DOI QR코드

DOI QR Code

Analysis of Environmental Factors Related to Seasonal Variation of Bacteria and Heterotrophic Nanoflagellate in Kyeonggi Bay, Korea

경기만에서 박테리아와 종속영양편모류의 계절변화에 미치는 환경요인 분석

  • Baek, Seung Ho (Korea Institute of Ocean Science and Technology (KIOST) /South Sea Institue) ;
  • You, Kai (Fisheries College, Ocean University of China) ;
  • Han, Myung-Soo (Department of Life Science, Hanyang University)
  • 백승호 (한국해양과학기술원 남해연구소) ;
  • 유카이 (중국해양대학교 수산학부) ;
  • 한명수 (한양대학교 생명과학과)
  • Received : 2017.05.22
  • Accepted : 2017.06.13
  • Published : 2017.06.30

Abstract

From June 2007 to May 2008, seasonal variations of bacterial abundance and heterotrophic nanoflagellate (HNF), together with environmental factors, were investigated at weekly and monthly intervals in Kyeonggi Bay. During the study period, the water temperature and salinity varied from $1.9^{\circ}C{\sim}29.0^{\circ}C$ and 31~35.1 psu, respectively. The concentration of ammonia, nitrate+nitrite, phosphate, and silicate ranged from 0.01 to $3.22{\mu}M$, 2.03 to $15.34{\mu}M$, 0.06 to $1.82{\mu}M$, and 0.03 to $18.3{\mu}M$, respectively. The annual average concentration of Chl. a varied from $0.86{\mu}g\;L^{-1}$ to $37.70{\mu}g\;L^{-1}$; the concentration was twice as much at the surface than at the deeper layers. The abundance of bacteria and HNF ranged from $0.29{\times}10^6$ to $7.62{\times}10^6cells\;mL^{-1}$ and $1.00{\times}10^2$ to $1.26{\times}10^3cells\;mL^{-1}$, respectively. In particular, there were significant correlations between bacteria and HNF abundance (p<0.05), and then the high abundance of HNF was frequently observed with an increase of bacterial abundance in summer (p<0.001). Our results therefore indicate that bacterial abundance in the bay was mainly controlled by resources supplied as organic and inorganic substances from Lake Shihwa due to the daily water exchange after dike construction. Also, the bacterial abundance was significantly controlled by HNF grazing pressure (top-down) in the warm seasons, i.e. excluding winter, in the Kyeonggi Bay.

수환경요인이 미소생물 그룹 박테리아와 종속영양편모류의 계절적 분포에 미치는 영향을 파악하기 위해서 2007년 6월에서 2008월 5월 사이에 경기만에서 그들의 동태 및 환경요인을 조사하였다. 조사기간 동안 수온과 염분은 $1.9^{\circ}C{\sim}29.0^{\circ}C$와 31~35.1 psu로 변화하였으며, 하계에 현저한 수온 증가와 함께 표층 염분이 상대적으로 낮게 관찰되었다. 영양염 중 암모니아의 농도는 $0.01{\sim}3.22{\mu}M$로, 질산염+아질산염의 농도는 $2.03{\sim}15.34{\mu}M$로, 인산염의 농도는 $0.06{\sim}1.82{\mu}M$로, 규산염은 $0.03{\sim}18.3{\mu}M$로 각각 변동하였다. Chl. a농도는 $0.86{\mu}g\;L^{-1}{\sim}37.70{\mu}g\;L^{-1}$로 관찰되었으며, 각 수심별 Chl. a농도의 연평균은 표층에서 $10.35{\pm}8.54{\mu}g\;L^{-1}$로 가장 높았고, 수심증가와 더불어 감소하였다. 박테리아와 종속영양미소편모류는 $0.29{\times}10^6cells\;mL^{-1}{\sim}7.62{\times}10^6cells\;mL^{-1}$$1.00{\times}10cells\;mL^{-1}{\sim}1.26{\times}10^3cells\;mL^{-1}$로 변동하였고, 계절적으로는 하계 박테리아의 생물량이 현저하게 높게 관찰되었을 때 종속영양편모류 또한 높게 나타났다. 결과적으로, 시화호에서 단 주기로 개방되는 배수갑문의 영향으로 경기만 내만일대에 일정의 높은 유 무기물이 공급되면, 이들 탄소원으로 박테리아의 현저한 증식이 하계를 중심으로 일어나며, 이는 미소생물고리로 연결되는 종속영양편모류의 증식에 중요한 역할을 할 것이다.

