Year-round investigations were carried out to address the population dynamics of amphipod Ampithoe val- ida and its potential regulating factors in the Yundang Lagoon （a eutrophic subtropical coastal lagoon in Xiamen...Year-round investigations were carried out to address the population dynamics of amphipod Ampithoe val- ida and its potential regulating factors in the Yundang Lagoon （a eutrophic subtropical coastal lagoon in Xiamen City, China） from October 2007 to October 2008. The results show that A. valida population was largely composed of juveniles and reached a peak abundance （12.02× 10^3 ind./m2） in March, but sharply shrunk in July. The monthly variation pattern ofA. valida seemed to follow that of Ulva lactuca which is the main food resource for A. valida, indicating a strong influence of food availability on A. valida popu- lation dynamics. Life cycle studies in laboratory indicate that A. valida adopted an r-selected life strategy, e.g., rapid growth rate （0.216-0.302 mm/d）, consecutive breeding （4-10 times）, short reproductive rhythm （9-17 d） and huge fecundity （24-192 eggs or 6-94 juveniles per brood）, which contributed to the fast pop- ulation growth ofA. valida from January to March. Although temperature may also be a significant cause, A. valida could grow quickly and show normal reproductive traits （i.e., the timing of sexual differentiation or maturity, the reproductive rhythm, the number of broods all through its lifespan and offspring produc- tion） in temperature between 15-30~ C. Therefore, the temperature variation in the lagoon water should not account for the sharp variation of A. valida population by affecting the survival, growth and reproduction of the amphipod. However, negative correlation between water temperature and U. lactuca biomass in the lagoon suggested that temperature could have indirectly affected the population dynamics ofA. ualida by affecting its food availability. The authors conclude that, in the Yundang Lagoon, the population dynamics ofA. validawas mainly controlled by the food availability rather than water temperature.展开更多
The marine green algae genus Chaetomorpha is a common source of“green tide”and is widespread on coasts around the world.In this study,based on invasive Chaetomorpha valida collected from the Shandong Peninsula,the m...The marine green algae genus Chaetomorpha is a common source of“green tide”and is widespread on coasts around the world.In this study,based on invasive Chaetomorpha valida collected from the Shandong Peninsula,the morphogenesis and reproductive characteristics of two strains that are morphologically different from each other,were observed using experimental biology methods.The main results are as follows:(1)significant difference in the size of reproductive cells produced by Strains 1 and 2;(2)gametes produced by Strain 2 are isogamous and same gametangial during the binding process of gametes,whereas those of Strain 1 are isogamous but hetero-cystic;(3)progeny from Strain 1 has rhizoidal holdfast,whereas that of Strain 2 has discoid holdfast;(4)gametophytic“branching”was found in Strain 1.These results could validate the high phenotypic plasticity of macroalgae and offered an interpretation of habitat adaptation.Furthermore,this study innovatively provided fundamental research on the selection of macroalgal traits and explored competitive strategies for the dominant survival of macroalgae from a new perspective.展开更多
The Gross growth efficiency （GGE） is defined as the amount of consumer carbon produced relative to the amount of prey ingested in a given time interval. In population ecology, it can be considered as an index for th...The Gross growth efficiency （GGE） is defined as the amount of consumer carbon produced relative to the amount of prey ingested in a given time interval. In population ecology, it can be considered as an index for the ability of a consumer to convert the biomass of food into its population production. In this study, it was firstly applied to estimate the role of amphipods grazing in the biomass dynamics of macroalgae （Ulva lactuca） in Yundang Lagoon （a subtropical eutrophic coastal lagoon, Xiamen City, China）. It was found that amphipods were the dominant group （82.2%-98.7%） in the benthic assemblage, in which five amphipod species （Corophium uenoi, Ampithoe valida, Grandidierella japonica, Grammaropsis laevipalmata andCa-prella panantis） were observed in the lagoon. However, onlyA. valida significantly consumedU. lactuca among these amphipod species. A series of experiments were conducted to estimate the consumption of U. lactuca byA. valida. It was suggested that the monthly secondary production （P） ofA. valida using size frequency method ranged from 2.39 to 13.68 g/m2.GGEofA. valida exponentially reduced with body size and was closely associated with water temperature. Therefore,GGE equation for different months using the temperature recorded during the field investigation was fitted. The monthly consumption ofU. lactuca was figured out to be 86.7-1 549.0 g/m2 by the sum of consumption （P/GGE） byA. valida at different size, ac-counting for 2.0%-37.5% ofU. lactucaproduction. It indicates that the grazing effect ofA. valida did play a role in reducingthe accumulation ofU. lactucabiomass whenA. valida was abundant, but it finally fails to limit the U. lactucagrowth in Yundang Lagoon. Low abundance of A. valida and high nutrient loading may be two major reasons for the outbreak ofU. lactuca bloom in the lagoon.展开更多
