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21.
Abstract. Nematode assemblages along a Mediterranean depth transect (160–1220 m) and vertically in the sediment were investigated. The station at the edge of the continental shelf (160 m) was distinctly different from those situated on the continental slope (280–1220 m). On the slope, nematode communities in the upper centimetre differed significantly from communities in the deeper sediment layers, which were dominated by fewer and larger species. Vertical segregation could be a factor explaining the coexistence of several species belonging to the genus Sabatieria , with larger species penetrating deeper into the sediment. Clear differences in buccal morphology suggest food resource partitioning as the dominant factor promoting coexistence of several species belonging to the other dominant genus, Acantholaimus . 相似文献
22.
Dispersal of Benthic Meiofauna by Wave and Current Action in Bogue Sound, North Carolina, USA 总被引：3，自引：0，他引：3
Abstract. Results from sediment trap experiments in Bogue Sound, North Carolina, indicate that meiofauna from a wide variety of taxa and benthic habitats are regularly suspended in the subtidal water column. Interstitial species are estimated to account for 10–30 % of the suspended meiofauna. Measurements of suspended nematode concentrations, when compared with wind and current velocity records, suggest that in Bogue Sound, shoaling and breaking waves are more important than tidal currents in controlling meiofauna erosion and deposition. Linear regression analysis indicates that 80% (r = 0.907) of the variation in suspended nematode density is correlated with changes in the mean onshore-offshore component of local wind velocity. Nematode turnover associated with spring and summer coastal wind patterns is estimated to be several hundred animals per m2 per day. Once suspended, meiofauna may be carried up to 10 km per day by residual currents in the Sound. Although erosion, transport and deposition of benthic nematodes by wave and current action appears to provide an effective means of dispersal along continental coastlines, the high settling velocity of nematodes suspended in Bogue Sound (on the order of 10-4 m s-1 ) suggests that net downward flux in shelf and slope waters probably prevents their dispersal across ocean basins by surface currents. 相似文献
23.
胶州湾小型底栖生物的丰度和生物量 总被引：33，自引：5，他引：33
1995年 5月— 1 996年 1月 ,在胶州湾北部软底水域进行每 2月一次的调查。结果表明 ,小型底栖生物的年平均丰度为 1 .51× 1 0 6ind/m2 ,最高值出现在 95B1和 95B2站 ,分别为 2 .73× 1 0 6 和 2 .75× 1 0 6ind/m2 ,最低值出现在 95B3站 ,数量为 0 .46× 1 0 6ind/m2 。小型底栖生物的年平均生物量为 1 .32 g/m2 (干重 )。皮尔逊相关分析表明 ,小型生物的数量与以碳和氮表示的浮游植物的生物量呈负相关 ,相关系数分别为 - 0 .969和 - 0 .947(P <0 .0 5)。共鉴定出 1 4个小型生物类群。自由生活的海洋线虫占总数量的 86.6% ,底栖桡足类居第 2位 ,占总数量的 5.7%。按生物量 ,海洋线虫 (35.9% )、介形类 (32 .6% )、多毛类 (1 3.7% )和桡足类 (8.3% )共同构成小型动物的优势类群 ,80 %以上的小型生物分布在 0— 2cm以浅表层内。与国内外同类研究结果进行了比较 ,并对小型生物在胶州湾生态系中的作用进行了探讨 相似文献
24.
Micro-Meiofaunal Community Structure and Nematode Diversity in a Lagoonal Ecosystem (Fangataufa, Eastern Tuamotu Archipelago) 总被引：1，自引：0，他引：1
Abstract. Mciofaunal assemblages in a semi-closed Polynesian atoll have been assessed. High densities, numerous micro- and meiobenthic groups, and 62 diversified (H'= 2.64) nematode species occur. As a whole, the lagoonal habitat may be considered as homogeneous, its variability being controlled by oceanic inflows. 相似文献
25.
David Gwyther Grant J. Batterham Tonny H. Gultom Susetiono 《Marine pollution bulletin》2009,58(6):841-850
The Batu Hijau copper/gold mine in Sumbawa, Indonesia processes ore at approximately 130,000 tpd and discharges tailing via a submarine pipeline to depths below 3000 m at the base of a submarine canyon. The study investigated recolonisation of tailing by meiofauna and its dependence on subsequent accumulation of natural sediment. Microcosm and mesocosm scale experiments were carried out using two tailing and two control samples, the latter comprising defaunated and unaffected natural sediment. All test materials were similar in physical and chemical respects, except for the higher copper concentration in the tailing. The abundances of meiofauna colonising defaunated controls and both tailing samples increased from zero to levels statistically indistinguishable from natural unaffected controls after 97 and 203 days. Colonisation was well established in tailing from freshly mined ore after 40 days, and in oxidized tailing from stockpiled ore after 65 days, and was not dependent on settled natural material. 相似文献
26.
