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1.
Underwater video reveals decreased activity of rocky intertidal snails during high tides and cooler days 
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下载免费PDF全文 Nearly all of our understanding of rocky inter‐tidal ecology comes from studies conducted at low tide. To study inter‐tidal organisms at high tide, we anchored waterproof digital GoPro® video cameras in wave‐exposed tidepools and recorded the daytime movements of the black turban snail, Tegula funebralis, over the tidal cycle between May and August 2012 near Bodega Bay, California. Overall, snails moved more quickly and presumably foraged more during low tides and on days with warmer air and perhaps water temperatures. This is similar to other ectotherms that exhibit increased metabolic rates, movement and foraging in warmer conditions. Snails also moved less during flood and high tides, may have moved downward in tidepools at flood tides, and showed evidence of reduced activity on days with larger waves. This inactivity and refuge seeking may have been a strategy to avoid dislodgment by waves. Analysis of snail trajectories showed foraging bouts indicated by alternating zig‐zagging and straight movement. There was no effect of temperature, wave height, or tidal phase on distribution of snail turning angles, suggesting that they may have foraged consistently but moved faster during warm conditions and low tides, thereby grazing a larger area. This is one of few direct recordings of inter‐tidal organisms on wave‐exposed rocky shores during high tide. The methods used here are easily transferable to other studies, which are needed to increase our understanding of behaviors that structure rocky shore communities during high tide. 相似文献
2.
Influence of rock‐pool characteristics on the distribution and abundance of inter‐tidal fishes 下载免费PDF全文
下载免费PDF全文 Rock pools can be found in inter‐tidal marine environments worldwide; however, there have been few studies exploring what drives their, fish species composition, especially in Australia. The rock‐pool environment is highly dynamic and offers a unique natural laboratory to study the habitat choices, physiological limitations and adaptations of inter‐tidal fish species. In this study rock pools of the Sydney region were sampled to determine how the physical (volume, depth, rock cover and vertical position) and biological (algal cover and predator presence) parameters of pools influence fish distribution and abundance. A total of 27 fish species representing 14 families was observed in tide pools at the four study locations. The five most abundant species were Bathygobius cocosensis, Centropogon australis, Enneapterygius atrogulare, Lepidoblennius haplodactylus and Microcanthus strigatus, which together represented 71% of the total number of fish recorded. Larger rock pools containing more algal and rock ledge cover hosted a larger and more diverse population of fish. Furthermore, certain species were only found in pools with specific characteristics, such as the presence of loose shells, a variety algae or rock cover, suggesting a high degree of habitat specificity. By contrast, some species were ubiquitous and thus can likely tolerate a wide variety of physical conditions. 相似文献
3.
南黄海西北部夏季潮锋的观测和分析 总被引：3，自引：1，他引：2
根据2001-2004年逐年6月多学科综合调查资料和同期NASA的MODIS/Terra卫星遥感SST资料,对南黄海西北部夏季潮锋的不连续分布现象做了分析;并通过三维潮流数值模式计算Simpson-Hunter参数(以下简称S-H参数)分布,对不连续分布的形成机制做了讨论.层化季节南黄海西北部的苏北浅滩-海州湾外侧和山东半岛东部的成山头-石岛外海存在显著潮锋现象,而在两海域之间、青岛以东的山东半岛南部121°~122°E的近岸海域无显著潮锋持续存在;较高分辨率的潮流数值模拟的结果表明潮锋的不连续性分布主要是由潮混合和地形的共同作用而形成.潮锋不连续处海域潮混合较弱,层化现象更为显著.南黄海西北部底层锋形态较为显著,位于通过潮流模式计算的Simpson-Hunter参数1.8~2.4之间,与2.2等值线分布较为一致;表层锋则在海州湾外侧和石岛沿岸海域较为明显.潮锋不连续的分布特征对该海域的生态环境造成一定的影响,叶绿素a、中华哲水蚤、鳀鱼卵子等的数量分布都在潮锋显著的苏北浅滩-海州湾外侧和成山头-石岛外海海域形成较为密集的分布. 相似文献
4.
