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Prioritizing localized management actions for seagrass conservation and restoration using a species distribution model 
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下载免费PDF全文 Matthew P. Adams Megan I. Saunders Paul S. Maxwell Daniel Tuazon Chris M. Roelfsema David P. Callaghan Javier Leon Alistair R. Grinham Katherine R. O'Brien 《水产资源保护:海洋与淡水生态系统》2016,26(4):639-659
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Lina M Nordlund Richard K F Unsworth Martin Gullström Leanne C Cullen‐Unsworth 《Fish and Fisheries》2018,19(3):399-412
Seagrass meadows support fisheries through provision of nursery areas and trophic subsidies to adjacent habitats. As shallow coastal habitats, they also provide key fishing grounds; however, the nature and extent of such exploitation are poorly understood. These productive meadows are being degraded globally at rapid rates. For degradation to cease, there needs to be better appreciation for the value of these habitats in supporting global fisheries. Here, we provide the first global scale study demonstrating the extent, importance and nature of fisheries exploitation of seagrass meadows. Due to a paucity of available data, the study used a global expert survey to demonstrate the widespread significance of seagrass‐based fishing activity. Our study finds that seagrass‐based fisheries are globally important and present virtually wherever seagrass exists, supporting subsistence, commercial and recreational activity. A wide range of fishing methods and gear is used reflecting the spatial distribution patterns of seagrass meadows, and their depth ranges from intertidal (accessible by foot) to relatively deep water (where commercial trawls can operate). Seagrass meadows are multispecies fishing grounds targeted by fishers for any fish or invertebrate species that can be eaten, sold or used as bait. In the coastal communities of developing countries, the importance of the nearshore seagrass fishery for livelihoods and well‐being is irrefutable. In developed countries, the seagrass fishery is often recreational and/or more target species specific. Regardless of location, this study is the first to highlight collectively the indiscriminate nature and global scale of seagrass fisheries and the diversity of exploitative methods employed to extract seagrass‐associated resources. Evidence presented emphasizes the need for targeted management to support continued viability of seagrass meadows as a global ecosystem service provider. 相似文献
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海草是一类生活在热带至温带浅海、完全适应海洋环境的沉水被子植物的总称。海草床作为连接珊瑚礁与红树林的纽带，具有重要的生态功能与经济价值。近年来，随着人们对海草认识的不断加深，海草的有性繁殖行为逐渐受到关注，而成花诱导是海草从营养生长向生殖生长过渡的重要环节。本文综述了海草有性繁殖中成花诱因的研究进展，探讨了温度、光照、盐度等相关因子对海草成花诱导的影响，分析了海草响应外界环境刺激与内源信号启动开花途径可能集中在光周期途径、春化途径和自发途径上。建议未来海草床保护修复工作应加强对海草有性生殖行为的研究，明确不同海域海草的集中开花和结果时间，对海草床生态系统的修复与保护具有重要意义。 相似文献
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- Seagrasses such as Zostera marina L. play a key role in coastal ecosystems because of the ecological goods and services that they provide, enhancing biodiversity, productivity and carbon sequestration. Despite their ecological relevance, their distribution is, to date, insufficiently documented and it is estimated that only one‐quarter of their global extent is mapped.
- This study aims to develop a new method to accurately detect and map subtidal seagrass meadows, using Irish seagrass populations as a case study. This method consists of four steps: (i) the development of a species distribution model (SDM); (ii) the use of satellite‐derived images to visually appraise the potential presence and extent of seagrass beds; (iii) field surveys to validate the presence or absence of the seagrass; and finally (iv) the construction of an up‐to‐date detailed map of the seagrass distribution for the region under investigation.
- Results indicate that along the Irish coast, and in western regions in particular, the actual distribution of seagrass is considerably greater than is currently reported. Using the proposed method, 16 new regions occupied by seagrass in areas of interest in County Galway (Kilkieran Bay, Bertraghboy Bay, and Chasla Bay) were identified, accounting for a total of 267.92 ha, which increased the previously documented distribution in this area by 44.74%.
- In this study, we demonstrate the potential of this novel method to efficiently identify and map undocumented subtidal seagrass meadows. As seagrass habitats are under threat globally, the development of new mapping strategies is a critical contribution to current international efforts in seagrass monitoring and management.
