Biomass and estimated production rates of metazoan zooplankton community in a tropical coral reef of Malaysia

Quantitative research on composition, biomass and production rates of zooplankton community is crucial to understand the trophic structure in coral reef pelagic ecosystems. In the present study, micro‐ (35–100 μm) and net‐ (>100 μm) metazooplankton were investigated in a fringing coral reef at Tioman Island of Malaysia. Sampling was done during the day and night in August and October 2004, and February and June 2005. The mean biomass of total metazooplankton (i.e. micro + net) was 3.42 ± 0.64 mg C·m^?3, ranging from 2.32 ± 0.75 mg C·m^?3 in October to 3.26 ± 1.77 mg C·m^?3 in August. The net‐zooplankton biomass exhibited a nocturnal increase from daytime at 131–264% due to the addition of both pelagic and reef‐associated zooplankton into the water column. The estimated daily production rates of the total metazooplankton community were on average 1.80 ± 0.57 mg C·m^?3·day^?1, but this increased to 2.51 ± 1.06 mg C·m^?3·day^?1 if house production of larvaceans was taken into account. Of the total production rate, the secondary and tertiary production rates were 2.20 ± 1.03 and 0.30 ± 0.06 mg C·m^?3·day^?1, respectively. We estimated the food requirements of zooplankton in order to examine the trophic structure of the pelagic ecosystem. The secondary production may not be satisfied by phytoplankton alone in the study area and the shortfall may be supplied by other organic sources such as detritus.     

SCUBA divers above the waterline: Using participatory mapping of coral reef conditions to inform reef management

Coral reefs provide important ecological services such as biodiversity, climate regulation, and cultural benefits through recreation and tourism. However, many of the world's reefs are declining, with Caribbean reefs suffering a significant decline in living corals over the past half century. This situation emphasizes the need to assess and monitor reef conditions using a variety of methods. In this study, a new method for assessing reef conditions to inform management using participatory mapping by coral reef “experts” in the U.S. Virgin Islands (USVI) is described. Occupational SCUBA divers were recruited (n=87) to map coral reef conditions, uses, and threats (stressors) using an internet-based mapping website. The data reveal an uneven geographic distribution of reef conditions in the USVI with the most frequently mapped perceived healthy reef characteristics being: large amount of physical reef structure (n=872 markers); endangered or threatened species present (n=721); and large amount of live coral cover (n=615). The greatest perceived threats were: invasive species (n=606); water pollution (n=234); and unsustainable fishing (n=200). Areas of important reef characteristics, perceived threats to reefs, and perceived recovery potential were plotted to identify areas requiring critical management attention. The authors found that perceptions of healthy reef conditions outnumbered perceptions of reef threats for nine of the ten most familiar coral reefs; the most frequent activity type within the coral reefs was tourism diving; and for the most familiar coral reefs, the divers perceived a high recovery potential. Given the novelty of participatory mapping methods to assess coral reefs, the strengths and weaknesses of the method is evaluated. The authors further propose a management typology for categorizing reef areas to inform their future management. In the absence of primary data, or, as a supplement to underwater surveys and remotely-sensed data on reef condition, participatory mapping can provide a cost-effective means for assessing coral reef conditions while identifying place-specific reef locations requiring management attention.     

Mapping the global value and distribution of coral reef tourism

Global coral reef related tourism is one of the most significant examples of nature-based tourism from a single ecosystem. Coral reefs attract foreign and domestic visitors and generate revenues, including foreign exchange earnings, in over 100 countries and territories. Understanding the full value of coral reefs to tourism, and the spatial distribution of these values, provides an important incentive for sustainable reef management. In the current work, global data from multiple sources, including social media and crowd-sourced datasets, were used to estimate and map two distinct components of reef value. The first component is local “reef-adjacent” value, an overarching term used to capture a range of indirect benefits from coral reefs, including provision of sandy beaches, sheltered water, food, and attractive views. The second component is “on-reef” value, directly associated with in-water activities such diving and snorkelling. Tourism values were estimated as a proportion of the total visits and spending by coastal tourists within 30 km of reefs (excluding urban areas). Reef-adjacent values were set as a fixed proportion of 10% of this expenditure. On-reef values were based on the relative abundance of dive-shops and underwater photos in different countries and territories. Maps of value assigned to specific coral reef locations show considerable spatial variability across distances of just a few kilometres. Some 30% of the world's reefs are of value in the tourism sector, with a total value estimated at nearly US$36 billion, or over 9% of all coastal tourism value in the world's coral reef countries.     

