In this study, some environmental factors were investigated to assess the potential effects on the dynamics of a dinoflagellate red tide caused by Gymnodinium catenatum in Shenhu Bay coastal waters in June, 2017. The ...In this study, some environmental factors were investigated to assess the potential effects on the dynamics of a dinoflagellate red tide caused by Gymnodinium catenatum in Shenhu Bay coastal waters in June, 2017. The highest cell density of G. catenatum was 1.0×10 6 cells/L, so it was known as the predominant species of the red tide discovered in Fujian coastal waters for the first time. Continuous rainfall process brought many land-based pollutants into the coastal waters, providing abundant nutrients for plankton growth. Then the continuous sunny and hot weather, high temperature, high salinity and south wind conditions accelerated the formation and occurrence of the red tide. During the red tide, DO, pH and COD increased remarkably and had significant positive correlations with the cell density of the red tide organisms. The contents of various nutrients decreased obviously, and eutrophication index E became low before and after the red tide, indicating the oligotrophic status of Shenhu Bay coastal waters. It is also found that DIP was one of the determinant environmental factors that induced the red tide. The N/P ratio of water in the declining phase of the red tide was close to the Redfield ratio. As for DIN, NH + 4-N and NO - 3-N were the two main species of inorganic nitrogen needed for this red tide dinoflagellate. The study indicates the relationship between the occurrence of the red tide and environmental conditions, providing essential reference for monitoring and forecasting research of red tide in marine environment and ecosystem management.展开更多
The indices related to sedimentary pyrite are widely used in paleo-environmental studies; however its application principles and flaws have not been presented in detail so far,therefore it is necessary to review the c...The indices related to sedimentary pyrite are widely used in paleo-environmental studies; however its application principles and flaws have not been presented in detail so far,therefore it is necessary to review the controlling factors of them. In this study the authors described the application principles in detail,including pyrite morphology,C/S ratio,DOP,size distribution,sulfur isotope,and further discussed the C-S-Fe system in oil shale in Meihe Formation which indicates oxic or suboxic conditions during oil shale deposition. The concentration of TOC and S in the oil shale in Meihe Formation is more than that in background mudstone,and the pyrite formation is limited by sulfate. Therefore studying the indices related to pyrite proves to be of great importance.展开更多
基金Supported by Key Laboratory of Integrated Marine Monitoring Technology and Applied Technologies for Harmful Algal Blooms,State Oceanic Administration(MATHAB201802)
文摘In this study, some environmental factors were investigated to assess the potential effects on the dynamics of a dinoflagellate red tide caused by Gymnodinium catenatum in Shenhu Bay coastal waters in June, 2017. The highest cell density of G. catenatum was 1.0×10 6 cells/L, so it was known as the predominant species of the red tide discovered in Fujian coastal waters for the first time. Continuous rainfall process brought many land-based pollutants into the coastal waters, providing abundant nutrients for plankton growth. Then the continuous sunny and hot weather, high temperature, high salinity and south wind conditions accelerated the formation and occurrence of the red tide. During the red tide, DO, pH and COD increased remarkably and had significant positive correlations with the cell density of the red tide organisms. The contents of various nutrients decreased obviously, and eutrophication index E became low before and after the red tide, indicating the oligotrophic status of Shenhu Bay coastal waters. It is also found that DIP was one of the determinant environmental factors that induced the red tide. The N/P ratio of water in the declining phase of the red tide was close to the Redfield ratio. As for DIN, NH + 4-N and NO - 3-N were the two main species of inorganic nitrogen needed for this red tide dinoflagellate. The study indicates the relationship between the occurrence of the red tide and environmental conditions, providing essential reference for monitoring and forecasting research of red tide in marine environment and ecosystem management.
文摘The indices related to sedimentary pyrite are widely used in paleo-environmental studies; however its application principles and flaws have not been presented in detail so far,therefore it is necessary to review the controlling factors of them. In this study the authors described the application principles in detail,including pyrite morphology,C/S ratio,DOP,size distribution,sulfur isotope,and further discussed the C-S-Fe system in oil shale in Meihe Formation which indicates oxic or suboxic conditions during oil shale deposition. The concentration of TOC and S in the oil shale in Meihe Formation is more than that in background mudstone,and the pyrite formation is limited by sulfate. Therefore studying the indices related to pyrite proves to be of great importance.
基金Sponsored by State Key Laboratory of Rare Earth Permanent Magnetic Materials(SKLREPM17OF06)National Natural Science Foundation of China(51871201)Key R&D Project of Zhejiang Provincial Department of Science and Technology(2021C01172)。