Keywords

References

  1. Azam F, T Fenchel, JG Field, JS Gray, LA Meyer-Reil and F Thingstad. 1983. The ecological role of water column microbes in the sea. Mar. Ecol. Progr. Ser. 126:97-102.
  2. Baek SH, K You, BS Park and MS Han. 2010. The Seasonal variation of microbial community in the eutriphic brackish water of Lake Shihwa. Korean J. Limnol. 43:55-68.
  3. Bird DF and J Kalff. 1984. Empirical relationships between bacterial abundance and chlorophyll concentration in fresh and marine water. Candian J. Fisher. Aquat. Sci. 41:1015-1023. https://doi.org/10.1139/f84-118
  4. Bird DF and J Kalff. 1986. Bacterial grazing by planktonic algae. Science 231:493-495. https://doi.org/10.1126/science.231.4737.493
  5. Caron DA. 1983. Technique for enumeration of heterotrophic and phototrophic nanoplankton, using epifluorescent microscopy, and comparison with other procedures. Appl. Environ. Microb. 46:491-498.
  6. Cho BC, SC Na and DH Choi. 2000. Active ingestion of fluorescently labeled bacteria by mesopelagic heterotrophic nanoflagellates in the East sea, Korea. Mar. Ecol. Progr. Ser. 206:23-32. https://doi.org/10.3354/meps206023
  7. Choi DH, SW Kang, KD Song, SH Huh and BC Cho. 1997. Distribution and growth of bacteria in the hypertrophic Lake Shiwha. The Sea 2:92-100.
  8. Davis PG, DA Caron, PW Johnson and JMcN Sieburth. 1985. Phototrophic and apochlorotic components of picoplankton and nanoplankton in the North Atlantic: geographic, vertical, seasonal and diel distributions. Mar. Ecol. Progr. Ser. 21:15-26. https://doi.org/10.3354/meps021015
  9. Fenchel T. 1982. Ecology of heterotrophic microflagellates? Quantitative occurrence and importance as bacterial consumers. Mar. Ecol. Progr. Ser. 9:35-42. https://doi.org/10.3354/meps009035
  10. Fenchel T and PR Jonsson. 1988. The functional biology of Strombidium sulcatum, a marine oligotrich ciliate (Ciliophora, Oligotrichina). Mar. Ecol. Progr. Ser. 48:1-15. https://doi.org/10.3354/meps048001
  11. Fukami K, A Watanabe, S Fujita, K Yamaoka and T Nishijima. 1999. Predation on naked protozoan microzooplankton by fish larvae. Mar. Ecol. Progr. Ser. 185:285-291. https://doi.org/10.3354/meps185285
  12. Jardillier L, M Basset, I Domaizon, A Belan, C Amblard, M Richardot and D Debroas. 2004. Bottom-up and top-down control of bacterial community composition in the euphotic zone of a reservoir. Aquat. Microb. Ecol. 35:259-273. https://doi.org/10.3354/ame035259
  13. Jeffrey SW and GF Humphrey. 1975. New spectrophotometric equations for determining chlorophylls a, b, $c_1$, $c_2$ in higher plants, algae and natural phytoplankton. Biochem. Physiologie der Pflanzen 167:191-194. https://doi.org/10.1016/S0015-3796(17)30778-3
  14. Kamphake L, S Hannah and J Cohen. 1967. Automated analysis for nitrate by hydrazine reduction. Water Res. 1:205-216. https://doi.org/10.1016/0043-1354(67)90011-5
