Successful invasion of Mnemiopsis leidyi A. Agassiz, 1865 and Beroe ovata Mayer, 1912 into the Black Sea and their important role in this region pelagic ecosystem is stipulated mainly by the considerable eurythermy of...Successful invasion of Mnemiopsis leidyi A. Agassiz, 1865 and Beroe ovata Mayer, 1912 into the Black Sea and their important role in this region pelagic ecosystem is stipulated mainly by the considerable eurythermy of these species. Many ecological-physiological characteristics of ctenophores—aliens are studied quite well. However, bioluminescence, one of the most important elements of the ctenophores ecology and the bioluminescence reaction temperature optimum for these individuals under different environment temperatures were not studied sufficiently. Therefore our researches in this scientific field are significant and conceptually novel for ctenophores ecology study. Experimental investigations were carried out in the period of 2008-2009 in the IBSS. Uni-sized (40 mm) ctenophores were collected in the Sevastopol coastal zone and divided in several groups, contained under different temperatures: from 10°C ± 1°C to 30°C ± 1°C. Ctenophore bioluminescence was investigated under chemical and mechanical stimulation. M. leidyi light emission maximal amplitude (1432.94 ± 71.64 × 108 quantum·s–1·cm–2) with duration of 3.54 ± 0.15 s is fixed under the temperature of 26°C ± 1°C. Temperature increase up to 30°C ± 1°C led to the 4 times decrease of the bioluminescence intensity. Under temperature decrease up to 10°C ± 1°C this parameter decreased 20 times (p B. ovata achieved maximal values under the temperature of 22°C ± 1°C (1150.12 ± 57.51 × 108 quantum·s–1·cm–2) with duration of 3.03 ± 0.15 s. The luminescence intensity decreased under the temperature increase to 30°C ± 1°C more than 20 times. Temperature decrease to the values of 10°C ± 1°C impacted decreasing the amplitude of bioluminescence up to the minimal –4.92 ± 0.22 × 108 quantum·s–1·cm–2. The data obtained testify that characteristics of the ctenophores bioluminescence can be conditioned not only by the modification the environment temperature but by the variability of their physiological condition.展开更多
Many ecological-physiological characteristics of ctenophores-aliensMnemiopsis leidyi A. Agassiz, 1865 and Beroe ovata Mayer, 1912 are studied quite well because they play a very important ecological role in the Black ...Many ecological-physiological characteristics of ctenophores-aliensMnemiopsis leidyi A. Agassiz, 1865 and Beroe ovata Mayer, 1912 are studied quite well because they play a very important ecological role in the Black Sea ecosystem. However, bioluminescence, one of the most important elements of the ctenophores ecology and its connection with feeding regime were not studied sufficiently. Experiments have shown that characteristics of the ctenophores bioluminescence differed considerably in dependence of food supplies. Thus, amplitude and light-emitting energy of the fed ctenophores B. ovata are maximal, 3 times more than analogical indices of the just-caught individuals and 4 times more than ones of starving individuals. More prolonged flash signal (to 3.5 s), which exceeds light-emitting duration of the starving individuals twice, can be registered from the fed ctenophores. Investigation of the M. leidyi bioluminescence has shown that amplitude and light-emitting energy of the just-caught ctenophores were two times more than those of the starving individuals. At the same time, light-emitting amplitude of the fed individuals is 6.5 times and light-emitting energy is 3 - 4 times higher than that of the just-caught ctenophores. The light-emitting duration of the starving and justcaught organisms is practically the same. The most prolonged signal is registered from the fed ctenophores—up to 2.8 s. The data obtained testify that characteristics of the ctenophores bioluminescence can be conditioned not only by nutritional value but by the composition of the food as well.展开更多
文摘Successful invasion of Mnemiopsis leidyi A. Agassiz, 1865 and Beroe ovata Mayer, 1912 into the Black Sea and their important role in this region pelagic ecosystem is stipulated mainly by the considerable eurythermy of these species. Many ecological-physiological characteristics of ctenophores—aliens are studied quite well. However, bioluminescence, one of the most important elements of the ctenophores ecology and the bioluminescence reaction temperature optimum for these individuals under different environment temperatures were not studied sufficiently. Therefore our researches in this scientific field are significant and conceptually novel for ctenophores ecology study. Experimental investigations were carried out in the period of 2008-2009 in the IBSS. Uni-sized (40 mm) ctenophores were collected in the Sevastopol coastal zone and divided in several groups, contained under different temperatures: from 10°C ± 1°C to 30°C ± 1°C. Ctenophore bioluminescence was investigated under chemical and mechanical stimulation. M. leidyi light emission maximal amplitude (1432.94 ± 71.64 × 108 quantum·s–1·cm–2) with duration of 3.54 ± 0.15 s is fixed under the temperature of 26°C ± 1°C. Temperature increase up to 30°C ± 1°C led to the 4 times decrease of the bioluminescence intensity. Under temperature decrease up to 10°C ± 1°C this parameter decreased 20 times (p B. ovata achieved maximal values under the temperature of 22°C ± 1°C (1150.12 ± 57.51 × 108 quantum·s–1·cm–2) with duration of 3.03 ± 0.15 s. The luminescence intensity decreased under the temperature increase to 30°C ± 1°C more than 20 times. Temperature decrease to the values of 10°C ± 1°C impacted decreasing the amplitude of bioluminescence up to the minimal –4.92 ± 0.22 × 108 quantum·s–1·cm–2. The data obtained testify that characteristics of the ctenophores bioluminescence can be conditioned not only by the modification the environment temperature but by the variability of their physiological condition.
文摘Many ecological-physiological characteristics of ctenophores-aliensMnemiopsis leidyi A. Agassiz, 1865 and Beroe ovata Mayer, 1912 are studied quite well because they play a very important ecological role in the Black Sea ecosystem. However, bioluminescence, one of the most important elements of the ctenophores ecology and its connection with feeding regime were not studied sufficiently. Experiments have shown that characteristics of the ctenophores bioluminescence differed considerably in dependence of food supplies. Thus, amplitude and light-emitting energy of the fed ctenophores B. ovata are maximal, 3 times more than analogical indices of the just-caught individuals and 4 times more than ones of starving individuals. More prolonged flash signal (to 3.5 s), which exceeds light-emitting duration of the starving individuals twice, can be registered from the fed ctenophores. Investigation of the M. leidyi bioluminescence has shown that amplitude and light-emitting energy of the just-caught ctenophores were two times more than those of the starving individuals. At the same time, light-emitting amplitude of the fed individuals is 6.5 times and light-emitting energy is 3 - 4 times higher than that of the just-caught ctenophores. The light-emitting duration of the starving and justcaught organisms is practically the same. The most prolonged signal is registered from the fed ctenophores—up to 2.8 s. The data obtained testify that characteristics of the ctenophores bioluminescence can be conditioned not only by nutritional value but by the composition of the food as well.
