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1.
于 2007年11 月~20008年10月对青岛太平角岩石潮间带鼠尾藻附植动物进行了连续12个月的逐月采样调查,并根据蜈蚣藻、角叉菜、扇形叉枝藻、海蒿子和叉节藻等海藻生长期的不同而在不同月份对其分别进行了采样,研究了附植动物的类群组成、丰度、生物量及其季节动态.所有海藻样品共鉴定出附植动物16个类群.鼠尾藻附植动物的年平均丰度为606 ind/g dwt algae,优势类群为线虫和桡足类,其次是腹足类和多毛类.鼠尾藻附植动物的平均丰度最高值出现在4月,最低值出现在7 月 .鼠尾藻附植动物的年平均生物量为282× 103 μg/g dwt algae,最高值出现在6月,最低值为2月.其他海藻附植动物的类群数、丰度、生物量均低于鼠尾藻.海藻附植动物的优势类群及其丰度和生物量在不同月份和不同海藻之间均显著不同.相对于海水理化因 子季节变化的影响,不同海藻生长型形态的复杂性及同一种海藻随生长周期而发生的形态变化对附植动物的区系组成和季节动态的影响能占居更主要地位.  相似文献   

2.
于2007年11月~2008年10月对青岛太平角岩石潮间带鼠尾藻附植动物进行了连续12个月的逐月采样调查,并根据蜈蚣藻、角叉菜、扇形叉枝藻、海蒿子和叉节藻等海藻生长期的不同而在不同月份对其分别进行了采样,研究了附植动物的类群组成、丰度、生物量及其季节动态。所有海藻样品共鉴定出附植动物16个类群。鼠尾藻附植动物的年平均丰度为606ind/gdwtalgae,优势类群为线虫和桡足类,其次是腹足类和多毛类。鼠尾藻附植动物的平均丰度最高值出现在4月,最低值出现在7月。鼠尾藻附植动物的年平均生物量为282×103μg/g dwt algae,最高值出现在6月,最低值为2月。其他海藻附植动物的类群数、丰度、生物量均低于鼠尾藻。海藻附植动物的优势类群及其丰度和生物量在不同月份和不同海藻之间均显著不同。相对于海水理化因子季节变化的影响,不同海藻生长型形态的复杂性及同一种海藻随生长周期而发生的形态变化对附植动物的区系组成和季节动态的影响可能占居更主要地位。  相似文献   

3.
青岛岩礁附植小型底栖动物ATP含量的研究   总被引:5,自引:4,他引:1  
2004年10~12月对青岛太平角潮间带2种海藻(鼠尾藻和羊栖菜)上附生的小型底栖动物进行了连续3个月的采样调查,并进行了附植小型底栖动物优势类群和线虫优势种类ATP含量的测定.2种海藻上共采得12个小型底栖动物类群,平均丰度为518.9nds./g dwt algae,海洋线虫和桡足类为优势类群,两者的相对丰度之和大于84%.鼠尾藻上的线虫ATP含量平均为5.57ng/ind.(以下单位相同),桡足类为4.69;羊栖菜上的线虫ATP含量平均为2.46,桡足类为15.06.共鉴定出海洋线虫28种或分类实体.2种海藻上的线虫优势种类均是刮食食性的三齿棘线虫(Acanthonchus tridentatus).不同粒级海洋线虫的个体干重为0.14~32.65μg/ind.,ATP含量为1.18~297.64ng/ind.,C/ATP比值为43∶1~99∶1.  相似文献   

4.
南麂列岛海洋自然保护区潮间带小型生物初步研究   总被引:3,自引:3,他引:3  
20 0 1年 10月对浙江省南麂列岛国家海洋自然保护区潮间带进行小型生物采样调查。大沙岙沙滩小型生物丰度较低 ,中潮带为 2 91.9ind· 10 cm-2 ,低潮带为 5 16.8ind· 10 cm-2 。线虫是最优势类群 ,线虫 /桡足类比分别为 3.2 7和 1.0 6,表明沙滩环境质量良好 ,未受到有机质污染。岩相潮间带有 4种大型底栖海藻。附植小型生物平均丰度为 36.1ind· g-1dw algae,桡足类为最优势类群。附植大型底栖动物丰度 4 4 .6ind· g-1dwt algae,大于小型生物丰度。  相似文献   

5.
于2004年10月~2005年10月对青岛太平湾砂质潮间带进行了小型底栖生物的逐月采样,对丰度和生物量进行定量研究。结果表明,小型底栖生物的年平均丰度为(1 025.40±268.84)ind.10cm-2,平均生物量为(1 195.87±476.53)μgdwt.10cm-2,平均生产量为(10 762.80±4 288.77)μg dwt.10cm-2a-1。小型底栖生物在丰度和生物量上呈现了明显的季节变化,高值主要出现在4,5,6月,而低值在8,9月。共鉴定出l2个类群,线虫在丰度上占绝对优势(89.2%)。按生物量,多毛类占46.9%,其次为线虫31%。其它较多的类群还有涡虫、桡足类、腹毛虫、寡毛类等。50%以上的小型底栖生物分布在0~4cm表层,冬季部分向下迁移。Pearson相关分析表明,小型底栖生物数量对间隙水溶氧表现出明显的滞后效应,而与盐度、pH和沉积物环境因子相关性不明显。  相似文献   

