潮坪层序的粒度特征与沉积相划分--以杭州湾庵东浅滩为例

现代潮滩依据多年平均潮位线划分高、中、低潮滩，这对于古代潮坪沉积相研究无实际意义。本文尝试用潮坪层序粒度参数剖面来划分沉积相。潮坪沉积物以粉砂为主，但敏感地反映沉积动力变化的却是粗、细尾部分。因此，在沉积相划分时主要依据粘土、砂含量及平均粒径的变化特征。分选系数是一重要依据，但要考虑絮凝沉积的影响。偏态和峰态变幅小、较复杂，在相划分中只具参考价值。利用粒度参数剖面进行潮坪沉积相划分可广泛应用于古代潮坪层序研究，而且根据中潮坪沉积厚度(x)与平均潮差(y)存在的显著性相关关系：y=1．8314x 157．31(单位cm)，推算古潮差。     

Growth dynamics of eelgrass, Zostera marina, in the intertidal zone of Seomjin Estuary, Korea

To examine the growth dynamics of eelgrass, Zostera marina, in the intertidal zone of Seomjin Estuary, Korea, we surveyed environmental factors such as water temperature, underwater irradiance, tidal exposure, and nutrient concentrations in the water column and sediment pore water in relation to the shoot density, biomass, morphological characteristics, and growth of Z. marina inhabiting the upper and lower intertidal zones. The survey was conducted monthly from January 2003 to December 2004. The water temperature of the two areas displayed seasonal fluctuations. Underwater irradiance was significantly higher in the upper intertidal zone than in the lower intertidal zone. Tidal exposure was also markedly longer in the upper intertidal zone than in the lower intertidal zone, whereas tidal exposure was highest in the spring and lowest in the summer in both areas. Water column NH₄ ⁺ and sediment pore water NO₃ ^?+NO₂ ^? concentrations were significantly higher in the upper intertidal zone than the lower intertidal zone. The eelgrass shoot density, biomass, morphology, and leaf productivity were significantly higher in the lower intertidal zone than in the upper intertidal zone. Both areas displayed a clear seasonal variation depending on changes in water temperature. However, leaf turnover time was significantly shorter in the upper intertidal zone than in the lower intertidal zone, with a higher turnover rate in the upper intertidal zone. Compared to the seagrasses in the lower intertidal zone, those in the upper intertidal zone showed more effective adaptations to the stress of long tidal exposure through downsizing and increased turnover time. These results suggest that tidal exposure, coupled with desiccation stress, can be a limiting factor for seagrass growth in the intertidal zone, along with underwater irradiance, water temperature, and nutrient availability.     

Cumulative subject index volumes 34–38, 1980

The coast of the State of Kuwait is characterized by a relatively wide intertidal flat area. At the north, where it is close to Shatt-al-Arab estuary, the intertidal sediments are mainly fluviomarine, while open marine sediments dominate the southern intertidal flat area. Samples were examined from the intertidal zone of deposition from the fluviomarine and open marine environments.The sediments consist mainly of carbonate minerals (low-Mg calcite, high-Mg calcite, aragonite and dolomite), quartz, feldspars, clay minerals and heavy minerals. The mineralogy of the clay fractions of the sediments is dominated by illite, mixed-layer illite—montmorillonite, montmorillonite, chlorite, kaolinite and palygorskite with only minor amounts of quartz. Heavy minerals are concentrated in the very fine sand fraction and are dominated by opaque minerals, amphiboles, pyroxenes, epidotes, garnet, kyanite and sillimanite. Zircon, tourmaline, andalusite, staurolite and rutile are present in subordinate amounts.Three main sources are suggested for the intertidal sediments of Kuwait: (a) Shatt-al-Arab fluviatile deposits, (b) aeolian dust fallout, and (c) direct chemical and biogenic precipitation from the Gulf water.     

