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1.
长山列岛南部三岛岩相潮间带群落多样性格局   总被引:8,自引:0,他引:8  
对长山列岛南部南长山、北长山和大黑山岛屿岩相潮间带群落种类组成的调查表明,3岛屿岩礁潮间带的群落结构差异不大,表现在决定群落结构和外貌的前5位优势种群及其优势度序列基本相同;而砾石潮间带的群落结构存在一定差异,表现在北长山群落中优势种群及其优势度序列显著地区别于南长山和大黑山,但后二者趋同-3岛屿岩礁潮间带的景观和群落外貌与结构由东方小藤壶(Chthamalus chal-lengeri)、牡蛎(Ostrea spp.)、大型藻类和短滨螺(Littorina breuicula)控制,砾石潮间带则由东方小藤壶、大型藻类和平背蜞(Gaetice depressus)决定.群落多样性由物种丰富度(R)、均匀度(J)和多样性(HB、Hlv、DR、DIv)衡量,3岛屿岩礁潮间带群落的各种多样性指数呈现一致性,群落多样性以北长山最高,大黑山最低;而砾石潮间带群落的各种多样性指数存在一定差异,南长山高于北长山和大黑山,北长山潮间带群落中物种分布的均匀度最高,南长山和大黑山趋同.比较3岛屿两种基质潮间带的群落多样性发现,砾石潮间带高于岩礁潮间带。  相似文献   

2.
The North Inlet marsh — estuarine ecosystem (located at South Carolina, USA) is described via three sub-models: intertidal, benthic-subtidal and water column. The principal storage compartments and fluxes of energy are defined for each submodel. A detailed example of the intertidal oyster subsystem of the intertidal submodel is described. The biological components of the intertidal oyster subsystem of the intertidal submodel is described. The biological components of the oyster community are shown to be stable and a linear systems model of the oyster community is developed. A 1% sensitivity analysis of the intertidal oyster model affords some order in which aspects of the oyster community should be studied.  相似文献   

3.
厦门潮间带春季鸟类群落的生态分析   总被引:19,自引:1,他引:18  
厦门岛位于台湾海峡西部,北纬24°20′,东经118°4′左右,属典型亚热带海洋性季风气候,年平均气温208℃,年降雨量约1100mm。厦门岛三面隔海与大陆相邻,一面潮向外海;潮汐是规则的半日潮,同时具有日潮不等的特征,潮间带每日两次暴露于空气中[5]。厦门鸟类区系及生态分布情况,曾有几位国外学者做过零星考察[2,7],但未有系统专门报道。关于潮间带鸟类群落研究的国内报道也尚不多见,仅有陆健健等对东海北部的行鸟鹬群落做过研究[4]。我们于3~5月间对厦门潮间带鸟类进行了调查,目的在于初步了解厦门不同地区潮间带的鸟类种类组成和数量状况,探…  相似文献   

4.
基于长江口3个区域潮间带(崇明东滩、南汇边滩和嵊山岛)监测数据,对长江口区域潮间带底栖生物生态现状及变化趋势进行评价。结果表明,2019年长江口海域泥相和岩相潮间带共鉴定大型底栖生物9门57种,软体动物、甲壳类和多毛类构成主要类群。崇明东滩、南汇边滩两个泥相潮间带底栖生物平均栖息密度分别为96.4个/m~2和160.4个/m~2,平均生物量分别为68.42 g/m~2和45.71 g/m~2;嵊山岛岩相潮间带平均栖息密度和生物量分别为488.9个/m~2和763.72 g/m~2。各断面多样性、丰富度和均匀度指数分别位于1.36—3.24、0.75—2.88和0.48—0.77,泥相潮间带低潮区生物多样性优于中潮区和高潮区,岩相潮间带中潮区生物多样性最好。聚类分析可见长江口海域潮间带底栖生物分为泥相和岩相2个大组群,物种分布存在明显的分潮区现象,高潮区站位成群或与个别中潮区站位成群,低潮区站位成群或与个别中潮区站位成群,表明底质类型和潮汐是影响潮间带大型底栖生物群落结构的主要因子。近30年来,崇明东滩和南汇边滩底栖生物种类数存在一定波动,嵊山后陀湾断面生物种类数明显下降;3个区域潮间带...  相似文献   