6.
渤海小型底栖生物的丰度和生物量   总被引:9,自引:1,他引:9  
该文是渤海 1997年 6月、1998年 9月和 1999年 4月 3个航次小型底栖生物调查结果。结果表明 ,3个航次小型底栖生物的平均丰度分别为 :(2 30 0± 12 0 6 ) ind/ (10 cm2 )、(86 9± 5 10 ) ind/(10 cm2 )和 (6 32± 4 0 0 ) ind/ (10 cm2 )。平均生物量分别为 :(15 2 1± 6 34) μg(dwt) / (10 cm2 )、(72 5±35 4 )μg (dwt) / (10 cm2 )和 (5 17± 393)μg (dwt) / (10 cm2 )。共鉴定出 14个小型底栖生物类群 ,其中自由生活海洋线虫丰度占绝对优势 ,桡足类丰度居第 2位 ,这两个类群总和占小型底栖生物总丰度的 94 .8%~ 97.5 %。在生物量中所占比例列前 4位的类群依次为线虫、多毛类、桡足类、双壳类 ,加起来超过小型底栖生物总生物量的 80 %。小型底栖生物的 74 %分布于 2 cm以浅表层中。小型底栖生物的丰度和生物量在渤海海峡和渤海中东部较高 ,与环境因子的相关分析表明小型底栖生物的丰度与水深呈极显著的正相关 ,与沉积物的中值粒径呈显著的负相关  相似文献   

7.
2009年4月14~16日在台湾海峡中北部海域进行了小型底栖生物调查研究.结果表明,研究海域的小型底栖生物平均丰度为21.11±16.29 ind/cm^2;平均生物量为20.97±4.96μg/cm^2(以干重记).研究海域共鉴定出13个小型底栖生物类群,按丰度,最优势类群为自由生活海洋线虫其丰度为19.23±15.49 ind/cm^2,占小型底栖生物总丰度的91.10%,其他优势类群依次为底栖桡足类和多毛类,分别占小型底栖生物总丰度的2.77%和2.64%;分布在0~5 cm的表层沉积物内的小型底栖生物约为83.18%,线虫和底栖桡足类分布在0~2 cm的比例分别为57.66%和62.96%.小型底栖生物的生物量低于大型底栖生物,但由于其繁殖快,生命周期短,因此,其生物量约为大型底栖生物的445倍,年平均生产量约为大型底栖生物的1.39倍.  相似文献   

8.
于2008和2009年对青岛薛家岛砂质潮间带进行了4个季度的小型底栖生物调查。结果表明:小型底栖生物的平均丰度为(1 384.69±424.97)ind·10cm-2,平均生物量为(1 286.70±225.13)μg·10cm-2。共鉴定出11个类群,丰度方面,线虫占绝对优势,占年平均丰度的86.59%;涡虫居次,占4.89%。生物量方面,线虫也占绝对优势,占37.30%;多毛类居次,占18.90%。在垂直分布上,表层0~4cm的数量最多,占39.65%,其它各层分布依次递减。小型底栖生物的丰度和生物量呈现了明显的季节变化和潮区差异。相关分析未表明小型底栖生物丰度和环境的显著相关性。  相似文献   

9.
北黄海小型底栖生物丰度和生物量时空分布特征   总被引:1,自引:0,他引:1  
分别于2006年7月和2007年1,4和10月在北黄海陆架浅海水域进行小型底栖生物调查.结果表明,4个航次的小型底栖生物平均丰度分别为(1 099±634),(664±495),(1 601±837)和(524±378) ind·10 cm-2;平均生物量分别为(1 446.34±764.66),(428.63±294.84),(1 580.53±1 041.23)和(793.50±475.83) μg·dwt·10 cm-2.共鉴定出18个小型底栖生物类群,按丰度,自由生活海洋线虫为最优势类群,4个航次的优势度分别为72%,90%,85%和74%,其他优势类群依次是桡足类、多毛类、动吻类和介形类;按生物量依次是线虫、桡足类、多毛类、介形类和双壳类.97%的小型底栖生物分布在0~5 cm的表层沉积物内,线虫和桡足类分布在0~2 cm沉积物的比例分别为86%和87%.二因素方差分析(two-way ANOVA)表明:小型底栖生物丰度和生物量在由4个航次所代表的春、夏、秋、冬各季节之间存在显著差异(春、夏高于秋、冬),在4个航次的5个相同取样站位之间也有显著差异.小型底栖生物的丰度和生物量与水深和底盐呈负相关性.北黄海冷水团对小型底栖生物丰度和生物量时空分布有一定的影响.  相似文献   

