by the sponge Crella cyatophora at year 10. Distinct differences in coral species count, living cover and diversity were found between the AR and its neighboring NR. We estimate the time frame required to develop a progressed diverse AR community to be well over a decade, even in tropical ecosystems. The factors shaping the species composition of purpose-designed ARs in a coral reef environment, including structural design, spatial orientation, depth and age, are discussed.  相似文献   

18.
本研究基于系统复杂性原理, 提出了南海典型珊瑚礁生态系统健康评价方法——组织力及系统功能评价法。该方法的评价框架包括珊瑚礁生态系统结构及功能、珊瑚礁生态系统与其他海洋生态系统间关系、与人类社会生态系统间关系、珊瑚礁生态系统发展制约因素等四大模块; 评价指标体系分为目标层、准则层、因素层、要素层等6个层级共计67个指标。同时, 本研究系统地提出了珊瑚礁生态系统健康评价的流程, 提高了珊瑚礁健康评价工作的规范性和时效性。应用组织力及系统功能评价法对2011—2018年西沙群岛珊瑚礁生态系统进行了健康评价, 结果显示自2011年起健康指数年均下降2.3%~2.4%, 除2012年、2015年健康指数稍有回升外, 其余年份均呈下降走势, 整体评价为亚健康状态。根据七连屿周边岛屿的实地考察和居民生活问卷调查结果, 2006—2008年的渔业发展、2012年的海星泛滥和2014—2015年的岛礁建设均对珊瑚礁生态系统造成了较大影响, 使10年内渔业产量下降了50%~80%。这与应用组织力及系统功能评价法的评价结果相吻合, 侧面验证了该评价方法的科学性和可行性。  相似文献   

19.
Understanding species distributions and their community structure is increasingly important when taking an ecosystem‐based approach to conservation and management. However, knowledge of the distribution and community structure of species in mid‐range trophic levels (e.g. macroinvertebrates) is lacking in most marine ecosystems. Our study aimed to examine the spatial distribution and community‐level biogeographic patterns of common kelp forest–rocky reef macroinvertebrates in Southern California and to evaluate the effects of environmental gradients on these communities. Quantitative SCUBA surveys were used to estimate macroinvertebrate densities at 92 sites from 2008–2012. Non‐metric multidimensional scaling was used to evaluate spatial patterns of macroinvertebrate communities among Regions. We found that kelp forest–rocky reef macroinvertebrate communities are distinct among different island and mainland regions, and their community patterns exhibited a strong relationship with an environmental gradient (i.e. sea surface temperature) even after controlling for geographic distance between sites. High abundances of urchin species (Strongylocentrotus purpuratus and Strongylocentrotus franciscanus) were strong drivers of regional differences. Macroinvertebrate community patterns were driven by characteristic species that were typically more prevalent at warmer or colder sites. Our results provide the first quantitative analysis of macroinvertebrate community structure within the California kelp forest ecosystem. We also describe the distribution and abundance of 92 conspicuous kelp forest‐rocky reef macroinvertebrates among nine pre‐defined Regions. This study provides important preliminary information on these macroinvertebrate species that will be directly useful to inform management of invertebrate fisheries and spatial protection of marine resources.  相似文献   

20.
Biodiversity estimations, particularly in vulnerable tropical regions, are essential to understanding ecosystem structure, function and conservation. While threats to marine and terrestrial ecosystems have fueled increased interest in biodiversity research, information on meiofauna, a key trophic and ecologic community of microscopic organisms that lives within sediments, is still lacking. Here we report the results of a faunistic investigation conducted in Bali, Indonesia. The results reveal that the biodiversity of marine meiofauna in Bali is very high. Meiofauna from coral reefs, sand flats and seagrass beds differed significantly in abundance and diversity. Nonetheless, overall community compositions show that meiofauna communities are affected by environmental variables. The high meiofaunal diversity observed in Bali, a low diversity region of the Coral Triangle, indicates the importance of further meiofaunal research across this region and across a broader diversity of habitats. The data presented provide an important baseline for future studies on biodiversity conservation in the face of environmental changes due to anthropogenic impacts and/or natural events.  相似文献   

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