班公湖-怒江缝合带中段构造演化再探讨

对于班公湖-怒江缝合带中段的拼合时间,根据藏北地区中部侏罗纪生物礁发育的层位和其变化规律及含礁地层与下伏地层的接触关系,认为该缝合带中段拼合于中侏罗世末期或晚侏罗世初期(沙木罗组沉积期之前),生物礁的生长代表了班公湖-怒江缝合带拼合后的残留盆地浅海相沉积。研究表明班公湖-怒江缝合带中段在演化过程中经历了洋盆裂谷阶段(～P1)、初始洋盆和成熟大洋阶段(T～J2)、洋内俯冲(J2～J3)、残余洋盆阶段(J2～J3)、洋盆消亡闭合阶段(J3～K1)。     

江门三号人工鱼礁集鱼效果初步评价

为了解江门三号人工鱼礁的投放对游泳生物的诱集效果,分别于2003年1月和2008年9月对江门三号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＇)来研究水域生物的资源密度和种群多...     

海南岛东、南部珊瑚礁生态健康状况初步分析

为评价海南岛东、南部珊瑚礁生态健康状况,2004年8月对陵水的分界洲岛,三亚的鹿回头湾、榆林湾、蜈支洲岛,琼海的潭门港、龙湾港,文昌的铜鼓岭和长圮港等区域沿岸珊瑚礁进行监测,采用LineIntercept Transect断面法进行调查。通过对造礁石珊瑚种类、覆盖度、死亡率、补充量和发病率等指标分析海南岛东、南部近岸造礁石珊瑚的生态特点。结果表明:海南岛东、南部近岸珊瑚礁发育良好,种类丰富,生物多样性较高。共发现造礁石珊瑚13科32属77种。由于海洋捕捞和海水养殖等人类开发强度加大,该地区近岸部分区域的珊瑚礁生态环境呈退化趋势,珊瑚健康状况受到严重影响。长圮港、潭门港及铜鼓岭珊瑚健康状况较差;三亚鹿回头等区域局部珊瑚生态健康状况良好,生长呈恢复趋势;远离海岸的岛屿区域,如蜈支洲岛和分界洲岛,由于来自陆地的污染和影响小,珊瑚健康状况呈现良好。     

方形人工鱼礁通透性及其对礁体周围流场影响的数值实验

基于考虑不同形状大小、组合规模的人工鱼礁投放于不同水域环境后形成的流态变化有较大差异,设计x、y、z三个方向不同通透方式的单个正方体人工鱼礁,采用LES(大涡模拟)紊流模式,对定常来流速度下人工鱼礁单体附近流场进行三维数值模拟,建立反映礁体结构的通透系数与礁体产生流场变化的关系。结果显示:上升流和背涡流的规模随通透系数增加而减小;来流方向上,礁体迎流面、背流面的通透系数变化对上升流和背涡流规模影响较为显著,而内部结构的变化则作用不明显,礁体上方与侧方的开口对上升流和背涡流的影响也不显著。迎流面通透系数变化是背涡流规模影响的主要因素。方形单礁缓流区体积随通透系数Tin增大呈线性减小,关系为V_x=-1241.8T_in+1206。通过该研究可在数值计算中通过通透系数与流场变化的关系,实现将复杂礁体简单化,有效地提高计算效率;为将小范围模拟扩大到群礁、甚至大海域的模拟,定量评估人工鱼礁的生态效应打下基础。     

Ridge to reef modelling for use within land–sea planning under data‐limited conditions

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Phosphorus Fertility Assessment of Intensively Farmed Areas of Catchments Draining to the Great Barrier Reef World Heritage Area; 1: Soil Phosphorus Status

Abstract

Australia's reef water quality protection plan has a key objective: “reduce the load of pollutants from diffuse sources in the water entering the Reef.” This article reports on a survey to assess the contemporary phosphorus (P) status of fertilized cropping soils across 21 catchments in coastal Queensland, Australia. The survey focused on surface soils from cane farms, vegetable and subtropical/tropical fruit tree sites. There were sampling depth effects on P levels in sugar and fruit tree sites (lower with depth). Importantly, 84% of 105 sugarcane sites were excessively fertile and only 3% rated low (P deficient). Some 75% of 16 vegetable sites and 38% of 8 fruit tree sites had excess ratings for extractable soil P fertility. Highest total P levels (0–10 cm) occurred in fruit tree sites, followed by vegetable and sugarcane soils. There are regional differences in P soil fertility, and the recycling of mill by‐products needs attention. Part 2 (Bloesch and Rayment 2006 Bloesch, P. M. and Rayment, G. E. 2006. “Phosphorus fertility assessment of intensively farmed areas of catchments draining to the Great Barrier Reef World Heritage Area, 2: Potential of soils to release soluble phosphorus”. In Communications in Soil Science and Plant Analysis 37 [Google Scholar]) examines the potential of these soils to release soluble P in a nutrient‐sensitive area.     

