Korean Journal of Ecology and Environment (생태와환경)

The Korean Society of Limnology (한국수생태학회)
권호 표지

Characteristics of DOC Release from Sediment in Eutrophic Lake

부영양호 퇴적층으로부터 용존유기물의 용출특성

  • Park, Je-Chul (Dept. of Environmental Engineering, Kumoh National Institute of Technology)
  • 박제철 (금오공과대학교 토목환경공학부)
  • Published : 2003.09.30
Download PDF
⟨ Previous Next ⟩

Abstract

This study was conducted to estimate the internal dissolved organic carbon (DOC) loading from sediment in eutrophic shallow Lake Kasumigaura. Contents of water and organic carbon were about 80% and 6.3% with depth in the sediment, respectively. The highest DOC concentration in porewater (104 mg C/l) was observed in September suggesting that the porewater could play an important role as an internal loading of DOC. Results of DOC release experiments showed that the labile-DOC (L-DOC) release was not detected in the oxic condition, while refractory-DOC(R-DOC) release was detected. The L-DOC and R-DOC release rates in the anoxic codition ranged from 14.5${\sim}$ 48.6, 14.4 ${\sim}$27.3 mgC $m^{-2}$ $d^{-2}$, respectively. The current study showed that L-DOC released in the oxic condition was rapidly utilized by aerobic bacteria, in contrast, L-DOC and R-DOC released in anoxic codition were slowly utilized by anaerobic bacteria. These results suggested that L-DOC and R-DOC were closely related to sediment release and most of the R-DOC released could be an important source of DOC in eutrophic lakes during summer. Therefore, R-DOC pool should be added as one of the important energy source for microbial-based aquatic food webs in eutrophic lakes.

수심이 얕고 부영양 호소인 L. Kasumigaura를 대상으로 퇴적층으로부터 유기물 용출특성을 조사하였다. 퇴적물의 함수율은 약 80%이상을 차지하고 있었으며 공극수의 DOC농도는 표층에서 높고 깊어질수록 감소하는 경향을 나타냈다. 특히 조사기간중 공극수의 DOC농도(104mg C/l)가 크게 증가하여 공극수로부터 수체로 용출 가능성이 높을 것으로 추정되었다. DOC 용출실험결과, 호기조건에서는 Labile-DOC (L-DOC)용출이 거의 관측되지 않았고 Refractory-DOC (R-DOC)만 관측되었으며, 혐기조건에서는 L-DOC와 R-DOC 모두 용출되는 것으로 나타났다. 이러한 결과는 퇴적층의 상부수층에 DO가 충분히 유지되면 L-DOC는 용출되어도 호기성 bacteria에 의해 쉽게 분해되기 매문에 R-DOC만 용출되는 것으로 조사되었으며, 혐기조건하에서는 혐기성 bacteria의 유기물 분해능력의 감소로 L-DOC와 R-DOC모두 용출되는 것으로 나타났다. 결과적으로 내부생성기원의 유기물중 퇴적층으로부터 R-DOC 용출은 수체의 유기물 농도를 증가시키는 주요 원인으로 나타났으며, 수중 유기물의 대부분을 차지하고 있는 R-DOC는 유기물순환에 중요한 역할을 담당하고 있다는 사실이 확인되었다.