10.
西北太平洋深海小型底栖生物群落结构与分布特点初探   总被引:1,自引:0,他引:1  
小型底栖生物是海洋底栖环境中数量最占优势的类群,但对于其在深海中的类群构成及分布特点还所知甚少。本研究对西北太平洋深海平原的小型底栖生物的主要类群组成及其分布特点进行了解析,并与相邻海域的小型底栖生物群落结构进行了比较分析。调查海域的水深为4080—6066m,共检获14个小型底栖生物主要类群,小型底栖生物的平均丰度和生物量分别为150.8ind./10cm2和100.3μg dwt/10cm2,其中线虫的平均丰度占93.6%。小型底栖生物总体上呈现沿西北至东南方向数量高,该分布趋势与黑潮延伸体影响区域基本吻合,而在黑潮延伸区两侧数量低。绝大多数小型底栖生物分布于沉积物的0—4cm分层, 4—6cm层的小型底栖生物仅占总数的不到10%。本研究中小型底栖生物丰度和生物量均低于相邻深海及冲绳海槽与南海北部深海区的研究结果。小型底栖生物各类群丰度与环境因子的相关性分析显示,小型底栖生物群落组成与沉积物叶绿素a含量和中值粒径显著正相关。生物环境分析(Biota-Environment, BIOENV)结果显示,与小型底栖生物类群结构相关性最高的环境因子组合为水深和沉积物脱镁叶绿素含量。  相似文献   

11.
In order to assess the impact of deep-sea mining on the in situ benthic life, we measured the microbial standing stock and concentration of organic nutrients in the deep-sea sediments of the Central Indian Ocean Basin in the Indian pioneer area. Sediments were collected using box core and grab samples during September 1996. The total bacterial numbers ranged from 10 10 -10 11 cells per g -1 dry weight sediment. There was a marginal decrease in the number of bacteria from surface to 30 cm depth, though the subsurface section registered a higher number than did the surface. The highest numbers were encountered at depths of 4-8 cm. The retrievable number of bacteria were two orders less in comparison with the direct total counts of bacteria. An almost homogeneous distribution of bacteria, total organic carbon, living biomass, and lipids throughout the depth of cores indicates active microbial and benthic processes in the deep sea sediments. On the other hand, a uniform distribution of total counts of bacteria, carbohydrates, and total organic carbon in all the cores indicates their stable nature and suggests that they can serve as useful parameters for long-term monitoring of the area after the benthic disturbance. Further studies on temporal variability in this region would not only verify the observed norms of distribution of these variables but would also help to understand restabilization processes after the simulated benthic disturbance.  相似文献   

12.
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   

13.
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   

14.
An acoustic inversion method using a wide-band signal and two near field receivers is proposed and applied to multiple layered seabed models including a manganese sediment. The inversion problem can be formulated into a probabilistic model comprised of signals, a forward model, and additive noise. The forward model simulates wide-band signals, such as chirp signals, and is chosen to be the source-waveletconvolution plane wave modeling method. The wavelet matching technique, using weighted least-squares fitting, estimates the sediment sound-speed and thickness on which determination of the possible numerical ranges for a priori uniform distribution is based. The genetic algorithm is applied to a global optimization problem to find a maximum a posteriori solution for determined a priori search space. Here the object function is defined by an L 2 norm of the difference between measured and modeled signals. Not only the marginal pdf but also its statistics are calculated by numerical evaluation of integrals using the samples selected during importance sampling process of the genetic algorithm.  相似文献   

15.
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   

16.
The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics.  相似文献   

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《海洋学报(英文版)》2014,(9):F0003-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   

20.
Oedometer tests have been carried out on 70 undisturbed surficial clays (at approximately 250 mm below the mudline), mostly collected by free-fall corers from sites widely scattered throughout the deep-sea North Atlantic. Acoustic measurements were also made, initially on contiguous samples and ultimately on the same sample using a geophysically instrumented oedometer which also collected electrical resistivity data. Apart from those quiescent areas below the carbonate compensation depth, such as north of the West Indies where very fine clays exist, most of the samples are silty clays whose geotechnical-geophysical properties are dependent on the type of clay minerals present (and their ability to take in moisture), the sand-size fraction, and the quantity of carbonate present. Thus the pure clays have high compressibilities which decrease on the addition of coarse particles, while the converse is true for the acoustic parameters, these increasing with the sand fraction. Using the notion of the intrinsic compression line for all samples, and comparison to it of the measured compression curves, it is clear that, contrary to some previously held ideas, most deep-sea clays are normally consolidated; the addition of carbonate has the effect of creating an open, stronger sediment skeleton. Interestingly, where information is available, the variation with depth of a sample's acoustic velocity follows the void ratio pressure relationship of the compression curve. This allows the construction of an in-situ sediment compression curve using the in-situ geophysical observations.  相似文献   

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