5.
A quantitative assessment of the effects of intertidal elevation on rockpool ichthyofaunas was investigated at four locations in southeastern New South Wales, Australia. Rockpools supported high diversity and abundance of fishes mainly comprising the families Clinidae, Blennidae, Tripterygiidae, Gobiidae, Gobiesocidae and Girellidae, which are mostly permanent residents. Mean numbers of species and individuals did not differ among low, medium and high rockpools. In contrast, species composition differed among intertidal rockpool heights with pools mainly being dominated by transient and opportunist species in lower intertidal, opportunists and permanent residents in the mid intertidal, and mainly permanent residents in the high intertidal. Distribution patterns appeared to be related to the morphological and/or physiological adaptations of species to the increasingly harsh and variable environmental conditions with increasing intertidal elevation. Residential status of each species may be used as a proxy for intertidal vertical distribution although some exceptions exist, namely Girella elevata, which may posses behavioural adaptations to cope with harsh environmental conditions.  相似文献   

6.
The intertidal and subtidal soft bottom macro- and meiofauna of a glacier fjord on Spitsbergen was studied after complete ice melt in June 2003. The abundances of the benthic fauna were within the range reported from estuaries and similar intertidal areas of boreal regions. The high proportion of juveniles in the eulittoral zone indicated larval recruitment from subtidal areas. The macrobenthic fauna can be divided into an intertidal and a subtidal community, both being numerically dominated by annelids. Deposit feeders were numerically predominant in intertidal sites, whereas suspension feeders were most abundant in the subtidal area. Among the meiofauna, only the benthic copepods were identified to species, revealing ecological adaptations typical for intertidal species elsewhere.  相似文献   

7.
Abstract We report the composition of terrestrial, intertidal and shallow sublittoral faunal communities at sites around Rothera Research Station, Adelaide Island, Antarctic Peninsula. We examined primary hypotheses that the marine environment will have considerably higher species richness, biomass and abundance than the terrestrial, and that both will be greater than that found in the intertidal. We also compared ages and sizes of individuals of selected marine taxa between intertidal and subtidal zones to test the hypothesis that animals in a more stressed environment (intertidal) would be smaller and shorter lived. Species richness of intertidal and subtidal communities was found to be similar, with considerable overlap in composition. However, terrestrial communities showed no overlap with the intertidal, differing from previous reports, particularly from further north on the Antarctic Peninsula and Scotia Arc. Faunal biomass was variable but highest in the sublittoral. While terrestrial communities were depauperate with low biomass they displayed the highest overall abundance, with a mean of over 3 × 105 individuals per square metre. No significant differences in ages of intertidal and subtidal individuals of the same species were found, with bryozoan colonies of up to 4 years of age being present in the intertidal. In contrast with expectation and the limited existing literature we conclude that, while the Antarctic intertidal zone is clearly a suboptimal and highly stressful habitat, its faunal community can be well established and relatively diverse, and is not limited to short‐term opportunists or waifs and strays.  相似文献   

8.
This paper presents a comparative analysis of territoriality in three intertidal (Lipophrys pholis, Coryphoblennius galerita, Salaria pavo) and two subtidal (Tripterygion delaisi, Parablennius pilicornis) blennioid fishes. Focal-animal observations of males guarding eggs showed that: (i) intertidal species had smaller territories that were less frequently patrolled; (ii) in subtidal species feeding was limited to the territory, while in intertidal fishes a substantial proportion of the feeding acts occurred outside the defended area; (iii) intertidal species spent less time out of the nest and showed a lower level of locomotory activity; (iv) subtidal species were subjected to a higher number of territorial intrusions with more species intruding their territory, some of them potential egg predators; (v) subtidal species performed several water column displays that played a significant role in courtship, while in intertidal fishes these displays are almost absent. Signalling without the presence of a female was almost absent in intertidal species. It is argued that intertidal fishes minimize the time spent out of the nest and the loss of contact with the substrate, features that may be of high survival value in conditions of strong turbulence. Although intertidal species have a reduced time available for feeding, this may be compensated by lower levels of locomotory activity, territorial defense and risk of egg predation. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

