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- 1. Forest restoration through silviculture (gardening) programs revives productivity, biodiversity, and stability. As in silviculture approaches, the coral ‘gardening’ strategy is based on a two‐step protocol.
- 2. The first step deals with the establishment of in situ and/or ex situ coral nurseries in which corals are farmed (originating from two types of source material: asexual [ramets, nubbins], and sexual [planula larvae, spat] recruits).
- 3. The second is the reef rehabilitation step, where maricultured colonies are transplanted into degraded sites.
- 4. We compare here the rationale of forest restoration to coral reef ecosystem restoration by evaluating major key criteria. As in silviculture programs, a sustainable mariculture operation that focuses on the prime structural component of the reef (‘gardening’ with corals) may promote the persistence of threatened coral populations, as well as that of other reef taxa, thus maintaining genetic diversity. In chronically degrading reef sites this may facilitate a halt in biodiversity depletion.
- 5. Within the current theoretical framework of ecosystem restoration, the recovery of biodiversity indices is considered a core element since a rich species diversity provides higher ecosystem resilience to disturbances.
- 6. The gardening measure may also be implemented worldwide, eliminating the need to extract existing colonies for transplantation operations. At degraded reef sites, the coral gardening strategy can assist in managing human and non‐human stakeholders' requirements as is done in forest management.
3.
Maria Montseny Cristina Linares Núria Viladrich Pol Capdevila Stefano Ambroso David Díaz Josep‐Maria Gili Andrea Gori 《水产资源保护:海洋与淡水生态系统》2020,30(5):977-987
- Gorgonians dwelling on the Mediterranean continental shelf are among the most frequent fishing bycatch taxa. These species display several traits, such as long lifespans and slow growth, which make them very vulnerable to the impacts caused by fishing activities with far‐reaching and long‐lasting effects.
- Hence, restoration and mitigation actions are crucial to enhance and speed up the natural recovery of damaged cold‐water coral gardens. Given the growing concern to develop effective and affordable restoration actions, the present study aims to propose and technically validate a new large‐scale and cost‐effective restoration method.
- This technique, named ‘badminton method', consists of attaching bycatch Eunicella cavolini colonies to cobble supports and returning them to the continental shelf by gently throwing the gorgonian transplants directly from a boat.
- Two consecutive field experiments were conducted in order to find the best cobble type support and gorgonian size to be used: first, to evaluate the landing efficiency of gorgonian transplants at different depths (from 5 to 30 m) and second, to evaluate their capability to maintain a correct position over time.
- Natural cobbles with large gorgonians attached were the best option. Field results and modelling approaches suggest that the transplants would correctly land on the continental shelf seabed in a predicted area of around 60 m2. Moreover, they would successfully maintain an upright position ensuring gorgonian survival over time.
- The success of this method highlights the feasibility of large‐scale and low‐cost restoration actions with promising results for the conservation and recovery of cold‐water coral gardens.
4.
Lipid distribution in branching coral Montipora digitata 总被引:1,自引:0,他引:1
Hirosuke OKU Hideyuki YAMASHIRO Kyoko ONAGA Hironori IWASAKI Kensaku TAKARA 《Fisheries Science》2002,68(3):517-522
>ABSTRACT: The lipid profile was studied along the branch length, from the top, middle to base portion, of coral Montipora digitata to gain more insight into the physiological significance of lipids in the coral energy budget. The lipids of M. digitata consisted of seven major lipid classes: polar lipid, sterol, free fatty acid, unknown lipids 1 and 2, triacylglycerol (TG), and wax ester. The concentration of storage lipids, TG, and wax ester showed a top–base gradient along the length, whereas the levels of free fatty acid and unknown lipids showed a base–top gradient. The proportions of polar lipid and sterol in the top portion of the branch were slightly higher than those in the base portion. This observation appeared to be compatible with the view that the increased energy expenditure for proliferation enhanced the mobilization of the storage fuel lipids of wax ester and TG rather than the structure lipids of polar lipids and sterols at the top portion of the branch. Compositions of fatty acid also showed a length-wise diversity. The top portion had a lower proportion of palmitic acid (16 : 0) in all lipid classes of fatty acid ester, suggesting that this fatty acid was preferentially mobilized at the top portion, probably for the growth of coral cells. 相似文献
5.
Andrew W. Bruckner 《Aquarium Sciences and Conservation》2001,3(1-3):79-94
The extraction of coral reef organisms for the aquarium and curio trade is reported to be contributing to coral reef degradation. The total international trade and associated impacts are unknown, because data are collected only for organisms listed on Appendix II of CITES, which include stony corals, antipatharians and giant clams. CITES data indicate that trade in live stony coral and reef substrate (live rock) increased by 15–30% each year during the 1990s, with most exports since 1992 from Indonesia and Fiji. Overall, 19% of all stony coral traded (by item) from 1985 to 1997 was live; 71kern-1pt% of this was traded between 1993 and 1997 (52% of total trade). Although tracking trade using information from the CITES Trade Database provides limited information (e.g., coral is reported to genus, and volume is reported by item or weight), the CITES mechanism promotes the development of strategies to protect resources. In response to CITES requirements, Indonesia developed a management plan for sustainable harvest of corals, but not for non-CITES listed species such as soft corals and fishes. Trade in hard and soft coral provides revenue for developing countries; however, in order to be of lasting value the industry must be developed with a conservation ethic. This requires support for international programs such as CITES, management plans for sustainable harvest, and improved enforcement. 相似文献
6.