Keywords

References

  1. 김범철, 최광순, 김철구, 이유희, 김동섭, 박제철. 1998. 소양호의 DOC와 POC의 분포. 한국육수학회지 31: 17-24.
  2. 박제철. 1998. 용존유기물의 내부생성 메커니즘에 관한 실험적 연구. I. 동물플랑크톤의 영향. 한국육수학회지 31:129-135.
  3. 한국건설기술연구원. 1995. 고도정수처리시스템개발.
  4. 建􃁤􃁿關􂝮􃶀􂱼建􃁤局, 1995. 􄋗ヶ􄈯 􃤻と􃧣􃓊の共􃱏を求めて. 􃆧􃧨􃞧開􂱭公􂚁.
  5. 􂯡􃰏􃼣, 1996. 􄋗ヶ􄈯における􃛱􃱏􃟡機􂮸の擧􂝫と􂾪􃁹機構に關する􃓐究. 􂝮京􃆧􂽫􂚺􄋚 􂯝􂻓􄋚􃞶􂣻􂭎. 58pp.
  6. Baines, S.B. and M.L. Pace. 1991. The production ofdissolved organic matter by phytoplankton and its importantto bacteria: patterns across marine and freshwatersystem. Limnol. Oceanogr. 36: 1078-1090.
  7. Chrost, R.H. and M.A. Faust. 1983. Organic carbon releaseby phytoplankton: its composition and utilization bybacterioplankton. J. Plankton Res. 5: 477-493.
  8. DeMontigny, C. and Y.T. Prairie. 1993. The relative impor-tance of biological and chemical processes in the releaseof phosphorus from a highly organic sediment. Hydrobiologia253: 141-150.
  9. Fukushima, T., J.C. Park, A. Imai and K. Matsushige.1996. Dissolved organic carbon in a eutrophic lake;Dynamics, biodegrability and origin. Aquat. Sci. 58:139-157.
  10. Goma, R.H., M. Aizaki, T. Fukushima and A. Otsuki. 1996.Significance of zooplankton grazing activity as a sourceof dissolve organic nitrogen, urea and dissolved freeamino acids in a eutrophic shallow lake: experimentsusing outdoor continuous flow pond systems. Jpn. J.Limnol. 57: 1-13.
  11. Hama, T. and N. Handa. 1987. Pattern of organic matterproduction by natural phytoplankton population in aeutrophic lake. 2. Extracellular products. Arch. Hydrobiol.109: 227-243.
  12. Jensen, L.M., O.N.G. Jorgensen and M. Sondergaard.1985. Specific activity. Significance in estimating releaserates of extracellular dissolved organic carbon(EOC) by algae. Verh. Internat. Verein. Limnol. 22:2893-2897.
  13. Lampert, W. 1978. Release of dissolved organic carbon bygrazing zooplankton. Limnol. Oceanogr. 23: 831-834.
  14. Ogura, N. 1972. Rate and extent of decomposition of dissolvedorganic matter in surface seawater. Mar. Biol.13: 89-93.
  15. Olsen, S. 1958. Phosphate adsorption and isotopic exchange in lake muds. Experiment with P32; Preliminaryreport. Verh. Internat. Verein. Limnol. 13: 915-922.
  16. Orem, W.H., P.G. Hatcher, E.C. Spiker, N.M. Szeverenyiand G.E. Maciel. 1986. Dissolved organic matter inanoxic porewaters from Mangrove Lake, Bermuda.Geochim. Acta 50: 609-618.
  17. Park, J.C., M. Aizaki, T. Fukushima and A. Otsuki. 1997.Production of labile and refractory dissolved organiccarbon by zooplankton excretion: An experimentalstudy using large outdoor continuous flow-throughpond. Canad. J. Fish. Aquat. Sci. 54: 434-443.
  18. Pomeroy, L.R., E.E. Smith and C.M. Grant. 1965. Theexchange of phosphate between estuarine water andsediments. Limnol. Oceanogr. 10: 167-172.
  19. Servais, P., G. Billen and M.C. Hascoet. 1987. Determinationof the biodegradable fraction of dissolved organicmatter in waters. Water Res. 21: 445-450.
  20. Thurman, E.M. 1985. Organic geochemistry of naturalwater. Kluwer Academic Publishers, Dordrecht, Netherlands,pp. 5-110.
  21. Watanabe, Y. 1984. Transformation and decomposition ofphotosynthetic products of lake phytoplankton. Jpn. J.Limnol. 45: 116-125.
  22. Wetzel, R.G. 2000. Limnology. Saunders Coll. Publ. Philadelphia,pp. 731-783.