Impact of Human Activities on Depositional Process of Tidal Flat in Quanzhou Bay of China   总被引：2，自引：0，他引：2  

WANG Aijun 《中国地理科学(英文版)》2007,17(3):265-269

As a very important component of a coastal system,tidal flats come to be a focus of the studies on land-ocean interaction in the coastal zone because those areas are subjected to intense human activities and are highly sensitive to the global change.The Quanzhou Bay,located along the middle part of Fujian coast of China,covers about 136.4km2,and the area of coastal wetland in the entire bay from intertidal to subtidal with 6m of water depth accounts for 96% of the total area.Seven short cores were collected and divided in situ with the interval of 5cm on the coastal wetlands of Quanzhou Bay on April 19,2006.The sediment samples were scattered and the grain sizes were measured by using Mastersizer 2000.Human beings' activities on tidal flat have disturbed the vertical distribution of sediments in stratigraphic sequence and accelerated the sedimentation rates.Grain size analysis results show that the grain size diameters increase and sediment becomes worse sorted towards the sea under the strong human disturbance;Spartina alterniflora can play a role of trapping the fine sediment;but near the bank,the sediment becomes coarse and there are two peak values on frequency curve influenced by the sandpile.The trough formed by human activities along the coastline changes the transport path of water and suspended sediment.The sediments are transported through the trough and deposit in it during the flood;the ebb flow is retarded by the flow output through the adjacent trough,and the deposited sediment can not be re-suspended;then,the sedimentation rate increases.In situ observation show that the sedimentation rate is about 8-10cm/yr.  相似文献   

Altering intertidal sediment topography: effects on biodiversity and ecosystem functioning     

Diane Jones  & Chris L. J. Frid 《Marine Ecology》2009,30(S1):83-96

Sedimentary marine systems are often highly productive and perform important nutrient regeneration functions as they efficiently decompose organic material. In recent years the role of habitat effects and of species composition in ecosystem functioning has become of interest. Estuarine environments are frequently subject to considerable anthropogenic pressures whilst supporting a variety of habitats ranging from well sorted soft muds through biogenically stable sediments to highly mobile coarse sands. There is therefore considerable spatial complexity in habitat type and faunal composition. This study set out to observe the effects of altering the topographical habitat features of an estuarine mudflat on a range of porewater nutrient concentrations (NH₄⁺, NO₃⁻, NO₂⁻, PO₄³⁻ and SiO) collected from four depths (3, 5, 9, and 12 cm) and on faunal composition. Two treatments (Shelled Nets and Net Controls) were used to alter the topography from simple mud to a mussel shell crumble and were compared to un-manipulated Control areas. Sediment granulometry and organic matter content analyses alongside biological traits analysis of the fauna were also conducted.
Differences were observed in porewater nutrient concentrations between the Control and both netted treatments at 5 cm depth only; the species diversity and abundance were also different in the netted treatments compared to the Controls, although no difference between the two manipulated treatments were observed. The changes in faunal composition were attributed solely to the altered topography and the observed nutrient changes were attributed to the faunal alteration rather than the topographical manipulation.  相似文献   

杭州湾上海石化沿岸潮间带生态环境分析   总被引：1，自引：0，他引：1  

张进龙 《海洋湖沼通报》2008,(1):74-79

通过对1993～2002年杭州湾上海石化沿岸潮间带底栖动物群落结构的分析,得出上海石化处理达标后排放的工业废水对此段潮间带生态环境影响的范围和程度。自2002年到现在为止,本潮间带的底栖动物群落结构呈现一种适应性广、耐污染的结构组成.其生物多样性指数值在2.00～3.50之间。  相似文献   

Mangrove expansion and rainfall patterns in Moreton Bay, Southeast Queensland, Australia     