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An Erratum has been published for this article in Aquatic Conservation: Marine and Freshwater Ecosystems 12(2), 2002 577
- 1. This research extends techniques of predictive mapping from their application in terrestrial environments to marine landscapes by investigating the relationship between seagrass and hydrodynamics in Core Sound, North Carolina, USA.
- 2. An empirically derived logistic multiple regression model and a Boolean logic suitability model were used to produce several predictive map products, including: susceptibility of seagrasses to storms, probability of seagrass cover, and suitability of areas for restoration of seagrasses. A visual comparison between these maps and conventional seagrass polygon maps allows for a discussion of ‘field’ versus ‘object’ mapping, and the ramifications for management based on different cartographic techniques.
- 3. The predictive method used here showed that only a small portion (19%) of the seagrass bed in the study area would be expected to have a high probability of seagrass coverage. The majority of the seagrass habitat in the study area was predicted to have less than 50% probability of seagrass cover. In addition, 16% of the nearly 2000 ha of seagrass within the study area were predicted to be highly susceptible to acute storm events. Moreover, using a conservative set of site selection criteria, only 7% of the study area encompassed by seagrass habitat was predicted to have a high probability of successful restoration if injured.
- 4. This method provides for an inexpensive way to scale‐up from high‐resolution data to a coarser scale that is often required for conservation and management.
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Abstract This study examined habitat use patterns of newly settled spotted seatrout Cynoscion nebulosus (Cuvier) across several Gulf of Mexico estuaries. Intensive sampling using an epibenthic sled was conducted in three Texas bays and among three potential habitat types. A long‐term data set (1982 to 1997) from the National Marine Fisheries Service was also used to examine C. nebulosus habitat use patterns in both marsh and seagrass‐dominated bay systems for broad regional comparisons along the north‐western Gulf of Mexico. Vegetated habitat types such as seagrass and marsh supported the highest densities and use was dependent upon availability of particular vegetated habitat types. In laboratory mesocosm experiments, both wild‐caught and hatchery‐reared C. nebulosus, showed strong selection for structured and vegetated habitat types. These field and laboratory results suggest that seagrass meadows and marshes may be functioning as important habitat for C. nebulosus in Gulf of Mexico, and other habitat types such as oyster reef need further evaluation. 相似文献
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电子鼻技术的研究进展及其在水产品鲜度评价中的应用 总被引：5，自引：0，他引：5
水产品的质量管理是水产加工企业的重要环节。传统上，水产品的鲜度主要是采用感官评价或气相色谱分析的方法进行的。这些方法费时昂贵，而且不便于对产品质量的适时监测。因此，高效、快捷的水产品质量监测技术的研究受到了很大关注。利用电子鼻测水产品的鲜度，被公认是一种快速、可靠、可实现自动检测、而且对水产品无任何伤害的新型技术。本文阐述了电子鼻的工作原理和化学传感器技术的研究进展，并且讨论了电子鼻技术在水产品鲜度评价中的应用和未来发展前景。 相似文献
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《水生生物资源》2000,13(2):65-76
Lagoon fish in New Caledonia are mainly caught by artisanal fisheries and subsistence fishing. Reef fish are the major component of this catch. The present study aimed at estimating these reef fish standing stocks and at finding the main factors influencing the distribution of these fish. Sampling of 904 stations was stratified according to three zones (north, east and west) and three reef types (barrier, intermediate and fringing). Fish communities exhibited strong heterogeneity in their distribution, showing higher biomass (maximum of 447 g·m–2) and total standing stock (43 000 tonnes) in the north zone than in the east and west zones. Similarly, observed patterns were dependent on reef types: higher biomass and total standing stock being observed on barrier reefs than on intermediate or fringing reefs. The total standing stocks, which were about 65 000 t, were mainly composed of herbivorous fish families such as the Acanthuridae and Scaridae. The differences in the patterns of distribution of species, individuals and standing stocks between reef types may be explained by variations in terrestrial influences and reef morphology, whereas differences among zones were most likely due to accessibility of fishing areas and fishing pressure. The latter is almost non-existent in the north zone, which can thus be considered to be almost unexploited commercially. This most likely explains the high proportion, 77 %, of long-lived species in the biomass of this zone. The results might have implications in management of reefs elsewhere in the South Pacific, for which similar data are only scarcely available. 相似文献