J. Charles Delbeek 《Aquarium Sciences and Conservation》2001,3(1-3):171-181
There Have Been Significant Technical Advances in Marine Aquarium Maintenance in The Last 20 Years. It is Now Possible to Maintain, Grow and Reproduce in Aquaria Many of the Coral Species Found on Coral Reefs. Due to the increased Demand For Live Corals and Other Reef Invertebrates, The Commercial Production of these Organisms for the Home Aquarium Market Has Become Feasible. This Paper Describes the Early Beginnings of Live Coral Propagation, Current Coral Propagation Facilities Located in Europe, North America, and the Pacific Basin Followed by a Discussion of an Example of the Possible Future for Coral Farming, Namely Propagation by Sexual Reproduction. Suggestions for Areas of Further Research in Captive Coral Propagation are Also Presented. 相似文献
7.
南海主要珊瑚礁(鱼旨)科鱼类的组成与分布 总被引:2,自引:0,他引:2
1998年3~5月和1999年5~6月,采用手钓、延绳钓和刺网3种作业方式在西沙的浪花礁、华光礁、琛航岛、永兴岛、北礁和南沙的渚碧礁、南薰礁、东门礁、美济礁、赤瓜礁、永署礁、华阳礁等12座珊瑚礁水域进行了2个航次的鱼类资源调查,捕获科鱼类6属25种,渔获量计942尾256.4kg;其中在南沙调查区捕获6属22种,共641尾205.5kg,优势种依次为尾纹九棘鲈、蜂巢石斑鱼、六角石斑鱼、黑边石斑鱼;在西沙调查区捕获6属14种,共301尾50.9kg,优势种依次为尾纹九棘鲈、六角石斑鱼、黑边石斑鱼、蜂巢石斑鱼,同时分析了主要种类尾纹九棘鲈、六角石斑鱼和蜂巢石斑鱼的生物学特征。 相似文献
8.
Lipid contents and compositions of the bleached Okinawan corals were analyzed for the first time. Bleached corals collected
at Sesoko Okinawa, Japan (26°38′N, 127°52′E), after the 1998 bleaching event showed decreased lipid content with a concomitant
decline of wax in the lipid composition. The reductionin the lipid content of corals showed diversity depending on their colony
morphology. On the whole, corals of massive morphology were relatively rich in lipid even after the bleaching event, and hence
lesser reduction in the lipid content compared with the cases for those of branching morphology. Furthermore, there was a
positive correlation between lipid content and zooxanthellae density in the bleached corals, suggesting again the importance
of symbiont for the supply of lipid to the host cells, and hence for the survival of the bleaching event. 相似文献
9.
Evaluation of coral bleaching condition <Emphasis Type="Italic">in situ</Emphasis> using an underwater pulse amplitude modulated fluorometer 总被引:3,自引:0,他引:3
Mineo?OkamotoEmail author Satoshi?Nojima Yasuo?Furushima Hajime?Nojima 《Fisheries Science》2005,71(4):847-854
ABSTRACT: Photosynthetic activities of hermatypic corals (28 genera, c . 68 species and c. 92 specimen) were measured in November 2000 at Sekisei lagoon, Okinawa, Japan, using an underwater pulse amplitude modulated fluorometer. Maximum quantum yield (Fv/Fm) ranged from 0.61 to 0.70 and had an average value of 0.664 (standard deviation [SD], 0.0289). Following the measurement of Fv/Fm, quantum yield (Fm'-F)/Fm' at eight-leveled actinic-light intensities were obtained from all specimens. Values of electronic transport rates (ETR) were nearly the same under low photosynthetic active radiation (PAR; µmol quanta/m2 per s) condition and varied with increasing PAR. The value of ETR at 100 µmol quanta/m2 per s ranged from 21.3 to 30.0 and had an average of 27.8 (SD, 2.09). In August 2001, a coral bleaching event was observed in Sekisei Lagoon. During the event, photosynthetic activities of 21 specimens of eight species (seven genera) were measured. By applying two indicators, Fv/Fm and ETR at 100 µmol quanta/m2 per s obtained in August 2000, 18 of 21 specimens were suggested under the bleaching process. In case of Porites lutea , seven colonies were visually evaluated for their condition of bleaching and were found to have two 'normal', three 'slightly bleached' and two 'heavily bleached'. From the density of zooxanthellae, colonies evaluated 'normal' or 'slightly bleached' did not show an apparent difference. However, they were clearly identified by Fm/Fv and ETR at 100 µmol quanta/m2 per s. 相似文献
10.
南沙群岛重要珊瑚礁水域鱼类资源数量分布 总被引:6,自引:3,他引:6
1998年3—5月和1999年5—6月.采用手钓、延绳钓和流刺网3种作业方式在南沙群岛的渚碧、南薰、东门、美济、赤瓜、永署和华阳等7座珊瑚礁水域进行了2个航次的鱼类资源调查。结果表明,7座珊瑚礁水域不同作业方式的鱼类资源相对丰盛度差别较大,其中刺网以永暑礁最高,手钓以华阳礁最高,延绳钓以南薰礁最高;同时.刺网和手钓不同水深区域鱼类资源的相对丰盛度也不相同.其中刺网以11~30m区域最高.手钓以10m以浅和51~80m区域较高;分析认为,造成礁区之间鱼类相对丰盛度差异的主要原因不是初级生产力.而是生态环境因素,主要是礁盘形态和大型海藻的数量。另外.各礁区水域的优势类群有明显不同.这主要与洞穴的大小和数量、大型海藻及珊瑚的种类和数量等生物和非生物环境有关。 相似文献