Based on the field survey data of four cruises in 2011,all phytoplankton communities in the southern Yellow Sea (SYS) were investigated for the species composition,dominant species,abundance and diversity indices.A to...Based on the field survey data of four cruises in 2011,all phytoplankton communities in the southern Yellow Sea (SYS) were investigated for the species composition,dominant species,abundance and diversity indices.A total of 379 species belonging to9 phyla were identified,of which the most abundant group was Bacillariophyta (60.9%) ,followed by Pyrrophyta (23.7%) and Haptophyta (6.9%) .The seasonal distribution of abundance was:summer (4137.1×103ind m 3) >spring (3940.4×103ind m 3) >winter (3010.6×103ind m 3) >autumn (340.8×103ind m 3) ,while the horizontal distribution showed a decreasing tendency from inshore to offshore regions.The dominant species of phytoplankton varied in different seasons.The dominant species were Thalassiosira pacifica,Skeletoema spp.and Chaetoceros cinctus in spring,Chaetoceros debbilis,Chaetoceros pseudocurvisetus and Chaetoceros curvisetus in summer,Thalassiosira curviseriata,Alexandrium catenella and Ceratium fusus in autumn,Paralia sulcata,Phaeocystis sp.and Bacillaria paradoxa in winter,respectively.In SYS,the group of temperate coastal species was the major ecotype,and the groups of the central SYS species and oceanic species were also important constituents.The average values of Shannon-Weaver diversity index (H’) and Pielou evenness index (J) were 2.37 and 0.65 respectively.The indices H’and J in the open sea were higher than those in coastal waters.Obvious co-variation tendencies between H’and J were observed in all but the summer cruise of this survey.展开更多
With the rapid development of economy and increase of population in the drainage areas,the nutrient loading has increased dramatically in the Changjiang estuary and adjacent coastal waters.To properly assess the impac...With the rapid development of economy and increase of population in the drainage areas,the nutrient loading has increased dramatically in the Changjiang estuary and adjacent coastal waters.To properly assess the impact of nutrient enrichment on phytoplankton community,seasonal microcosm experiments were conducted during August 2010 July 2011 in the coastal waters of Zhejiang Province.The results of the present study indicated that the chl a concentration,cell abundance,diversity indices,species composition and community succession of the phytoplankton varied significantly with different N/P ratios and seasons.Higher growth was observed in the 64:1(spring),32:1(summer),16:1(autumn)and 128:1,256:1(winter)treatments,respectively.The values of Shannon-Wiener index(H′)and Pielou evenness index(J)were lower in the 8:1 and 16:1 treatments in autumn test,while H'value was higher in the 128:1 and 8:1 treatments in winter test.A definite community succession order from diatoms to dinoflagellates was observed in the autumn and winter tests,while the diatoms dominated the community throughout the culture in the spring and summer tests.展开更多
To find out the decay character of residual chlorine （RC） in the sea water, the concentration of RC was analyzed by N, N-diethyl-p-phenylenediamine （DPD） method under different simulation experimental conditions, ...To find out the decay character of residual chlorine （RC） in the sea water, the concentration of RC was analyzed by N, N-diethyl-p-phenylenediamine （DPD） method under different simulation experimental conditions, in which salinity, temperature, and Chemical Oxygen Demand （COD） were selected. The water used in the experiment was the mixture of aging ocean water, coastal water and extracting solution of coastal sediment at appropriate level. Results are shown as follows： （1） Piecewise function can well reflect the decay dynamics of RC in the cooling seawater. Concretely, the decay dynamics of first 1 min is too rapid to ascertain using a specific kinetic function, and that of the time from 1 to 30 min is fit for the first-order kinetic model. （2） The results could be the foundation of the chemical behavior of RC in seawater, and be used as not only the guidance of the coastal power plants production and sea water desalting companies, but also the establishment of the correlative trade standard.展开更多
