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1.
为了探究盐度和氨氮对方斑东风螺生理代谢的影响,本文采用实验生态学方法,研究了不同盐度和氨氮浓度条件下方斑东风螺(Babylonia areolata)的存活以及能量收支变化。结果显示,方斑东风螺的存活率随着盐度上升呈现先上升后下降的趋势,当盐度为25和30时,方斑东风螺的存活率为100%,低盐96hLC50为10.14,高盐为44.36;方斑东风螺存活率随氨氮浓度上升逐渐下降,当氨氮质量浓度为0~20mg/L时,存活率均为100%;氨氮96hLC50为253.83mg/L。盐度和氨氮对方斑东风螺的摄食率、排粪率、耗氧率和排氨率均具有显著影响(P<0.05)。盐度实验中,方斑东风螺的摄食率、排粪率和排氨率在盐度30时达到最大值,分别为20.50、8.62和0.07mg/(g·h),耗氧率在盐度35时达到最大值,为1.84mg/(g·h)。氨氮实验中,摄食率和排粪率在10mg/L时达到最大值,分别为23.58和10.42mg/(g·h),耗氧率和排氨率在20mg/L时达到最大值,分别为2.49和0.13mg/(g·h)。通过能量收支方程发现,随着盐度和氨氮浓度的上升,方斑东风螺生长能占比均呈现先上升后下降的趋势,其在盐度30和氨氮浓度5mg/L时达到最大值。本研究首次从能量收支角度出发,探讨了盐度和氨氮对方斑东风螺生理代谢的影响,可为其工厂化养殖提供参考。 相似文献
2.
在实验室条件下,设置12、17、22、27和32℃五个温度梯度和12、17、22、27和32五个盐度梯度,研究了不同温度和盐度对大竹蛏(Solen grandis)耗氧排氨的影响。结果表明:随着温度的升高耗氧率先降低再逐渐升高,在温度为22℃时为最小值1.571 mg/(g·h);排氨率先降低后升高再降低,在温度17℃时为最小值0.127 mg/(g·h)。随着盐度增加耗氧率先升高后降低,在盐度22时达到最大值3.106 mg/(g·h),排氨率先降低再升高,在盐度为27时为最小值为0.145 mg/(g·h)。在盐度32时,不同温度的O:N范围是5.525~79.037。在温度12℃时,不同盐度下的O:N范围是4.378~16.755。不同温度下耗氧率Q_(10)变化范围为1.054~2.421,排氨率的Q_(10)变化范围是0.748~1.256。研究结果为进一步完善大竹蛏的人工养殖技术提供参考。 相似文献
3.
在水温为25～31℃、p H 7.70~8.17、溶解氧≥5.0mg/L、自然光照的条件下,作者采用半静水法研究了亚硝酸态氮与非离子氨在不同盐度条件下对花鲈(Lateolabrax maculatus)幼鱼(50.33 g±4.35 g)的急性毒性、半致死量浓度、安全质量浓度及不同盐度条件下氨氮胁迫对花鲈幼鱼耗氧率与排氨率的影响。结果表明,花鲈幼鱼在盐度0、10、20时,亚硝酸盐安全浓度分别为16.357、52.540、58.622 mg/L,总氨氮安全浓度分别为0.794、4.625、5.163 mg/L,非离子氨安全浓度分别为0.584、2.313、1.951 mg/L。实验结果说明,盐度和氨氮联合胁迫对花鲈幼鱼的耗氧率、排氨率有显著影响,盐度10时耗氧率和排氨率最低。 相似文献
4.
采用封闭流水式实验方法,研究了氨氮、温度和体重对大口黑鲈(Micropterussalmoides)耗氧率、窒息点的影响。结果表明:在设定的总氨氮浓度0—8.61mg/L范围,随着氨氮浓度增加,大口黑鲈幼鱼耗氧率呈现先增加后降低的趋势,峰值为0.338mg/(g·h),窒息点随着氨氮浓度的增加而递增,影响显著(P0.05);在13—33°C的实验温度范围,随着温度升高,耗氧率先增加,在29°C时达到峰值0.392mg/(g·h),随后出现下降。在体重6.66—15.87g范围,耗氧率随着体重的增加而下降,最低值为0.112mg/(g·h);耗氧率存在明显的昼夜节律变化,夜均0.214mg/(g·h)日均0.199mg/(g·h),二者差异显著(P0.05),并在2:00—6:00和18:00—20:00时间段出现两个峰值。 相似文献
5.