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ABSTRACT: To clarify faunal overlap between a seagrass bed and adjacent coral and sand areas, and the number of reef fishes utilizing the seagrass bed as juvenile habitat, visual censuses were conducted at Amitori Bay, Iriomote Island, Japan. The numbers of species and individuals of fishes were significantly higher in the coral area than in the seagrass bed and sand area. Cluster and ordination analyses based on the number of individuals of each species demonstrated that the fish assemblage structure differed among the three habitats in each season, but with some overlaps. Approximately half the seagrass bed fishes occurred in the adjacent coral area (coral–seagrass species). Dominant species of coral–seagrass species utilized the seagrass bed as an important juvenile habitat. Thus, some overlaps in habitat use were present between the seagrass bed and adjacent coral area. Despite such overlaps, however, coral–seagrass species accounted for only approximately 15% of coral reef fishes overall, indicating that most of the latter hardly utilize the seagrass bed directly in the study area. 相似文献
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I. NÄSLUND 《Aquaculture Research》1989,20(4):463-474
Abstract. Effects of four types of habitat improvement structures have been evaluated in Låktabäcken Creek, a steep and infertile brown trout, Salmo trutta L., stream in Northern Sweden. Boulder dams proved to be the most efficient structure, increasing brown trout densities by up to three times and standing crop by up to five times their original values. Log deflectors gave similar effects on standing crop while boulder groupings and boulder deflectors seemed to be inefficient. Older/larger fish were primarily favoured. No increase in growth or enhanced condition has been registered. Obviously, profitable stream positions for older fish were lacking in Läktabäcken Creek. An increase in the amount of cover and an increase in the winter survival might be secondary effects of alterations. 相似文献
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Pedro Noriega-Curtis 《Aquaculture (Amsterdam, Netherlands)》1979,17(4):335-344
Studies of various parameters associated with productivity were conducted in experimental manured ponds with the object of estimating the effects that organic manure produce on fish yield.Photosynthesis—depth profiles showed autoshading by the plankton resulting in compensation depths of approximately 70 cm. Net photosynthetic rates were found to be only slightly higher than those obtained under chemical fertilization. Their variation seemed to be somewhat independent of the total standing crop of plankton but was more directly related to the composition of the plankton.Several fish yield prediction models based on primary productivity were applied to the experimental data. In every case the results show that the actual yields considerably exceeded the predicted yields.This work gives support to the notion that primary productivity is not sufficient to account for the high fish yields attained in a manured system. Thus it is concluded that manuring of fishponds may not only be a practice of fertilization but also a means of promoting the growth of fish through some other alternative pathway. 相似文献
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Matthew S. Kendall John D. Christensen Christopher Caldow Michael Coyne Christopher Jeffrey Mark E. Monaco Wendy Morrison Zandy Hillis‐Starr 《水产资源保护:海洋与淡水生态系统》2004,14(2):113-132
- 1. A necessary component of implementing a successful marine reserve is the quantification of the biological resources that fall under its protection. Without such an initial assessment, the future effects of the reserve on the local habitat and biotic community cannot be quantified and will remain the subject of debate.
- 2. This study provides such a baseline assessment of fish diversity and habitat types within a recently enlarged marine reserve. Buck Island Reef National Monument, US Virgin Islands, was recently enlarged from approximately 4 km2 to over 76 km2. Areas of sand, seagrass, and hard‐bottom under protection were increased from 0.29 km2, 0.47 km2, and 1.96 km2 to 2.70 km2, 2.89 km2, and 18.30 km2 respectively when the Monument was expanded. A 53 km2 area of pelagic/deep‐water habitat with unknown bottom type is now also protected by the Monument.
- 3. Visual counts of fish within 25×4 m2 transects conducted during the day were used to assess fish community structure and habitat utilization patterns. Species richness, diversity, assemblage structure, and fish density were evaluated and compared among sand, seagrass, and hard‐bottom habitats. Hard‐bottom sites had over twice the mean species richness and diversity as sand and seagrass sites, and several times greater mean fish density.
- 4. Quantification of the fish community in pelagic and deep‐water habitats within the reserve is recommended to provide a more comprehensive assessment of the offshore areas of the reserve. Fish numbers, size, and diversity outside the reserve boundaries must also be evaluated to allow quantification of the effects of the marine reserve on the adjacent fish communities.