Shell‐shape and morphometric variability in Mytilus galloprovincialis from micro‐tidal environments: responses to different hydrodynamic drivers 下载免费PDF全文
下载免费PDF全文 Tidal conditions differently influence inter‐tidal organisms in terms of general physiological and metabolic responses. In this study we investigated the morphological response in shells of Mytilus galloprovincialis native to different micro‐tidal coastal environments in the Northern Adriatic Sea. Our purpose was to highlight the ecophenotypic variability across tidal levels and to elucidate how tidal currents and waves produced by anthropogenic activities may play a part in modulating shell morphology. Three sampling sites were selected: an open‐sea area 15 km off‐shore and two sites within the lagoon of Venice, the first near one of its three inlets, and the other one in the proximity of Venice city centre. At each sampling site, organisms were seasonally collected at different depths within their vertical zonation, either in the inter‐tidal zone – i.e. at both the highest and lowest tide zonation limits, and subtidally. The mussel shells were analysed by investigation of their morphometric relationships (height/length and width/length ratios) and by elliptic Fourier analysis of the shell contours. Shell thickness and condition index were also evaluated for a better comprehension of energy allocation/partitioning. Estimates based on long‐term measurements, visual observation, wind statistics and wave growth laws allowed an evaluation of the forces acting on shells. At the open‐sea site, the observed phenotypic variability of both shell shape and thickness was clearly related to the tidal vertical zonation. At the two lagoon sites, the currents generated by tidal flow through the inlet and the waves caused by the frequent passage of boats influenced both shell shape and thickness. A trade‐off between protection and growth was apparent along the tide gradient, as emphasized by the differences in the partitioning and allocation of energy between shell and flesh production. 相似文献
5.
南麂岛附近海域潮汐和潮流的特征 总被引：4，自引：2，他引：2
以2008年冬季在浙江近海南麂岛附近投放的4个底锚系观测的水位和流速资料为依据,分析了潮汐和潮流特征。水位谱分析结果显示半日分潮最显著,全日分潮其次;近岸的浅水分潮比离岸大。水位调和分析结果表明:潮汐类型均为正规半日潮,近岸处的平均潮差大于3m,最大可能潮差大于6m,潮汐呈现出显著的低潮日不等和回归潮特征。流速谱分析结果显示半日分潮流最强,全日分潮流其次,且比半日分潮流小得多;近岸浅水分潮流比远离岸显著。流速调和分析结果表明:潮流类型均为正规半日潮流,靠近岸的两个站浅水分潮流较显著;最显著的半日分潮流是M2分潮流,其最大流速介于0.32～0.48m/s之间,全日分潮流均很弱,最大流速小于0.06m/s。M2分潮流均为逆时针旋转,椭圆率越靠近海底越大;最大分潮流流速分布为中上层最大、表层略小、底层最小;最大分潮流流速方向的垂向变化很小,底层比表层略为偏左;最大分潮流流速到达时间随深度的加深而提前,底层比中上层约提前30min。潮流椭圆的垂向分布显示这里的半日分潮流以正压潮流为主;日分潮流则表现出很强的斜压性。 相似文献
6.
Tidal currents derived from current meter measurements are compared with the output from a barotropic tidal model of the New Zealand region. For the semi‐diurnal constituents there was very good agreement for the M2 tide and good agreement for the S2 tide. For the diurnal constituents (Kl, Ol) it was found that as the amplitude of the constituents decreased so did both the model/observation agreement and the accuracy of the observed tidal ellipse parameters. Consequently it was not possible to decide whether differences arose through shortcomings in the model or in the data. However, the overall performance of the model as a prognostic tool for ocean tidal current simulation appears to be good. 相似文献
7.