  15. Kim CS, HS Lim, JA Kim and SJ Kim. 2009. Residual flow and its implication on macro-tidal flats in Kyunggi Bay Estuary of Korea. J. Coast. Res. SI 56:976-980.
  16. Kim YO, EJ Yang, JH Kang, KS Shin, M Chang and CS Myung. 2007. Effects of an artificial breakwater on the distributions of planktonic microbial communities. Ocean Sci. J. 42:9-17. https://doi.org/10.1007/BF03020906
  17. Kormas K, Ar K Kapiris, M Thessalou-Legaki and A Nicolaidou.1998. Quantitative relationships between phytoplankton, bacter and protists in an Aegean semi-enclosed embayment (Maliakos Gulf, Greece). Aquat. Microb. Ecol. 15:255-264. https://doi.org/10.3354/ame015255
  18. Lee CW, I Kudo, M Yanada and Y Maita. 2001. Bacterial abundance and production and heterotrophic nanoflagellate abundance in subarctic coastal waters (Western North Pacific Ocean). Aquat. Microb. Ecol. 23:263-271. https://doi.org/10.3354/ame023263
  19. Lee WJ, KS Shin and JD Lee. 2007. Studies on marine heterotrophic protists in Masan Bay, Korea. Ocean Polar Res. 29:401-410. https://doi.org/10.4217/OPR.2007.29.4.401
  20. Lee WS and MS Han. 2004. Community structure of plankton in eutrophic water systems with different residence time. Korean J. Limnol. 37:263-271.
  21. Mostajir B, JR Dolan and F Rassoulzadegan. 1995. Seasonl variations of pico-and nano-detrial particles (DAPI yellow particles, DYP) in the Ligurian Sea (NW Mediterranean). Aquat. Microb. Ecol. 9:267-277. https://doi.org/10.3354/ame009267
  22. Naganuma T and S Miura. 1997. Abundance, production and viability of bacterioplankton in the Seto lsland Sea, Japan. J. Oceanogr. 53:435-442.
  23. Park JS and BC Cho. 2002. Active heterotrophic nanoflagellates in the hypoxic water-column of the eutrophic Masan Bay, Korea. Mar. Ecol. Progr. Ser. 230:35-45. https://doi.org/10.3354/meps230035
  24. Poter KG and YS Feig. 1980. The use of DAPI for identifying and counting aquatic microflora. Limnol. Oceanogr. 25:943-948. https://doi.org/10.4319/lo.1980.25.5.0943
  25. Sherr BF and EB Sherr. 1988. Role of microbes in pelagic food webs: a revised concept. Limnol. Oceanogr. 33:1225-1227. https://doi.org/10.4319/lo.1988.33.5.1225
  26. Simon M, BC Cho and F Azam. 1992. Significance of bacterial biomass in lakes and the ocean: comparison to phytoplankton biomass and biogeochemical implications. Mar. Ecol. Prog. Ser. 86:103-110. https://doi.org/10.3354/meps086103
  27. Son JY, SJ Hwang and DS Kong. 2006. Temporal and spatial distribution of biomass and cell size of bacteria and protozoa in Lake Paldang and Kyungan Stream. Korea J. Limnol. 39:379-389.
  28. Weisse T. 1991. The annual cycle of heterotrophic freshwater nanoflagellates: role of bottom-up versus top-down control. J. Plankton Res. 13:167-185. https://doi.org/10.1093/plankt/13.1.167
  29. Yang EJ, JK Choi and JH Hyun. 2003. The study on the seasonal variation of microbial community in Kyeonggi Bay, Korea: I. bacteria and heterotrophic nanoflagellates. The Sea 8:44-57.