Modelling the timing of plankton production and its effect on recruitment of cod (Gadus morhua)     

Brander  K. M.; Dickson  R. R.; Shepherd  J. G. 《ICES Journal of Marine Science》2001,58(5):962-966

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Population Structure and Secondary Production of the Mediterranean Octocoral Lophogorgia ceratophyta (L. 1758)     

M. Mistri 《Marine Ecology》1995,16(3):181-188

Abstract. The gorgonian Lophogorgia ceratophyta thrives in turbid water at Tinetto Rock, La Spezia Gulf, Ligurian Sea. Its age structure suggests that the population is in a steady state; nevertheless, it is difficult to discern whether the main factors controlling this population are biological or event-related. Secondary production was estimated by means of an increment-summation method and yielded 0.54 g ash-free dry weight (AFDW)*m^-1 a^-1. This estimate does not take into account biomass losses due to reproductive output and non-lethal predation. Standing stock biomass was 5.44 g AFDW e m^-2. The annual P/B ratio was 0.10 and turnover time about 10a  相似文献   

虾池的溶解氧含量及其补充量和消耗量   总被引：8，自引：0，他引：8  

林斌  黄凌风  沈国英 《台湾海峡》1995,14(1):9-14

对对虾养殖池塘溶解氧含量及其收支情况的研究结果表明，虾池DO值具有明显的季节和昼夜变化。浮游植物光合作用是虾池溶解氧补充的主要来源，夏季最高可超过5mg／（dm3·d）。养殖后期对虾的耗氧量占总耗氧量的34％，底质和池水耗氧量分别占30％和35％。根据虾池氧的收支情况讨论了池养对虾的生产容量。  相似文献   

Primary production in the eastern tropical Pacific: A review   总被引：2，自引：12，他引：2  

J. Timothy Pennington  Kevin L. Mahoney  Victor S. Kuwahara  Dorota D. Kolber  Ruth Calienes  Francisco P. Chavez   《Progress in Oceanography》2006,69(2-4):285

The eastern tropical Pacific includes 28 million km² of ocean between 23.5°N and S and Central/South America and 140°W, and contains the eastern and equatorial branches of the north and South Pacific subtropical gyres plus two equatorial and two coastal countercurrents. Spatial patterns of primary production are in general determined by supply of macronutrients (nitrate, phosphate) from below the thermocline. Where the thermocline is shallow and intersects the lighted euphotic zone, biological production is enhanced. In the eastern tropical Pacific thermocline depth is controlled by three interrelated processes: a basin-scale east/west thermocline tilt, a basin-scale thermocline shoaling at the gyre margins, and local wind-driven upwelling. These processes regulate supply of nutrient-rich subsurface waters to the euphotic zone, and on their basis we have divided the eastern tropical Pacific into seven main regions. Primary production and its physical and chemical controls are described for each.Enhanced rates of macronutrient supply maintains levels of primary production in the eastern tropical Pacific above those of the oligotrophic subtropical gyres to the north and south. On the other hand lack of the micronutrient iron limits phytoplankton growth (and nitrogen fixation) over large portions of the open-ocean eastern tropical Pacific, depressing rates of primary production and resulting in the so-called high nitrate-low chlorophyll condition. Very high rates of primary production can occur in those coastal areas where both macronutrients and iron are supplied in abundance to surface waters. In these eutrophic coastal areas large phytoplankton cells dominate; conversely, in the open-ocean small cells are dominant. In a ‘shadow zone’ between the subtropical gyres with limited subsurface ventilation, enough production sinks and decays to produce anoxic and denitrified waters which spread beneath very large parts of the eastern tropical Pacific.Seasonal cycles are weak over much of the open-ocean eastern tropical Pacific, although several eutrophic coastal areas do exhibit substantial seasonality. The ENSO fluctuation, however, is an exceedingly important source of interannual variability in this region. El Niño in general results in a depressed thermocline and thus reduced rates of macronutrient supply and primary production. The multi-decadal PDO is likely also an important source of variability, with the ‘El Viejo’ phase of the PDO resulting in warmer and lower nutrient and productivity conditions similar to El Niño.On average the eastern tropical Pacific is moderately productive and, relative to Pacific and global means, its productivity and area are roughly equivalent. For example, it occupies about 18% of the Pacific Ocean by area and accounts for 22–23% of its productivity. Similarly, it occupies about 9% of the global ocean and accounts for 10% of its productivity. While representative, these average values obscure very substantial spatial and temporal variability that characterizes the dynamics of this tropical ocean.  相似文献   