The marine green alga Chaetomorpha valida fouls aquaculture ponds along the coastal cities of Dalian and Rongcheng, China. Unialgal cultures were observed under a microscope to determine the developmental morphologica...The marine green alga Chaetomorpha valida fouls aquaculture ponds along the coastal cities of Dalian and Rongcheng, China. Unialgal cultures were observed under a microscope to determine the developmental morphological characters of C. valida. Results reveal that gametophytic filaments often produce lateral branches under laboratory culture conditions, suggesting an atypical heteromorphic life cycle of C. valida between unbranched sporophytes and branched gametophytes, which differs from typical isomorphic alternation of Chaetomorpha species. The shape of the basal attachment cell, an important taxonomic character within the genus, was found variable depending on environmental conditions. The 18S rDNA and 28S rDNA regions were used to explore the phylogenetic affinity of the taxa. Inferred trees from 18S rDNA sequences revealed a close relationship between C. valida and Chaetomorpha moniligera. These results would enrich information in general biology and morphological plasticity of C. valida and provided a basis for future identification of green tide forming algae.展开更多
Meromictic lakes are interesting objects for study in terms of paleolimnology.The lamination of the bottom sediments well expressed in these lakes.It is related with permanent stratification of the water column.Throug...Meromictic lakes are interesting objects for study in terms of paleolimnology.The lamination of the bottom sediments well expressed in these lakes.It is related with permanent stratification of the water column.Through this展开更多
This paper presents results from a statistical validation of the hindcasts of surface wind by a high-reso-ution-mesoscale atmospheric numerical model Advanced Research WRF （ARW3.3）, which is set up to force the oper...This paper presents results from a statistical validation of the hindcasts of surface wind by a high-reso-ution-mesoscale atmospheric numerical model Advanced Research WRF （ARW3.3）, which is set up to force the operational coastal ocean forecast system at Indian Na- tional Centre for Ocean Information Services （INCOIS）. Evaluation is carried out based on comparisons of day-3 forecasts of surface wind with in situ and remote-sensing data. The results show that the model predicts the surface wind fields fairly accurately over the west coast of India, with high skill in predicting the surface wind during the pre-monsoon season. The model predicts the diurnal variability of the surface wind with reasonable accuracy. The model simulates the land-sea breeze cycle in the coastal region realistically, which is very clearly observed during the northeast monsoon and pre-monsoon season and is less prominent during the southwest monsoon season.展开更多
In order to produce macromolecules by using the immobilized cells in microcapsules, a novel macro-porous NaCS-PDMDAAC capsules system was used to immobilize Candida valida in a semi-continuous culture mode for produci...In order to produce macromolecules by using the immobilized cells in microcapsules, a novel macro-porous NaCS-PDMDAAC capsules system was used to immobilize Candida valida in a semi-continuous culture mode for producing lipase. It was found that the encapsulation system had no negative effect on the growth and lipase productivity, and the lipase produced inside capsules could diffuse freely to the media outside capsules. The cultivation with the capsules was carried out for 15 batches and the lipase in each batch had almost the same activity. In comparison with free cell cultivation, the immobilized cell fermentation shortened obviously the period of glucose consumption from 24 hours to 8 hours and increased lipase productivity.展开更多
基金Public Science and Technology Research Funds Projects of Ocean under contract No.201205009-3Key Sci-Tech Program of Xiamen City under contract No.3502Z20102004