L. Eslami-Andargoli  Per Dale  N. Sipe  J. Chaseling 《Estuarine, Coastal and Shelf Science》2009,85(2):292-298

Changes in rainfall pattern have been suggested as a mechanism for the landward incursion of mangrove into salt marsh. The aim of the research was to assess the relationship between rainfall patterns and the spatial distribution of mangrove forests at study sites in Moreton Bay, Southeast Queensland, Australia, over a 32-year period from 1972 to 2004. To identify periods of relatively consistent rainfall patterns points at which rainfall patterns changed (change-points) were identified using the non-parametric Pettitt–Mann–Whitney-Statistic and the cumulative sum technique. The change-points were then used to define the temporal periods over which changes to mangrove area were assessed. Both mangrove and salt marsh area were measured by digitizing aerial photographs acquired in 1972, 1990 (the year with the most significant change-point), and 2004. The rates of change in mangrove area pre-1990 (a wetter period) and post-1990 (a drier period) were estimated. A significant positive relationship was demonstrated between rainfall variables and landward mangrove expansion, but not for seaward expansion. We concluded that rainfall variability is one of the principal factors influencing the rate of upslope encroachment of mangrove. However, the rate of expansion may vary from site to site due to site-specific geomorphological and hydrological characteristics and the level of disturbance in the catchment.  相似文献   

苏北潮滩的近期变化分析   总被引：2，自引：0，他引：2       下载免费PDF全文

宋召军  黄海军  王珍岩  严立文  樊建勇 《海洋科学》2008,32(6):25-29

利用1999～2000年条子泥岸滩剖面实测数据和1982～1983年东沙沙滩剖面资料，分析了条子泥岸滩和东沙沙滩剖面的冲淤变化。结果表明，条子泥陆侧岸滩剖面的季节性变化特点是夏季侵蚀，冬季淤积；东沙沙脊年际变化特点为两侧边缘以侵蚀为主，而沙脊中央则以淤积为主。造成条子泥岸滩剖面季节性差异的主要原因是其周围海域中高浓度悬沙的秋、冬季落淤大于夏季所致。东沙沙脊东西两侧强烈的潮流和波浪作用使沙脊的两侧遭受较为明显的侵蚀。  相似文献   

Inter-season and interannual variations in fish and macrocrustacean community structure on a eastern English Channel sandy beach: Influence of environmental factors     

Jonathan Selleslagh  Rachid Amara 《Estuarine, Coastal and Shelf Science》2008,77(4):721-730

The intertidal zone of an exposed sandy beach on the French coast of the English Channel was sampled with a 1.5 m beam-trawl over five years (2000 and 2003–2006) at weekly intervals. The fish and macrocrustacean catches were analysed to determine the inter-season and interannual variation in community structure and relate these variations to changes in the major environmental variables. Only six species (plaice Pleuronectes platessa, common goby Pomatoschistus microps, sprat Sprattus sprattus, sand eel Ammodytes tobianus, brown shrimp Crangon crangon and shore crab Carcinus maenas) from the 27 species captured can be considered as dominant species of the intertidal zone, and they accounted for >90% of total numbers. Most individuals caught were young-of-the-year or juvenile. Analysis of similarities (ANOSIM) and similarities percentage (SIMPER) indicated that inter-season variability of community structure (mean average similarity = 47%) was more pronounced than interannual variability (mean average similarity = 65%). Canonical correspondence analysis (CCA) indicates that a substantial component (32.2%) of the measured inter-season variation in community structure can be explained by environmental factors (mainly water temperature). The main inter-season changes in the abundance and community structure were due to the variation of the six key species and reflect the different times of their recruitment. During the five years of the study, the structure of the fish and macrocrustacean spring community persisted from year to year, with the dominant species reappearing consistently even though their abundances fluctuated from year to year. This interannual variation probably reflects variable recruitment success influenced by physico-chemical conditions. In spite of the considerable interannual variation (40 times) in the spring bloom of the prymnesiophyte alga Phaeocystis globosa we found no effect of this bloom on either fish and macrocrustacean species densities or diversity index.  相似文献   