珊瑚礁生态系统中造礁石珊瑚退化原因分析与维护技术进展

珊瑚对环境要求较高,温度、盐度、pH、重金属、悬浮泥沙、紫外线等因素都可能造成珊瑚的退化.又因为造礁石珊瑚是现代珊瑚礁的框架,本研究首先基于造礁石珊瑚的生存状况及其与珊瑚礁生态系统的密切关系,分析了其退化原因及可能产生的后果,进而从珊瑚礁生物增殖放流、人工养殖移植技术、相关功能基因研究、科学有效的监测管理等多个角度,综...     

Ex situ Culture of Colonial Marine Ornamental Invertebrates: Concepts for Domestication

The worldwide market for ornamental saltwater invertebrates supplies the needs of millions of aquarium hobbyists, as well as for public exhibition (zoos, aquaria), universities, and research institutions. The large-scale continuous collection of marine organisms is responsible, in many places, for the destruction of habitats, including coral reefs. The perceived expansion of the animal trade further threatens these fragile habitats. In the present paper, several concepts for the domestication of marine ornamental invertebrates (mainly colonial species) are discussed, offering an alternative commercial approach. The major rationale is based on future ex situ propagation, not field collections; a strategy aimed to circumvent the need for wild-harvested animals. This strategy is based on: (1) collection, settlement and metamorphosis of large numbers of larvae from marine organisms or of naturally shed germ cells under aquarium conditions, where survivorship exceeds several orders of magnitude than that in nature; (2) fragmentation of very small pieces (such as the size of a single polyp in colonial corals or blood vessel ampullae in tunicates) for the production of new colonies; (3) the development of replicates and inbred-lines from chosen ornamental species; (4) the use of cryopreservation of larvae and germ cells which will support the supply of material year-round; (5) several concepts for husbandry methods. Some benefits and deficiencies associated with the strategy for ex situ cultures are discussed, revealing its importance to the future of the trade.     

许氏平鲉、大泷六线鱼临界游速与爆发游速及其生理指标的研究

利用垂直循环回流水槽和PVC水槽,分别测定了许氏平鲉Sebastes schlegeli、大泷六线鱼Hexagram-mos otakii的临界游速和爆发游速,并分析了鱼类游泳后对其生理指标的影响。结果表明：体长为10~22cm的许氏平鲉其临界游速为44.69~69.07 cm/s,其相对临界游速为3.11~4.69 BL/s;体长为10~22 cm的大泷六线鱼其临界游速为42.39~82.93 cm/s,其相对临界游速为3.45~4.90 BL/s;体长为10~22 cm的许氏平鲉其爆发游速为76.68~118.18 cm/s;体长为10~22 cm的大泷六线鱼其爆发游速为81.69~121.25 cm/s。根据临界游速测定结果,估算出许氏平鲉和大泷六线鱼的最大游泳距离分别为6 776.4 m和7 423.2 m;根据爆发游速的测定结果估算出两种鱼的最适逃逸距离为15~25 m。临界游泳疲劳后,许氏平鲉血糖、血乳酸和肌肉乳酸含量均显著高于对照组（P〈0.05）,肌糖元、肌肉蛋白与对照组无显著差异（P〉0.05）;大泷六线鱼血乳酸、肌肉乳酸含量显著高于对照组（P〈0.05）,血糖、肌糖元、肌肉蛋白含量显著低于对照组（P〈0.05）。爆发游泳疲劳后,许氏平鲉血糖、血乳酸、肌肉乳酸含量均显著高于对照组（P〈0.05）,肌糖元含量与对照组无显著差异（P〉0.05）;大泷六线鱼血糖、肌糖元、肌肉蛋白含量显著低于对照组（P〈0.05）,血乳酸含量显著高于对照组（P〈0.01）,肌肉乳酸含量显著高于对照组（P〈0.05）。     

模拟海底水流和光照条件下光棘球海胆行为特征及其聚礁效果的初步研究

为观察光棘球海胆Strongylocentrotus nudus在饱食、饥饿和饥饿再投喂状态下的行为特征,及其对水泥、PVC两种材质模型礁的聚集特性,在实验室中模拟光棘球海胆栖息海域底层的昼夜水流速度和光照强度进行试验。结果表明:当光照强度达到560 lx、水流速度达到20 cm/s(9:00)时,均匀分布的光棘球海胆有90%向模型礁附近区域移动;当光照强度和水流速度下降时,光棘球海胆向模型礁附近区域外移动;运动趋势明显的光棘球海胆在饱食、饥饿和饥饿再投喂3种状态下的平均移动速度分别为0.039、0.041、0.052 cm/s,3种状态下光棘球海胆顺、逆水流运动次数的比值依次为饥饿状态(1.63)饱食状态(1.18)饥饿再投喂状态(0.73),饥饿再投喂状态下光棘球海胆的活跃程度高于饱食和饥饿状态;鱼礁材质也影响光棘球海胆的聚集行为,光棘球海胆在饱食、饥饿和饥饿再投喂状态下对水泥模型礁的平均聚集率分别为25%、17%、24%,对PVC模型礁的平均聚集率分别为16%、7%、12%,光棘球海胆对两种模型礁的聚集效果均为饱食状态饥饿再投喂状态饥饿状态。研究表明,光棘球海胆在饱食和饥饿再投喂状态下对两种模型礁的聚集效果较好,而水泥材质的模型礁比PVC材质的模型礁聚集效果更好。