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海草污染生态学研究进展 总被引:2,自引:0,他引:2
本文对国外近20年来在海草污染生态学方面的研究成果进行了综述。这些成果主要包括重金属、农药和石油对海草的影响。重全属时海草影响的研究重点.是重金属对海草生理功能的影响,以及海草对重金属的富集等方面;农药对海草的影响研究.集中于其对海草的生理学和形态学方面的影响。以及海草对农药的耐性等;而石油对海草的影响研究.主要是事故性石油污染和石油分散剂对海草的影响。最后,本文展望了该领域今后的研究重点与方向。 相似文献
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The sway, heave and roll added masses of three uniform cylinders with semi-circular, rectangular and triangular cross-sectional shapes in shallow and narrow water are numerically analysed. The method is based on simulation of the potential flow induced by the cylinder's mode of motion. The effects of shallow and narrow water on added mass are analysed and presented. It is concluded that the shallow and narrow water effects on added mass depend on the different cross-section shapes of the cylinders. In particular, the water depth effect on sway added mass is stronger than that on heave added mass while the narrow water effect on sway is weaker than that on heave. The shallow water effect on added mass tends to weaken the narrow water effect. Lastly the effect of shallow and narrow water on added mass on a rectangular cylinder is the strongest while that on a triangular cylinder is the weakest. 相似文献
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On rocky shores, the relative importance of abiotic and biotic processes that regulate community structure are thought to vary with levels of shore exposure. This can lead to characteristic features found on sheltered and exposed shores. This study identified differences in the population structure of mussels on exposed and sheltered rocky shores on Atlantic coasts of south-west Ireland. Direct interactions between epibiotic algae and their host mussels were also examined to test if potential effects varied with shore exposure. Mussel beds on sheltered shores were less dense and comprised larger mussels with greater rates of individual survival and growth than those on exposed shores. The results of a field experiment showed that algal epibionts had a negative effect on mussel survival on sheltered shores but not on exposed shores. Surprisingly, the presence of algal epibionts had no effect on mussel growth on either shore type. These findings contrast with those of previous studies. The effects of shore exposure and algal epibionts on mussels may be species-specific and may interact with other factors across different regions. This study shows that predictions of effects of exposure on mussel populations and their epibionts should only be based on specific experimental evidence and cannot be generalised across regions. 相似文献
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南麂列岛潮间带的微小型底栖藻类 总被引:4,自引:0,他引:4
本文首次记录南麂列岛国家级海洋自然保护区潮间带的微小型底牺藻类。经初步鉴定南麂列岛潮间带共有微小型底栖藻类4门54属155种,以硅藻类占优势(41属125种)。其优势种在岩礁为附生性的海生斑条藻,沙滩为附生性的小形舟形藻和翼茧形藻,泥滩为底栖性的圆筛藻和斜纹藻。不同生境其种类组成差异显著,在各生境均出现的共有种仅6种。微小型底栖藻类年平均丰度:岩礁为7094.61个/g,沙滩为46821.63个/g,泥滩为456.5个/g,岩礁和沙滩以春季最高;泥滩以夏季最高;秋、冬季各生境的丰度均较低。 相似文献
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附着基粗糙度等因素与海藻密度的相关性研究 总被引:1,自引:0,他引:1
海藻附着基表面粗糙度与孢子附着密度有密切的相关性;已经由许多研究证实。但是海藻苗的密度是否仍然受到附着基粗糙度的影响;还缺乏明确的结论。本文以尼龙和亚克力两种材料作为海藻附着基;悬挂于自然海区中使海藻孢子附着并萌发生长;用以研究附着基表面粗糙度对4种海藻密度的影响。结果显示;多管藻、尾孢藻、点叶藻、硬毛藻这4种海藻;在不具沟槽的光滑面;密度显著低于任何有沟槽的粗糙面;但粗糙度不同的附着基之间比较;对海藻密度的影响并不显著。室内培育的海带苗;在尼龙上的密度与粗糙度成正相关;但是将海带苗移至海上培育后;不再与粗糙度有相关性;可能与其假根状固着器下海后的发育有关。本文还试验了海泥、灭活海泥和低栖硅藻3种沉积物与附着基粗糙度对海藻密度的影响;结果表明;沉积物和附着基粗糙度;以及它们的交互作用对海藻密度的影响;因附着基的材料和海藻种类而有差别。 相似文献