Ecosystem indicators derived from satellite remotely sensed oceanographic data for the North Pacific     

Polovina  Jeffrey J.; Howell  Evan A. 《ICES Journal of Marine Science》2005,62(3):319-327

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礁膜配子放散条件的研究   总被引：2，自引：0，他引：2  

陈昌生 《台湾海峡》1996,15(2):154-158

本文报道了礁膜配子的放散与温度、光照、比重的关系。结果表明，自然海区的礁膜在白天大量放散配子。配子放散的适宜温度为１９－２１℃；光照为２０００－５０００ｌｘ时能促进配子大量放散出来；配子放散的适宜比重为１．０５－１．０２５；这些研究结果将为礁膜人工育苗提供一些科学依据。  相似文献   

不同水温对文昌鱼性腺发育的影响   总被引：10，自引：1，他引：10  

林加涵  方永强 《台湾海峡》1996,15(2):170-173,T001

研究表明，不同水温对文昌鱼性腺发育分化和成熟有十分显著的影响。１４℃对文昌鱼性腺发育没有显著的作用，２０和２５℃十分有利于性腺发育和成熟，经４０ｄ培养，出现一些雌、雄文昌鱼产卵和释精以及加速性腺发育。本文还讨论了水温促进性腺发育可能的机制。  相似文献   

厦门文昌鱼人工繁育批量生产技术研究   总被引：3，自引：0，他引：3  

周仁杰  方琦 《台湾海峡》2007,26(1):121-128

2005年5月21日至7月6日从厦门市翔安区欧厝附近海域采集文昌鱼亲体6批共计550余尾，移入室内进行强化培育．7月16日和17日夜间，培育的亲体自然排放精卵并受精，共获得受精卵125万粒．受精卵孵化获得浮游幼体115万尾，孵化率达92．0％．孵化的幼体经25d较高密度人工培育，获得99．2万尾体长0．31～0．72cm的文昌鱼苗及未成苗浮游幼体；分苗疏养后，又经28d继续培育，存活的幼体几乎全部潜入沙层中，最终获得体长0．55～1．30cm的厦门文昌鱼潜沙苗23．2万尾，其53d育苗成活率达20．7％．这是国内外首次人工培育获得成批量的文昌鱼增养殖苗种．进而于2005年11月6日向厦门文昌鱼自然保护区实施了国内外首次的文昌鱼资源人工增殖放流．  相似文献   

天目山千亩田泥炭腐殖化度记录的中全新世气候变化   总被引：11，自引：0，他引：11  

尹茜  朱诚  马春梅  王富葆  赵志平  郑朝贵  黄林燕  田晓四 《海洋地质与第四纪地质》2006,26(6):117-122

以14C测年为基础,构建了天目山千亩田地区泥炭沼泽剖面年龄-深度模式曲线,通过该区的腐殖化度与烧失量分析研究,发现两者呈现出很好的相关性,共同记录了该地区4 200 aBP以来的气候变化,可划分出3个主要阶段:早期(4 135±40~3 200 aBP)泥炭腐殖化度偏低,指示气候湿热;中期(3 200~630 aBP)泥炭腐殖化度偏高,指示气候温凉偏干;晚期(630 aBP以来),泥炭腐殖化度偏低,气候温凉湿润。  相似文献   

Interactions between grey seal (Halichoerus grypus), Atlantic salmon (Salmo salar), and harvest controls on the salmon fishery in the Gulf of Bothnia     

Jounela  P.; Suuronen  P.; Millar  R.B.; Koljonen  M-L. 《ICES Journal of Marine Science》2006,63(5):936-945

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