Tidal variation in a rocky inter‐tidal fish population: the case of white seabream Diplodus sargus juveniles 下载免费PDF全文
下载免费PDF全文 Ana Ribeiro Gonçalves Liliana de Sousa Pedro Duarte‐Coelho Vitor Carvalho Almada 《Marine Ecology》2015,36(4):1468-1471
The rocky inter‐tidal habitat is a harsh and fluctuating environment, subject to frequent disturbances. Field observations of juvenile white seabream Diplodus sargus in inter‐tidal rocky habitats were conducted to analyse the spatial distribution and feeding activity of this species in relation to the tidal cycle. The depth at which fish were observed did not change in most tidal phases while feeding activity changed with tidal level, showing the occurrence of tidal migrations and that feeding may be limited by habitat availability in shallow waters and thus be dependent on tidal changes. The present results show the exploitation of available feeding areas in the rocky inter‐tidal by juvenile white seabream, which corroborates the importance of these habitats for the first developmental stages of this fish species. 相似文献
8.
海湾内外的潮波变形及其不对称性影响海湾内外动力输送和水体交换。利用乐清湾内外共9个测站连续潮位进行调和分析,得到该海湾内外各分潮变化规律,利用潮不对称性偏度计算方法确定湾内外潮汐不对称性时空变化特征,比较了主要分潮组合对潮汐不对称性的贡献度,通过数值研究探讨了湾内偏度比湾外偏度值更小的主要成因,分析了湾内外围垦工程对潮不对称偏度的影响。研究发现:乐清湾内潮汐不对称偏度值为负,表现为落潮占优,同期湾外洞头站偏度值为正,与邻近瓯江、飞云江河口的潮不对称偏度变大、表现涨潮占优的变化规律相反;湾外沿岸各站偏度由东北向西南逐渐增大,由落潮占优向涨潮占优变化;潮汐不对称性偏度呈周期性变化,分析确定M2-M4、M2-S2-MS4分潮组合对潮不对称贡献大,该海域潮汐不对称的强度主要由浅水分潮振幅控制,而相对相位则决定潮汐不对称的方向;数值研究探讨表明,湾内大范围的浅滩地形是其潮汐不对称落潮占优的主要原因,围垦将削弱湾内的落潮占优。 相似文献
9.
象山港潮滩坡度对潮动力影响的数值研究 总被引：2，自引：0，他引：2
象山港属于狭长型半封闭港湾，湾内分布有大面积潮滩。多年以来象山港内实施了大量海岸工程及养殖工程，湾内潮滩坡度发生了显著变化。基于非结构网格和有限体积数值模式（FVCOM）建立象山港三维潮动力模型，研究湾内不同区域潮滩坡度变化对象山港潮动力过程的影响机理。结果表明：潮滩坡度下降将增大湾内纳潮量，进而增大M2分潮振幅和迟角，反之则反。铁港潮滩坡度的减小（增大），将改变底部耗散项，进而增大（减小）M4分潮振幅。由于M2和M4分潮的振幅在湾顶较大，所以湾顶（铁港）潮滩坡度对象山港潮动力过程的影响明显大于侧岸（西沪港）。西沪港潮滩坡度对象山港潮动力过程的影响是局部的。铁港、西沪港潮滩坡度对湾内潮汐不对称、余流及潮能影响显著。铁港潮滩坡度的改变均会减弱湾内落潮占优程度。西沪港区域潮滩坡度的减小将减弱湾内落潮占优趋势，反之则反。铁港和西沪港潮滩坡度的减小，将增大余流大小及潮能密度，进而潮能耗散增大，反之则反。研究结果对河口海岸潮滩区域的工程建设及生态修复有重要参考价值。 相似文献
10.
