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1.
对白骨壤(Avicennia marina)树上的污损动物进行了定性和定量调查。共采得污损动物9种。以白条地藤壶(Euraphia withersi)和潮间藤壶(Balanus littoralis)在多数采样点的附着密度最高,但二者在树上的分布有明显的差异;团聚牡蛎(Ostrea glomerata)分布最广,是惟一~种在各采样点均能采到的污损动物;黑养麦蛤(Xenostrobus atraus)主要分布在树干和较粗的枝条上,其密度在向海林缘达到最大,超过牡蛎和藤壶的附着密度。污损动物附着高度与树高的比值(h:H),主干、枝条和叶片上附着的污损动物总量均随林带离岸距离增大而增大,呈明显的变化趋势。  相似文献   

2.
九龙江口红树林上附着动物的生态   总被引:12,自引:2,他引:12  
周时强  洪荣发 《台湾海峡》1993,12(4):335-341
福建九龙江口红树林附着动物7种,白脊藤壶Balanus albicostatus和白条地藤壶Euraphia withersi在数量上占绝对优势,是危害红树的主要附着动物。附着动物在河口红树林区的数量分布随着盐度的降低而减少,其栖息密度和生物量的高峰期在夏,秋两季。生长茂密的红树林(郁蔽度大于0.5),附着动物主要分布于水流畅通的向海边缘和潮沟边缘的红树上。水流畅通程度是影响附着动物在红树林区向纵  相似文献   

3.
对1998年6月南海北部20天的海流和温度定点连续观测资料进行分析,得到该海域内潮的特征及其能量分布。分析结果显示内潮的主要成分为O1,K1,M2与S2分量,其中全日内潮(O1与K1)的能量占主要部分。在观测期间,此四个分量的海流失量均为顺时针旋转,其潮流椭圆半长轴的最大值超过14cm/s。海水温度的变化显示出内潮存在准日周期振动,平均垂向振幅达到50m。观测到的内潮携带高能量且其活动存在不连续性,在观测范围内,全日内潮的动能及势能密度的最大值分别达到2kJ/m^2及3.5kJ/m^2,半日内潮的动能及势能密度的最大值分别达到1kJ/m^2及1.5kJ/m^2。  相似文献   

4.
秦皇岛近海褐潮高发区浮游植物的碱性磷酸酶活性分析   总被引:1,自引:0,他引:1  
碱性磷酸酶(Alkaline phosphatase,AP)是浮游植物在磷胁迫状态下表达的一种水解有机磷源的胞外酶,可用于指示海区浮游植物的磷胁迫状态。本研究于2013年7月,对秦皇岛近海抑食金球藻(Aureococcus anophagefferens)褐潮发生期间浮游植物的碱性磷酸酶活性(AP activity,APA)进行研究,结合其他理化参数,分析藻华发生时浮游植物的磷营养状态及其对海水中磷源的水解与利用情况。结果表明,褐潮发生时,抑食金球藻细胞密度高达108个/L,溶解有机磷(Dissolved organic phosphorus,DOP)成为浮游植物生长利用的主要磷源。抑食金球藻的细胞密度受到海水中NO3–、DOP、溶解无机磷(Dissolved inorganic phosphorus,DIP)浓度等的显著影响。浮游植物大量表达AP水解DOP,平均APA高达217.72 nmol/(μg·h)±90.86 nmol/(μg·h)(350.44 nmol/(L·h)±130.57 nmol/(L·h)),且APA随浮游植物生物量增大而显著增加。该结果表明抑食金球藻褐潮发生时,海区遭受严峻的磷胁迫甚至限制。磷源,尤其是有机磷源的可利用性可能在秦皇岛海区抑食金球藻褐潮的发生和维持中起关键作用。  相似文献   