Spatial distribution of zooplankton in the intertidal marsh creeks of the Yangtze River Estuary,China

Zooplankton are important grazers of primary production within intertidal marshes and are the optimal prey of higher trophic consumers; however, the patterns of their spatial distribution in marsh creeks are rarely reported. The zooplankton in the intertidal creeks with different salinities at Dongtan marshes of the Yangtze River Estuary was surveyed. The mean zooplankton densities in the intertidal creeks were 53,638 ind. m⁻³ in April and 132,916 ind. m⁻³ in July, respectively, which were as high as in the near-shore subtidal waters of the Yangtze River Estuary. This high abundance implied the important roles of zooplankton in the matter flux between marshes and near-shore waters through complex intertidal creek systems. Zooplankton total densities changed significantly from northern to southern creeks. ANOSIM and CCA analyses revealed that the zooplankton community structure were significantly different among the northern, eastern and southern creeks, and between two sampling seasons. Salinity accounted for most of the spatial variation of zooplankton community, whereas water temperature, chlorophyll a concentration, and pH were the main reasons of the temporal variation observed. Copepods were the most abundant zooplankton group. A total of 24 copepod species, belonging to 15 families and 20 genera, were recorded. Planktonic copepods preferred the northern and eastern creeks, with higher densities in July than in April, while benthic copepods predominated only in the northern creeks in April. Since the role of benthic and planktonic copepods may differ in transporting nutrients in the intertidal creeks, it is suggested that the variations in their distribution may influence the ecological functions of zooplankton in the estuarine matter fluxes both spatially and temporally.     

Evidence of the restricted gene flow within a small spatial scale in the Japanese common intertidal goby Chaenogobius annularis

Elucidating the scale of gene flow among populations is an important challenge for understanding the ecological dynamics and local adaptation of marine organisms. We assessed whether gene flow is restricted even at a small spatial scale in the Japanese common intertidal goby Chaenogobius annularis, using highly polymorphic DNA markers, involving the mitochondrial DNA (mtDNA) control region and 15 microsatellite DNA (msDNA), because past ecological studies have suggested low dispersal ability for rocky intertidal fishes. We found significant heterogeneities between four neighboring local populations by both mtDNA and msDNA analyses. In addition, no genetic heterogeneity was detected by either method across generations within a population; it was considered that such genetic differentiation is retained across generations and that the gene flow of this species is restricted to within a radius of a few kilometers. This is the first report showing a clear genetic subdivision in rocky intertidal fish.     

Invasive Spartina alterniflora-induced factors affecting epibenthos distribution in coastal salt marsh, China

Artificially introduced cordgrass, Spartina alterniflora, rapidly colonized the intertidal flats of the Jiangsu coast, eastern China. The epibenthos on an intertidal flat invaded by S. alterniflora were studied, to identify how local epibenthos species react to an altered environment. Epibenthic samples and surficial sediment samples were collected along a shore-normal profile in 50 quadrats at ten stations across the Spartina salt marsh; and five control quadrats for a station located on the barren sandy-mud flat. The grain size parameters of the surficial sediments show that S. alterniflora altered the grain size gradient along the profile of the intertidal zone by trapping fine-grained sediments. Spartina alterniflora could inhabit lower elevations than indigenous salt marsh vegetation, thus creating larger areas of finer surficial sediments, which was suitable for not only native epibenthic species but also species which do not exist on the barren sandy-mud flat. Correlation analyses show that the epibenthos were sensitive to sediment grain size and type, on the invaded S. alterniflora salt marsh. Further, there was an interspecific relationship affecting the distribution of epibenthos. The results show that epibenthos preferred ecological niches, within the Spartina salt marsh, even in the same sampling station.     

Clay mineralogy of Quaternary sediments in the Wash Embayment,eastern England

The Wash is an area of extensive intertidal flat sedimentation. Samples were examined from the intertidal zone of deposition and also from areas that are probable sources of the sediments being deposited.The mineralogy of the clay fractions of the sediments is dominated by illite, mixed layer illite-montmorillonite, montmorillonite, kaolinite and chlorite with only minor amounts of quartz and calcite. There is no apparent difference in the qualitative nature of the clay minerals found in the sediments. There is also little or no significant variation in the relative proportions of the clay minerals in the modern intertidal flat sediments. However, variations are found between the relative proportions of clay minerals present in the probable source materials and the intertidal flat sediments.Evans (1965) proposed that the main sources of the intertidal sediments are via erosion of the floors of the North Sea and the Wash, and the exposed coasts of Lincolnshire and Norfolk. Whilst accepting these as primary sources, the clay mineral data indicate that erosion and redeposition of the intertidal flat material is a further important source of clay grade sediments.     