Spatio-temporal variability of benthic macroalgae in a coral reef system highly influenced by fluvial discharge: Veracruz,Gulf of Mexico

The Veracruz Reef System, in the southern Gulf of Mexico, is a suitable area for the study of the temporal and spatial variability of macroalgae abundance, at reef settings influenced by the fluvial discharge of the Jamapa River, and by human activities in the city and port of Veracruz. With this purpose, the bottom cover of each morpho-functional group of benthic macroalgae (frondoses, turf, and crustose corallines), and hermatypic corals, was determined at ten selected coral reefs, on a seasonal basis (rainy and dry seasons), for the 2009–2015 period. The average cover of benthic macroalgae was high (53.1%), with turf as the dominant morpho-functional group (31.9%), as in several reef ecosystems in the tropical Atlantic, followed by crustose corallines (15.2%), and frondoses (6.1%). Although turf macroalgae is dominant, due to their high temporal and spatial variability, the Veracruz Reef System could not be considered to be in a stable state, but just in an intermediate unstable equilibrium state, which is highly influenced by a high sediment load. As expected, nearshore reefs presented higher macroalgae covers, and unexpectedly, the outer-shelf reefs presented the highest cover of frondoses. Despite fluvial discharge influence, no differences in cover were found between the rainy and dry seasons. There was a negative and significantly correlation between the cover of frondoses and turf, which suggests that the driver/s of the abundance of these macroalgae, act in opposite ways for each group. Three clusters of reefs, defined by community structure and conservation degree, were determined: nearshore or degraded, offshore or moderately conserved, and conserved; and the entire Veracruz Reef System is considered to be in a moderately state of conservation.     

Biodiversity,ecological structure,and change in the sponge community of different geomorphological zones of the barrier fore reef at Carrie Bow Cay,Belize

Changes in the relative abundance of benthic groups on the barrier fore reef at Carrie Bow Cay, Belize, point to a significant reduction of corals and an expansion of the sponge community in 1995–2009. Fifty‐one species are now present in the four geomorphological zones of this reef: the low‐relief spur‐and‐groove zone, the inner reef slope, the outer ridge, and the fore‐reef slope (to a depth of 30 m). Five species are new additions to the sponge fauna reported for Belize, and six species account for 42.6% of the total assemblage: Niphates erecta (9.60%), Aiolochroia crassa (8.8%), Niphates digitalis (6.9%), Callyspongia plicifera (6.63%), Aplysina archeri (5.37%) and Xestospongia muta (5.37%). Species richness, average density, diversity and evenness indexes are statistically similar in these four zones but some species appear to be more dominant in certain areas. In the same 30 years, coral cover has decreased by more than 90%, while the octocoral cover has greatly increased (by as much as 10‐fold in the low‐relief spur‐and‐groove zone). Thus the Carrie Bow fore reef appears to be undergoing a transition from coral dominance in the late 1970s to algae dominance today, with other benthic groups such as sponges and octocorals showing signs of gradual recovery.     

Evidence of a phase shift to Epizoanthus gabrieli Carlgreen, 1951 (Order Zoanthidea) and loss of coral cover on reefs in the Southwest Atlantic

There is at present a ‘coral reef crisis’; one of the more drastic consequences of this is a phase shift, in which reef‐building corals are replaced by non‐reef building benthos such as macroalgae and soft corals. Previous studies have principally focused on the shift to macroalgae. Our goal was to investigate whether the dominance of the zoanthid Epizoanthus gabrieli on some reefs of Todos os Santos Bay, Brazil, represented a non‐algal phase shift. In 2003, we identified a high cover of this species on two reefs (52% and 70%), but only in 2007 was it possible to confirm a reduction in coral cover. This dominance has persisted for over 9 years, characterizing a true phase shift. This loss of coral cover may be a result of anthropogenic disturbances within the bay; however, given the large number of human impacts, further studies are needed to identify specific causes of this shift. Although there are some reports of phase shift involving species pertaining to the Class Anthozoa, this is the first report of this phenomenon involving the order Zoanthidea.     