5.
应用厦门内湾东西3个口门断面(五通—下店、嵩屿—鼓浪屿、鼓浪屿—轮渡)一个潮周日走航ADCP资料的空间插值潮、流调和分离结果,分析占主导的M2分潮流与余流沿断面的空间分布特征.分析结果表明受地形约束的3个断面M2分潮流均以往复流为主,断面深槽为主流通道,M2分潮最大可能流速均沿主流深槽向左右岸递减,三断面中以鼓浪屿—轮渡断面最为强劲,平均值为46 cm/s,五通—下店断面次之为43 cm/s,嵩屿—鼓浪屿断面最弱,仅为33 cm/s.该半日潮波进入厦门内湾首先在鼓浪屿—轮渡断面达到最大值,出现时间在月中天后2.1 h,其次为五通—下店断面2.7 h,最后为嵩屿—鼓浪屿断面3.3 h.再者地形变化剧烈的嵩屿—鼓浪屿断面M2分潮非线性运动较强,浅水分潮的幅度增大.潮波的非线性效应又衍生了非周期性的潮致余流,该余流在厦门内湾东西口门有较为稳定的存在,且表现为近岸区流幅大,潮流通道内小,嵩屿—鼓浪屿与鼓浪屿—轮渡断面均值为9 cm/s,五通—下店断面均值为5 cm/s,同时各个断面余流均存在使内湾海水正常更替,沿断面法向一分为二,一进一出的态势.基于本次观测结果计算出一潮周日厦门内湾东西口门余流通量为76.156×10^6m3,净潮通量为69.591×10^6m3,相对偏差小于8.6%.  相似文献   

6.
基于2020年夏季的大面航次观测数据,分析了烟台—威海北部海洋牧场及邻近海域海水溶解氧浓度垂向分布最小值(氧最小值层)的空间分布特征,并探讨了影响因素。从6月至8月,海水溶解氧浓度不断减小,垂向结构亦存在显著变化。海水溶解氧浓度垂向分布的最小值主要集中于7月的近岸海域,最小值大致从外海向近岸方向减小,其距离海底高度及与底层溶解氧浓度之差的绝对值均于双岛湾邻近海域为最大。海水溶解氧浓度垂向分布的最小值位于最强密度层结以下。但是海水溶解氧浓度垂向分布最小值的强度向北减小,而密度层结向北增大,两者的空间分布基本相反,说明密度层结抑制垂向湍流扩散可极大减少深层海水溶解氧的来源,是海水溶解氧浓度垂向分布最小值形成的必要条件,但不是主导因素。在海水溶解氧浓度垂向分布的最小值层,表观耗氧量存在垂向分布的最大值,大部分站点的pH存在垂向分布的最小值,说明局地增强、持续的生物地球化学耗氧是控制海水溶解氧浓度垂向分布最小值形成和空间分布的一个重要过程。研究结果表明氧最小值层是夏季烟台—威海北部近岸海水溶解氧垂向结构的典型特征之一。  相似文献   

7.
浙江北关港污损生物的群落结构及其主要影响因子   总被引:1,自引:1,他引:0  
于2016年3月至2017年2月在浙江北关港附近海域进行污损生物周年挂板试验,全年共记录大型污损生物9门44科53属59种,种类组成以近岸暖水种为主,属于典型的亚热带内湾型污损生物群落。固着生活类型的悬浮物食者是该海域污损生物群落的优势群体,群落最主要的优势种是网纹藤壶(Amphibalanus reticulates),其次为长鳃麦秆虫(Caprella equilibra)、中胚花筒螅(Ectopleura crocea)、太平洋侧花海葵(Anthopleura nigrescens)、廉形叶钩虾(Jassa falcata)和强壮藻钩虾(Stenothoe valida)等种类。该海域污损生物全年各月均有附着,6-10月板的覆盖面积均达100%,附着盛期为6-8月,月板、季板、半年板和年板的平均附着密度和生物量分别为(21 371±8 722) ind/m2和(1 667.5±506.0) g/m2,(31 605±17 671) ind/m2和(5 879.1±2 576.5) g/m2,(31 188±10 834) ind/m2和(13 989.6±4 755.4) g/m2,(18 425±5 757) ind/m2和(6 581.9±2 175.9) g/m2,其中夏季附着强度最高。污损生物群落个体间因栖息空间和食物竞争而存在着相互依存或互相制约的关系,又依照对环境的适应性而存在着一定的时空分布规律。分析表明,温度是决定污损生物地理分布的最主要环境因素;另外,盐度、水体透明度以及光照等自然环境也是影响污损生物附着的重要影响因素。  相似文献   

