Two cruises were conducted to study the composition and seasonal variation of tintinnids （Protozoa： Ciliata） in Shantou coast water dudng spring and fall. Remarkable seasonal variations in environmental parameters,...Two cruises were conducted to study the composition and seasonal variation of tintinnids （Protozoa： Ciliata） in Shantou coast water dudng spring and fall. Remarkable seasonal variations in environmental parameters, and tintinnids composition were observed. Tintinnids samples were enumerated and identified from 5 stations. 14 species belonging to 7 genuses of tintinnids were identified, and the dominate species was Leprotintinnus simple in these season. High tintinnids diversity and low abundance occurred in the fall, and on the contrary, low tintinnids diversity and high abundance occurred in the spring. No significant correlation occurred between tintinnids abundance and nutrients. Tintinnids abundance showed negative relationship with salinity （r2=0.63, P 〈 0.05）, maybe this was due to the cold raised water carried sum nutrients rise to the surface water in the fall, rich nutrients and high phytoplankton biomass decrease the importance of tintinnids in the energy flow of aquatic food web.展开更多
Tintinnids were enumerated and identified in samples collected from 36 stations between 18°-22°N, 107°-122 °E in the northern South China Sea （NSCS）. 44 species belonging to 24 genera of tintinni...Tintinnids were enumerated and identified in samples collected from 36 stations between 18°-22°N, 107°-122 °E in the northern South China Sea （NSCS）. 44 species belonging to 24 genera of tintinnids were recorded. The dominant species were He/icostome/la /onga and Tintinnopsis radix. Tintinnids abundance ranged from 0 to 2 200 cell/L, and mean abundance was 221cell/L in the surface water. Tintinnids abundance and species numbers decreased from coast to offshore. Upwelling and Pearl River discharge influenced the distribution of tintinnids by regulating nutrients supply. Maximum abundance （2 200 cell/L） was found in the surface water of A1. Tintinnids abundance showed positive relationship with chlorophyll a （Chl a） concentration, and no significant relationship was found between tintinnids abundance and temperature.展开更多
The influence of sea ice on the species composition and cell density of phytoplankton was investigated in the eastern Bering Sea in spring 2008. Diatoms, particularly pennate diatoms, dominated the phytoplankton commu...The influence of sea ice on the species composition and cell density of phytoplankton was investigated in the eastern Bering Sea in spring 2008. Diatoms, particularly pennate diatoms, dominated the phytoplankton community. The dominant species were Grammonema islandica （Grunow in Van Heurck） Hasle, Fragilariopsis cylindrus （Grunow） Krieger, F. oceanica （Cleve） Hasle, Navicula vanhoeffenii Gran, Thalassiosira antarctica Comber, T. gravida Cleve, T. nordenskioeldii Cleve, and T. rotula Meunier. Phytoplankton cell densities varied from 0.08× 10^4 to 428.8× 10^4 cells/L, with an average of 30.3× 10^4 cells/L. Using cluster analysis, phytoplankton were grouped into three assemblages defined by ice-forming conditions： open wate.r, ice edge, and sea ice assemblages. In spring, when the sea ice melts, the phytoplankton dispersed from the sea ice to the ice edge and even into open waters. Thus, these phytoplankton in the sea ice may serve as a “seed bank” for phytoplankton population succession in the subarctic ecosystem. Moreover, historical studies combined with these results suggest that the sizes of diatom species have become smaller, shifting from microplankton to nannoplankton-dominated communities.展开更多
To examine the importance of kin selection in shaping human societies, this study analyzed the kinship system practiced in traditional China for two millennia and teased apart its underlying genetic and other, presuma...To examine the importance of kin selection in shaping human societies, this study analyzed the kinship system practiced in traditional China for two millennia and teased apart its underlying genetic and other, presumably cultural, components. The results demonstrate that, in the traditional patrilineal Chinese family, both genetic relatedness and the cultural factor of generation were important in determining kinship status for male agnates （genetically related relatives）. For female agnates, however, only genetic relatedness was important. Another surprising finding was that the influence of gender was not as important as genetic relatedness. The most interesting finding in this study, however, was that kin selection and culture （i.e., seniority in generation and age） played vastly different roles in different lineages in the Chinese family： for collateral （indirect） agnates, genetic relatedness was the most important factor in determining their kinship status, but for lineal （direct） agnates, its importance was overridden by seniority in generation and age, a cultural factor. Several other bio-cultural factors also explained a considerable amount of variance in kinship status. Since kinship profoundly affected, and was often the foundation of, the legal and social systems in dynastic China, kin selection, while its strength may differ remarkably between lineal and collateral relatives, could act as a selective force in Chinese families展开更多
基金support of this study was provided by the National Science Committee through Grants NSC U0633007,40576052
文摘Two cruises were conducted to study the composition and seasonal variation of tintinnids （Protozoa： Ciliata） in Shantou coast water dudng spring and fall. Remarkable seasonal variations in environmental parameters, and tintinnids composition were observed. Tintinnids samples were enumerated and identified from 5 stations. 14 species belonging to 7 genuses of tintinnids were identified, and the dominate species was Leprotintinnus simple in these season. High tintinnids diversity and low abundance occurred in the fall, and on the contrary, low tintinnids diversity and high abundance occurred in the spring. No significant correlation occurred between tintinnids abundance and nutrients. Tintinnids abundance showed negative relationship with salinity （r2=0.63, P 〈 0.05）, maybe this was due to the cold raised water carried sum nutrients rise to the surface water in the fall, rich nutrients and high phytoplankton biomass decrease the importance of tintinnids in the energy flow of aquatic food web.