Spatial discordance in fish,coral, and sponge assemblages across a Caribbean atoll reef gradient

Certain biodiversity patterns on coral reefs are generally consistent but we still lack fundamental insight into how assemblages vary across spatially heterogeneous reef systems. We compared fish, coral, and sponge assemblages across a symmetrical physiographical gradient (windward forereef, lagoon patch reef, leeward forereef) of the Glover's Reef atoll, Belize. Species richness of fishes and corals was highest in the deep habitat (15 m) on the windward forereef. Sponges were diverse and abundant on both deep windward and leeward forereefs but not on the exposed shallow (5 m) windward forereef. Fish and benthic assemblages were relatively distinct in each reef zone, with the lagoon patch reef communities consisting of a combination of leeward and windward species. Nevertheless, there were no clear patterns in community similarity matrices of fish and benthic assemblages, suggesting that overall coral and sponge assemblages had weak or no direct association with patterns in fish assemblages. A closer examination of fish trophic groups indicated that planktivores and predators were predictably associated with depth, whereas herbivores were associated with shallow protected reefs. None was specifically associated with spatial location along the atoll gradient. These patterns of diversity distribution are important for identifying spatial conservation priorities. A Marine Protected Area (MPA) at Glover's Reef encompasses substantial windward forereef and patch reef habitats. A much lesser extent of protection is afforded the leeward forereef that supports faunal assemblages that are unique and productive, if not as diverse as the windward forereef. Isolated coral atolls can serve as ideal systems to study spatial heterogeneity and biodiversity patterns, but more experimental studies are needed to reveal the mechanistic processes underlying these patterns.     

Evaluating the influence of candidate terrestrial protected areas on coral reef condition in Fiji

In any given region, there are multiple options for terrestrial protected area networks that achieve goals for conservation of terrestrial biodiversity and ecosystem values. When deciding on the location of terrestrial protected areas, planners typically focus only on terrestrial conservation goals, ignoring potential linked benefits to marine ecosystems. These benefits include maintenance of downstream water quality, as forest protection can prevent changes in amount and composition of river runoff that negatively impacts coral reefs. This study aims to determine the benefit of different terrestrial reserve networks to the condition of coral reefs adjacent to the main islands of Fiji to support the work of Fiji's Protected Area Committee in expanding the national protected area estate through integrated land–sea planning. Options for terrestrial protected area networks were designed using six approaches, where the primary objective of each approach was to either achieve terrestrial conservation goals (e.g., represent 40% of each vegetation type) or maximize benefits to coral reefs by minimizing potential for land-based runoff. When achieving terrestrial conservation goals was the primary objective, the potential benefits to coral reef condition were 7.7–10.4% greater than benefits from the existing network of protected areas. When benefiting reefs was the primary objective, benefits to coral reefs were 1.1–2.8 times greater per unit area than networks designed to only achieve terrestrial conservation goals, but 31–44% of the terrestrial conservation goals were not achieved. These results are already being used by Fiji's Protected Area Committee to modify the boundaries of existing priority places to deliver outcomes that better meet terrestrial conservation goals while offering greater benefits to coral reef condition through prevention of run-off.     

How U.S. ocean policy and market power can reform the coral reef wildlife trade

As the world’s largest importer of marine ornamental species for the aquaria, curio, home décor, and jewelry industries, the United States has an opportunity to leverage its considerable market power to promote more sustainable trade and reduce the effects of ornamental trade stress on coral reefs worldwide. Evidence indicates that collection of some coral reef animals for these trades has caused virtual elimination of local populations, major changes in age structure, and promotion of collection practices that destroy reef habitats. Management and enforcement of collection activities in major source countries such as Indonesia and the Philippines remain weak. Strengthening US trade laws and enforcement capabilities combined with increasing consumer and industry demand for responsible conservation can create strong incentives for improving management in source countries. This is particularly important in light of the March 2010 failure of the parties to the Convention on International Trade in Endangered Species (CITES) to take action on key groups of corals.     

