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1.
海州湾人工鱼礁海域鱼类和大型无脊椎动物群落组成及结构特征 总被引：1，自引：0，他引：1
为了解人工鱼礁区鱼类和大型无脊椎动物的数量变动及群落扰动情况,于2003、2004、2005和2007年采用底拖网对人工鱼礁区及邻近对照区进行了调查。结果表明:海州湾人工鱼礁区调查共鉴定鱼类和大型无脊椎动物96种,其中鱼类和节肢类是人工鱼礁区游泳生物的主要种类,分别占55.21%和35.42%,而软体类与棘皮类则分别占7.29%和2.08%。鱼礁区的生物种类数、生物量、丰富度和多样性指数除了呈现明显的季节变化外,年平均生物种类数、生物量、丰富度和多样性均高于对照区,鱼礁增殖效果明显。此外,通过ABC曲线分析发现:除投礁后第4年的鱼礁区春季和秋季外,投礁前和投礁后第1年、第2年的鱼礁区以及对照区各季节的鱼类和大型无脊椎动物群落结构都处于一个扰动状态。 相似文献
2.
近海中上层柔性浮鱼礁设计与应用 总被引：1，自引：0，他引：1
当前我国海洋牧场建设、栖息地改造主要通过底层鱼礁进行,从产生营养物质上升流、饵料场和产卵场及生物链的角度未充分利用整个水体空间,导致效能不能发挥到最佳。为解决这一问题,针对我国东海近海海域海况和生物特性研发了能与底层人工鱼礁协同工作的中上层浮鱼礁。从改善流场、自身体积保持等角度设计了四层网格式柔性浮式鱼礁,进行了浮力、重力及抗浪流能力的校核计算,确定了锚系技术方案及水下效果监控方法。在象山港海洋牧场进行了布放,实际效果测试表明所设计的浮鱼礁可以有效改善区域流场,在最高潮和最低潮时均可保持竖直方向的拉伸状态,最大潮流速度时倾斜角度不超过20度,现场多批次调查及水下视频监控效果显示所研发的鱼礁能够与底层鱼礁协同工作,投放2个月后有鱼类稳定地出现在浮鱼礁周围,取得了良好的效果。 相似文献
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4.
Roberts CM McClean CJ Veron JE Hawkins JP Allen GR McAllister DE Mittermeier CG Schueler FW Spalding M Wells F Vynne C Werner TB 《Science (New York, N.Y.)》2002,295(5558):1280-1284
Coral reefs are the most biologically diverse of shallow water marine ecosystems but are being degraded worldwide by human activities and climate warming. Analyses of the geographic ranges of 3235 species of reef fish, corals, snails, and lobsters revealed that between 7.2% and 53.6% of each taxon have highly restricted ranges, rendering them vulnerable to extinction. Restricted-range species are clustered into centers of endemism, like those described for terrestrial taxa. The 10 richest centers of endemism cover 15.8% of the world's coral reefs (0.012% of the oceans) but include between 44.8 and 54.2% of the restricted-range species. Many occur in regions where reefs are being severely affected by people, potentially leading to numerous extinctions. Threatened centers of endemism are major biodiversity hotspots, and conservation efforts targeted toward them could help avert the loss of tropical reef biodiversity. 相似文献
5.
Coral reefs resemble islands of productive habitats where fishes aggregate, forage, and spawn. Although it has been suggested that some reef fishes use biogenic chemicals as aggregation cues, specific chemicals have not been identified. Dimethylsulfoniopropionate (DMSP), a secondary metabolite of many marine algal species, is released during foraging by higher-order consumers. DMSP has been studied intensively for its role in oceanic sulfur cycles and global climate regulation, but its ecological importance to marine fishes is unknown. We present evidence that planktivorous reef fishes will aggregate to experimental deployments of DMSP over coral reef habitats in the wild. 相似文献
6.