我国氨氮海水质量基准的探讨 总被引：2，自引：0，他引：2
我国现行的氨氮海水质量标准参照国外基准与标准制定,未考虑是否能够有效保护中国海洋物种,科学性欠缺。对我国海水氨氮质量基准进行研究,采用美国EPA推荐的物种敏感度排序(SSR)技术,结合美国海水氨氮水质基准数学模型,搜集利用我国15种海水水生生物的非离子氨毒性数据,根据非离子氨氮和总氨氮转换公式,得出水体在不同pH值、温度和盐度条件下的总氨氮水质基准在pH为7.0~9.0、温度为0~30℃的范围内,盐度为10时,基准最大浓度(CMC)和基准连续浓度(CCC)的范围分别为0.089~57.141 mg/L与0.007~4.365 mg/L;盐度为20时,CMC和CCC的范围分别为0.092~61.152 mg/L与0.007~4.671 mg/L;盐度为30时,CMC和CCC的范围分别为0.095~65.446 mg/L与0.007~4.999 mg/L;3个环境因子,对CCC和CMC的影响程度由大到小依次为:pH、温度、盐度。相对于美国,我国急性基准的取值区间收缩了5倍,慢性基准的取值区间收缩了10倍。研究结果认为,现行的非离子氨数值应修正为0.007 mg/L才能有效保护我国海洋生物,同时建议使用总氨氮的基准来管理海水中氨氮变化。为修订我国氨氮海水质量标准提供了科学依据。 相似文献
6.
对小荚蛏(Siliqua minima)繁殖、幼虫培育、变态附着及稚贝培育进行了研究。结果表明,小荚蛏繁殖盛期是每年的4月底至5月初,壳长3cm左右的雌性成熟个体最多,产卵可达10万粒左右,卵径约60μm。在盐度20,水温21～22℃,pH7.8的条件下,受精卵经过28h发育至D形幼虫。26℃时胚胎的存活率和孵化率最高,盐度21～36之间胚胎的存活率和孵化率差异不大。温度对幼虫生长发育影响明显,18℃和30℃试验组,幼虫不能存活,22℃组幼虫存活率最高,但生长速度慢于26℃组。盐度对幼虫生长影响明显,盐度为16时,幼虫存活率最高,但生长速度略慢,随着盐度升高,存活率略有下降。金藻和小球藻是浮游幼虫前期生长适宜的单胞藻饵料。 相似文献
7.
以体长(1.932±0.204)cm、体质量(1.386±0.055)g的棘胸蛙蝌蚪为实验动物,在水温(24±0.2)℃、DO(7.30±0.01)mg/L、pH 7.30±0.01条件下,采用静水停食法开展了氨氮对蝌蚪的急性攻毒实验,并以此为基础,测定了不同氨氮质量浓度胁迫下棘胸蛙蝌蚪的排氨率、耗氧率、氧氮比及窒息点。结果表明:(1)蝌蚪对氨氮急性攻毒具明显的运动避毒行为,濒死个体的背部皮肤和肝脏均具明显的色变症状;(2)氨氮对蝌蚪的急性致死率具明显的剂量—时间效应,24h、48h、72h、96h LC50依次为177.5、151.7、148.6和146.8mg/L,毒性时段蓄积程度系数呈持续下降趋势,24—48h、48—72h、72—96h的时段MAC值分别为84.04%、10.1%和5.86%;(3)蝌蚪夜均、昼均、日均及时段排氨率随氨氮质量浓度增加均呈阶梯式下降趋势,其中时段排氨率与对照组均无显著差异的为9.80mg/L实验组,夜均、昼均、日均及时段排氨率与对照组均无显著差异的仅为2.45mg/L实验组(P0.05);(4)氨氮对蝌蚪呼吸耗氧具低毒兴奋效应,其夜均、昼均和日均耗氧率随氨氮质量浓度增加均呈先升后降趋势,峰值氨氮质量浓度范围均为4.90—7.35mg/L(P0.05),与对照组均无显著差异的仅为14.70mg/L实验组(P0.05),窒息点含氧量随氨氮质量浓度增加呈先降后升趋势,谷底出现于4.90mg/L实验组(P0.05),与对照组无显著差异的仅为9.80mg/L实验组(P0.05);(5)实验期间,蝌蚪氧氮比(O:N)波动于18.87—25.34之间,昼均和日均氧氮比(O:N)随氨氮质量浓度增加均依次呈"上升—稳定—下降—再稳定"之趋势,两者的峰值氨氮质量浓度范围分别为4.90—14.70mg/L和4.90—9.80mg/L,夜均氧氮比(O:N)呈先升后降趋势,峰值出现于7.35mg/L实验组(P0.05)。 相似文献
8.
