[Objective] The research aimed to investigate the bioturbation effects of Branchiura sowerbyi （Tubificidae） on the vertical transport of sedimentary particles in paddy field,and explore the bioturbation effects and ...[Objective] The research aimed to investigate the bioturbation effects of Branchiura sowerbyi （Tubificidae） on the vertical transport of sedimentary particles in paddy field,and explore the bioturbation effects and mechanism of benthic Annelida in coupling process of benthic-pelagic interface.[Method]Using chemically stable glass beads as tracers,the vertical transport of sedimentary particles in paddy field was analyzed comparatively with and without B.sowerbyi.[Result]After 10 days＇ bioturbation of B.sowerbyi,41.3% of the glass beads on the surface of sedimentary particles were transferred downward to the maximum depth of 9.4 cm,and the vertical transportation rate of sedimentary particles was 1.370×10-3/（g·cm2·d）. 25.8% and 17.3% of glass beads at a depth of 6 cm were transferred upwards and downwards respectively after bioturbation,to the maximum depth of 5.2 and 2.7 cm respectively,and the vertical transportation rates of sedimentary particles were 8.557×10-4 and 5.738×10-4/（g·cm2·d） respectively.[Conclusion]The sedimentary particles on the surface and deep layer of the paddy field were vertically shifted by the physical activities of B.sowerbyi,thus changed the sedimentary environment.展开更多
An April 1996 to March 1997 comparative study on the abundance and secondary production of Branchiura sowerbyi Beddard, 1892 in two typical shallow lakes showed that in Houhu, an algae dominated lake, the worm density...An April 1996 to March 1997 comparative study on the abundance and secondary production of Branchiura sowerbyi Beddard, 1892 in two typical shallow lakes showed that in Houhu, an algae dominated lake, the worm density (68 ind·m -2 ) peaked in July, biomass (1.930 g·m -2 ) peaked in June, while in Biandantang, a macrophyte dominated lake, standing stock (density:60 ind·m - 2 ; biomass:1.019 g·m -2 in wet weight) peaked in December. Secondary production of the animal in Houhu Lake was 3.413 g wet wt m -2 a -1 , a little more than that (2.675 g wet wt m -2 a -1 ) in Biandantang Lake. Their turnover rates (P/B ratios) were 4.0 and 5.0, respectively.展开更多
To explore the life cycle of Craspedacusta, the authors collected male and female specimens of the Craspedacusta sowerbyi xinyangensis in a small fire-fighting pond in Ningbo, Zhejiang Province in July, 2005 and 2006....To explore the life cycle of Craspedacusta, the authors collected male and female specimens of the Craspedacusta sowerbyi xinyangensis in a small fire-fighting pond in Ningbo, Zhejiang Province in July, 2005 and 2006. The development of C. sowerbyi xinyangensis was studied from zygote to medusa by means of light microscopy and digital camera. The zygotes of C. sowerbyi xinyangensis are globular and smooth （90- 105 μm diameter） and have an equal, total cleavage to the two-cell stage 15 min after fertilization. The embryos enter the four-cell stage after another 15 min and become multicellular embryos after 3h 15min. At this stage the embryos have a diameter similar to fertilized eggs but have uneven surfaces that are distinct from the smooth surfaces of the uncleaved zygotes. Solid gastrulae are formed 7 h after fertilization. These are spherical planulae with short surface cilia that begin to swim in slow clockwise circles. After 12 h, they lose their cilia, cease swimming and become elongated planulae with one end larger than the other. Rod-like planulae, similar in thickness at both ends, are formed after an additional 7 h. After 4 days, the planulae develop into tiny polyps having two germ layers and a gastrovascular cavity. The polyp mouth is 50 - 62 μm in diameter, lacking tentacles but having nematocysts around the mouth. Planulae become mature polyps after 10 days （15 days after fertilization）. Medusa buds （45 - 88 μm diameter） are formed by polyp budding, which soon become free-living medusae with 8 tentacles （380 - 620 μm diameters） . Sometimes, the movement of frustules, which are formed by the polyps and similar to planulae in morphology can also be observed [ Current Zoology 55 （3） ： 227 - 234, 2009].展开更多
The energy flow of Branchiura sowerbyi was studied for the first time in China in a shallow macrophytic lake, Biandantang Lake, Hubei Province. The energy flow was calculated from the measurement of flesh production (...The energy flow of Branchiura sowerbyi was studied for the first time in China in a shallow macrophytic lake, Biandantang Lake, Hubei Province. The energy flow was calculated from the measurement of flesh production (12.5241kJ/m2a), egestion (517.7302kJ/m2a), metabolism (38.3273 kJ/m2a), and excretion (4.3798kJ/m2a). The net growth efficiency of the species is about 22.7%, which accords well with the generally reported value for oligochaetes. In addition, the relationship between starvation respiration (R, mgO2/ind穌), wet weight (Ww, mg) and temperature (T, C) were also measured, with the regression function being R=0.008 Ww0.736 e0.050T.展开更多