【目的】探索珠海外伶仃人工鱼礁海域鱼类资源增殖效果及礁区生境动态变化,为人工鱼礁的合理建设和规划提供科学依据。【方法】分别于2006年8月及2009年8月、2016年5月,采用拖网调查方式对珠海外伶仃人工鱼礁区附近海域进行本底和跟踪调查,分析游泳生物种类组成、鱼类资源密度和丰度变化,确定优势种和群落特征指数,并通过礁区和对比区生态能质变动趋势分析礁区生态效应和结构稳定性。【结果】调查共采集游泳生物71种,经鉴定隶属于8目34科46属,其中鱼类36种,占50.70%;甲壳类32种,占45.07%;软体类3种,占4.23%。礁区鱼类占比从39.13%提高到63.89%。珠海外伶仃人工鱼礁区附近海域鱼类资源密度和丰度在投礁后明显增加,礁体的投放吸引了中下层鱼类聚集。根据优势种分析结果可知,中下层鱼类为人工鱼礁区附近海域主要优势类群。短吻鲾和二长棘鲷等鱼类成为礁区及其临近海域的绝对优势种类,本底调查中的优势种如黄斑蓝子鱼等大鳞舌鳎等优势度降低。群落特征指数T检验结果表明,礁区与对比区丰富度指数为极显著差异（P<0.01）;礁区生态能质值显著高于对比区（P<0.05）。【结论】人工鱼礁区建设对有效影响范围内鱼类资源恢复具有明显促进作用,以人工鱼礁为基础、资源修复为关键的海洋牧场建设,是未来发展的趋势和重点方向。 相似文献
7.
南海重要珊瑚礁过渡性水域软骨鱼类的组成与分布 总被引：4，自引：0，他引：4
2004年5—7月和2005年3—4月采用深水三重刺网在南海的羚羊礁、华光礁、银砾滩、东岛、滨湄滩、排洪滩、本固暗沙、比微暗沙、武勇暗沙、海鸠暗沙、双子群礁、中业群礁、鲎藤礁、美济礁、仁爱礁、仙宾礁、南方浅滩、棕滩、大渊滩、永署礁、南薰礁、牛轭礁、道明群礁等23座重要珊瑚礁过渡性水域进行了2个航次专业调查，其中有21座岛礁共渔获到7目15科33种408尾软骨鱼类，而美济礁和南方浅滩没有渔获到软骨鱼类。根据调查资料，通过物种各分类阶元的分布、优势度（IRI）和单位努力量渔获量等几个方面分析南海重要珊瑚礁过渡性水域软骨鱼类的组成与分布，旨在为南海珊瑚礁渔业资源的开发和管理提供科学依据。结果表明，西沙群岛的重量单位努力量渔获量范围为73～499kg／10^4m^2，其优势种类是迈氏条尾虹、灰六鳃鲨和黑梢真鲨；中沙群岛的重量单位努力量渔获量范围为114～245kg／10^4m^2，其优势种类是迈氏条尾虹、灰三齿鲨；南沙群岛除了美济礁和南方浅滩外其重量单位努力量渔获量范围为51～846kg／10^4m^2，其优势种类是黑梢真鲨、灰三齿鲨。 相似文献
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2004年5—7月和2005年3—4月采用深水三重刺网在南海的羚羊礁、华光礁、银砾滩、东岛、滨湄滩、排洪滩、本固暗沙、比微暗沙、武勇暗沙、海鸠暗沙、双子群礁、中业群礁、鲎藤礁、美济礁、仁爱礁、仙宾礁、南方浅滩、棕滩、大渊滩、永署礁、南薰礁、牛轭礁、道明群礁等23座重要珊瑚礁过渡性水域进行了2个航次专业调查，其中有21座岛礁共渔获到7目15科33种408尾软骨鱼类，而美济礁和南方浅滩没有渔获到软骨鱼类。根据调查资料，通过物种各分类阶元的分布、优势度（IRI）和单位努力量渔获量等几个方面分析南海重要珊瑚礁过渡性水域软骨鱼类的组成与分布，旨在为南海珊瑚礁渔业资源的开发和管理提供科学依据。结果表明，西沙群岛的重量单位努力量渔获量范围为73～499kg／10^4m^2，其优势种类是迈氏条尾虹、灰六鳃鲨和黑梢真鲨；中沙群岛的重量单位努力量渔获量范围为114～245kg／10^4m^2，其优势种类是迈氏条尾虹、灰三齿鲨；南沙群岛除了美济礁和南方浅滩外其重量单位努力量渔获量范围为51～846kg／10^4m^2，其优势种类是黑梢真鲨、灰三齿鲨。 相似文献
9.
Climate change,human impacts,and the resilience of coral reefs 总被引：11，自引：0，他引：11
Hughes TP Baird AH Bellwood DR Card M Connolly SR Folke C Grosberg R Hoegh-Guldberg O Jackson JB Kleypas J Lough JM Marshall P Nyström M Palumbi SR Pandolfi JM Rosen B Roughgarden J 《Science (New York, N.Y.)》2003,301(5635):929-933
The diversity, frequency, and scale of human impacts on coral reefs are increasing to the extent that reefs are threatened globally. Projected increases in carbon dioxide and temperature over the next 50 years exceed the conditions under which coral reefs have flourished over the past half-million years. However, reefs will change rather than disappear entirely, with some species already showing far greater tolerance to climate change and coral bleaching than others. International integration of management strategies that support reef resilience need to be vigorously implemented, and complemented by strong policy decisions to reduce the rate of global warming. 相似文献
10.