文摘Year-round investigations were carried out to address the population dynamics of amphipod Ampithoe val- ida and its potential regulating factors in the Yundang Lagoon （a eutrophic subtropical coastal lagoon in Xiamen City, China） from October 2007 to October 2008. The results show that A. valida population was largely composed of juveniles and reached a peak abundance （12.02× 10^3 ind./m2） in March, but sharply shrunk in July. The monthly variation pattern ofA. valida seemed to follow that of Ulva lactuca which is the main food resource for A. valida, indicating a strong influence of food availability on A. valida popu- lation dynamics. Life cycle studies in laboratory indicate that A. valida adopted an r-selected life strategy, e.g., rapid growth rate （0.216-0.302 mm/d）, consecutive breeding （4-10 times）, short reproductive rhythm （9-17 d） and huge fecundity （24-192 eggs or 6-94 juveniles per brood）, which contributed to the fast pop- ulation growth ofA. valida from January to March. Although temperature may also be a significant cause, A. valida could grow quickly and show normal reproductive traits （i.e., the timing of sexual differentiation or maturity, the reproductive rhythm, the number of broods all through its lifespan and offspring produc- tion） in temperature between 15-30~ C. Therefore, the temperature variation in the lagoon water should not account for the sharp variation of A. valida population by affecting the survival, growth and reproduction of the amphipod. However, negative correlation between water temperature and U. lactuca biomass in the lagoon suggested that temperature could have indirectly affected the population dynamics ofA. ualida by affecting its food availability. The authors conclude that, in the Yundang Lagoon, the population dynamics ofA. validawas mainly controlled by the food availability rather than water temperature.
基金Supported by the National Natural Science Foundation of China(Nos.32270219,31970216)。
文摘The marine green algae genus Chaetomorpha is a common source of“green tide”and is widespread on coasts around the world.In this study,based on invasive Chaetomorpha valida collected from the Shandong Peninsula,the morphogenesis and reproductive characteristics of two strains that are morphologically different from each other,were observed using experimental biology methods.The main results are as follows:(1)significant difference in the size of reproductive cells produced by Strains 1 and 2;(2)gametes produced by Strain 2 are isogamous and same gametangial during the binding process of gametes,whereas those of Strain 1 are isogamous but hetero-cystic;(3)progeny from Strain 1 has rhizoidal holdfast,whereas that of Strain 2 has discoid holdfast;(4)gametophytic“branching”was found in Strain 1.These results could validate the high phenotypic plasticity of macroalgae and offered an interpretation of habitat adaptation.Furthermore,this study innovatively provided fundamental research on the selection of macroalgal traits and explored competitive strategies for the dominant survival of macroalgae from a new perspective.
基金The Natural Science Foundation of Fujian Province under contract No.2014J01127the Public Science and Technology Research Funds Projects of Ocean under contract Nos 201205009-3 and 201105012
文摘The Gross growth efficiency （GGE） is defined as the amount of consumer carbon produced relative to the amount of prey ingested in a given time interval. In population ecology, it can be considered as an index for the ability of a consumer to convert the biomass of food into its population production. In this study, it was firstly applied to estimate the role of amphipods grazing in the biomass dynamics of macroalgae （Ulva lactuca） in Yundang Lagoon （a subtropical eutrophic coastal lagoon, Xiamen City, China）. It was found that amphipods were the dominant group （82.2%-98.7%） in the benthic assemblage, in which five amphipod species （Corophium uenoi, Ampithoe valida, Grandidierella japonica, Grammaropsis laevipalmata andCa-prella panantis） were observed in the lagoon. However, onlyA. valida significantly consumedU. lactuca among these amphipod species. A series of experiments were conducted to estimate the consumption of U. lactuca byA. valida. It was suggested that the monthly secondary production （P） ofA. valida using size frequency method ranged from 2.39 to 13.68 g/m2.GGEofA. valida exponentially reduced with body size and was closely associated with water temperature. Therefore,GGE equation for different months using the temperature recorded during the field investigation was fitted. The monthly consumption ofU. lactuca was figured out to be 86.7-1 549.0 g/m2 by the sum of consumption （P/GGE） byA. valida at different size, ac-counting for 2.0%-37.5% ofU. lactucaproduction. It indicates that the grazing effect ofA. valida did play a role in reducingthe accumulation ofU. lactucabiomass whenA. valida was abundant, but it finally fails to limit the U. lactucagrowth in Yundang Lagoon. Low abundance of A. valida and high nutrient loading may be two major reasons for the outbreak ofU. lactuca bloom in the lagoon.