8.
应用短期资料的潮流准调和分析方法,对后水湾网箱养殖区五测站两周日海流观测获得的表、中、底层海流资料进行了分析,计算了五测站O1、K1、M2、S2、M4、MS46个主要分潮的潮流调和常数,并给出了各测站在各层的潮流椭圆要素。计算结果表明:后水湾主要为日潮流海区,从最北的海区边缘向湾内靠近避风锚地,潮流性质由不规则全日潮流变为不规则半日潮流;从湾口到湾内,各分潮北分量基本以全日潮流K1为主,其次为全日潮流O1和半日潮流M2,主要分潮的振幅逐渐降低,且越靠近湾内,浅水分潮的作用越大;各分潮东分量仍以全日潮流为主,但半日潮流的作用增大,可以达到与全日潮流相当的作用。观测期间最大余流值基本出现在中层,且处于两个开边界的F1和F5站位的余流值明显大于其它站位;各站位的表层余流基本指向西北-北-东北向,即朝向湾外;而中、底层余流基本指向西南-南-东南向,即朝向湾内,通过上、下层海水的运动,海区内物质最终可以向湾外输运。整个海区可能最大流速表层在29~70 cm/s之间;中层在43~62 cm/s之间;底层在30~47 cm/s之间。表层海水基本为逆时针的旋转流运动;而中、底层海水由于一直受到邻昌礁的约束,基本为往复流运动。  相似文献   

9.
本研究首次探究了西太平洋雅浦海沟北段从表层到超深渊海水中甲烷(CH4)及二甲基硫(DMS)的前体物质二甲基巯基丙酸内盐(DMSP)的浓度变化情况。结果表明:雅浦海沟海水甲烷浓度变化范围为1.49~3.87 nmol/L。其上层海水甲烷平均浓度最高,有明显的次表层极大现象。雅浦海沟氧最小层海水的甲烷平均浓度最低;在500~1 000 m中层水中甲烷浓度有一定程度的增大,1 000 m以下至底层甲烷浓度继续升高。研究海区溶解态DMSP(DMSPd)和总DMSP(DMSPt)平均浓度的垂直变化随深度呈先增大后减小趋势,颗粒态DMSP(DMSPp)的平均浓度随深度呈波动式变化,在中层达到最大。雅浦海沟CH4和DMSP浓度垂直变化受浮游生物、微生物、光照、温度、压力、大洋环流等的复杂影响。在真光层海水中,CH4浓度与DMSPd、DMSPp和DMSPt浓度表现为负相关关系,在200 m至底层海水中,CH4浓度与DMSPd、DMSPp和DMSPt浓度表现为正相关关系,显示光照条件是造成雅浦海沟不同深度海水CH4和DMSP浓度相关性差异的关键因素。  相似文献   

10.
几个试验因子对细巧华哲水蚤清滤率和滤食率的影响   总被引:6,自引:0,他引:6  
以象山港浮游桡足类优势种细巧华哲水蚤(Sinocalanus tenellus) 成体为试验动物投喂以大溪地等鞭金藻(Isochrysis galbona),对其清滤率F(ml/个.h)和滤食率G(细胞/个.h)进行了实验测定,结果表明,温度,海水比重,食物浓度及试验动物密度的变化对细巧华哲水蚤清滤率和滤食率均有显著影响,水温15度,比重1.-1-,食物浓度150000个细胞/ml和试验动物密度.25个/ml的条件下,细巧华哲水蚤滤食率达到最大。  相似文献   

11.
Tidal flooding and surface drainage patterns have often been used to describe mangrove species zonation. However, in mangrove forests exhibiting little topography, ambiguous species distributions and/or few species, such approaches are ineffective. We identified four physiognomic mangrove forest types (Riverine, Fringing, Overwash and Basin) at Coombabah Lake, a tidal lake in southeast Queensland, Australia and investigated tidal flooding patterns using synoptic surveys of tidal observations at the local Standard Port combined with local water depth observation. Subsequently three sub-types of the basin forest type were identified: (1) Deep Basin Forest with mature trees, ∼50 cm standing water and ∼3 tides per year; (2) Medium Depth Basin Forest with intermediate tree development, ∼15–30 cm standing water and 20–40 tides per year; and (3) Shallow Basin Forest with relatively recent mangrove establishment, 5–15 cm standing water and ∼80 tides per year. These three basin sub-types were found to flood at different tide heights with the Shallow Basin flooding for tides above mean high water springs and the Deep Basin flooding only for tide heights approaching the highest astronomical tide. We propose that these basin types represent a succession in mangrove forest development that corresponds with increasing water depth and tree maturation over time. The succession not only represents increasing age but also change in basin substrate composition. This is manifest as increasing pneumatophore density and an increasing area of basin surface occupied by contiguous pneumatophore cover. As a result, it seems that mangrove development is able to modify tidal flooding into the basin by increasingly impeding water movement.  相似文献   