Temporal variation of ophiuroids associated with the macroalga Amphiroa fragilissima on a Southwest Atlantic coral reef

The species of Ophiuroidea that commonly occur on coral reefs can be found on different substrates and associated with other organisms including algae, sponges, and corals. This study evaluated the temporal variability of the ophiuroid fauna associated with the alga Amphiroa fragilissima on the Ponta Verde coral reef on the coast of Maceió in Alagoas, Northeastern Brazil. Replicate samples of algal substrate were collected at low tide during in the dry and rainy seasons, over a 10‐year period, from 1998–2007. Eight species of Ophiuroidea were identified, with a total of 8736 individuals associated with A. fragilissima. The most dominant and frequent species of Ophiuroidea were Amphipholis squamata and Ophiactis savignyi; all other species were rare. Cluster analysis and nMDS detected four groups, with two groups each occurring only in summer or winter periods, as well as other groups occurring in both periods.     

人工采掘坑影响下珊瑚礁海岸波浪传播变形试验

基于礁坪上高分辨率的波浪测量,通过波浪水槽试验分析了短波、低频长波、平均水位、波形参数和非线性参数的沿礁变化规律,重点探讨礁坪中部存在人工采掘坑对上述波浪传播变形特征的影响,并与无坑的情况进行对比.研究表明:当人工采掘坑存在时,短波波高在坑前和坑内分别增大和减小,在礁后岸滩附近却无显著变化;低频长波波高在坑附近变化不大...     

Spatial distribution of crustaceans associated with shallow soft‐bottom habitats in a coral reef lagoon

The ecology and diversity of the shallow soft‐bottom areas adjacent to coral reefs are still poorly known. To date, the few studies conducted in these habitats dealing with macroinvertebrate fauna have focused on their abundance spatial patterns at high taxonomic levels. Thus, some aspects important to evaluate the importance and vulnerability of these habitats, such as species diversity or the degree of habitat specialization, have often been overlooked. In this study we compared the crustacean assemblages present in four different habitats at Magoodhoo Island coral reef lagoon (Maldives): coral rubble, sandy areas and two different seagrass species (Thalassia hemprichii and Cymodocea sp.). Forty‐two different crustacean species belonging to 30 families and four orders were found. ‘Site’ was a significant factor in all of the statistical analyses, indicating that tropical soft‐bottom habitats can be highly heterogeneous, even at a spatial scale between tens and hundreds of meters. Although traditionally it has been considered that seagrass beds host greater species diversity and abundance of organisms than adjacent unvegetated habitats, no differences in the univariate measures of fauna (abundance of organisms, number of species and Shannon diversity) were observed among habitats. However, sandy areas, coral rubble and seagrass beds exhibited different species composition of crustacean communities. The percentage of taxa considered as potential habitat specialists was 27% and the number of species exclusively occurring in one habitat was especially high in seagrass beds. Thus, degradation of this vegetated habitat would result in a great loss of biodiversity in tropical shallow soft‐bottom habitats.     

全球变化背景下暖水珊瑚礁生态系统的适应性与修复研究

暖水珊瑚礁生态系统是热带海域最具生物多样性和代表性的生态系统之一。本研究分析了全球变化背景下暖水珊瑚礁生态系统的变化和风险,开展了受损暖水珊瑚礁生态系统退化和消失的致灾因子归因分析,综述了暖水珊瑚礁生态系统的适应性与修复技术研究。分析表明:①过去几十年来,暖水珊瑚礁生态系统快速退化,包括大面积白化和死亡、多样性明显减少和生态功能显著衰退,主要归因于海洋升温与人类活动等致灾因子的影响;②在温室气体高排放浓度情景下(RCP 8.5),相比工业革命前,到本世纪中叶,南海升温将可能远超过2℃,这表明南海暖水珊瑚礁生态系统正在逼近其气候临界点,即全球升温高于2℃时,90%~99%以上的暖水珊瑚将消失;③1980年代以来,海洋升温、海洋热浪和强热带气旋等海洋气候变化致灾因子对南海暖水珊瑚的危害性(影响的强度、范围和时间)明显增加,对暖水珊瑚礁生态系统产生了严重的影响;与此同时,近岸海域的过度或破坏性捕捞、采挖和潜水等人类活动,对暖水珊瑚造成了严重损害,增加了暖水珊瑚的气候脆弱性,而这种人类活动既是局部的,也是全球性的现象,使得暖水珊瑚更难以适应全球变暖的影响。分析还表明,为了增强暖水珊瑚适应气候与环境变化的恢复力(韧性),人们开展了诸多受损珊瑚礁生态系统的适应性与修复研究,但主要是采用无性繁殖或结合人工基质的修复方式,而应用有性繁殖技术恢复受损珊瑚礁的方式仍较少;最近,暖水珊瑚耐热的基因适应性研究取得了重要进展,为暖水珊瑚适应全球变暖提供了一种新的途径。本研究最后探讨了中国受损珊瑚礁生态系统的修复问题与对策。     

