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海洋生物监测新技术探索:幼虫变态实验 总被引:5,自引:0,他引:5
回顾了近年来海洋环境污染生物监测中的海洋底栖无脊椎动物早期发育和变态阶段的毒性实验的研究进展,强调应根据敏感性和代表性水平来选取生物有机体进行生物毒性实验,并探讨了运用幼虫变态实验来进行海洋污染监测的可行性。 相似文献
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刺参幼虫的变态和习性 总被引:4,自引:0,他引:4
廖承义 《山东海洋学院学报》1987,17(1):85-95
刺参幼虫的发育可分为浮游和底栖两个阶段.浮游生活阶段包括三个幼虫期。它的特征是体表具有分布不同的纤毛。在囊胚期为周身纤毛,耳状幼虫期为纵行纤毛带,樽形幼虫为五条围绕幼虫身体的环形纤毛带.自五触手幼虫开始,原来的纤毛环逐渐退化.即进入第二阶段底栖生活阶段.从耳状幼虫期至樽形幼虫期.幼虫的体长发生急剧的缩短,形成了幼虫发育的一种特殊生长曲线(见图表)。从樽形幼虫变态成五触手幼虫的时间很短(在水温为20-24℃下为卜2天),这是幼虫发育的最关键时期。水体腔的变化是幼虫发育正常与否的重要标志。本文对水体腔的变化作了详细的描述.并指出了它在幼虫发育中的意义.特别是在人工育苗中可作为鉴别幼虫发育正常与否的重要依据。 相似文献
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紫海胆浮游幼虫人工诱导变态试验 总被引:1,自引:2,他引:1
海胆人工苗个体生长差异很大[1]。浮游幼虫变态参差不齐是造成附着后个体生长差异的重要原因。所以,人工诱导浮游幼虫变态在海胆苗种生产中具有重要的现实意义。作者于1999年在紫海胆 (Anthocidariscrassispina)人工育苗试验中,发现紫海胆浮游幼虫变态时间差异很大,早的11d(受精后 )即变态,而迟的25d仍未变态。1材料与方法1.1材料人工催产、授精,人工培育的紫海胆幼虫,采用受精后18d的八腕长腕幼虫进行实验。1.2方法1.2.1500ml玻璃烧杯,每个放紫海胆浮游幼虫约100只,用… 相似文献
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几种诱导物质对皱纹盘鲍幼虫变态的相互作用 总被引:1,自引:0,他引:1
本文研究用不同浓度的氯化钾(KCl)、γ-氨基丁酸(GABA)和足粘液相结合对皱纹盘鲍幼虫变态的影响,从中找出皱纹盘鲍幼虫诱导变态的最佳条件,为人工育苗提供科学依据。 相似文献
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为了探讨广泛存在于海中基质表面的微生物粘膜对鲍幼虫附着和变态的诱导作用,研究了不同年龄微生物粘膜 ( 1 ~ 6 d ) 对杂色鲍幼虫附着和变态的影响.结果表明:1 ~ 6 d微生物粘膜均显著地诱导幼虫附着,其中 3, 5 和 6 d 微生物粘膜还显著地诱导幼虫变态;幼虫的附着率和变态率分别与微生物粘膜中的藻类密度和细菌密度呈显著的正相关性,推测藻类和细菌可能在幼虫的附着和变态中起着重要作用.垂直基质选择性试验结果表明,90 % 以上的幼虫附着在具 23 d 微生物粘膜的载玻片表面且变态率达 70 % 以上,进一步证实了微生物粘膜可以诱导杂色鲍幼虫的附着和变态,同时也证实了幼虫具备选择附着基质的能力. 相似文献
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Abstract. The influence of bacterial exopolymers and conspecific adult extract of Balanus amphitrite on metamorphosis of cyprid larvae at different salinities has been evaluated through laboratory assay. The bacterial exopolymers epm extracted from Pseudomonas, Acinetobacter and Enterobacteriaceae strains, isolated from the shell surface of Balanus amphitrite , were examined for their influence on metamorphosis, both individually and in combination with conspecific adult extract at 15, 25, 35 and 45% salinities. The epm extracted from the pool of these three strains mixed culture was also tested similarly.