Distribution pattern of zooplankton in the han river estuary with respect to tidal cycle 总被引：1，自引：0，他引：1
The monthly distribution of zooplankton communities in Han River estuary was investigated at two stations from July 1998 to
June 1999. Monthly mean abundance of total zooplankton varied remarkably, with the range from 20 indiv.·m-3 to 19,600 indiv.·m-3. During the study period, dominant species of zooplankton community were dinoflagellateNoctiluca scintillans, copepodsParacalanus indicus, Paracaanus crassirostris, Acartia hongi, Acartia ohtsukai, and meroplanton cirriped larvae. According to tidal states, relative high abundance occurred at high tide without regard
to season. The temporal distribution of abundance implied that the reduced salinity probably limited the zooplankton populations
and the fluctuations of salinity were an important factor in the variation of abundance. However, the results of salinity
tolerance test shows that the variations in salinity do not directly influence the decrease of abundance. This study shows
that the relatively high abundance of zooplankton near high tide seems to be related with the expansion of abundant zooplankton
inhabiting Incheon coastal waters through tidal currents. 相似文献
11.
The tidal regime of Shark Bay, Western Australia 总被引：1，自引：0，他引：1
Murray C. Burling Charitha B. Pattiaratchi Gregory N. Ivey 《Estuarine, Coastal and Shelf Science》2003,57(5-6):725-735
A non-linear hydrodynamic model is used to describe the tidal dynamics of Shark Bay, Western Australia. The model is forced by tidal elevations generated by M2, S2, K1 and O1 constituent data at the open boundaries. The absence of suitable boundary data required a ‘calibration’ of the boundary condition against the known constituent data from within the model domain. The model provides a good match to the available field data, and allows the surface-level and current response to be resolved over the entire domain. Due to a near quarter-wave resonance of the semi-diurnal tide along the eastern Hopeless Reach, which increases the semi-diurnal tide by a factor of 2, the tidal characteristics on each of the Reaches are different: on the eastern Hopeless Reach the tides are mainly semi-diurnal while on the western Freycinet Reach the tides are mainly diurnal. The tidal range is also higher along Hopeless Reach. Tidal harmonics, generated by non-linearity, are important in the shallow regions. The tidal wave is shown to propagate as a progressive wave into the Bay. Substantial phase-lag, attenuation and dissipation occur over the Faure Sill, a major shallow region of the eastern reach of the Bay. Non-linear generation of the M4 and MS4 tides is also significant in this region. Depth-averaged residual currents are presented, which show a tidally generated circulation that is enhanced in regions of complex topography. Estimates of tidal dissipation indicate that although the total dissipation is small on a global scale, the areal average is comparable with the Gulf of Carpentaria and approximately one-quarter of the value estimated for the Patagonian Shelf. 相似文献
12.
珠江三角洲径潮相互作用下潮能的传播和衰减 总被引：2，自引：2，他引：0
因径流潮汐相互作用,三角洲各水道的能通量包含径流引起的净通量及潮汐引起的潮能通量。本文利用珠江三角洲多断面实测水位及流量的同步测量数据,建立基于径潮耦合的调和分析模型,剥离径流信号,计算出各站的总潮能及M2、K1及高频浅水分潮的潮能,对珠江三角洲潮能的沿程传播及衰减进行研究。结果表明,通过虎门进入珠江三角洲的潮波能量约占51.2%,而通过崖门、蕉门、磨刀门传入三角洲的潮能约占37%;同时,因地形摩擦、径流耗能效应,三角洲各水道的总能量损耗为148.33 MW。潮波能量按汇聚型和分散型两大类型沿三角洲不同位置传播并沿程衰减。虎门狮子洋及珠江正干、崖门至潭江石咀两大水道体系,其潮能沿程分散传入不同汊道,断面总潮能的衰减幅度大于单宽潮能通量的衰减,单宽潮动能沿程平均衰减速率大于潮势能,半日分潮的潮能衰减速率大于全日分潮。虎门狮子洋因其形态影响,M2分潮振幅（或势能）的衰减最小,虎门至泗盛围段增加,平均每千米约增加0.77%。西四口门潮能汇聚于西海水道天河断面,总潮能的衰减速率小于磨刀门水道单宽潮能衰减速率。沿横门、洪奇门、蕉门进入的潮波多次交汇、分散,自横门至小榄、南华,南沙至海尾、荣奇,其单宽潮动能及M2、K1分潮动能的衰减速率小于潮势能,高频分潮势能沿程增加。 相似文献
13.