为了对惠东人工鱼礁的投放进行评估以及观察对渔业资源的生物聚集效果,分别于2008年5月和2011年6月对惠东大星山人工鱼礁区进行了拖网和刺网的本底调查和跟踪调查。采用生物资源密度指数(D)、Margalef种类丰度指数(R)、Shannon-Winener多样性指数(H')、Pileou均匀度指数(J')来研究水域生物种群的多样性和资源密度。拖网调查结果表明,投礁后礁区游泳生物种类数、总资源密度、种类丰度指数、多样性指数均有明显的增加,分别为投礁前的1.321倍、2.070倍、1.012倍、1.084倍。刺网调查结果表明,投礁后礁区游泳生物种类数、总资源密度、种类丰度指数、多样性指数,分别为投礁前的2.571倍、7.976倍、2.399倍、2.667倍。投礁后礁区鱼蟹类成为主要的优势类群。这表明鱼礁投放后,对鱼类等的诱集效果显著,群落结构明显优化,礁区水域环境,明显改善。惠东大星山礁区的人工鱼礁增殖体系已基本形成。 相似文献
11.
The blacksmith (Chromis punctipinnis), an abundant pomacentrid fish off southern California, regularly forages on zooplankton during the day and shelters in rocky reefs at night. This behavioral pattern results in the importation of 8 grams of carbon per square meter per year, deposited as feces in the nocturnal shelter. Since blacksmiths regularly return to the same shelters, this represents a transport of extrinsic organic carbon to the reef which is predictable in time and space. 相似文献
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The relationship between natural variations in coral species diversity, reef development, and ecosystem function on coral reefs is poorly understood. Recent coral diversity varies 10-fold among geographic regions, but rates of reef growth are broadly similar, suggesting that diversity is unimportant for reef development. Differences in diversity may reflect regional differences in long-term biotic history in addition to environmental conditions. Using a combination of new and published fossil and stratigraphic data, we compared changes in coral diversity and reef development within the tropical western Atlantic over the past 28 million years. Reef development was unrelated to coral diversity, and the largest reef tracts formed after extinction had reduced diversity by 50%. High diversity is thus not essential for the growth and persistence of coral reefs. 相似文献
13.
【目的】健全的农业保险体系对规避或分散农业经营风险、推动农业现代化发展起着重要作用,
探究农业保险与农业现代化之间的耦合协调以及灰色关联性,对加快实现农业高质量发展至关重要。【方法】
基于 2010—2019 年山东省农业保险与农业现代化的相关数据,运用耦合协调度模型,揭示两大体系之间的耦合
互动关系,并采用灰色关联法分析农业保险对农业现代化发展的影响。【结果】山东省农业保险和农业现代化
的综合发展指数均呈上升态势;农业保险与农业现代化的耦合协调程度由严重失调逐渐趋好到优质协调状态,
耦合度由 2010 年的 0.329 上升至 2019 年的 0.875,改善明显;农业保险体系各指标与农业现代化总体指标的灰
色关联度较高,均在 0.7 以上,其中农险保费收入在财产险保费收入的占比、农险保费收入深度以及农险保费收
入与农业现代化的关联性较高,是主要的影响因素。【结论】提出完善市场化的农业保险机制和提升服务管理
水平、加大农业保险宣传力度和扩大农险覆盖面、推动农业保险与农业现代化融合协调发展等对策建议。 相似文献
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Coral reefs are considered to be a source of atmospheric carbon dioxide because of their high calcium carbonate production and low net primary production. This was tested by direct measurement of diurnal changes in the partial pressure of carbon dioxide (Pco(co2)) in reef waters during two 3-day periods, one in March 1993 and one in March 1994, on Shiraho reef of the Ryukyu Islands, Japan. Although the Pco(co2) values in reef waters exhibited large diurnal changes ranging from 160 to 520 microatmospheres, they indicate that the reef flat area is a net sink for atmospheric carbon dioxide. This suggests that the net organic production rate of the reef community exceeded its calcium carbonate production rate during the observation periods. 相似文献
15.
