Ctenophore Pleurobrachia globosa(P.globosa)invades even the northernmost Bohai Sea from the south of China.Three years(2019-2021)of surveys were conducted in the Bohai Bay(BoB)of the Bohai Sea to examine its populatio...Ctenophore Pleurobrachia globosa(P.globosa)invades even the northernmost Bohai Sea from the south of China.Three years(2019-2021)of surveys were conducted in the Bohai Bay(BoB)of the Bohai Sea to examine its population dynamics and potential impact on nuclear power plants.Results show that P.globosa mainly occurred from July to October each year,reaching the maximum abundance in August/September and even bloomed in August 2020.Correlations with environmental factors indicate this species has strong tolerance to acidification and hypoxia,and it has potentially indirect feeding relationship with phytoplankton.Seven stages in three groups were illustrated in life history of P.globosa.Two entire generations were detected in August,confirming its 2-week generation time.Spawning time started earlier in the south than in the north of BoB.The spatiotemporal variation and life cycle of P.globosa in BoB are useful for further study on the invasion,bloom,aggregation,and regeneration of P.globosa.展开更多
[Objective] This study was to analyze the several nutrient elements de- manded for the growth of Wolffia globosa with the aim to provide references for the improvement on the formula of nutrient solution for the culti...[Objective] This study was to analyze the several nutrient elements de- manded for the growth of Wolffia globosa with the aim to provide references for the improvement on the formula of nutrient solution for the cultivation of Wolffia globosa. [Method] The basic conditions of the pond were simulated in the greenhouse, and nutrient solution was added to cultivate Wolffia globosa. The main element composi- tions of the experimental water, wild water and dried Wolffia globosa were detected by inductively coupled plasma spectrometer （ICP） and element analyzer, in order to study the nutrient demand for Wolffia globosa growth. And the absorption of N, P, K and consumption of P for the growth of Wolffia globosa were also analyzed. [Re- suit] The Wolffia globosa biomass of the experimental group which cultivated by adding nutrient solution increased over time, and after 2 weeks, the average capacity was significantly more than initial capacity; and the average capacity of the control group without nutrient solution was significantly lower than initial capacity, indicating that the addition of nutrient solution has obvious effect on the growth of Wolffia glo- bosa. However, the biomass of the experimental group was no longer increase after 2 weeks, indicating that there are some inhibitory factors in the incubators of the experimental group. The element detection results were as follows： the content pro- portions of N, P and K were 3.8：1：2.8, 11.5：1：17 and 5.2：1：6.8 in the experimental water, wild water and drying Wolffia globosa, respectively. The N, P, K in the water of experimental group was not exhausted, while the contents of Ca and Zn in three experimental incubators were below the limit of detection （ND）. And the contents of Mn in incubators No.l-No.3 were ND, 0.05 and 0.38 mg/L, respectively, presenting positive correlation with the biomass of Wolffia globosa. The inhibitory growth of Wolffia globosa is closely related with the absence of Ca, Mn and Zn in the nutrient solution. [Conclusion] The experimental results provided valuable parameters for the improvement on the formula of the original nutrient solution.展开更多
The colony-forming Phaeocystis species are causative agents of dense bloom occurrences incoastal waters worldwide. It is difficult to separate them because of the different morphologies associated with their colonial ...The colony-forming Phaeocystis species are causative agents of dense bloom occurrences incoastal waters worldwide. It is difficult to separate them because of the different morphologies associated with their colonial stages. In this study we applied molecular approaches to analyze the genetic variation of Phaeocystis globosa and Phaeocystis pouchetii from several geographic regions, and to assist in tracing the dispersal of bloom-forming Phaeocystis species in coastal waters of China. The sequences of the internal transcribed spacers (ITS1 and ITS2) of rDNA and the 5. 8S ribosomal RNA gene of Phaeocystis strains were determined. Sequence comparison shows that P.globosa was the most divergent to P. pouchetii, exhibiting sequence divergence higher than 0.08. However, lower genetic divergences existed between strains of P. globosa. The sequence comparison of the Phaeocystis rDNA ITS clearly shows that the species isolated from the southeast coast of China is identified as P. globosa rather than P. cf. pouchetii or other species. Furthermore, the significance of rDNA variation in distinct global populations of P. globosa suggested it might have had sufficient time to accumulate detectable mutations at the rDNA locus, supporting the hypothesis of ancient dispersal of P .globosa to many areas, meaning that P. globosa blooms in the coastal waters of China are endemic rather than a newly introduced species or a foreign source. Finally, based on the high divergent region of rDNA ITS, a pair of species-specific primers for P. globosa were designed, they could be useful to detect the presence of this species in mixed plankton assemblages or flagellate stages that are recognized with diffculties by means of conventional microscopy.展开更多