Short and long term effects of a fuel oil spill from a grounded ship "M V Sea Transporter" on meiofauna of a sandy beach of central West Coast of India were investigated. A significant reduction in the absolute abundance of meiofauna was observed immediately after 3 days of spillage particularly at Sinquerim beach, the site of spillage. The reduction was most pronounced in density of nematodes and harpacticoid copepods, which were the most dominant groups. Long-term response showed no apparent oil-induced changes at major taxa levels. The population density improved considerably after the cessation of monsoons with a parallel decrease in petroleum hydrocarbon concentration in the sediment. Nematodes recovered more quickly than benthic copepods. No evidence for this could be due to reproductive dynamics in meiobentos. Although the effect of the oil on meiofauna could be seen initially it could not be proved conclusively on a long-term basis. The effects of the oil spill were confounded with seasonal monsoon effects and beach dynamics. The nematode:copepod ratio and the index of trophic diversity (ITD) were inadequate for detecting oil pollution effects. Therefore it may be concluded that in the presence of other environmental factors acting strongly, the effects of oil on meiofauna was strong but of a temporary nature. 相似文献
27.
The Nazaré Canyon on the Portuguese Margin (NE Atlantic) was sampled during spring-summer for three consecutive years (2005–2007), permitting the first inter-annual study of the meiofaunal communities at the Iberian Margin at two abyssal depths (~3500 m and ~4400 m). Using new and already published data, the meiofauna standing stocks (abundance and biomass) and nematode structural and functional diversity were investigated in relation to the sediment biogeochemistry (e.g. organic carbon, nitrogen, chlorophyll a, phaeopigments) and grain size. A conspicuous increase in sand content from 2005 to 2006 and decrease of phytodetritus at both sites, suggested the occurrence of one or more physical disturbance events. Nematode standing stocks and trophic diversity decreased after these events, seemingly followed by a recovery/recolonisation period in 2007, which was strongly correlated with an increase in the quantity and bioavailability of phytodetrital organic matter supplied. Changes in meiofauna assemblages, however, also differed between stations, likely because of the contrasting hydrodynamic and food supply conditions. Higher meiofauna and nematode abundances, biomass and trophic complexity were found at the shallowest canyon station, where the quantity, quality and bioavailability of food material were higher than at the deeper site. The present results suggest that even though inter-annual variations in the sedimentary environment can regulate the meiofauna in the abyssal Nazaré Canyon, heterogeneity between sampling locations in the canyon were more pronounced. 相似文献
28.
天津近海小型底栖动物丰度研究 总被引：6，自引：1，他引：5
2006年7月至2007年10月在渤海湾天津近海的15个站位,分春、夏、秋、冬4个航次进行了小型底栖动物丰度的调查.通过对未受扰动沉积物样品中的生物分析,共采集到线虫、桡足类、多毛类、介形类、寡毛类、双壳类、动吻类等小型底栖动物类群和少量未鉴定实体,其中线虫为优势类群,占总丰度的90%以上.调查海域小型底栖动物丰度春、夏、秋、冬依次为(405.4±154.8)ind/10cm2,(417.6±38.6)imd/10 cm2,(161.6±64.5)ind/10cm2和204.7±69.7ind/10 cm2,区内的分布以中部海域居多.小型底栖动物丰度值存在季节变化,春季和夏季平均丰度值较高,夏季略高于春季;秋冬季值偏低.小型底柄动物多分布于沉积物0～5 cm层次,占总量的85.9%～92.9%.春季和秋季的小型底栖动物丰度值与沉积物叶绿素a含量显著相关.与我国近海海域研究资料比较显示,目前渤海湾天津近海小型底栖动物丰度值略低. 相似文献
29.
2007年10—11月对南海海域(17—21°N,109—112°E)的小型底栖动物的生态特点进行了研究。结果表明,小型底栖动物的丰度平均为(901±913)ind/10cm2,自近岸向外海域呈递减趋势;平均生物量和生产量分别为(798±713)μgdwt/10cm2和(7185±6421)μgdwt/10cm2。研究海域小型动物的平均丰度与莱州湾和南黄海冬季的研究结果较接近,高于东、黄海,低于胶州湾和长江口。在分选的17个主要类群中,海洋线虫在丰度上占绝对优势(92.9%),多毛类(2.5%)和桡足类(1.5%)所占比例均较小。在生物量上,海洋线虫(41.9%)和多毛类(40.1%)为绝对优势类群,其次是介形类(3.6%)和桡足类(3.2%)。在垂直分布上,占总量约53%的小型底栖动物和52%的海洋线虫分布于0—2cm表层,该结果与长江口较为接近,而较渤海和黄海低。统计分析表明,本海域的小型底栖动物和线虫的数量与沉积物中有机质含量呈显著正相关,与水深呈显著负相关。由海洋线虫与桡足类的数量比(N/C)与本海域环境状况的分析表明,该数值在一定尺度上可为海洋环境监测提供参考。 相似文献