Suzanne E. Hollins Scott F. Heron Peter V. Ridd 《Estuarine, Coastal and Shelf Science》2009,82(4):615-620
The typically anaerobic nature of mangrove sediments provides significant challenges to the mangrove trees and biota inhabiting them. The burrowing activities and flow of water through the numerous and complex animal burrows perforating the sediments of mangroves have a major influence on the biogeochemistry of the sediments and are important to the enhancement of nutrient and oxygen exchange. Two new methods are presented for monitoring the tidal flushing of Sesarma messa and Alpheus cf macklay burrows in a Rhizophora stylosa mangrove forest – by measuring oxygen content of burrow water and by determining the change in fluorescence of a dye tracer through tidal inundation. A case study using the first of these showed oxygen consumption rates at the burrow wall deep within the burrow were found to be between 210 and 460 μmol O2 m−2 h−1. The influx of oxygen during a flood tide was found to be significant and indicated that approximately 40% of the burrow water is flushed during a single tidal event. However, the high consumption rate of oxygen within the burrow resulted in the oxygen concentration remaining at or below one-third of the oxygen content of the flooding tidal water. A test application of the second method, using rhodamine dye as a tracer, indicated that the exchange of water between the burrow and the flooding tide was found to be in the order of 30% of the burrow volume. These new techniques provide a means to further study the nutrient exchange within these burrow systems and verify the initial findings that several tidal inundations are necessary to completely flush the burrows. 相似文献
14.
Channel constrictions within an estuary can influence overall estuary-sea exchange of salt or suspended/dissolved material. The exchange is modulated by turbulent mixing through its effect on density stratification. Here we quantify turbulent mixing in Hikapu Reach, an estuarine channel in the Marlborough Sounds, New Zealand. The focus is on a period of relatively low freshwater input but where density stratification still persists throughout the tidal cycle, although the strength of stratification and its vertical structure vary substantially. The density stratification increases through the ebb tide, and decreases through the flood tide. During the spring tides observed here, ebb tidal flow speeds reached 0.7?m?s?1 and the buoyancy frequency squared was in the range 10?5 to 10?3?s?2. Turbulence parameters were estimated using both shear microstructure and velocimeter-derived inertial dissipation which compared favourably. The rate of dissipation of turbulent kinetic energy reached 1?×?10?6?m2?s?3 late in the ebb tide, and estimates of the gradient Richardson number (the ratio of stability to shear) fell as low as 0.1 (i.e. unstable) although the results show that bottom-boundary driven turbulence can dominate for periods. The implication, based on scaling, is that the mixing within the channel does not homogenise the water column within a tidal cycle. Scaling, developed to characterise the tidal advection relative to the channel length, shows how riverine-driven buoyancy fluxes can pass through the tidal channel section and the stratification can remain partially intact. 相似文献
15.
A combination of a three-dimensional hydrodynamic model and in-situ measurements provides the structures of barotropic tides,
tidal circulation and their relationship with turbulent mixing in the Java Sea, which allow us to understand the impact of
the tides on material distribution. The model retains high horizontal and vertical resolutions and is forced by the boundary
conditions taken from a global model. The measurements are composed of the sea level at coastal stations and currents at moorings
embedded in Seawatch buoys, in addition to hydrographic data. The simulated tidal elevations are in good agreement with the
data for the K1 and M2 constituents. The K1 tide clearly shows the lowest mode resonance in the Java Sea with intensification around the nodal point in the central region.
The M2 tide is secondary and propagates westward from the eastern open boundary, along with a counterclockwise amphidromic point
in the western part. The K1 tide produces a major component of tidal energy, which flows westward and dissipates through the node region near the Karimata
Strait. Meanwhile, the M2 tide dissipates in the entire Java Sea. However, the residual currents are mainly induced by the M2 tide, which flows westward following the M2 tidal wave propagation. The tidal mixing is mainly caused by K1 tide which peaks at the central region and is consistent with the uniform temperature and salinity along the vertical dimension.