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Little is known about the effects of offshore energy installations on the marine environment, and further research could assist in minimizing environmental risks as well as in enhancing potential positive effects on the marine environment. While biofouling on marine energy conversion devices on one hand has the potential to be an engineering concern, these structures can also affect biodiversity by functioning as artificial reefs. The Lysekil Project is a test park for wave power located at the Swedish west coast. Here, buoys acting as point absorbers on the surface are connected to generators anchored on concrete foundations on the seabed. In this study we investigated the colonisation of foundations by invertebrates and fish, as well as fouling assemblages on buoys. We examined the influence of surface orientation of the wave power foundations on epibenthic colonisation, and made observations of habitat use by fish and crustaceans during three years of submergence. We also examined fouling assemblages on buoys and calculated the effects of biofouling on the energy absorption of the wave power buoys. On foundations we demonstrated a succession in colonisation over time with a higher degree of coverage on vertical surfaces. Buoys were dominated by the blue mussel Mytilus edulis. Calculations indicated that biofouling have no significant effect in the energy absorption on a buoy working as a point absorber. This study is the first structured investigation on marine organisms associated with wave power devices. 相似文献
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世界各海沿岸的潮间带大部分区域是沙滩,这主要是由于波浪的强烈冲击所致。与碎石、石砾滩一样,沙滩对底栖生物的生存显然不利,因而其栖息生物种类比较贫乏,数量也少,完全缺乏大型植物,除了某些特定的沙栖种外,主要是一些小型无脊椎动物和植物。河口附近和内湾水下平台则例外,丰富的有机物质使之成为完全不同的生境。
虽然潮间带生态研究已有一百多年的历史,但有关沙滩生境的研究较少,对沙滩生物的生态特点缺乏系统的探讨。有的学者直接采用岩岸潮间带生态研究方法,这不仅与客观实际不符,而且造成术语上的混乱。另外,在群落结构的研究中也存在不少问题,例如往往没有按生态特点区别底内生物和底表生物,造成对区系性质的错误判断。为此,我们想通过对小场沙滩生境的调查研究,对沙滩潮间带研究中的一些问题进行初步探讨。 相似文献
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Time series of velocity and water temperature were measured at three stations on the continental shelf, on the shelf margin and on the slope off the northwest Tokunoshima in December 1980 to study influences of the slope on tides.Tidal currents with semidiurnal periods were dominant at the stations on the shelf and shelf margin. However, semidiurnal components in temperature fluctuations were dominant at the stations on the shelf margin and the slope. We estimated horizontal currents due to semidiurnal internal tides from the vertical distribution of water density and temperature, assuming that the temperature fluctuations were caused by the vertical displacement of water particles due to semidiurnal internal tides. The tidal ellipses at the station on the shelf and the phase relation of the tidal currents between the two stations on the shelf and shelf margin indicated that the M2 surface tide on the shelf was a Sverdrup wave propagating to the northwest.Semidiurnal tidal currents on the slope were also caused by tides of surface and internal modes. Furthermore, the axis of the tidal ellipse was not perpendicular to the co-tidal line estimated by Ogura (1934) but rather parallel to the isobaths on the slope, which shows a striking effect of the bottom topography on the tidal currents. 相似文献
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随着北极海冰融化的加剧,北极问题研究的重要性逐渐凸显。文章以ScienceDirect数据库为主要搜索范围,系统梳理了2007—2021年国外北极问题研究文献,从北极航线、北极经济、北极政治和北极环境4个方面对国外北极问题研究现状进行了分析。认为未来的国外北极问题研究中,北极航线相关问题研究将聚焦于北极航线运营模式的研究;北极经济问题研究将注重区域经济和北极产业发展;北极政治研究依然会着力探讨如何在北极治理中的合作问题,虽然目前的北极政治研究中定性分析和描述性分析较多,但未来将增加定量分析和理论创新的研究;北极环境问题研究将注重北极经济开发和环境保护的平衡,进一步关注北极的可持续发展问题。 相似文献
