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排序方式: 共有1072条查询结果,搜索用时 15 毫秒
221.
Mayara M. Silveira Jéssica Ferreira de Souza Ana L. Pires Moreira Priscila F. Silva Ana C. Luchiari 《Journal of fish biology》2019,95(3):772-780
We compared the memory of damselfish Stegastes fuscus in an aversive and appetitive conditioning task. Fish were trained to associate the sides of the tank that corresponded to the presence of a positive (conspecific presence) or negative (electroshock) stimulus. After two conditioning sessions, they were tested for learning. The fish conditioned to the stimulus were then re-tested for memory retention after 5, 10 or 15 days. Both the positive and negative rewards were associated with a specific side of the tank, indicating learning ability. Additionally, in both contexts, S. fuscus stored the information learned and showed similar behavioural patterns after 5, 10 and 15 days, suggesting long-lasting memory. For the ecological context, long lasting memories of social encounters outcomes and negative experiences of threatening situations may confer advantages that ultimately affect fishes’ fitness. 相似文献
222.
Elisa Bayraktarov Phoebe J. Stewart‐Sinclair Shantala Brisbane Lisa Bostrm‐Einarsson Megan I. Saunders Catherine E. Lovelock Hugh P. Possingham Peter J. Mumby Kerrie A. Wilson 《Restoration Ecology》2019,27(5):981-991
Coral reef restoration is an increasingly important part of tropical marine conservation. Information about what motivates coral reef restoration as well as its success and cost is not well understood but is needed to inform restoration decisions. We systematically review and synthesize data from mostly scientific studies published in peer‐reviewed and gray literature on the motivations for coral reef restoration, the variables measured, outcomes reported, the cost per hectare of the restoration project, the survival of restored corals, the duration of the project, and its overall spatial extent depending on the restoration technique employed. The main motivation to restore coral reefs for the projects assessed was to further our ecological knowledge and improve restoration techniques, with coral growth, productivity, and survival being the main variables measured. The median project cost was 400,000 US$/ha (2010 US$), ranging from 6,000 US$/ha for the nursery phase of coral gardening to 4,000,000 US$/ha for substrate addition to build an artificial reef. Restoration projects were mostly of short duration (1–2 years) and over small spatial extents (0.01 ha or 108 m2). Median reported survival of restored corals was 60.9%. Future research to survey practitioners who do not publish their discoveries would complement this work. Our findings and database provide critical data to inform future research in coral reef restoration. 相似文献
223.
Susan L. Williams Christine Sur Noel Janetski Jordan A. Hollarsmith Saipul Rapi Luke Barron Siobhan J. Heatwole Andi M. Yusuf Syafyudin Yusuf Jamaluddin Jompa Frank Mars 《Restoration Ecology》2019,27(2):447-456
The severely degraded condition of many coral reefs worldwide calls for active interventions to rehabilitate their physical and biological structure and function, in addition to effective management of fisheries and no‐take reserves. Rehabilitation efforts to stabilize reef substratum sufficiently to support coral growth have been limited in size. We documented a large coral reef rehabilitation in Indonesia aiming to restore ecosystem functions by increasing live coral cover on a reef severely damaged by blast fishing and coral mining. The project deployed small, modular, open structures to stabilize rubble and to support transplanted coral fragments. Between 2013 to 2015, approximately 11,000 structures covering 7,000 m2 were deployed over 2 ha of a reef at a cost of US$174,000. Live coral cover on the structures increased from less than 10% initially to greater than 60% depending on depth, deployment date and location, and disturbances. The mean live coral cover in the rehabilitation area in October 2017 was higher than reported for reefs in many other areas in the Coral Triangle, including marine protected areas, but lower than in the no‐take reference reef. At least 42 coral species were observed growing on the structures. Surprisingly, during the massive coral bleaching in other regions during the 2014–2016 El Niño–Southern Oscillation event, bleaching in the rehabilitation area was less than 5% cover despite warm water (≥30°C). This project demonstrates that coral rehabilitation is achievable over large scales where coral reefs have been severely damaged and are under continuous anthropogenic disturbances in warming waters. 相似文献
224.
Victor Shelamoff Cayne Layton Masayuki Tatsumi Matthew J. Cameron Jeffrey T. Wright Craig R. Johnson 《Restoration Ecology》2019,27(6):1442-1451
Ecosystem engineers are species that influence the abiotic and biotic environment around them and may assist the restoration of associated species, including other habitat‐forming species. We deployed an array of 28 artificial reefs with transplanted Ecklonia radiata, the dominant canopy‐forming kelp species across southern Australia, to investigate how the patch size and density of E. radiata influenced the establishment of the associated communities of plants and animals. Many of the reefs were rapidly colonized by Ostrea angasi, a critically depleted reef‐forming oyster. Over the 24‐month deployment of the reefs, thick oyster mats formed across the entire surface of many of the reefs with estimated biomass densities exceeding 5 kg of live oysters/m2; however, oyster density was dependent on E. radiata patch size and density. Increasing patch size and the presence of kelp resulted in significantly higher densities of oysters 5 months after the reefs were deployed and at the end of the experiment, where oysters were approximately three times more numerous on reefs with kelp compared to those without kelp. E. radiata appeared to facilitate the establishment of O. angasi largely through its capacity to reduce benthic light and thus suppress competition from turfing algae. These results may inform the development of novel approaches to tackle recruitment bottlenecks affecting the restoration of O. angasi reefs. 相似文献
225.
