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Full-Text Articles in Life Sciences
Marine Invertebrate Larval Distribution At The Hydrothermal Vent Site Of Gueishandao, Hans-Uwe Dahms, Li-Chun Tseng, Jiang-Shiou Hwang
Marine Invertebrate Larval Distribution At The Hydrothermal Vent Site Of Gueishandao, Hans-Uwe Dahms, Li-Chun Tseng, Jiang-Shiou Hwang
Journal of Marine Science and Technology
Scientists remain uncertain about numerous aspects of hydrothermal vent (HV) ecology, including the reproductive biology of their biota, as well as their recruitment and dispersal during larval stages (meroplankton) in the plankton above the HV sites. We studied the meroplankton from a shallow HV site off the northeastern coast of Taiwan, in the northwest Pacific Ocean. Our findings potentially explain how fauna endemic to HVs persist at specific HV sites. With the exception of some damaged Cnidaria and Ctenophora, the plankton net catches were in good condition and sufficient for identification.
Hydrothermal Vent Effluents Affect Life Stages Of The Copepod Tisbe Sp, Hans-Uwe Dahms, Li-Chun Tseng, Derek Moo-Chul Shim, Jiang-Shiou Hwang
Hydrothermal Vent Effluents Affect Life Stages Of The Copepod Tisbe Sp, Hans-Uwe Dahms, Li-Chun Tseng, Derek Moo-Chul Shim, Jiang-Shiou Hwang
Journal of Marine Science and Technology
We examined the environmental effects of various concentrations of hydrothermal vent (HV) effluents on growth, reproduction, and survivorship of the Tisbe sp. harpacticoid copepod that were retrieved from localities near the vent. Developmental stages (nauplii and copepodids) were exposed to various concentrations of HV effluents in a static renewal culture system. In the survivorship experiments, we tested 3 distinct developmental phases in HV effluent dilutions from 50% to 1%. The HV effluents considerably reduced the survivorship of the naupliar stages at concentrations of >1% (P < 0.05); all nauplii died at concentrations of 25% and 50%. The copepodids were considerably affected at concentrations of >1% in Tisbe sp. (P < 0.05), and no copepodid survived at 50% (P < 0.01). The adult females died at a 50% concentration in Tisbe sp. The developmental duration was not considerably affected in the naupliar or copepodid phases; however, it exhibited a trend of developmental delay. The naupliar development of Tisbe sp. was substantially delayed at a concentration of 10% (P < 0.01), whereas copepodids and adults only exhibited a trend of delayed development with increasing HV concentration. The endpoint mortality exhibited a greater sensitivity to chemical exposure than the endpoint development time. The early developmental stages of Tisbe sp. in both traits were more sensitive to HV effluents than advanced stages. Mortality was a useful toxicological endpoint compared that of developmental duration. We demonstrated that Tisbe sp. may be used in the monitoring of acute and life cycle effects of natural marine pollution caused by HV effluents.
Mortality In The Ocean - With Lessons From Hydrothermal Vents Off Kueishan Tao, Ne-Taiwan, Hans-Uwe Dahms, Jiang-Shiou Hwang
Mortality In The Ocean - With Lessons From Hydrothermal Vents Off Kueishan Tao, Ne-Taiwan, Hans-Uwe Dahms, Jiang-Shiou Hwang
Journal of Marine Science and Technology
There is evidence of plankton mortality and extinction at various temporal and spatial scales induced by man-made pollution, or by natural causes (ageing, competition, predation, diseases, natural pollution). If mortalities take place at large scale they might become of environmental concern and may impact other biotic compartments including fisheries substantially. Such mortalities are a consistent phenomenon at time scales from geological mass extinctions to regularly occurring HABs, that appear to be increasing on a global basis. Several mass mortalities might have escaped our notice for their patchy and erratic occurrences. This also holds for mortalities caused by hydrothermal vents (HVs) …
Life History Of The Copepod Paramphiascella Sp. Affected By Hydrothermal Vent Effluents, Hans-Uwe Dahms, Li-Chun Tseng, Jiang-Shiou Hwang
Life History Of The Copepod Paramphiascella Sp. Affected By Hydrothermal Vent Effluents, Hans-Uwe Dahms, Li-Chun Tseng, Jiang-Shiou Hwang
Journal of Marine Science and Technology
Toxicity of Hydrothermal vent (HV) effluents was tested by investigating the effect on growth and reproduction of the copepod Paramphiascella sp. which was collected and subsequently cultured from localities nearby a shallow marine HV at Kueishan Tao Island, Taiwan. Ontogenetic stages (nauplii, copepodids, and adults) were exposed to a range of concentrations of HV effluents in a static renewal culture system. In a first of two experiments we tested the survivorship of these in HV effluent dilutions from 1 to 50%. HV effluents significantly reduced the survivorship of the naupliar stages at concentrations >5% for Paramphiascella sp. (p < 0.01) and all nauplii died at concentrations of 25% and 50%. Copepodids were significantly letally affected at concentrations >5% (p < 0.01) and all died at 50% (p < 0.01). Developmental duration in Paramphiascella was showing a trend of developmental delay in both phases, in the naupliar and in the copepodid phase. Mortality showed a greater sensitivity to chemical exposure than development time. Among both traits were early developmental stages of Paramphiascella sp. more sensitive to HV effluents than advanced stages. We showed that Paramphiascella sp. was a useful test organism in the monitoring of life cycle as well as acute effects of HV effluents being present for millions of years and providing unique ecosystems. Mortality was a useful toxicological endpoint whereas developmental duration was not.