9.
A historical review. By the end of the 20th century, the composition of intertidal biota has been studied in all Russian Far Eastern seas; the specific features of vertical zonation in intertidal communities have been revealed; the major belt-forming communities of flora and fauna have been described and studied in the quantitative aspect; the existence of bionomic types in the intertidal zone, similar to those in the coastal area of the Barents Sea, has been corroborated; and some regularities have been retraced in the geographical zonation of different types of marine intertidal zone. The progress of the scientific school of Academician Oleg G. Kusakin has been particularly emphasized in the investigations of intertidal biota, communities and taxocenoses.  相似文献   

10.
The red alga Mazzaella laminarioides is an economically important species with an extended latitudinal distribution along the Chilean coast. Its populations form mid-intertidal stands, several meters wide, and therefore are differentially exposed to environmental variables that result in temporal and spatial variability in productivity. We evaluated the effect of latitude and intertidal height on productivity by in situ measurement of photosynthetic performance. Daily and seasonal variations of O2-evolution rate and maximal quantum yield (F v/F m) were determined in plants from the upper and lower intertidal zone at two localities 1500,km apart. Results suggest that plant responses were mainly affected by irradiation, temperature and desiccation. At local level, upper intertidal plants showed a reduced photosynthetic rate and quantum efficiency as compared to those displayed by plants from the lower intertidal, indicating their higher level of excitation energy acclimation. Stronger acclimation differences between upper and lower intertidal plants were observed in spring and summer. Differences in photosynthetic parameters between reproductive phases were recorded in autumn and winter, regardless of the position of the individuals in the intertidal zone. The effects of tidal elevation on seasonal patterns of photosynthesis were also influenced by latitude. Seasonal variation in photosynthetic efficiency was observed in plants from the northern population at both intertidal elevations, but only at the upper intertidal level in the southern population. This study shows that production variability in M. laminarioides results from differences in the intensity of environmental factors observed seasonally at local (intertidal) and latitudinal scales.  相似文献   

11.
The Pacific sand lance (Ammodytes hexapterus) is an ecologically important prey species for many vertebrate marine predators in the Pacific Northwest. In this study, we examined the use of intertidal habitat by young of the year (YOY) sand lance in Barkley Sound, British Columbia. We selected 14 of the original 29 independent environmental variables for modelling based on univariate analysis for variable selection. These were then used to model sand lance presence-absence using a classification tree approach. Based on our models we found that sand lance avoided mud and intertidal eelgrass. For sites that had very little mud and no intertidal eelgrass, sand lance preferred sediment size mean ≥1,918 μm or sites with sediment size mean ≤1,918 μm but with relatively well sorted sediment (sorting values ≤2.56 SDs, used as a heterogeneity index of the substrate grain size). Adjacent subtidal characteristics were not found to be important at this scale of study. This suggests intertidal substrate characteristics and presence-absence of intertidal eelgrass are the main influences on occurrence of YOY in the intertidal. Our results support the hypothesis that sand lance are associated with particular sediment types, however intertidal sediment types used by sand lance in our study differ from known preferences of sand lance for subtidal sediment types. This difference may be due to unique habitat constraints for intertidal versus subtidal regions. Although it is unknown if the results of this study are widely applicable, the results begin to identify intertidal habitat features that are important for Pacific sand lance.  相似文献   

12.
A. D. Naumov 《Hydrobiologia》2013,706(1):159-173
The effect on bottom organisms of periodic freezing of the upper layer of intertidal sediments during abnormal cold winters has been studied for a long time in seas of a moderate climatic zone. However, the effect of ice cover every year on intertidal communities in polar seas is still poorly investigated. Seasonal and long-term variation in the structure of intertidal soft-bottom communities in two small bights in the White Sea with annual ice cover was studied for over two decades. Sampling was carried out four times a year, in the hydrological spring, summer, autumn, and winter. It was found that bottom macrobenthic communities at upper and lower horizons of the intertidal distinctly differed in the studied sites. Periodic changes caused by the effect of abnormal ice conditions, including the partial removal by ice of sediment with in situ organisms, were discovered. Recovery of communities after disturbance normally took less than half a year. Communities at the lower and upper horizons of the intertidal zone were more stable than intermediate communities, which led to periodic shifts of the biological border between lower and upper intertidal assemblages.  相似文献   