Construction and analysis of a coral reef trophic network for Qilianyu Islands,Xisha Islands

Qilianyu Islands coral reefs (QICR), located in the northeastern part of the South China Sea, has been affected by human activities and natural disturbance. To characterize the trophic structure, ecosystem properties and keystone species of this region, a food-web model for the QICR is developed using methods involving a mass-balance approach with Ecopath with Ecosim software. Trophic levels range from 1.00 for detritus and primary producers to 3.80 for chondrichthyes. The mean trophic transfer efficiency for the entire ecosystem is 13.15%, with 55% of total energy flow originating from primary producers. A mixed trophic impact analysis indicates that coral strongly impacts most components of this ecosystem. A comparison of our QICR model with that for other coral reef ecosystems suggests that the QICR ecosystem is immature and/or is degraded.     

亚热带沿海景观的旅游保护性开发及建设探讨--以福建沿海为例

依据地貌学和风景学的角度,福建沿海景观以闽江口和九龙江口为界可分为3个景观亚区,并具有多样性与复杂性、动态性与脆弱性和关联性与分异性等特征.本文运用景观生态的原理研究沿海景观的构成与格局,在沿海景观的分类和特征概括的基础上,探讨福建沿海景观旅游开发与建设的模式.通过维护沿海景观系统的稳定,优化沿海各景观亚区的分布格局,提高沿海景观的整体舒适性和挖掘文化景观的内涵等应对措施以实现福建沿海旅游的科学发展.     

A new coral reef province in the Gulf of Carpentaria, Australia: Colonisation, growth and submergence during the early Holocene

Multibeam sonar mapping, drill cores and underwater video data have confirmed the existence of a previously unknown coral reef province in the Gulf of Carpentaria, Australia. Seven reefs, comprised of coral limestone that support living corals have been mapped so far and as many as 50 other reefs may exist in the region. U/Th ages show that reef growth commenced shortly after limestone pedestals were submerged by rising sea level around 10.5 kyr BP, making them the oldest Holocene reefs known in Australia. Reef growth persisted for ~ 2.0 kyr but it had ceased at most locations by ~ 7.0 kyr BP. Measurements of reef growth rates (0.95 to 4 m kyr^− 1), indicate that the reefs were unable to keep pace with contemporaneous rapid sea level rise (> 10 m kyr^− 1), which is consistent with a “give up” reef growth history. Core samples from reef platforms demonstrate that Pleistocene limestone is exposed at depths of 27 and 30 m below present mean sea level. These depths represent regionally significant phases of reef growth during a prolonged sea level still stand. We conclude that the reefs are therefore mostly relict features, whose major phase of growth and development relates to an earlier, pre-Holocene sea level still stand.     

Water-level fluctuations, emersion regimes, and variations of echinoid populations on a Caribbean reef flat

This paper examines fluctuations in water level over a Caribbean reef flat at Punta Galeta, Panamá. In an analysis of approximately ten years of records, the mean diurnal range of the tides was 24·5 cm and varied <2 cm from year to year. Daily mean water levels varied erratically over a range of approximately 30 cm. Monthly mean water levels fluctuated seasonally over a range of about 10 cm and were consistently higher than those at the regional tidal reference station at Cristóbal. On days with more wave action, water levels at Galeta increased relative to those at Cristóbal, suggesting that waves were ‘pumping’ water onto the reef flat. The monthly mean water levels at the two sites were not correlated, indicating that tidal data from conventional stations in deeper water cannot be extrapolated to reef flats, except as estimates of minimum potential water levels.Most of the reef flat was within 6 cm vertical span just below mean lower low water. The highest elevations within this range were exposed above water level for an average of 918 hours per year, as compared with 144 hours per year at the lowest elevation. Most exposures lasted less than 10 hours, with a modal duration of 3–5 hours; however, exposures longer than 12 hours occurred at nearly all elevations in all years. Exposures of the reef flat were most frequent between February and June and between August and November, a pattern apparently caused by a combination of seasonal oscillations of regional sea levels, the annual pattern of the solstitial tides, and waves generated by seasonal trade winds.The fluctuations in water levels apparently affected the abundances of some species of sea urchins on the reef flat. Populations of Lytechinus variegatus and Diadema antillarum declined or disappeared from the reef flat during seasons of repeated subaerial exposures, but recolonized the habitat in periods of higher water levels. Although they are reported to suffer heavy mortality during emersion, Echinometra lucunter and E. viridis did not exhibit reductions in abundance that were synchronous with the seasonal exposures of the reef flat.     