Blooms of Phaeocystis globosa have been frequently reported in Chinese coastal waters, causing serious damage to marine ecosystems. To better understand the ecological characteristics of P. globosa in Chinese coastal ...Blooms of Phaeocystis globosa have been frequently reported in Chinese coastal waters, causing serious damage to marine ecosystems. To better understand the ecological characteristics of P. globosa in Chinese coastal waters that facilitate its rapid expansion, the effects of temperature, salinity and irradiance on the growth of P. globosa from the South China Sea were examined in the laboratory. The saturating irradiance for the growth ofP. globosa （Is） was 60 μmol/（m^2·s）, which was lower than those of other harmful algal species （70-114μmol/（m^2·s））. A moderate growth rate of 0.22/d was observed at 2 μmol/（m^2·s） （the minimum irradiance in the experiment）, and photo-inhibition did not occur at 230 μmol/（m^2·s） （the maximum irradiance in the experiment）. Exposed to 42 different combinations of temperatures （10- 31 ℃） and salinities （10-40） under saturating irradiance, P. globosa exhibited its maximum specific growth rate of 0.80/d at the combinations of 24℃ and 35, and 27℃ and 40. The optimum growth rates （〉0.80/d） were observed at temperatures ranging from 24 to 27℃ and salinities from 35 to 40. While P. globosa was able to grow well at temperatures from 20℃ to 31℃ and salinities from 20 to 40, it could not grow at temperatures lower than 15℃ or salinities lower than 15. Factorial analysis revealed that temperature and salinity has similar influences on the growth of this species. This strain ofP. globosa not only prefers higher temperatures and higher salinity, but also possesses a flexible nutrient competing strategy, adapted to lower irradiance. Therefore, the P. globosa population from South China Sea should belong to a new ecotype. There is also a potentially high risk of blooms developing in this area throughout the year.展开更多
Phaeocystis globosa Scherffel is one of the common harmful algae species in coastal waters of the southeastern China.In this study,sandwich hybridization integrated with nuclease protection assay(NPA-SH)was used to qu...Phaeocystis globosa Scherffel is one of the common harmful algae species in coastal waters of the southeastern China.In this study,sandwich hybridization integrated with nuclease protection assay(NPA-SH)was used to qualitatively and quantitatively detect P. globosa.Results showed that this method had good applicability and validity in analyzing the samples from laboratory cultures and from fields.The linear regression equation for P.globosa was obtained,and the lowest detection number of cells was 1.8×104 c...展开更多
基金Supported by the National Key Research and Development Program of China(No.2018 YFC 1407501)the State Key Laboratory of Estuarine and Coastal Zone Environment for Environmental Protection,Chinese Research Academy of Environmental Sciences(No.HKHA 2022004)。
文摘Ctenophore Pleurobrachia globosa(P.globosa)invades even the northernmost Bohai Sea from the south of China.Three years(2019-2021)of surveys were conducted in the Bohai Bay(BoB)of the Bohai Sea to examine its population dynamics and potential impact on nuclear power plants.Results show that P.globosa mainly occurred from July to October each year,reaching the maximum abundance in August/September and even bloomed in August 2020.Correlations with environmental factors indicate this species has strong tolerance to acidification and hypoxia,and it has potentially indirect feeding relationship with phytoplankton.Seven stages in three groups were illustrated in life history of P.globosa.Two entire generations were detected in August,confirming its 2-week generation time.Spawning time started earlier in the south than in the north of BoB.The spatiotemporal variation and life cycle of P.globosa in BoB are useful for further study on the invasion,bloom,aggregation,and regeneration of P.globosa.
基金Supported by the Forestry Industry Public Welfare Project of State Forestry Bureau(200904001)the National Natural Science Foundation of China(NSFC J0730641)~~
文摘[Objective] This study was to analyze the several nutrient elements de- manded for the growth of Wolffia globosa with the aim to provide references for the improvement on the formula of nutrient solution for the cultivation of Wolffia globosa. [Method] The basic conditions of the pond were simulated in the greenhouse, and nutrient solution was added to cultivate Wolffia globosa. The main element composi- tions of the experimental water, wild water and dried Wolffia globosa were detected by inductively coupled plasma spectrometer （ICP） and element analyzer, in order to study the nutrient demand for Wolffia globosa growth. And the absorption of N, P, K and consumption of P for the growth of Wolffia globosa were also analyzed. [Re- suit] The Wolffia globosa biomass of the experimental group which cultivated by adding nutrient solution increased over time, and after 2 weeks, the average capacity was significantly more than initial capacity; and the average capacity of the control group without nutrient solution was significantly lower than initial capacity, indicating that the addition of nutrient solution has obvious effect on the growth of Wolffia glo- bosa. However, the biomass of the experimental group was no longer increase after 2 weeks, indicating that there are some inhibitory factors in the incubators of the experimental group. The element detection results were as follows： the content pro- portions of N, P and K were 3.8：1：2.8, 11.5：1：17 and 5.2：1：6.8 in the experimental water, wild water and drying Wolffia globosa, respectively. The N, P, K in the water of experimental group was not exhausted, while the contents of Ca and Zn in three experimental incubators were below the limit of detection （ND）. And the contents of Mn in incubators No.l-No.3 were ND, 0.05 and 0.38 mg/L, respectively, presenting positive correlation with the biomass of Wolffia globosa. The inhibitory growth of Wolffia globosa is closely related with the absence of Ca, Mn and Zn in the nutrient solution. [Conclusion] The experimental results provided valuable parameters for the improvement on the formula of the original nutrient solution.