13.
Marine intertidal sediments fluctuate in redox conditions and nutrient availability, and they are also known as an important sink of nitrogen mainly through denitrification, yet how denitrifying bacteria adapt to this dynamic habitat remains largely untapped. Here, we investigated novel intertidal benthic ecotypes of the model pelagic marine bacterium Ruegeria pomeroyi DSS-3 with a population genomic approach. While differing by only 1.3% at the 16S rRNA gene level, members of the intertidal benthic ecotypes are complete denitrifiers whereas the pelagic ecotype representative (DSS-3) is a partial denitrifier lacking a nitrate reductase. The intertidal benthic ecotypes are further differentiated by using non-homologous nitrate reductases and a different set of genes that allow alleviating oxidative stress and acquiring organic substrates. In the presence of nitrate, the two ecotypes showed contrasting growth patterns under initial oxygen concentrations at 1 vol% versus 7 vol% and supplemented with different carbon sources abundant in intertidal sediments. Collectively, this combination of evidence indicates that there are cryptic niches in coastal intertidal sediments that support divergent evolution of denitrifying bacteria. This knowledge will in turn help understand how these benthic environments operate to effectively remove nitrogen.  相似文献   

14.
In this study we used pinfish (Lagodon rhomboides) in field experiments to examine linkages between intertidal saltmarsh and adjacent subtidal habitats. Pinfish are more than twice as abundant in intertidal marshes adjacent to seagrass beds than in those adjacent to the unvegetated subtidal bottom. Movement of pinfish between the marsh edge and the adjacent subtidal habitat was greater for fish captured in areas with both intertidal and subtidal vegetation than in those with intertidal vegetation and adjacent unvegetated mudflats. This movement provides an important link between habitats, allowing transfer of marsh-derived secondary production to subtidal seagrass beds and vice versa. Pinfish held in enclosures with both intertidal and subtidal vegetation were, on average, approximately 90% heavier than fish held in enclosures with intertidal vegetation and unvegetated subtidal bottom. Because saltmarshes and seagrass beds contribute to the production of living marine resources, active measures are being taken to preserve and restore these habitats. The results from this study have direct application to decisions concerning site selection and optimal spatial proximity of saltmarsh and seagrass habitats in the planning of restoration and mitigation projects. To maximize secondary production and utilization of intertidal marshes, managers may opt to restore and/or preserve marshes adjacent to subtidal seagrass beds. Received: 31 May 1996 / Accepted: 23 October 1996  相似文献   