采用文献查阅、海域实地调查相结合的方法,总结国内外海洋牧场的发展与现状,分析广东人工鱼礁、增殖放流和国家级海洋牧场示范区的建设历程,海洋牧场相关产业的发展现状和存在问题。广东建有50座生态型人工鱼礁区、3个大型人工鱼礁示范区、1个地方人工鱼礁区和15个国家级海洋牧场示范区,合计海域面积1 499.68 km2,建造投放礁体200.4万空m3。目前广东海洋牧场存在管理机制不完善、发展理念和认识不统一、用海海域权责不清、建设技术标准和规范缺乏、科技化程度低、产业化开发受限等问题。基于此,提出广东海洋牧场发展的对策：坚持生态优先,加强多部门统筹协作;创建有利于市场化运作的管理模式;突破海域权属问题;建立广东海洋牧场建设技术标准体系;加强广东海洋牧场建设的基础和关键共性技术研究;因地制宜建立广东海洋牧场产业化模式。了解广东海洋牧场的发展现状,借鉴国内外相关经验探究海洋牧场产业的发展对策,可为广东海洋牧场有效管理、高效可持续开发,以及实现广东海洋牧场三产融合发展提供参考。 相似文献
16.
LT Toth RB Aronson SV Vollmer JW Hobbs DH Urrego H Cheng IC Enochs DJ Combosch R van Woesik IG Macintyre 《Science (New York, N.Y.)》2012,337(6090):81-84
Cores of coral reef frameworks along an upwelling gradient in Panamá show that reef ecosystems in the tropical eastern Pacific collapsed for 2500 years, representing as much as 40% of their history, beginning about 4000 years ago. The principal cause of this millennial-scale hiatus in reef growth was increased variability of the El Ni?o-Southern Oscillation (ENSO) and its coupling with the Intertropical Convergence Zone. The hiatus was a Pacific-wide phenomenon with an underlying climatology similar to probable scenarios for the next century. Global climate change is probably driving eastern Pacific reefs toward another regional collapse. 相似文献
17.
Brachiopods and coralline sponges are the dominant taxa of a series of parallel pantropical communities found in cryptic habitats of Recent coral reefs, where these organisms may cover almost the entire available surface area. It is suggested that the continued survival and success of these and other groups of considerable paleontological importance resulted from their occupation of cryptic reef habitats after competition with more rapidly growing hermatypic corals in the Middle Jurassic when scleractinian reefs first appeared. 相似文献
18.
The scale of larval dispersal of marine organisms is important for the design of networks of marine protected areas. We examined the fate of coral reef fish larvae produced at a small island reserve, using a mass-marking method based on maternal transmission of stable isotopes to offspring. Approximately 60% of settled juveniles were spawned at the island, for species with both short (<2 weeks) and long (>1 month) pelagic larval durations. If natal homing of larvae is a common life-history strategy, the appropriate spatial scales for the management and conservation of coral reefs are likely to be much smaller than previously assumed. 相似文献
19.
Scoffin TP 《Science (New York, N.Y.)》1972,178(4067):1280-1282
Living corals on Bermuda patch reefs build a primary framework which, in places, is so destroyed by boring organisms that the reef surface subsides. Organisms that encrust the reef cavities are preferentially preserved as the framework is bored. Burial by loose sediment stops framework growth, encrustation, and boring. Finally, cementation completes fossilization. 相似文献
20.
Coral reefs under rapid climate change and ocean acidification 总被引：13，自引：0，他引：13
Hoegh-Guldberg O Mumby PJ Hooten AJ Steneck RS Greenfield P Gomez E Harvell CD Sale PF Edwards AJ Caldeira K Knowlton N Eakin CM Iglesias-Prieto R Muthiga N Bradbury RH Dubi A Hatziolos ME 《Science (New York, N.Y.)》2007,318(5857):1737-1742
Atmospheric carbon dioxide concentration is expected to exceed 500 parts per million and global temperatures to rise by at least 2 degrees C by 2050 to 2100, values that significantly exceed those of at least the past 420,000 years during which most extant marine organisms evolved. Under conditions expected in the 21st century, global warming and ocean acidification will compromise carbonate accretion, with corals becoming increasingly rare on reef systems. The result will be less diverse reef communities and carbonate reef structures that fail to be maintained. Climate change also exacerbates local stresses from declining water quality and overexploitation of key species, driving reefs increasingly toward the tipping point for functional collapse. This review presents future scenarios for coral reefs that predict increasingly serious consequences for reef-associated fisheries, tourism, coastal protection, and people. As the International Year of the Reef 2008 begins, scaled-up management intervention and decisive action on global emissions are required if the loss of coral-dominated ecosystems is to be avoided. 相似文献