226.
Katherine P. Munkres Line K. Bay Dean R. Jerry Mark I. McCormick Lynne Van Herwerden 《Conservation Genetics》2007,8(4):987-990
Five new polymorphic microsatellite loci were developed for the coral reef damselfish Pomacentrus amboinensis. Twenty-four individuals from two Great Barrier Reef populations were genotyped at the five loci, with numbers of alleles
per locus ranging from 6–23 and observed heterozygosity between 0.42–0.92. In addition, the cross-species testing of six primers
developed for Stegastes partitus revealed one primer (SpGATA40) that was also polymorphic for P. amboinensis. Due to high levels of polymorphism (≥14 alleles) in at least four of the six loci and a high proportion of tetranucleotide
repeats, these microsatellite markers should be useful for parentage assignment as well as other investigations of individual
relatedness. 相似文献
227.
Spatially correlated recruitment of a marine predator and its prey shapes the large-scale pattern of density-dependent prey mortality 总被引:1,自引:0,他引:1
White JW 《Ecology letters》2007,10(11):1054-1065
Patterns of predator dispersal can be critical to the dynamics of prey metapopulations. In marine systems, oceanic currents may shape the dispersal of planktonic larvae of both predators and prey, producing spatial correlations in the recruitment of both species and distinctive geographic patterns of prey mortality. I examined the potential for this phenomenon in two fishes, a wrasse and its grouper predator, at a Caribbean island where the near-shore oceanographic regime produces a temporally consistent spatial pattern of fish recruitment. I found that recruitment and adult abundance of groupers were spatially correlated with recruitment of wrasse prey. Furthermore, the local abundance of predators strongly affected the nature of density-dependent prey mortality. At sites with few predators, wrasse mortality was inversely density-dependent, while mortality was positively density-dependent at sites with higher predator densities. This phenomenon could be important to the dynamics of any metacommunity in which physical forces produce correlated dispersal. 相似文献
228.
John N. Griffin Elizabeth C. Schrack Kemit‐Amon Lewis Iliana B. Baums Nicole Soomdat Brian R. Silliman 《Restoration Ecology》2015,23(3):197-200
Coral reef restoration aims to help threatened coral ecosystems recover from recent severe declines. Here we address whether coral fragments should be out‐planted individually or in larger aggregations. Theory suggests alternative possible outcomes: whereas out‐plants within aggregations might suffer from heightened negative interactions with neighbors (e.g. competition for space), they may alternatively benefit from positive interactions with neighbors (e.g. buffering wave disturbances). On a degraded reef in the Caribbean (St. Croix, USVI), using out‐plants of the critically endangered staghorn coral Acropora cervicornis, we experimentally tested how aggregation density (1–20 out‐planted coral fragments spaced at approximately 5 cm) influenced initial coral growth (over 3 months). Coral growth declined as a function of aggregation size, and out‐plants within larger aggregations had fewer and shorter secondary branches on average, indicative of horizontal competition for space. Our results therefore suggest that wide spacing of individuals will maximize the initial growth of out‐planted branching corals. 相似文献
229.
Sau Pinn Woo Zulfigar Yasin Shau Hwai Tan Hiroshi Kajihara Toshihiko Fujita 《ZooKeys》2015,(545):1-26
Five sea cucumber species including one new species of the genus Stichopus are reported from the shallow coral reefs of Straits of Malacca. The new species Stichopus
fusiformiossa has unusual fusiform spicules in the tentacles, which are not found in the other species of the genus. Pseudo-tables and large perforated plates are newly recorded for Stichopus
hermanni Semper, 1868 and Stichopus
vastus Sluiter, 1887, respectively. 相似文献
230.
Dan A. Exton Terry J. McGenity Michael Steinke David J. Smith David J. Suggett 《Global Change Biology》2015,21(4):1383-1394
Biogenic volatile organic compounds (BVOCs), in particular dimethyl sulphide (DMS) and isoprene, have fundamental ecological, physiological and climatic roles. Our current understanding of these roles is almost exclusively established from terrestrial or oceanic environments but signifies a potentially major, but largely unknown, role for BVOCs in tropical coastal marine ecosystems. The tropical coast is a transition zone between the land and ocean, characterized by highly productive and biodiverse coral reefs, seagrass beds and mangroves, which house primary producers that are amongst the greatest emitters of BVOCs on the planet. Here, we synthesize our existing understanding of BVOC emissions to produce a novel conceptual framework of the tropical marine coast as a continuum from DMS‐dominated reef producers to isoprene‐dominated mangroves. We use existing and previously unpublished data to consider how current environmental conditions shape BVOC production across the tropical coastal continuum, and in turn how BVOCs can regulate environmental stress tolerance or species interactions via infochemical networks. We use this as a framework to discuss how existing predictions of future tropical coastal BVOC emissions, and the roles they play, are effectively restricted to present day ‘baseline’ trends of BVOC production across species and environmental conditions; as such, there remains a critical need to focus research efforts on BVOC responses to rapidly accelerating anthropogenic impacts at local and regional scales. We highlight the complete lack of current knowledge required to understand the future ecological functioning of these important systems, and to predict whether feedback mechanisms are likely to regulate or exacerbate current climate change scenarios through environmentally and ecologically mediated changes to BVOC budgets at the ecosystem level. 相似文献