12.
The utilisation of a brackish estuarine marsh by nekton was investigated over a semi-lunar cycle in August 1994. Nekton migrating in and out of the intertidal creeks of the marsh ‘Het Verdronken Land van Saeftinghe’ in the Westerschelde estuary, SW Netherlands, was sampled passively during seven complete tidal cycles. Sampling one tidal cycle yielded three consecutive flood samples and four consecutive ebb samples. Sampling occurred every 2–3 days, covering diel, tidal and semi-lunar situations, thus allowing comparison of tidal, diel and semi-lunar influences on the composition of the intertidal fauna.Two different tidal-migration modes were observed. The mysid shrimp, Mesopodopsis slabberi, showed maximum abundance around high tide. For the remaining common species, the mysid (Neomysis integer), the shrimp (Palaemonetes varians), the crab (Carcinus maenas) and the goby (Pomatoschistus microps) and the amphipod (Corophium volutator), highest densities were recorded during lower water heights. The faunal assemblage shifts between the different tidal stages.On two occasions, consecutive day and night samples were taken. Total densities were higher during the night samples. During spring tide, difference in community composition was noticed between the night and the day samples. During neap tide, day–night differences were less clear. Recorded total densities were highest during spring tide and lowest during neap tide. At maximum water levels, a drop in total density was observed. A shift in community composition occurred between spring and neap tides.  相似文献   

13.
The morphology and mobility of bedforms within a sand wave field having a water depth of 30 to 40 m have been studied by side-scan sonar surveys at different tidal stages and under various wave climates. Large sand waves with heights of 4 to 7 m retained their orientation throughout the survey period, Small sand waves with heights less than 2 to 3 m changed their height over a tidal cycle and their location (relative to larger sand waves) between surveys. The maximum change appeared to be related to ebb current acceleration. Megaripple wavelengths were reduced under surface wave action.  相似文献   

14.
胶州湾辛岛潮间带大型底栖动物生态学调查   总被引:3,自引:1,他引:3       下载免费PDF全文
利用2003年8月至2004年5月(夏、秋、冬、春季)4个季度月在胶州湾辛岛潮间带的3个不同潮区的调查资料进行分析。结果共获得大型底栖动物43种,其中低潮区出现27种,中潮区和高潮区20种和19种,有6种属于3个潮区共有种。大型底栖动物总平均栖息密度为102.5个/m2,5月最高,为144.67个/m2,2月最低,为52.66个/m2;总平均生物量为60.01g/m2,11月最高,为102.99g/m2,2月最低,仅为11.87g/m2。本区大型底栖动物的栖息密度和生物量有明显的季节变化。  相似文献   

15.
我国南方强潮海岸红树植物对潮流的调制作用   总被引:2,自引:0,他引:2  
至今,关于红树植物对潮流的调制作用的研究非常有限,尤其是红树植物对垂向流速剖面的影响还不清楚。本研究利用自主研发的自动升降架于大潮期间对浙江南部乐清湾西门岛秋茄种植区的红树林滩进行垂向多点观测。结果表明,在所研究的红树林内,整个垂向剖面的流速普遍较低。树干和冠层引起的拖曳力在垂向上的增加,使得红树林内垂向流速剖面呈现"流速随距底高度增大而减小"的规律。此外,湍流能量密度在垂向上也呈现出与红树植物垂向结构相对应的变化。与光滩(半对数)和盐沼(近"J"形)内流速的垂向结构相比,红树植物以一种不同的方式对垂向流速剖面产生重要影响。  相似文献   