基金Supported by General and Major Projects of the National Natural Science Foundation of China(Nos.31070185,31093440)the Science and Technology Project of Guangdong Province(Nos.2011B031100010,2012A020200007)+3 种基金the Talent Introduction Projects of Guangdong Province Universities and Collegesthe Team Project of Natural Science Foundation of Guangdong Province(No.S2011030005257)the Grant of the Key Laboratory of Integrated Marine Monitoring and Applied Technologies for Harmful Algal Blooms,SOA(MATHAB)(No.MATHAB20100301)the Science and Technology Project of Shantou City,China(No.2011-162)
文摘The marine green alga Chaetomorpha valida fouls aquaculture ponds along the coastal cities of Dalian and Rongcheng, China. Unialgal cultures were observed under a microscope to determine the developmental morphological characters of C. valida. Results reveal that gametophytic filaments often produce lateral branches under laboratory culture conditions, suggesting an atypical heteromorphic life cycle of C. valida between unbranched sporophytes and branched gametophytes, which differs from typical isomorphic alternation of Chaetomorpha species. The shape of the basal attachment cell, an important taxonomic character within the genus, was found variable depending on environmental conditions. The 18S rDNA and 28S rDNA regions were used to explore the phylogenetic affinity of the taxa. Inferred trees from 18S rDNA sequences revealed a close relationship between C. valida and Chaetomorpha moniligera. These results would enrich information in general biology and morphological plasticity of C. valida and provided a basis for future identification of green tide forming algae.
文摘Meromictic lakes are interesting objects for study in terms of paleolimnology.The lamination of the bottom sediments well expressed in these lakes.It is related with permanent stratification of the water column.Through this
基金University Grants Commission (UGC) for funding to pursue this work
文摘This paper presents results from a statistical validation of the hindcasts of surface wind by a high-reso-ution-mesoscale atmospheric numerical model Advanced Research WRF （ARW3.3）, which is set up to force the operational coastal ocean forecast system at Indian Na- tional Centre for Ocean Information Services （INCOIS）. Evaluation is carried out based on comparisons of day-3 forecasts of surface wind with in situ and remote-sensing data. The results show that the model predicts the surface wind fields fairly accurately over the west coast of India, with high skill in predicting the surface wind during the pre-monsoon season. The model predicts the diurnal variability of the surface wind with reasonable accuracy. The model simulates the land-sea breeze cycle in the coastal region realistically, which is very clearly observed during the northeast monsoon and pre-monsoon season and is less prominent during the southwest monsoon season.
文摘In order to produce macromolecules by using the immobilized cells in microcapsules, a novel macro-porous NaCS-PDMDAAC capsules system was used to immobilize Candida valida in a semi-continuous culture mode for producing lipase. It was found that the encapsulation system had no negative effect on the growth and lipase productivity, and the lipase produced inside capsules could diffuse freely to the media outside capsules. The cultivation with the capsules was carried out for 15 batches and the lipase in each batch had almost the same activity. In comparison with free cell cultivation, the immobilized cell fermentation shortened obviously the period of glucose consumption from 24 hours to 8 hours and increased lipase productivity.