我国海洋底栖猛水蚤目两个新记录种     

马林  李新正 《海洋与湖沼》2015,46(6):1321-1325

通过对2008 年5 月在江苏平岛潮间带采集的砂质沉积物进行离心提取, 经形态分类学方法 鉴定发现底栖猛水蚤目两个新记录种, 濑户叶足猛水蚤Phyllopodopsyllus setouchiensis Kitazima, 1981 和扎哈美猛水蚤 Ameira zahaae Karanovic & Cho, 2012, 分别隶属于矩头猛水蚤科 Tetragonicipitidae Lang, 1948 和美猛水蚤科 Ameiridae Boeck, 1865.其中, 濑户叶足猛水蚤目前仅在 砂质潮间带环境中发现。扎哈美猛水蚤与韩国海域发现的种形态基本一致。  相似文献   

天津鲤鱼门滩涂经济贝类资源变化及原因探讨   总被引：1，自引：1，他引：0  

李永仁  梁健  郭永军  邢克智 《海洋科学》2015,39(11):68-73

为探讨天津汉沽鲤鱼门潮间带经济贝类资源的变化特征,2012~2014年作者对该滩涂经济贝类开展资源调查,并与2008年的调查结果进行对比分析。结果表明:2012~2014年经济贝类种数分别为9种、10种、10种,高于2008年的7种;鲤鱼门滩涂经济贝类主要分布于中潮区,2012~2014年中潮区经济贝类资源量分别为1 082.8、1 183.9和1 339.8g/m2,高于2008年的293.5 g/m2;2012~2014年优势种为菲律宾蛤(Ruditapes philippinarum)仔,优势度90%以上,2008年优势种为四角蛤蜊(Mactra veneriformis);近年来菲律宾蛤仔大量出现,与邻近海域的大规模增殖放流活动密切相关。  相似文献   

Diet and food preference of intertidal Astrostole scabra (Asteroidea: Forcipulata)     

John C. Town 《新西兰海洋与淡水研究杂志》2013,47(4):427-435

Dietary composition in Astrostole scabra was ascertained by regular sampling at four geographically separated locations on the Kaikoura coast between January 1976 and January 1977. A. scabra is a food generalist and scavenger with a diet composed mainly of molluscs and crustaceans belonging to more than 60 genera. The diet was dominated numerically by chitons and trochid molluscs. Several site‐specific differences in dietary composition were apparent. Only Ischnochiton maorianus was a numerically important prey species at all study sites. Dietary diversity and evenness were more or less constant and comparable both seasonally and geographically. The proportion of intertidal seastars feeding fluctuated during the study from a peak of 42% in January to 23.7% in June 1976. Prey species were consumed in proportions independent of their abundance. In the laboratory, A. scabra, free of ingestive conditioning, discriminated between different prey species and preferentially consumed I. maorianus. There were strong prey preferences at the specific, but not at the familial, level.  相似文献   

Genetic variation and population structure in the New Zealand snapper   总被引：1，自引：1，他引：0  

P. J. Smith  R. I. C. C. Francis  L. J. Paul 《新西兰海洋与淡水研究杂志》2013,47(4):343-350

Fifteen proteins encoded by 23 gene loci were electrophoretically surveyed in two samples of snapper Chrysophrys auratus (Forster) from Wellington Harbour and the Hauraki Gulf. Between 17% and 26% of the loci examined were found to be polymorphic and the proportion of heterozygous loci per individual was 7.9% to 8.4%. Using Rogers’ genetic distance coefficient an overall similarity of 0.98 was calculated between the two samples.

Three polymorphic loci Est‐4, Gpi‐1, and Idh were examined in an additional 10 samples from around New Zealand. Two genetically distinct stocks were apparent: one along the west coast, the other along the east coast of the North Island. There was an indication of stock mixing at Ninety Mile Beach and in the Bay of Plenty and East Cape. The distribution of alleles at the Est‐4 locus revealed a third stock in Hawke Bay that is genetically more similar to the west coast than the east coast stock. Hydrological conditions in Hawke Bay are more similar to those of the west coast than to those of the north east coast of the North Island. Thus it is possible that Est‐4 alleles are selectively maintained in response to an environmental factor.  相似文献