氨氮急性胁迫对日本沼虾(Macrobrachium nipponensis)死亡率、耗氧率及窒息点的影响 总被引：1，自引：0，他引：1
采用静水停食法,在水温(24.0±0.2)°C、p H(7.61±0.04)条件下开展了氨氮对日本沼虾(Macrobrachium nipponensis)[体长(4.29±0.32)cm,体质量(1.80±0.12)g]的急性毒性实验,并以此为基础测定了不同氨氮质量浓度胁迫下日本沼虾的耗氧率与窒息点。结果表明:(1)氨氮对日本沼虾24h、48h、72h、96h的半致死质量浓度依次为7.922、6.034、4.237和3.371mg/L;(2)鳃是氨氮攻毒日本沼虾的重要靶器官,氨氮对日本沼虾耗氧率的影响具毒物兴奋效应,0.225mg/L为该效应达到峰值的氨氮质量浓度,0.337mg/L为该效应被终止的氨氮质量浓度临界阈;(3)在对日本沼虾耗氧率的影响具毒物兴奋效应的氨氮质量浓度范围内,日本沼虾的窒息点随氨氮质量浓度的梯次升高渐次呈稳定、略增、再稳定之态势,氨氮质量浓度0.112mg/L为致该虾窒息点发生显著改变的临界阈,该实验组窒息点含氧量与对照组无差异(P0.05)。 相似文献
9.
盐度和Ca2+浓度对中国明对虾稚虾耗氧率的影响 总被引：3，自引：0，他引：3
设计双因子实验研究了水温25.0℃±0.5℃下,盐度(5,15,30)和Ca2 质量浓度(175,350,700,1 400,2 800 mg/L)对中国明对虾(Fenneropenaeus chinensis)稚虾耗氧率的影响,实验对虾的湿体质量为0.301 g±0.041 g。实验结果表明:(1)不同盐度下,中国明对虾稚虾耗氧率的大小顺序为R5>R30>R15。其中,盐度15下对虾的耗氧率显著低于盐度5和30下的耗氧率(P<0.05);(2)不同Ca2 质量浓度下,中国明对虾稚虾耗氧率的大小顺序为R2 800>R175>R700>R1 400>R350。其中,Ca2 质量浓度为350 mg/L组对虾的耗氧率显著低于其它处理组,Ca2 质量浓度为2 800 mg/L组对虾的耗氧率显著高于其它处理组(P<0.05),而Ca2 质量浓度为175,700和1 400 mg/L组间对虾的耗氧率差异不显著(P>0.05);(3)盐度和Ca2 质量浓度的交互作用显著影响中国明对虾稚虾的耗氧率(P<0.05)。 相似文献
10.
氨氮和亚硝酸盐对斜带石斑鱼苗的急性毒性效应 总被引：6，自引：0，他引：6
研究了水温(25±0.5)℃,盐度30~31,pH值7.9~8.1,溶解氧4.5~5.5 mg/L条件下氨氮和亚硝酸盐对不同规格斜带石斑鱼(Epinephelus coioides)苗的急性毒性效应。试验结果表明,氨氮对平均全长4.4cm的斜带石斑鱼苗的24、48、72、96 h LC50及安全质量浓度分别为5.62、3.50、2.93、2.68及0.27 mg/L,对应的非离子氨及安全质量浓度分别为0.23、0.14、0.12、0.11及0.011 mg/L;氨氮对平均全长10.5 cm斜带石斑鱼苗的24、48、72、96 h LC50及安全质量浓度分别为58.6、56.2、53.3、51.4及5.13 mg/L,对应的非离子氨及安全质量浓度分别为2.41、2.32、2.20、2.12及0.21 mg/L;亚硝酸盐对全长4.4 cm的斜带石斑鱼苗的24、48、72、96 h LC50及安全质量浓度分别为288.4、281.8、270.4、267.3及26.7 mg/L;亚硝酸盐对全长10.5 cm的斜带石斑鱼苗的24、48、72、96 h LC50及安全质量浓度分别为354.8、346.7、280.5、208.4及20.8 mg/L。 相似文献
11.