Redundancy and diversity of functional reef fish groups of the Mexican Eastern Pacific

Coral reefs are in crisis worldwide. Fish play a key role in the resilience of reefs because most of the biomass of the ecosystem flows through them. Evidence indicates that the response to stressors will vary markedly depending on the resilience of the ecosystem. In order to assess the functional groups of reef fishes, morphometric and ecomorphological analyses were carried out on the shape and diet of 117 reef fish species from the Mexican Eastern Pacific (MEP) from 23°N to 15°N, spanning the years 2009–2012. Six trophic groups were identified and subdivided into 19 functional groups: (A) detritus and plants consumers, three morphologies; (B) plants and zoobenthos consumers, four morphologies; (C) zoobenthos consumers, two morphologies; (D) zoobenthos and zooplankton consumers, three morphologies; (E) zooplankton and nekton consumers, three morphologies; and (F) nekton consumers, four morphologies. Our main conclusions are: (i) fish communities of the MEP have a high degree of ecological redundancy; (ii) fish diversity is not related to the coral cover; and (iii) the combination of using both morphology and diet produce a more effective classification of functional groups. Future studies such as these will allow a deeper understanding of environment and it will help illuminate the effects of fish morphology and diet on population structure.     

基于PSR模型的珊瑚礁生态系统健康评价指标体系的构建与应用

运用压力-状态-响应（pressure-state-response,PSR）模型,采用生态系统健康理论评价珊瑚礁生态状况.借鉴国内外现有生态系统评价方法,结合珊瑚礁生态系统的特点,建立适合我国国情的珊瑚礁生态系统评价方法和模式,并对我国典型海域珊瑚礁生态健康状况进行评价,以期为我国典型珊瑚礁生态系统健康状况提供基础资料.评价结果显示东山、涠洲岛、海南东部珊瑚礁生态健康状况为健康,徐闻和西沙海域珊瑚礁生态健康状况为亚健康,评价结果与我国相关生态监控区调查结果基本一致.     

Ecological assessments of the coral reef communities in the Eastern Caribbean and the effects of herbivory in influencing coral juvenile density and algal cover

Caribbean reefs have been unevenly surveyed, with many areas lacking baseline data. In this study, the current status of Orbicella reefs, a structurally complex forereef habitat, was quantified in an understudied region, the Eastern Caribbean. During 2011 the same observers surveyed benthic assemblages, coral juvenile density, herbivorous fishes, and invertebrates at 30 Orbicella reefs in four Eastern Caribbean areas: Antigua, Barbados, St Lucia, and St Vincent and the Grenadines (hereafter St Vincent). Not all Orbicella forereefs were functionally the same in the Eastern Caribbean. Benthic communities and herbivorous fishes varied greatly among islands. Hard coral had the highest overall percent cover on most reefs in this study, with an average cover of 22%, and was greater than fleshy macroalgal cover at 83% of the sites. Overall, coral juvenile density was low but was positively associated with higher densities of Diadema antillarum, highlighting the importance of herbivory on the reefs. Nearshore coral reefs in Barbados were in a better state than other areas, exhibiting higher coral cover dominated by spawning corals, higher densities of coral juveniles exhibiting higher coral cover dominated by spawning corals, higher densities of coral juveniles and D. antillarum. Low biomass of herbivorous fishes at a majority of the coral reef sites is of major concern for the functioning of these reefs. Conservation of parrotfishes and other herbivores is necessary given the abundance of algae on most of these reefs and the beneficial effect of their presence on coral juveniles. This is the first comprehensive study that compares the state of Orbicella reefs in the Eastern Caribbean, providing valuable information that will be useful in creating realistic targets for future management and conservation.