基金support for this study was provided by the National Science Committee through Grants NSC 40531006, U0633007, 40576052
文摘Tintinnids were enumerated and identified in samples collected from 36 stations between 18°-22°N, 107°-122 °E in the northern South China Sea （NSCS）. 44 species belonging to 24 genera of tintinnids were recorded. The dominant species were He/icostome/la /onga and Tintinnopsis radix. Tintinnids abundance ranged from 0 to 2 200 cell/L, and mean abundance was 221cell/L in the surface water. Tintinnids abundance and species numbers decreased from coast to offshore. Upwelling and Pearl River discharge influenced the distribution of tintinnids by regulating nutrients supply. Maximum abundance （2 200 cell/L） was found in the surface water of A1. Tintinnids abundance showed positive relationship with chlorophyll a （Chl a） concentration, and no significant relationship was found between tintinnids abundance and temperature.
基金Supported by the National Natural Science Foundation of China(Nos.41276128,41476116)the National Basic Research Program of China(973 Program)(No.2010CB428704)
文摘The influence of sea ice on the species composition and cell density of phytoplankton was investigated in the eastern Bering Sea in spring 2008. Diatoms, particularly pennate diatoms, dominated the phytoplankton community. The dominant species were Grammonema islandica （Grunow in Van Heurck） Hasle, Fragilariopsis cylindrus （Grunow） Krieger, F. oceanica （Cleve） Hasle, Navicula vanhoeffenii Gran, Thalassiosira antarctica Comber, T. gravida Cleve, T. nordenskioeldii Cleve, and T. rotula Meunier. Phytoplankton cell densities varied from 0.08× 10^4 to 428.8× 10^4 cells/L, with an average of 30.3× 10^4 cells/L. Using cluster analysis, phytoplankton were grouped into three assemblages defined by ice-forming conditions： open wate.r, ice edge, and sea ice assemblages. In spring, when the sea ice melts, the phytoplankton dispersed from the sea ice to the ice edge and even into open waters. Thus, these phytoplankton in the sea ice may serve as a “seed bank” for phytoplankton population succession in the subarctic ecosystem. Moreover, historical studies combined with these results suggest that the sizes of diatom species have become smaller, shifting from microplankton to nannoplankton-dominated communities.
文摘To examine the importance of kin selection in shaping human societies, this study analyzed the kinship system practiced in traditional China for two millennia and teased apart its underlying genetic and other, presumably cultural, components. The results demonstrate that, in the traditional patrilineal Chinese family, both genetic relatedness and the cultural factor of generation were important in determining kinship status for male agnates （genetically related relatives）. For female agnates, however, only genetic relatedness was important. Another surprising finding was that the influence of gender was not as important as genetic relatedness. The most interesting finding in this study, however, was that kin selection and culture （i.e., seniority in generation and age） played vastly different roles in different lineages in the Chinese family： for collateral （indirect） agnates, genetic relatedness was the most important factor in determining their kinship status, but for lineal （direct） agnates, its importance was overridden by seniority in generation and age, a cultural factor. Several other bio-cultural factors also explained a considerable amount of variance in kinship status. Since kinship profoundly affected, and was often the foundation of, the legal and social systems in dynastic China, kin selection, while its strength may differ remarkably between lineal and collateral relatives, could act as a selective force in Chinese families