The influence of epm varied with the strain of bacteria and salinity. The surface condition and time interval significantly influenced the metamorphosis rate. The interaction between these two variables, however, did not change in any combination, irrespective of the bacterial strain used. The Pseudomonas epm promoted metamorphosis at 15%, but was inhibitory at 45%. The Acinetobacter epm induced metamorphosis to a level of 71 ± 15% at 15%. No such metamorphosis promotion was observed with the epm of this strain at higher salinities and the influence was less than the conspecific adult extract. The epm of Enterobacteriaceae and mixed culture epm did not promote metamorphosis. There was no appreciable change in the metamorphic rate in the control conditions at 25%, 35% and 45% salinities and the rate was much lower than that obtained with conspecific adult extract. At 15%, however, the influence of adult extract was closer to that of the control condition. This shows that even in the absence of any attractant, the settlement intensity is positively influenced at mid-salinity of the barnacles' natural distributional range. 相似文献
The influence of epm varied with the strain of bacteria and salinity. The surface condition and time interval significantly influenced the metamorphosis rate. The interaction between these two variables, however, did not change in any combination, irrespective of the bacterial strain used. The Pseudomonas epm promoted metamorphosis at 15%, but was inhibitory at 45%. The Acinetobacter epm induced metamorphosis to a level of 71 ± 15% at 15%. No such metamorphosis promotion was observed with the epm of this strain at higher salinities and the influence was less than the conspecific adult extract. The epm of Enterobacteriaceae and mixed culture epm did not promote metamorphosis. There was no appreciable change in the metamorphic rate in the control conditions at 25%, 35% and 45% salinities and the rate was much lower than that obtained with conspecific adult extract. At 15%, however, the influence of adult extract was closer to that of the control condition. This shows that even in the absence of any attractant, the settlement intensity is positively influenced at mid-salinity of the barnacles' natural distributional range. 相似文献
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Benthic foraminifera are increasingly used as environmental bio-indicators of pollution in coastal and marginal marine settings. Their community structure provides information on the general characteristics of the environment and some species are sensitive to specific environmental parameters. Among various criteria, the occurrence of test abnormalities may represent a useful bioindicator for monitoring environmental impacts in coastal regions. A study of living benthic foraminifera was carried out in 42 sediment samples collected from the central Adriatic coast of Italy. Benthic foraminiferal assemblages from this area are rich, well preserved, and dominated by Ammonia parkinsoniana, and subordinately by Ammonia tepida, Aubignyna perlucida, Eggerella scabra, and Nonionella turgida. Heavy metal concentrations have been analysed which indicate low polluted environmental conditions. Foraminiferal species and heavy metal concentrations were investigated both with bivariate (correlation matrix) and multivariate techniques of principal component analysis (PCA) and cluster analysis. Statistical analysis shows a possible control of these pollutants both on the taxonomic composition of the benthic foraminiferal assemblages and the development of test malformations. Increasing heavy metal contents lead to an increase in relative abundance of A. tepida A. perlucida, N. turgida and E. scabra, and a relative concurrent decrease in relative abundance of A. parkinsoniana and higher percentages of deformed specimens (FAI) and species (FMI). Our results confirm that A. parkinsoniana prefers clean to low polluted environments and show that it is a very sensitive and un-tolerant species to heavy metal pollution being deeply affected by heavy metal content even at low concentrations. Our findings also confirm the capacity of the A. tepida to tolerate increasing heavy metal concentrations, and highlights that A. perlucida, N. turgida and E. scabra can be considered as tolerant species at least in low polluted environments. Following this, A. parkinsoniana and A. tepida can be reciprocally considered good bioindicator of heavy metal pollution over the surveyed area. The development of test abnormalities with a variety of malformations is a noticeable feature over the study area where the living deformed assemblages are largely dominated by a few species. The low percentages of deformed specimens (Foraminiferal Abnormality Index up to 4.7, with 2 on average) match well with the low concentrations of heavy metals that lead to low polluted environmental conditions. This study confirms and supports the suitability of studying benthic foraminifera as a technique for the in situ continuous bio-monitoring of heavy metal pollution of coastal marine sediments. 相似文献