This mixing is expected to play an important role in the vertical exchange of nutrients and control of biological productivity. 相似文献
16.
Cathy H. Lucas 《Journal of Sea Research》2003,50(4):301-308
Observations of resuspended diatoms in the shallow waters (<60 cm) of the turbid tidal edge are described for single sites on two tidal flats–the Molenplaat in the Westerschelde estuary, and the Hond in the Ems-Dollard estuary, The Netherlands. High concentrations of chlorophyll-a (chl-a) were observed in the trailing edge of the ebbing tide in water depths of <20 cm, after which concentrations decreased markedly. Peak mean values were 19 μg chl-a l−1 in 10 cm of water at the Molenplaat, and 45 μg chl-a l−1 in 5 cm of water at the Hond. Similar trends were observed on the flooding tide, although peak values were far less pronounced (6 and 30 μg chl-a l−1 respectively). Microscopic examination of the diatom community within the turbid tidal edge at the Molenplaat revealed that peaks in biomass were caused by suspended benthic diatoms, as well as the large centric diatom Coscinodiscus sp., particularly on the ebb tide. Planktonic diatoms other than Coscinodiscus sp. were more randomly distributed and did not appear to follow any particular trend. It would seem that as the tide recedes, resuspended benthic diatoms and large Coscinodiscus sp. cells become concentrated in the shallow water. However, the virtual absence of Coscinodiscus sp. from the leading edge of the flooding tide suggests that most of the resuspended cells do not settle to the seabed, but are washed away into the channels. The small peak of benthic diatoms at the leading edge of the flood tide is most likely resuspended locally from the sediment, along with large numbers of diatom frustules. 相似文献
17.
Daisuke Inazu Tadahiro Sato Satoshi Miura Yusaku Ohta Kazuyuki Nakamura Hiromi Fujimoto Christopher F. Larsen Tomoyuki Higuchi 《Journal of Oceanography》2009,65(3):335-347
An accurate prediction of ocean tides in southeast Alaska is developed using a regional, barotropic ocean model with a finite
difference scheme. The model skill is verified by the observational tidal harmonics in southeast Alaska including Glacier
Bay. The result is particularly improved in Glacier Bay compared to the previous model described by Foreman et al. (2000). The model bathymetry dominates the model skill. We re-estimate tidal energy dissipation in the Alaska Panhandle
and suggest a value for tidal energy dissipation of 3.4 GW associated with the M2 constituent which is 1.5 times the estimation of Foreman et al. (2000). A large portion of the M2 energy budget entering through Chatham Strait is dissipated in the vicinity of Glacier Bay. Moreover, it is shown that the
developed model has the potential to correct the ocean tide loading effect in geodetic data more efficiently than the model
of Foreman et al. (2000), especially around Glacier Bay. 相似文献
18.
The design and operation of mathematical models of solute mixing and sediment transport in estuaries rely heavily on the provision of good-quality field data. We present some observations of salinity, suspended sediment concentration and velocity at one of the tidal limits of a semi-enclosed tidal lagoon in Southern England (Pagham Harbour, West Sussex, UK) where the natural processes of tidal incursion and solute mixing have been heavily modified as a result of the construction of sea walls dating back to the 18th Century. These observations, made immediately downstream of two parallel tidal flap gates by conductivity-temperature-depth (CTD) profiler, and also using bed-mounted sensor frames to measure velocity at 2 fixed depths, have yielded a set of results covering 11 tidal cycles over the period 2002–04. It is clear from the results obtained that over a typical tidal cycle, the greatest vertical salinity gradients occur in the 1–2 h immediately after the onset of the flood tide, and that subsequently, energetic mixing acts to rapidly break down this stratification. Under moderate-to-high fresh water flows (>0.5 m3/s), the break-down in vertical salinity gradient is more gradual, while under low fresh water flows (<0.2 m3/s), the vertical salinity gradient is generally less pronounced. Estimates of Richardson number during the early flood-tide period reveal values that vary rapidly between <1 and about 20, with lower values occurring after around 1.5–2 h after low water. Observations of suspended sediment concentration vary widely even for similar tidal and fresh water flow conditions, revealing the possible influence of wind speed, the storage effects of the water in the lagoon downstream of the observation site, and the complexity of the hydrodynamics downstream of tidal flap gates. The data also show that most of the sediment transport is landward, and occurs during flood tides, with estimated total tidal landward flood tide flux of fine sediment of the order of 50–120 kg under low fresh water flow conditions. These observations, which reinforce the results presented in Warner et al. (2004) and elsewhere, can help to provide information about the appropriate techniques for managing sediments and pollutants, including nutrients from sewage effluent waters, in estuaries where hydraulic flap gates are used to control the entry of fresh water over the tidal cycle. 相似文献
19.