16.
HDPE深水网箱抗风浪流性能的海区验证试验   总被引:5,自引:0,他引:5  
吴常文  朱爱意  沈建林 《海洋工程》2007,25(2):84-90,97
对HDPE深水网箱2000~2004年间的抗风浪流性能进行了海区验证试验.通过对HDPE深水网箱扶栏、框架、网具以及固泊系统受损率的统计,根据扶栏、框架、网具以及固泊系统在整个深水网系统中的重要程度,分别给予一定的权重统计出深水网箱的整体受损率,能比较客观地反映深水网箱的抗风浪流性能.海区验证试验结果表明,HDPE深水网箱抗风力达35 m/s、抗浪高6 m、抗流速1.0 m/s,与其设计参数基本相同.同时,为了增加HDPE深水网箱的抗风浪流性能,建议扶手管从110 mm改为125 mm、主浮管从250 mm改为300 mm、扶栏高度从1 m降低为0.8 m或0.6 m.风力主要影响扶栏系统,流速主要影响网具系统,而波浪对HDPE圆形浮式深水网箱的框架、网具、固泊系统以及网箱整体结构均有明显影响.  相似文献   

17.
In this work we evaluated the vertical distribution pattern of benthic infauna during the tidal cycle at one of the most important mudflats of the Tagus estuary. Samples were collected hourly during 24 h periods at four complete tidal cycles, using a corer specifically designed for the study purpose that allowed easy and effective separation of 15 different sediment layers. A particular case of general linear models, the hurdle model, was used to analyse data sets. We found that different species have different distribution and abundance according to sediment layers. Results showed that individuals tend to go deeper into sediment with a lower water column height and that these migrations are more visible during spring tides.  相似文献   

18.
Significant variations of phosphate and silicate concentrations have been observed in seawater from selected industrial pipelines at intake depths between 400 and 710 m off the Hualien coast, eastern Taiwan, revealing a strong vertical movement of water mass in this intermediate layer. An intensive monitoring experiment was carried out, in which pipeline seawater from three land-based pumping stations and seawater collected by a research vessel were obtained and analyzed in parallel during a 2-day observation period. The results showed clearly that the changes of nutrient concentrations in both pipeline and shipboard samples followed a semidiurnal cycle. The maximum vertical displacement occurred in the 300–800 m layer with a scale as surprisingly large as 100 m, when compared with that observed in other areas. The tidal cycles for different layers may not synchronize with surface tide or each other. Empirical equations have been implemented between nutrient concentrations and temperature for the Hualien off-shore area. The equation can be used to check temperature variation of the intermediate water by measuring either phosphate or silicate in pipeline seawater.  相似文献   

19.
Results of direct measurements of the long-wavelength (LW) radiative heat influx (RHI) in the atmospheric surface layer (ASL) are presented. These measurements were performed in August 2003 at the IAP RAS base in Tsimlyansk under the conditions of unstable and stable stratification during a weak wind and a cloudless sky and under nonsteady conditions during cumulus cloudiness in the daytime. The underlying surface was dry steppe with spars grass. The in situ RHI measurements were performed with an original optoacoustic receiver having a quasi-spherical angle of view at heights from 0.15 to 4 m. It is shown that the radiative heating in the ASL was many times the actual heating, especially during near-noon hours. In the daytime, the radiative heating attained its maximum at the heights of measurements 0.15–1 m and decreased with height. The radiative heating at these heights in the near-noon hours was on average about 20 K/h, attaining 60 K/h under a cloudless sky and a weak wind. Under inversion stratification, the radiative cooling usually exceeded the actual cooling, amounting on average from 0 to ?8 K/h and changing with height only slightly. Periods with close (in phase) fluctuations of the radiative and actual cooling, sometimes changing to heating, were observed during the night. Regression equations, showing a high correlation between the RHI values at the heights of measurements 0.5 and 1 m and the soil-air temperature differences at the height of measurements, are obtained for different heights. The diurnal mean RHI profiles are characterized by a heating on the order of several K/h in the lower part of the layer of measurements, which decreases with height and changes to cooling at heights of up to 4 m. A change in the effective radiation with height in the layer of measurements, which was obtained through the summation of RHI values at several heights, was significant, attaining on average ?25 W/m2 in the near-noon hours and +10 W/m2 in the evening hours. The nonradiative (turbulent) heat influx, obtained as the difference between the rates of actual and radiative temperature variations measured in situ, decreased the radiative heating in the daytime many times. The main sources of error in direct RHI measurements are estimated.  相似文献   

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