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Yohei Nakamura Masahiro Horinouchi Mitsuhiko Sano Takuro Shibuno 《Fisheries Science》2009,75(6):1401-1408
Whilst the importance of seagrass beds as nurseries for coral reef fishes has been clearly recognized, the vast majority of
early studies on fish nursery habitats emphasized the close proximity of the latter to coral reefs. To determine the potential
nursery role of isolated seagrass beds, we investigated the degree to which juvenile emperor fishes (Lethrinidae) utilized
seagrass beds in the presence/absence of adjacent coral habitats at Ishigaki Island (southern Japan), such fishes being known
to use seagrass beds as nurseries. Seagrass beds in close proximity to coral habitats (distance between the two habitats of
50–200 m) had greater densities of lethrinid juveniles than those without adjacent coral habitats (2.5–4 km) for 3 different
sites investigated, although a significant difference was obtained only for 1 site. Juveniles of Lethrinus atkinsoni, L. obsoletus, L. harak, and L. nebulosus were observed in seagrass beds with and without adjacent coral habitats, whereas L. ornatus occurred only in the former. Overall, most lethrinid juveniles utilize seagrass beds irrespective of the presence of adjacent
adult coral habitat, suggesting that both types of seagrass beds would contribute to lethrinid adult populations. Therefore,
management efforts for lethrinid populations should be applied not only to contiguous coral-seagrass habitat systems but also
to isolated habitats. 相似文献
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1. The effect of habitat fragmentation was investigated in two adjacent, yet separate, intertidal Zostera marina beds in the Salcombe Estuary, Devon, UK. The seagrass bed on the west bank comprised a continuous meadow of ca. 2.3 ha, whilst the bed on the east bank of the estuary was fragmented into patches of 6–9 m2. 2. Three 10 cm diameter core samples for infaunal macroinvertebrates were taken from three stations within each bed. No significant difference was found in univariate community parameters between beds, or in measured seagrass parameters. However, multivariate analysis revealed a significant difference in community composition, due mainly to small changes in species abundance rather than differences in the species present. 3. The species contributing most to the dissimilarity between the two communities were polychaetes generally associated with unvegetated habitats (e.g. Magelona mirabilis) and found to be more common in the fragmented bed. 4. A significant difference in median grain size and sorting coefficient was recorded between the two beds, and median grain size was found to be the variable best explaining multivariate community patterns. 5. The results of the study provide evidence for the effects of habitat fragmentation on the communities associated with seagrass beds, habitats which are of high conservation importance. As the infaunal community is perhaps intuitively the component least likely to be affected by fragmentation at the scale observed, the significant difference in community composition recorded has consequences for more sensitive and high‐profile parts of the biota (e.g. fish), and thus for the conservation of seagrass habitats and their associated communities. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
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- 1. Maintaining ecological processes that underpin the functioning of marine ecosystems requires planning and management of marine resources at an appropriate spatial scale.
- 2. The Great Barrier Reef World Heritage Area (GBR) is the world's largest World Heritage Area (approximately 348 000 km2) and second largest marine protected area. It is difficult to inform the planning and management of marine ecosystems at that scale because of the high cost associated with collecting data. To address this and to inform the management of coastal (approximately 15 m below mean sea level) habitats at the scale of the GBR, this study determined the presence and distribution of seagrass by generating a Geographic Information System (GIS)‐based habitat suitability model.
- 3. A Bayesian belief network was used to quantify the relationship (dependencies) between seagrass and eight environmental drivers: relative wave exposure, bathymetry, spatial extent of flood plumes, season, substrate, region, tidal range and sea surface temperature. The analysis showed at the scale of the entire coastal GBR that the main drivers of seagrass presence were tidal range and relative wave exposure. Outputs of the model include probabilistic GIS‐surfaces of seagrass habitat suitability in two seasons and at a planning unit of cell size 2 km×2 km.
- 4. The habitat suitability maps developed in this study extend along the entire GBR coast, and can inform the management of coastal seagrasses at an ecosystem scale. The predictive modelling approach addresses the problems associated with delineating habitats at the scale appropriate for the management of ecosystems and the cost of collecting field data. Copyright © 2010 John Wiley & Sons, Ltd.