Morphodynamics of intertidal bar morphology on a macrotidal beach under low-energy wave conditions, North Lincolnshire, England

The morphological changes of multiple intertidal bars (ridges) on a macrotidal beach were examined under low-energy wave conditions during a spring-to-spring tidal cycle. The morphological response was coupled to the tidal water level variations and related residence times for swash processes and surf (breaking waves and bores) over the cross-shore profile. Spring tides induced a large spatial variation in water lines and small residence times for distinct processes. Neap tides narrowed the intertidal area and increased the time for certain processes to work on the sediment at one location. The observed morphological changes could be coupled to the stagnation of processes at a certain bar crest position. The action of surf (breaking waves and bores) played the major role in the onshore migration of the intertidal bars and the simultaneous erosion of the seaward flank. Swash action, responsible for the generation and migration of intertidal bars in microtidal settings, was not the dominant process in causing the observed morphological changes. Intertidal ridges on macrotidal beaches cannot be considered swash bars as suggested by most previous investigations into these morphological features.     

Distribution,Population Structure, ­Population Biomass and Morphological Characteristics of the Tunicate Pyura stoloniferain the Bay of Antofagasta,Chile

Abstract. The present study analyzes the distribution, population structure, population biomass and morphological characteristics of the intertidal tunicate Pyura stolonifera (Heller, 1878) in the Bay of Antofagasta, Chile, where the species shows a reduced geographical range extending around 60 – 70 km. Three sites along its distribution were studied. At the central site the tunicate presents the widest intertidal belts, reaching nearly 11 m (the mid‐intertidal‐Pyura‐zone shows the higher percent cover). Population dry biomass here averaged up to 20.45 kg·m^–2, representing one of the highest intertidal specific biomasses reported in the literature. Lower values occur towards the borders of its distribution. Population densities were over 1800 indiv.·m^–2 at mid‐intertidal‐Pyura‐belts. Crowding and competition potentially affect morphological characteristics and the energy/tissue allocation along the intertidal and geographical gradient of P. stolonifera.     

Grain-size distribution patterns of suspended sediment in response to hydrodynamics on the Dafeng intertidal flat, Jiangsu, China

1Introduction The sediment dynamics of intertidal flats in-volves erosion, transport, and settling processes. A-mong these, the mechanisms of sediment transportare a key question. Progress has been made in awide range of associated areas, including sedime…     

Effects of seed predators and light level on the distribution of Avicennia marina (Forsk.) Vierh. in tropical,tidal forests

Avicennia marina has an unusual distributional pattern across the intertidal region in mangrove forests of north-eastern Australia. It is often abundant in the low intertidal and high intertidal but is very rare in mid-intertidal areas. The influences of shade intolerance and seed predators on the distribution of Avicennia were investigated. Field observations of 391 light gaps indicated that while seedlings were equally abundant in gaps versus under the neighboring forest canopy, saplings were much more abundant in gaps. Subsequent field studies showed that seedlings survived and grew best in light gaps as opposed to under the forest canopy. Further field experiments revealed that 96·0±3·4% of the post-dispersal propagules of Avicennia are consumed by seed predators, primarily grapsid crabs. Predation on propagules was less in low and high intertidal regions where conspecific adults were common and was highest in the mid intertidal where Avicennia is rarest. Predator exclusion experiments indicated that Avicennia was capable of growing in mid-intertidal areas. It is concluded that the combination of shade intolerance and extensive predation on its' propagules effectively limits the distribution of Avicennia marina across the intertidal and may account for the dominance by members of the Rhizophoraceae in the mangrove forests of northern Australia.     

广西防城港玉石滩滨螺的分布和数量初步调查

报道了广西防城港港口区旅游海区玉石滩硬相潮间带的4种滨螺,包括粗糙滨螺Littorina scabra、波纹滨螺Littorina undulate、塔结节滨螺Nodilittorina pyramidalis pyramidalis和粒结节滨螺Nodilittorina millegrana,并对其中3种的数量、分布、周年变化、个体大小等方面进行研究。其中塔结节滨螺为潮上带的优势种,而粗糙滨螺为高潮带的优势种;分布于高潮带的滨螺个体明显较潮上带的大。     

浙江苍南无居民海岛岩相潮间带生物群落多样性研究

为了解浙江苍南海域无居民海岛岩相潮间带生物群落组成与结构,于2019年3月对该海域内11个无居民海岛进行了潮间带生物调查,对采集到的样品进行鉴定,并计算了栖息密度、生物量和生物多样性指数。11个无居民海岛共鉴定出58种潮间带生物,平均栖息密度和平均生物量分别为857±205 ind/m2和2 847.83±1 032.50 g/m2,各断面的Shannon-Wiener多样性指数H′、Pielou均匀度指数J和Margalef丰富度指数D范围分别为1.07~1.61, 0.66~0.83和0.54~1.30。与大陆沿岸潮间带相比,无居民海岛生态系统独特,拥有更多的生物资源,具有重要的生态价值,需要重视并加强保护。     