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为研究低氧胁迫对军曹鱼幼鱼免疫功能的影响,将幼鱼暴露于溶氧浓度为(3.15±0.21) mg/L的水体28 d,测定不同时间点肿瘤坏死因子α (TNFα)、肿瘤坏死因子α诱导蛋白3 (TNFAIP3)、白细胞介素1β (IL-1β)、白细胞介素1受体2 (IL-1R2)、白细胞介素17C (IL-17C)和热休克蛋白70 (HSP70)等免疫相关基因在幼鱼鳃、肝脏、肠道和脾脏中的转录水平表达量。结果显示:(1)在幼鱼的鳃中,TNFα 和 IL-1R2 基因转录水平表达量在胁迫1 d和14 d时极显著低于对照组(p<0.01),胁迫 28 d则分别表现为极显著(p<0.01)和显著下降(p<0.05);TNFAIP3在胁迫1 d时极显著升高(p<0.01),在胁迫7 d和14 d时则分别表现为显著(p<0.05)和极显著(p<0.01)下降;IL-1β在胁迫1 d时极显著下降(p<0.01)后极显著升高 (p<0.01);IL-17C在胁迫7 d和14 d时极显著下降(p<0.01);HSP70 在胁迫1 d时显著下降(p<0.05),在胁迫14 d和28 d时均极显著降低(p<0.01);(2)在肝脏中,TNFα 和 IL-1R2 基因转录水平表达量在胁迫1 d和28 d时显著下降(p<0.05),在胁迫14 d时则极显著降低(p<0.01);TNFAIP3在胁迫1 d时极显著上升(p<0.01),在胁迫14 d和28 d时则极显著下降(p<0.01);IL-1β在所有胁迫时间点均极显著上升(p<0.01);IL-17C 在胁迫7 d、14 d和28 d时均极显著低于对照水平(p<0.01);HSP70基因表达量持续上升,并于胁迫28 d时达到顶峰(p<0.01);(3)在肠道中,TNFα、IL-1β、IL-1R2、IL-17C和HSP70基因转录水平表达量在胁迫的所有时间点均极显著高于对照组(p<0.01),TNFAIP3在胁迫1 d时表达量极显著升高(p<0.01)后下降,在胁迫7 d和14 d时分别与对照组具有显著(p<0.05)和极显著差异(p<0.01);(4)在脾脏中,TNFα和IL-17C 基因转录水平表达量在胁迫1 d、7 d和14 d时极显著下降(p<0.01),在胁迫28 d时则显著降低(p<0.05);IL-1β在胁迫1 d和28 d时极显著下降(p<0.01),在胁迫7 d和14 d时则显著降低(p<0.05);IL-1R2在胁迫1 d、7 d和28 d时极显著下降(p <0.01),在胁迫14 d时则显著下降(p<0.05);HSP70基因表达量在胁迫1 d、7 d和28 d时均极显著下降(p<0.01)。研究结果表明,28 d的低氧胁迫后,军曹鱼幼鱼免疫基因的转录表达水平发生显著性变化,预示长时间的低氧可能抑制了军曹鱼的免疫功能,引发肠道炎症,并增加了军曹鱼感染病原菌的风险。 相似文献
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波浪的方向分布对波浪的传播及其与工程结构物的作用都具有明显影响,目前现有的研究大多是基于单向波浪进行的。为了研究方向分布对群墩结构上的爬高影响,基于规则波浪与群墩作用的理论解,结合多向不规则波浪的造波方法,建立了多向不规则波浪与群墩作用的计算模型,同时进行了物理模型试验对模型的有效性进行了验证。系统地对群墩周围及表面上的波浪爬高进行了计算分析,结果表明,方向分布对波浪爬高具有较大的影响,且不同位置处的影响并不相同,在实际的工程设计中如果按照单向波浪计算,可能低估或者高估群墩周围的爬高。 相似文献
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Tuna-farming is expanding worldwide, necessitating the monitoring/managing of its effects on the natural environment. In Japan, tuna-farming is conducted on coral reefs that have been damaged by mass-bleaching events and crown-of-thorns starfish (COTS) outbreaks. This study focused on the coral community on an artificial substrate of tuna-farm to reveal the possible effects of tuna-farming on the natural environment. Corals flourished on ropes suspended in the farm in the Amami Islands, southern Japan. These were moored 3 m below the sea-surface in 50-m-deep water. The coral community on the rope was analyzed and compared with those on natural substrata on two adjacent COTS-damaged reefs and with that in a protected reef. Corals were monitored throughout a year. Sixty coral species grew on the ropes, that corresponds to 27.3% of the 220 species known from Amami. The coral community was unique, dominated by massive faviid corals. On the ropes, the water temperature rarely exceeded 30.0 °C and no corals on the rope were severely bleached or covered by sedimentation during the observations. The tuna-farm infrastructure provided corals with a suitable habitat, and species-rich coral communities were established. These coral communities are an important node connecting tuna-farms and the natural environment. 相似文献
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薛春汀 《海洋地质与第四纪地质》2002,22(2):121-125
珊瑚礁海岸海滩和礁坪是海岸作用是活跃的部分,也是近几十年来与海岸发育,海岸侵蚀联系最密切的部分,这一部分高潮时被淹没,低潮时完全出露或大部分出露,使得在此进行地质填图成为可能,这样的地质图可以提供许多信息,如沉积物粒度分布规律,沉积物来源和搬运方向,海滩岩所指示的古海岸线位置,人类活动特别是海岸工程对沉积物分布的影响以及海岸线的变化过程和趋势,在礁坪上开挖的人工水道内测流,能够了解水流的性质以及是否有足够的速度搬运沉积物,从而了解人工水道对海岸的影响和预测海岸的状态,这些方法也可以用于大陆泥质和砂质第岸侵蚀的研究。 相似文献
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星载微波辐射计外定标的关键问题是通过辐射传输方程计算天线入瞳处亮温。根据辐射传输方程,海面成份对亮温的影响包括海面的微波辐射和对下行大气辐射的反射,其中的关键参数分别为海面发射率ep和海表面反射率R。文中对平静海面Fresnel反射率模式和粗糙海面反射率模式进行了研究分析,在此基础上着重研究了海面温度TS、海面盐度SS、海面风速W、以及观测角度θ等物理参数对海面发射率ep的影响,进而分析了这些物理参数的测量误差对亮温的计算精度的影响。 相似文献
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