The distributions of N utilizing bacteria (denitrifying bacteria and ammonifying bacteria) ,P utilizing bacteria (organic phosphobacteria and inorganic phosphobacteria) and heterotrophic bacteria in the Changjiang Est...The distributions of N utilizing bacteria (denitrifying bacteria and ammonifying bacteria) ,P utilizing bacteria (organic phosphobacteria and inorganic phosphobacteria) and heterotrophic bacteria in the Changjiang Estuary,and the roles of main environmental factors in distributing bacteria,are explored with observations from two cruises in June and August 2006.Comparisons between the two important periods of initial hypoxia phase (June) and developed hypoxia phase (August) show differences in both bacterial distributions and the associated main environmental factors.First,the primary group of ammonifying bacteria has larger magnitude with spatial maximum value in the hypoxic stations related to sediment in August.The phosphobacterial abundance and detection rates in August are much lower than those in June,but the denitrifying bacterial abundance becomes greater in August.However,the difference of heterotrophic bacterial abundance between June and August is not obvious.Second,main environmental factors influencing bacteria vary from initial hypoxia phase to developed hypoxia phase.Two parameters (salinity and NO3) in surface water and five environmental parameters (pH,salinity,PO43,NO3and temperature) in bottom water and surface sediment play major roles in the bacterial abundance in June,while different parameter combinations (salinity and PO43) in surface water and different parameter combinations (DO,DOC,NO3,PO43 and pH) in bottom water and surface sediment play major roles in August.Moreover,the bottom bacteria distributions in area south of 31 N are related to the position of the Taiwan Warm Current in June.The bacterial abundance and distribution may respond to the environmental change in the hypoxia processes of initial phase and developed phase.During the hypoxia processes,the whole structure of bacterial functional groups probably turns to different states,causing the recycling of nutrient regeneration and aggravating hypoxia regionally.展开更多
Shelf seas are important systems supporting China’s rapid economic and societal developments.However,the Yellow Sea(YS)and the East China Sea(ECS)environments have undergone dramatic changes recently,which have profo...Shelf seas are important systems supporting China’s rapid economic and societal developments.However,the Yellow Sea(YS)and the East China Sea(ECS)environments have undergone dramatic changes recently,which have profoundly impacted their ecosystem health.Being within the Asian monsoon-dominated region,the environment of the YS and the ECS is influenced by oceanic processes such as the intrusion of the Kuroshio Current(KC)and by human activities of China’s rapidly developed coastal regions.Thus,the YS and the ECS are ideal regions to understand and to distinguish the influences展开更多
基金supported by the grants from the National Basic Research Program of China(No.2010CB428903)the National Marine Public Welfare Research Project of China(Nos.201205015 and 201305009)+5 种基金the National Natural Science Foundation of China(No.41206103)the Basic Scientific Research of SIO,SOA(No.JG1222)the National Natural Science Foundation of China(No.41306112)the Zhejiang Provincial Natural Science Foundation(No.LY13D060004)the Basic Scientific Research Fund of SIO,China(No.JG1311)the Marine Science Foundation of State Oceanic Administration for Youth(No.2013140)
文摘Based on the field survey data of four cruises in 2011,all phytoplankton communities in the southern Yellow Sea (SYS) were investigated for the species composition,dominant species,abundance and diversity indices.A total of 379 species belonging to9 phyla were identified,of which the most abundant group was Bacillariophyta (60.9%) ,followed by Pyrrophyta (23.7%) and Haptophyta (6.9%) .The seasonal distribution of abundance was:summer (4137.1×103ind m 3) >spring (3940.4×103ind m 3) >winter (3010.6×103ind m 3) >autumn (340.8×103ind m 3) ,while the horizontal distribution showed a decreasing tendency from inshore to offshore regions.The dominant species of phytoplankton varied in different seasons.The dominant species were Thalassiosira pacifica,Skeletoema spp.and Chaetoceros cinctus in spring,Chaetoceros debbilis,Chaetoceros pseudocurvisetus and Chaetoceros curvisetus in summer,Thalassiosira curviseriata,Alexandrium catenella and Ceratium fusus in autumn,Paralia sulcata,Phaeocystis sp.and Bacillaria paradoxa in winter,respectively.In SYS,the group of temperate coastal species was the major ecotype,and the groups of the central SYS species and oceanic species were also important constituents.The average values of Shannon-Weaver diversity index (H’) and Pielou evenness index (J) were 2.37 and 0.65 respectively.The indices H’and J in the open sea were higher than those in coastal waters.Obvious co-variation tendencies between H’and J were observed in all but the summer cruise of this survey.