A field experiment demonstrating the influence of seabird guano on intertidal primary production

Nutrient concentrations in intertidal rockpools on the shores of seabird breeding islands off the west coast of South Africa are significantly higher than concentrations in similar pools on mainland shores. This is due to the presence of terrestrial and upper intertidal guano deposits which are washed through the intertidal zone. Growth rates of intertidal macroalgae are significantly faster on the rocky shores of seabird breeding islands than on mainland rocky shores, and the extensive, permanent algal mats that develop on island shores are absent from mainland shores. The hypothesis that guano run-off enhances intertidal algal growth was tested experimentally at a site on the west coast of South Africa where no seabird colonies exist. Seawater, artificially enriched with guano, was trickled down an intertidal rocky slope during a period of two months. Algal settlement and growth on artificial surfaces were significantly enhanced by the guano treatment when compared with controls. The conclusion is that increased intertidal primary production on seabird islands, and the consequent modification of intertidal community structure, are due in part to nutrients which are introduced into the intertidal zone by run-off from the guano cap and by direct deposition of guano in the high-shore region by roosting birds.     

三都湾互花米草的遥感监测

本文尝试通过分析滩涂上外来入侵植物群落的植物学和生态学特征,就闽东宁德地区三都湾海域的互花米草生长与变化状况,探讨如何实现利用遥感数据快速监测滩涂上的外来入侵植物的方法,为生物入侵监控工作提供决策依据.研究表明以缨帽变换的方法处理LandsatETM 和TM多光谱数据所获得的土壤视面和植被视面为基础,进行分层次分类可监测滩涂上互花米草的生长与分布扩展状况.     

山东蓬莱沿海岩相潮间带贝类的垂直分布

蓬莱 ( 37°2 5’N～ 37°4 9’56”N ,1 2 0°34’4 4”E～ 1 2 1°0 9’E)位于山东半岛的北端 ,黄渤海交界处。作者通过对蓬莱沿海潮间带生物的调查 ,初步分析了岩相潮间带贝类种类及其垂直分布特点 ,依潮间带的不同区域而呈带状分布 (高潮带为滨螺群落 ,中潮带为牡蛎群落 ,低潮带为贻贝 -锈凹螺群落 )并简单分析了主要经济贝类的分布状况 ,为潮间带贝类资源合理开发与保护提供了基础资料 ,供海洋生态学、环保、水产部门参考     

Trophic ecology of Pomatoschistus microps within an intertidal bay (Roscoff,France), investigated through gut content and stable isotope analyses

The diet of Pomatoschistus microps has been studied using both gut content and stable isotope analyses. In the Roscoff Aber Bay (Brittany, France), this fish is commonly found on sandy muddy intertidal flats. Gut content analyses were also interpreted using trophic indices. Owing to the large diversity of prey consumed, these indices emphasised the opportunistic feeding behaviour of P. microps. Here, this species fed mainly on endofauna with meiofauna being of high relative importance. The main biotic components of its trophic habitat, characterized by δ¹³C and δ¹⁵N, provided evidence of a major trophic pathway based on drift Enteromorpha sp. Trophic positions estimated by both diet analyses and isotopic analyses led to similar results. In this bay, P. microps is a first‐order predator with a low degree of omnivory. Despite a preferential consumption of the amphipod Corophium arenarium, we assumed that this goby behaves as a generalist feeding on a uniform variety of endofauna taxa.     

Intertidal Invertebrate and Algal Communities on the Rocky Shores of the Bay of Morbihan, Kerguelen (South Indian Ocean)