15.
Summary Community organization was studied by experiment and observation from October 1972–October 1974 in the marine epifaunal assemblages at each end of Barnegat Inlet, New Jersey. The rock jetty at the wave-exposed eastern end of the inlet possesses an intertidal community with the following attributes: (1) a high intertidal zone dominated by the barnacle, Balanus balanoides, but also occupied by the blue mussel, Mytilus edulis, in rock crevices, (2) a mid and low intertidal zone with usually <10% free space and extreme numerical dominance by Mytilus edulis (usually >85% cover) during summer and fall, and (3) almost no intertidal predators or herbivores. The predatory seastar, Asterias forbesi, is abundant subtidally. Controlled removal experiments indicate that in the mid and low intertidal underlying barnacles perish as a consequence of the establishmentof extensive secondary cover by Mytilus, probably because Mytilus outcompetes Balanus through suffocation or starvation. Mytilus transplants demonstrate that the mussels do not survive outside of crevices in the high intertidal, which thus may represent for Balanus a refuge from competition by Mytilus.The pilings on docks at the protected western end of Barnegat Inlet possess an intertidal epifaunal community with the following characteristics: (1) a high intertidal zone that includes Balanus balanoides, a second barnacle, Balanus eburneus, and an herbivorous gastropod, Littorina littorea, (2) a mid and low intertidal zone with usually >40% free space in the summer and fall and the remaining area covered by several abundant species with no extreme dominant, and (3) abundant predators, chiefly the oyster drill, Urosalpinx cinerea, the blue crab, Callinectes sapidus, and a mud crab, Neopanope texana sayi. Asterias forbesi, while abundant subtidally, is also occasionally present on intertidal surfaces. Controlled exclusion of predators by caging several replicate pilings at the western end of the inlet reveals that predation prevents monopolization of mid and low intertidal space by the apparent competitive dominant, Mytilus. Predation appears to be a direct cause of the relatively great temporal and spatial heterogeneity in the mid and low intertidal of these pilings.Thus, although the Barnegat Inlet intertidal system appears to follow closely the patterns of community organization described for several other rocky intertidal coastlines, this organizational pattern is noteworthy because it is repeated here in a far more seasonal environment and with a new cast of interacting competitors and predators. That crabs play an important role as predators is novel for North America, but only perhaps because all previous North American studies have ignored the rocky intertidal zones of quiet, estuarine waters where in Europe predatory crabs are known to be extremely significant.This paper is dedicated to the memory of Robert H. MacArthur  相似文献   

16.
The barnacle Balanus glandula was introduced in Argentina in the 1970s, and today it dominates the high intertidal level in most Argentinean rocky shores. The aim of this work was to evaluate the effect of the type of substrata and intertidal height on a population of Balanus glandula by conducting field surveys and one-year field experiments in which we combined different substrata (hardness: hard and soft, and texture: smooth and rough) at two intertidal heights (mid and high). In natural populations, the highest density of adults and recruits occurred on soft-rough substratum and in the high intertidal. The different textures were important only on the soft substrata and high intertidal, and the density of barnacles of the soft-rough substrata was higher than soft and smooth ones. The most suitable experimental substratum was the soft-rough of the high intertidal, which had the highest recruitment, survival and final density of barnacles at the end of the experiment. In contrast, the hard and smooth of the high and middle intertidal were the least suitable in all cases. Although the recruitment of B. glandula occurred throughout the year, it was higher in the high intertidal, and it showed a recruitment peak in the winter and a second in the summer. While most studies on this barnacle investigated the effects of granite or other volcanic hard substrata, our study also focused on soft substrata. The effects of soft substrata are particularly important because soft sedimentary rocks characterise the southern Atlantic coast of South America and the presence of soft rocks appears to optimize the success of Balanus glandula.  相似文献   

17.
上海滩涂植被资源遥感分析   总被引:18,自引:3,他引:15  
黄华梅  张利权  高占国 《生态学报》2005,25(10):2686-2693
利用2003年8月2日L andsat5-TM多光谱遥感影像,运用遥感处理软件ERDA S Im ag ine 8.6,经几何校正分幅裁剪等图像预处理后,采用监督分类和目视解译相结合对上海市滩涂植被进行解译分析。结合全球定位系统(GPS)样点定位,对分类结果进行全面的野外核实和修正,同时利用地理信息系统(G IS)对解译结果进行数据合成,统计出滩涂各类植被的分布区域及面积等数据。实际调查及其分析统计显示,上海滩涂植物群落总面积为21302.1hm2,主要植被组成为芦苇、海三棱草及互花米草三大群落,滩涂植物群落具有明显的高程梯度分布规律。大尺度的上海市滩涂植被的空间分布现状及其数量调查为上海市滩涂资源的合理规划、生物多样性保护和可持续开发利用提供科学依据。  相似文献   