Structural integrity of Ellisolandia elongata reefs: A mechanical approach to compare tensile strengths in natural and controlled environments 下载免费PDF全文
下载免费PDF全文 Federica Ragazzola Paride Fabbri Matteo Scafè Maurizio Florio Matteo Nannini Chiara Lombardi 《Marine Ecology》2017,38(5)
Geniculate coralline algae are oases of biodiversity, providing nursery areas and shelter for the species that live amongst their fronds. The key to their success in the inter‐tidal is the ability to withstand hydrodynamic forces. Under culturing conditions most of the physical and ecological stressors such as intense hydrodynamic forces and grazing are extremely reduced, thus affecting species mechanical properties and their response to external threats. The aim of the present study was to investigate tensile mechanical properties of clusters of fronds of Ellisolandia elongata from natural (sheltered and exposed reef) and culturing conditions (after 1 month of culturing). The tensile test showed that the first failure stress (σI) was not significantly different between the natural and culturing conditions, indicating that the two reefs (sheltered and exposed) were characterized by the same distribution of pre‐existing, inherent structural flaws. Interestingly, the σmax (maximum stress before rupture) was significantly different between the two conditions, with the culturing condition being more resistant to average load compared to the natural conditions. The maximum stress before rupture (σmax) showed the influence of the environment in reducing the strength and elasticity of the fronds. 相似文献
20.
基于FVCOM的泉州湾海域三维潮汐与潮流数值模拟 总被引：1，自引：0，他引：1
基于FVCOM海洋数值模式,采用非结构的三角形网格和有限体积法,建立了泉州湾海域高分辨率(26 m)的三维潮汐、潮流数值模型。模拟结果同2个验潮站和3个连续测流站的观测资料符合良好,较好地反映了泉州湾内潮汐、潮流运动的变化状况和分布特征,给出了M2、S2、K1、O1 4个主要分潮的同潮图、表层潮流椭圆分布,以及模拟区域内最大可能潮差、表层最大可能潮流流速和潮余流分布。分析表明,4个分潮的最大潮汐振幅和迟角差分别为219 cm和19°,85 cm和25°,26 cm和12°,26 cm和9°;石湖港以东海域的潮波为逆时针旋转的驻波,以西海域为前进波;最大可能潮差由湾口的8.0m向湾内增加至8.8 m。湾内潮流类型为规则半日潮流,落潮最大流速大于涨潮最大流速,北乌礁水道为强流区,表层最大可能潮流流速为2.4 m/s;湾口潮流运动以逆时针方向的旋转流形式为主,湾内的潮流运动以往复流形式为主,长轴走向主要沿着水道方向,与等深线和海岸线平行;四个分潮流表层最大流速分别为1.4 m/s,0.58 m/s,0.12 m/s,0.10 m/s。余流流速大小与潮流强弱有密切的联系,表、中、底层最大余流流速分别为26 cm/s,20 cm/s,16 cm/s,三者在水平方向基本呈北进南出的分布形态。 相似文献