基金Supported by National Natural Science Foundation of China(31070421 )Human Resources and Social Security Department Students Abroad Science and Technology Activities Preferred Foundation (Human and Social Council Issued 2008-86)+8 种基金Talent Development Fund Project in Jilin Province (Jilin 2007-259)Jilin Province Science and Technology Development Project (20060577 )Technology Project Jilin Provincial Ministry of Education (20094352006113 20071692010150)The Project Sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry (2005-546)Changchun Normal University Natural Science Foundation(2009002)Northeast Normal University Natural Science Foundation for Young Scholar(20050406)~~
文摘[Objective] The research aimed to investigate the bioturbation effects of Branchiura sowerbyi （Tubificidae） on the vertical transport of sedimentary particles in paddy field,and explore the bioturbation effects and mechanism of benthic Annelida in coupling process of benthic-pelagic interface.[Method]Using chemically stable glass beads as tracers,the vertical transport of sedimentary particles in paddy field was analyzed comparatively with and without B.sowerbyi.[Result]After 10 days＇ bioturbation of B.sowerbyi,41.3% of the glass beads on the surface of sedimentary particles were transferred downward to the maximum depth of 9.4 cm,and the vertical transportation rate of sedimentary particles was 1.370×10-3/（g·cm2·d）. 25.8% and 17.3% of glass beads at a depth of 6 cm were transferred upwards and downwards respectively after bioturbation,to the maximum depth of 5.2 and 2.7 cm respectively,and the vertical transportation rates of sedimentary particles were 8.557×10-4 and 5.738×10-4/（g·cm2·d） respectively.[Conclusion]The sedimentary particles on the surface and deep layer of the paddy field were vertically shifted by the physical activities of B.sowerbyi,thus changed the sedimentary environment.
文摘An April 1996 to March 1997 comparative study on the abundance and secondary production of Branchiura sowerbyi Beddard, 1892 in two typical shallow lakes showed that in Houhu, an algae dominated lake, the worm density (68 ind·m -2 ) peaked in July, biomass (1.930 g·m -2 ) peaked in June, while in Biandantang, a macrophyte dominated lake, standing stock (density:60 ind·m - 2 ; biomass:1.019 g·m -2 in wet weight) peaked in December. Secondary production of the animal in Houhu Lake was 3.413 g wet wt m -2 a -1 , a little more than that (2.675 g wet wt m -2 a -1 ) in Biandantang Lake. Their turnover rates (P/B ratios) were 4.0 and 5.0, respectively.
基金funded by Program for Changjiang Scholar and Innovative Research Teamin University(IRT0734)The Natural Science Foundation of Zhejiang Province(No.Y307063)Zhejiang Education Bureau(No.20061639)
文摘To explore the life cycle of Craspedacusta, the authors collected male and female specimens of the Craspedacusta sowerbyi xinyangensis in a small fire-fighting pond in Ningbo, Zhejiang Province in July, 2005 and 2006. The development of C. sowerbyi xinyangensis was studied from zygote to medusa by means of light microscopy and digital camera. The zygotes of C. sowerbyi xinyangensis are globular and smooth （90- 105 μm diameter） and have an equal, total cleavage to the two-cell stage 15 min after fertilization. The embryos enter the four-cell stage after another 15 min and become multicellular embryos after 3h 15min. At this stage the embryos have a diameter similar to fertilized eggs but have uneven surfaces that are distinct from the smooth surfaces of the uncleaved zygotes. Solid gastrulae are formed 7 h after fertilization. These are spherical planulae with short surface cilia that begin to swim in slow clockwise circles. After 12 h, they lose their cilia, cease swimming and become elongated planulae with one end larger than the other. Rod-like planulae, similar in thickness at both ends, are formed after an additional 7 h. After 4 days, the planulae develop into tiny polyps having two germ layers and a gastrovascular cavity. The polyp mouth is 50 - 62 μm in diameter, lacking tentacles but having nematocysts around the mouth. Planulae become mature polyps after 10 days （15 days after fertilization）. Medusa buds （45 - 88 μm diameter） are formed by polyp budding, which soon become free-living medusae with 8 tentacles （380 - 620 μm diameters） . Sometimes, the movement of frustules, which are formed by the polyps and similar to planulae in morphology can also be observed [ Current Zoology 55 （3） ： 227 - 234, 2009].
基金Project supported by NSFC (30270278 3960019)+1 种基金 the foundation of the government of Hubei Province (No. 2000J109) and the foundation of
文摘The energy flow of Branchiura sowerbyi was studied for the first time in China in a shallow macrophytic lake, Biandantang Lake, Hubei Province. The energy flow was calculated from the measurement of flesh production (12.5241kJ/m2a), egestion (517.7302kJ/m2a), metabolism (38.3273 kJ/m2a), and excretion (4.3798kJ/m2a). The net growth efficiency of the species is about 22.7%, which accords well with the generally reported value for oligochaetes. In addition, the relationship between starvation respiration (R, mgO2/ind穌), wet weight (Ww, mg) and temperature (T, C) were also measured, with the regression function being R=0.008 Ww0.736 e0.050T.