基金This study was supported by the National Natural Science Foundation of China under contract No. 39970063the Natural Science Foundation of Guangdong Province, China under contract No. 001213the Red-tide Key Project of the Natural Science Foundatio
文摘The colony-forming Phaeocystis species are causative agents of dense bloom occurrences incoastal waters worldwide. It is difficult to separate them because of the different morphologies associated with their colonial stages. In this study we applied molecular approaches to analyze the genetic variation of Phaeocystis globosa and Phaeocystis pouchetii from several geographic regions, and to assist in tracing the dispersal of bloom-forming Phaeocystis species in coastal waters of China. The sequences of the internal transcribed spacers (ITS1 and ITS2) of rDNA and the 5. 8S ribosomal RNA gene of Phaeocystis strains were determined. Sequence comparison shows that P.globosa was the most divergent to P. pouchetii, exhibiting sequence divergence higher than 0.08. However, lower genetic divergences existed between strains of P. globosa. The sequence comparison of the Phaeocystis rDNA ITS clearly shows that the species isolated from the southeast coast of China is identified as P. globosa rather than P. cf. pouchetii or other species. Furthermore, the significance of rDNA variation in distinct global populations of P. globosa suggested it might have had sufficient time to accumulate detectable mutations at the rDNA locus, supporting the hypothesis of ancient dispersal of P .globosa to many areas, meaning that P. globosa blooms in the coastal waters of China are endemic rather than a newly introduced species or a foreign source. Finally, based on the high divergent region of rDNA ITS, a pair of species-specific primers for P. globosa were designed, they could be useful to detect the presence of this species in mixed plankton assemblages or flagellate stages that are recognized with diffculties by means of conventional microscopy.
基金Supported by the National Natural Science Foundation of China(NSFC)(Nos.41576159,U1133003)the National High Technology Research and Development Program of China(863 Program)(No.2013AA065805)
文摘Blooms of Phaeocystis globosa have been frequently reported in Chinese coastal waters, causing serious damage to marine ecosystems. To better understand the ecological characteristics of P. globosa in Chinese coastal waters that facilitate its rapid expansion, the effects of temperature, salinity and irradiance on the growth of P. globosa from the South China Sea were examined in the laboratory. The saturating irradiance for the growth ofP. globosa （Is） was 60 μmol/（m^2·s）, which was lower than those of other harmful algal species （70-114μmol/（m^2·s））. A moderate growth rate of 0.22/d was observed at 2 μmol/（m^2·s） （the minimum irradiance in the experiment）, and photo-inhibition did not occur at 230 μmol/（m^2·s） （the maximum irradiance in the experiment）. Exposed to 42 different combinations of temperatures （10- 31 ℃） and salinities （10-40） under saturating irradiance, P. globosa exhibited its maximum specific growth rate of 0.80/d at the combinations of 24℃ and 35, and 27℃ and 40. The optimum growth rates （〉0.80/d） were observed at temperatures ranging from 24 to 27℃ and salinities from 35 to 40. While P. globosa was able to grow well at temperatures from 20℃ to 31℃ and salinities from 20 to 40, it could not grow at temperatures lower than 15℃ or salinities lower than 15. Factorial analysis revealed that temperature and salinity has similar influences on the growth of this species. This strain ofP. globosa not only prefers higher temperatures and higher salinity, but also possesses a flexible nutrient competing strategy, adapted to lower irradiance. Therefore, the P. globosa population from South China Sea should belong to a new ecotype. There is also a potentially high risk of blooms developing in this area throughout the year.
基金supported by the National Hi-Tech Research and Development Program(863)of China(No.2006AA09Z178,2001AA635090)the National Nat-ural Science Foundation of China(No.40706044)
文摘Phaeocystis globosa Scherffel is one of the common harmful algae species in coastal waters of the southeastern China.In this study,sandwich hybridization integrated with nuclease protection assay(NPA-SH)was used to qualitatively and quantitatively detect P. globosa.Results showed that this method had good applicability and validity in analyzing the samples from laboratory cultures and from fields.The linear regression equation for P.globosa was obtained,and the lowest detection number of cells was 1.8×104 c...