Abstract. Both the emergent surfaces and tide pools of the rocky intertidal shores of the Bay of Morbihan, Kerguelen are depauperate in number of macroinvertebrate and macroalgal species. Diversity (H') was high and similar for macroinvertebrates in tide pools from the high to low intertidal and on the emergent surface exposed at extreme low-tide when calculated in terms of numbers of individuals. H' was lower when calculated in terms of energy and twice as high for the tide pool in the high intertidal than the lower tide-pools and the emergent surface. H' for macroalgae was 0 in the highest tide-pool and highest in the lower tide-pools. The density/species-rank curves for the macroinvertebrates and the macroalgae are logarithmic but vary in linearity. Algal biomass was 37 % of the macroinvertebrate biomass on the emergent surface at the extreme low-tide, but 106% in the highest tide-pool. Twenty-three months after denudation of the tide pools, the ratios of total densities of the macroinvertebrates (ind m^-2) to the original densities were 48 % for the pool in the high intertidal, 25 % for the middle tide-pool, and 4 % for the pool in the low intertidal. The diversity indexes for the macroinvertebrates were similar to the original ones. Recolonization at Kerguelen is slow and shows an intertidal gradient. The composition of the rocky intertidal community at Kerguelen results from the rigorous physical environment and the small number and functional types of species. In the absence of major predators on macroinvertebrates and of herbivores on macroalgae, interaction among the species present seems to be competitive in nature.     

Individual and population plasticity of the seagrass Zostera noltii along a vertical intertidal gradient

The seasonal plasticity of individual Zostera noltii architectural, reproductive and elemental content features, of plant epiphyte load and of meadow biomass–density relationships was investigated along a vertical intertidal gradient at Ria Formosa lagoon, southern Portugal. The vertical variability of the seagrass environment was evident in the sediment characteristics, which showed coarser grain size, less organic matter, lower N content and higher ammonium concentration in the low intertidal than in medium and high intertidal. A clear vertical differentiation in Z. noltii morphology was observed from longer and wider leaves, longer and wider internodes and shorter roots at low intertidal, to shorter and narrow leaves, shorter and narrower internodes and longer roots at high intertidal. The leaf size was negatively related to light availability and positively related to nutrient availability whereas the root size was negatively related to nutrient availability. The lower leaf N and P content found in low intertidal plants may reflect a dilution effect of the nutrients due to higher growth rates. Lower N content of low intertidal leaves supports previous findings that the nitrate reductase activity is lower in plants from this level. The higher epiphyte load observed in Z. noltii leaves of the low intertidal may be a consequence of the lower exposure period, but also of higher hydrodynamics that increase the availability of nutrients. No evidence of the influence of the intertidal level on the flowering shoot density was found. The cyclic temporal pattern of the biomass–density relationship was much wider at low and medium intertidal than at high intertidal. At low intertidal, the decline in shoot density during fall and winter was coincident with a biomass decrease and its increase in spring and summer coincided with the biomass increase. In medium and high intertidal, the biomass and density seasonal variations were decoupled. As a result, only at low intertidal there was a significant positive relationship between biomass and density. This suggests that Z. noltii population structure along the intertidal is regulated by different factors. Light is probably the most important factor regulating the population structure in the low intertidal, whereas desiccation is probably the main factor regulating the populations in upper intertidal. Zostera noltii showed a considerable plasticity at a physiological-, plant- and population-level along the intertidal zone, indicative of the species acclimation to the steep environmental gradient of this particular ecosystem.     

The effects of semi-lunar spring and neap tidal change on nitrification, denitrification and N2O vertical distribution in the intertidal sediments of the Yangtze estuary, China

To explore the influences of semi-lunar spring and neap tidal changes on nitrogen cycling in intertidal sediments, a comparative study among waterlogged, desiccated and reflooded systems was carried out in August 2005 and February 2006 by analyzing nitrification, denitrification and N₂O depth profiles in the intertidal flats of the Yangtze estuary. Laboratory experiments showed that alternating emersion and inundation resulted in the significant changes in nitrification and denitrification rates in the intertidal sediment systems. Due to the desiccation-related effects, lowest nitrification and denitrification rates were observed in the desiccated sediment cores. Highest nitrification and denitrification rates were however detected in the waterlogged and reflooded systems, respectively. It is hypothesized that the highest nitrification rates in the waterlogged sediments were mainly attributed to higher nitrifier numbers and NH₄⁺ being more available, whereas the availability of NO₃⁻ might dominate denitrification in the reflooded sediments. In addition, the highest N₂O concentrations were detected in the reflooded sediment cores, and the lowest found in the dried sediment cores. It was also shown that N₂O in the intertidal sediments was mainly from nitrification under the desiccated condition. In contrast, N₂O in the intertidal sediments was produced mainly via denitrification under the waterlogged and reflooded conditions. It is therefore concluded that the semi-lunar tidal cycle has a significant influence on nitrification, denitrification and N₂O production in the intertidal sediment systems.