Derek V. Ellis 《Marine Georesources & Geotechnology》2001,19(1):51-63
This article reviews information recently available from existing marine and coastal mining for responses to environmental issues affecting marine mining at different depths. It is particularly but not exclusively concerned with those issues affecting seabed biodiversity impact and recovery. Much information has been gathered in the past 10 years from shallow mining operations for construction aggregate, diamonds, and gold, from coastal mines discharging tailings to shallow and deep water, and from experimental deep mining tests. The responses to issues identified are summarized in a series of eight tables intended to facilitate site-specific consideration. Since impacts can spread widely in the surface mixing layer SML, and can affect the biologically productive euphotic zone, the main issues considered arise from the depth of mining relative to the SML of the sea. Where mining is below the SML, the issue is whether it is environmentally better to bring the extraction products to the surface vessel for processing (and waste discharge), or to process the extraction products as much as possible on the seabed. Responses to the issues need to be sitespecific, and dependent on adequate preoperational environmental impact and recovery prediction. For deep tailings disposal from a surface vessel, there are four important environmental unknowns: (1) the possible growth of "marine snow" (bacterial flocs) utilizing the enormous quantities of fine tailings particles (hundreds or thousands of metric tons per day) as nuclei for growth, (2) the possibility that local keystone plankton and nekton species may migrate diurnally down to and beyond the depth of deep discharge and hence be subjected to tailings impact at depth, (3) the burrow-up capability of deep benthos and their ability to survive high rates of tailings deposition, and (4) the pattern and rate of dispersion of a tailings density current through the deep water column from discharge point to seabed. Actions to obtain relevant information in general and site-specifically are suggested. 相似文献
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G. Parthiban 《Marine Georesources & Geotechnology》2000,18(3):223-235
Particle fluxes were measured 7 m above the sea bottom during the predisturbance, disturbance, and postdisturbance periods by using time series sediment traps attached to seven deep-sea moorings deployed in the INDEX experiment site in the Central Indian Basin. The predisturbance particle fluxes varied between 22.3 to 55.1 mg m -2 day -1 . Increased and variable particle fluxes were recorded by the sediment traps during the disturbance period. The increase observed was 0.5 to 4 times more than the background predisturbance fluxes. The increases in particle fluxes (~4 times) recorded by the sediment trap located in the southwestern direction (DMS-1) were the greatest, which could be the result of preferential movement of resuspended particles generated during the deep-sea benthic disturbance along the general current direction prevailing in this area during the experimental period. Also, the traps located closer to the disturbance area recorded greater fluxes than did the traps far away, across the Deep Sea Sediment Resuspension System path. This variability in recorded particle fluxes by the traps around the disturbance area clearly indicates that physical characteristics such as grain size and density of the resuspended particles produced during the disturbance had an important effect on particle movement. The postdisturbance measurements during ~5 days showed a reduction in particle fluxes of ~50%, indicating rapid particle settlement. 相似文献
13.
Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths. 相似文献
14.
海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明：土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。 相似文献
15.
The advanced piston corer (APC) has been used by the Ocean Drilling Program since 1985 for recovering soft sediments from the ocean floor. The pullout force measured on extracting the core barrel from the sediment is shown to correlate with the average shear strength of the sediment core measured in the ship's laboratory. A simple rule of thumb is derived relating the shear strength of the sediment to the pullout force. Multiple APC holes at individual sites allow the consistency of the pullout measurements to be assessed. The effects of different operational procedures during APC coring are also explored. Although generally applicable, the correlation between pullout force and laboratory measurements of shear strength breaks down for some APC holes, possibly because of the disturbance of some sediment types during the APC coring process. A better understanding of the physical process of APC coring, and its effect on the properties of the sediment both inside and immediately outside the core barrel, would indicate what confidence can be put on the measurement of pullout force as a way of evaluating the in situ shear strength of deep sea sediments. 相似文献
16.
Shigehisa Nakamura 《Marine Geodesy》2000,23(1):55-61
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone. 相似文献
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《海洋学报(英文版)》2014,(11):161-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology, 相似文献