18.
The structure of rocky intertidal communities may be influenced by large-scale patterns of productivity. In this study we examine the in situ rates of production by intertidal epilithic microalgae (chlorophyll a production per unit area per month), intertidal nutrient concentrations (nitrates, nitrites, phosphates and silicates), and standing stocks of different functional-form groups of macroalgae around the South African coast, and their relationships to consumer biomass. Clear gradients of in situ intertidal primary production and nutrient concentrations were recorded around the South African coast, values being highest on the west coast, intermediate on the south and lowest on the east coast. Primary production by intertidal epilithic microalgae was correlated with nutrient availability and could also be related to nearshore phytoplankton production. The dominance patterns of different functional forms of macroalgae changed around the coast, with foliose algae prevalent on the west coast and coralline algae on the east coast. However, overall macroalgal standing stocks did not reflect the productivity gradient, being equally high on the east and west coasts, and low in the south. Positive relationships existed between the average biomass of intertidal intertebrate consumers (grazers and filter-feeders) and intertidal productivity, although only the grazers were directly connected to in situ production by epilithic intertidal microalgae. The maximum body size of a widely distributed limpet, Patella granularis, was also positively correlated with level of in situ primary production. The maximal values of biomass attained by intertidal filter-feeders were not related to intertidal primary production, and were relatively constant around the coast. At a local scale, filter-feeder biomass is known to be strongly influenced by wave action. This implies that the local-scale water movements over-ride any effects that large-scale gradients of primary production may have on filter-feeders. The large-scale gradient in intertidal productivity around the coast is thus strongly linked with grazer biomass and individual body size, but any effect it has on filter-feeder biomass seems subsidiary to the local effects of wave action.  相似文献   

19.
Reciprocal transplant experiments were used to study the effects of tidal inundation and light level on growth and survival of four species of mangroves in Australia: Avicennia marina (Forsk.) Vierh., Bruguiera gymnorrhiza (L.) Lam., Ceriops tagal C.T. White, and Rhizophora stylosa Griff. Seedlings were planted in the high or low intertidal and in light gaps or under the shade of a closed canopy. Survival and growth of the seedlings were monitored for 30–36 months. Significant differences in survival were found among species, between intertidal zones and due to light level. Averaged across intertidal zones and light level, survival was greatest for Rhizophora and decreased in the order Ceriops, Avicennia, and Bruguiera. For all species survival was greater (P ⩽ 0.001) in the high than in the low intertidal treatment, regardless of light level. Within the high intertidal all species survived better in light gaps than under the canopy. Relative growth of Rhizophora stylosa, Avicennia marina, and Ceriops tagal were greater in the high versus low intertidal and in gaps versus under the canopy. For Bruguiera gymnorrhiza growth was not significantly different between gap and canopy or high and low intertidal. Although Avicennia marina, Bruguiera gymnorrhiza, and Rhizophora stylosa survived and/or grew best in the high intertidal they reach maximum abundance in the low intertidal. Ceriops tagal, however, performed best in the region where it is most abundant, yet even there, it was out-performed by the former three species. These results indicate that the species zonation patterns often observed across the intertidal cannot be explained by physiological adaptation alone. Factors such as propagule dispersal, competition and predation on propagules may also be important.  相似文献   

20.
Marine intertidal organisms are subjected to a variety of abiotic stresses, including aerial exposure and wide ranges of temperature. Intertidal species generally have higher thermal tolerance limits than do subtidal species, and tropical species have higher thermal tolerance limits than do temperate species. The adaptive significance of upper thermal tolerance limits of intertidal organisms, however, has not been examined within a comparative context. Here, we present a comparative analysis of the adaptive significance of upper thermal tolerance limits in 20 congeneric species of porcelain crabs, genus Petrolisthes, from intertidal and subtidal habitats throughout the eastern Pacific. Upper thermal tolerance limits are positively correlated with surface water temperatures and with maximal microhabitat temperatures. Analysis of phylogenetically independent contrasts (from a phylogenetic tree on the basis of the 16s rDNA gene sequence) suggests that upper thermal tolerance limits have evolved in response to maximal microhabitat temperatures. Upper thermal tolerance limits increased during thermal acclimation at elevated temperatures, the amount of increase being greater for subtidal than for intertidal species. This result suggests that the upper thermal tolerance limits of some intertidal species may be near current habitat temperature maxima, and global warming thus may affect the distribution limits of intertidal species to a greater extent than for subtidal species.  相似文献   

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