基金supported by the Ministry of Science and Technology of P.R.China under grant contracts (No.2010CB428903)the National Natural Science Foundation of China (No.41306112)+3 种基金the National Marine Public Welfare Research Project of China (Nos.201305043,200805069)the Zhejiang Provincial Natural Science Foundation (Nos.LY13D060004,Y5110131)the Marine Science Foundation of State Oceanic Administration for Youth (Nos.2013140,2013144)the Basic Scientific Research Fund of SIO,China (Nos.JG1311,JG1221)
文摘With the rapid development of economy and increase of population in the drainage areas,the nutrient loading has increased dramatically in the Changjiang estuary and adjacent coastal waters.To properly assess the impact of nutrient enrichment on phytoplankton community,seasonal microcosm experiments were conducted during August 2010 July 2011 in the coastal waters of Zhejiang Province.The results of the present study indicated that the chl a concentration,cell abundance,diversity indices,species composition and community succession of the phytoplankton varied significantly with different N/P ratios and seasons.Higher growth was observed in the 64:1(spring),32:1(summer),16:1(autumn)and 128:1,256:1(winter)treatments,respectively.The values of Shannon-Wiener index(H′)and Pielou evenness index(J)were lower in the 8:1 and 16:1 treatments in autumn test,while H'value was higher in the 128:1 and 8:1 treatments in winter test.A definite community succession order from diatoms to dinoflagellates was observed in the autumn and winter tests,while the diatoms dominated the community throughout the culture in the spring and summer tests.
基金The Foundation of Program on Research for Public Good of MOST of China under contract No2004DIB3J087the Youth Foundation of Marine Science of State Oceanic Administration of China under contract No 2005106the Provincial Natural Science Foundation of Zhejiang, China under contract No Y504012
文摘To find out the decay character of residual chlorine （RC） in the sea water, the concentration of RC was analyzed by N, N-diethyl-p-phenylenediamine （DPD） method under different simulation experimental conditions, in which salinity, temperature, and Chemical Oxygen Demand （COD） were selected. The water used in the experiment was the mixture of aging ocean water, coastal water and extracting solution of coastal sediment at appropriate level. Results are shown as follows： （1） Piecewise function can well reflect the decay dynamics of RC in the cooling seawater. Concretely, the decay dynamics of first 1 min is too rapid to ascertain using a specific kinetic function, and that of the time from 1 to 30 min is fit for the first-order kinetic model. （2） The results could be the foundation of the chemical behavior of RC in seawater, and be used as not only the guidance of the coastal power plants production and sea water desalting companies, but also the establishment of the correlative trade standard.
基金supported by the National Basic Research Program of China(2010CB428903)the Chinese offshore Investigation and Assessment Program(908-01-BC06)+5 种基金the National Marine Public Welfare Research Project of China(201305043-3)the Innovative Team of Key Science and Technology on Marine Aquaculture of Zhejiang Province(2010R50025)the Marine Science Foundation of State Oceanic Administration for Youth(2013140)the National Natural Science Foundation of China(41306112)the Zhejiang Provincial Natural Science Foundation(LY13D060004)the Basic Scientific Research Fundof SIO,China(JG1 311,JG1312)
文摘The distributions of N utilizing bacteria (denitrifying bacteria and ammonifying bacteria) ,P utilizing bacteria (organic phosphobacteria and inorganic phosphobacteria) and heterotrophic bacteria in the Changjiang Estuary,and the roles of main environmental factors in distributing bacteria,are explored with observations from two cruises in June and August 2006.Comparisons between the two important periods of initial hypoxia phase (June) and developed hypoxia phase (August) show differences in both bacterial distributions and the associated main environmental factors.First,the primary group of ammonifying bacteria has larger magnitude with spatial maximum value in the hypoxic stations related to sediment in August.The phosphobacterial abundance and detection rates in August are much lower than those in June,but the denitrifying bacterial abundance becomes greater in August.However,the difference of heterotrophic bacterial abundance between June and August is not obvious.Second,main environmental factors influencing bacteria vary from initial hypoxia phase to developed hypoxia phase.Two parameters (salinity and NO3) in surface water and five environmental parameters (pH,salinity,PO43,NO3and temperature) in bottom water and surface sediment play major roles in the bacterial abundance in June,while different parameter combinations (salinity and PO43) in surface water and different parameter combinations (DO,DOC,NO3,PO43 and pH) in bottom water and surface sediment play major roles in August.Moreover,the bottom bacteria distributions in area south of 31 N are related to the position of the Taiwan Warm Current in June.The bacterial abundance and distribution may respond to the environmental change in the hypoxia processes of initial phase and developed phase.During the hypoxia processes,the whole structure of bacterial functional groups probably turns to different states,causing the recycling of nutrient regeneration and aggravating hypoxia regionally.
文摘Shelf seas are important systems supporting China’s rapid economic and societal developments.However,the Yellow Sea(YS)and the East China Sea(ECS)environments have undergone dramatic changes recently,which have profoundly impacted their ecosystem health.Being within the Asian monsoon-dominated region,the environment of the YS and the ECS is influenced by oceanic processes such as the intrusion of the Kuroshio Current(KC)and by human activities of China’s rapidly developed coastal regions.Thus,the YS and the ECS are ideal regions to understand and to distinguish the influences
