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Analysis of the Benthic Nutrient Fluxes from Sediments in Agricultural Reservoirs used as Fishing Spots

낚시터로 활용중인 농업용 저수지의 퇴적물 내 영양염류 용출 분석

  • 주진철 (한밭대학교 건설환경공학과) ;
  • 최선화 (한국농어촌공사연구원) ;
  • 허남주 (한국농어촌공사연구원) ;
  • 유자함 (한밭대학교 건설환경공학과) ;
  • 전준영 (한밭대학교 건설환경공학과) ;
  • 허준욱 (생물모니터링센터)
  • Received : 2017.11.13
  • Accepted : 2017.11.23
  • Published : 2017.11.30

Abstract

For two agricultural reservoirs that are rented for fishing spots, benthic nutrient fluxes experiment were performed two times with two sediments from fishing-effective zone and one sediment from fishing-ineffective zone using laboratory core incubation in oxic and anoxic conditions. During benthic nutrient fluxes experiment, the changes in DO, EC, pH, and ORP in the supernatant were not significantly different between fishing-effective zone and fishing-ineffective zone, and were similar to the sediment-hypolimnetic diffused boundary layer in agricultural reservoir. Except for $NO_3{^-}-N$, more benthic nutrient fluxes of $NH_4{^+}-N$, T-P, and $PO{_4}^{3-}-P$ from sediment to hypolimnetic was measured in anoxic than in oxic conditions (p<0.05). As the DO concentration in hypolimnetic decreases, the microorganism-mediated ammonification is promoted, the nitrification is suppressed, and finally the $NH_4{^+}-N$ diffuses out from sediment to hypolimnetic. Also, the diffusion of T-P and $PO{_4}^{3-}-P$ from sediments to hypolimnetic is accelerated through the dissociation of the phosphorus bound to both organic matters and metal hydroxides. The difference in the benthic nutrient diffusive fluxes between fishing-effective zone and fishing-ineffective zone was not statistically significant (p>0.05). Therefore, it was found that fishing activities did not increase the benthic nutrient diffusive fluxes to a statistically significant level. Due to the short fishing activities of 10 years and the rate-limited diffusion of the laboratory core incubation, the contribution of fishing activities on sediment pollution is estimated to be low. No significant correlation was found between the total amount of nutrients in sediment and the benthic nutrient diffusive fluxes in both aerobic and anaerobic conditions. Therefore, nutrients input from various nonpoint sources of watersheds are considered to be a more dominant factor rather than fishing activities in water quality deterioration, and both aeration and water circulation in hypolimnetic were required to suppress the anoxic environment in agricultural reservoirs.

낚시터로 장기 임대중인 농업용 저수지 2곳을 대상으로 낚시터 영향권(effective zone) 2지점의 퇴적물과 비영향권(ineffective zone) 1지점의 퇴적물을 호기(oxic)와 무산소(anoxic) 조건을 조성한 실험실 코어배양법(laboratory core incubation)을 이용해 영양염류 용출시험을 2회씩 실시하였다. 용출 실험동안 상등수 내 DO, EC, pH, ORP의 변화는 낚시터 영향구간과 비영향 구간 사이에 유의할만한 차이는 관측되지 않았으며(p>0.05), 농업용 저수지의 퇴적물-심층수 확산경계면과 유사한 환경으로 조성되었다. 질산성 질소($NO_3{^-}-N$)를 제외하고 암모니아성 질소($NH_4{^+}-N$), 총인(T-P), 인산염 인($PO{_4}^{3-}-P$)이 호기 보다는 무산조 조건에서 통계학적으로 유의한 수준(p<0.05)으로 퇴적물에서 상등수로 더 많은 용출량이 측정되었다. 이는 상등수 내 DO 농도 감소에 따라 미생물 매개의 암모늄화가 촉진되고 질산화 작용이 억제되어 암모니아성 질소가 퇴적물에서 상등수로 확산 용출되고, 퇴적물 표층의 산화층이 환원되어 유기물에 결합된 인과 금속 산화물과 결합된 인의 해리 등을 통해 인산염인이 퇴적물에서 상등수로 확산용출이 가속화되었기 때문이다. 낚시터 영향권과 비영향권 사이 영양염류 용출량(benthic nutrient diffusive flux)값의 차이는 통계학적으로 유의하지 않았다(p>0.05). 따라서 농업용 저수지 내 낚시활동이 퇴적물의 영양염류 용출량을 통계학적으로 유의한 수준으로 증대시키지 않는 것으로 조사되었다. 이러한 결과는 농업용 저수지 설립년도 대비 10여년의 단기간 낚시활동으로 인해 퇴적물 오염 기여도가 비교적 낮고, 코어배양법의 속도제한된 확산(rate-limited diffusion)으로 발생한 것으로 판단된다. 호기와 무산소 조건 모두에서 퇴적물 내 영양염류 총량과 영양염류 용출량 사이에 유의적 상관관계가 도출되지 않았다. 따라서 농업용 저수지 수질오염의 가속화가 낚시활동으로 인한 직접적 원인보다는 유역에서 유입되는 다양한 비점오염원 내 영양염류가 주요 요인으로 판단되며, 영양염류의 용출을 저감하기 위해 포기 및 물순환 등을 통해 심층수의 빈산소화를 억제할 필요가 있다.

Keywords

References

  1. Kim, J. S., Lee, J. Y., Lee, J. B., Song, C. M. and Park, J. S., "Evaluation of Agricultural Water Supply Potential in Agricultural Reservoirs," J. Korean Soc. Agric. Eng., 58(2), 65-71(2016). https://doi.org/10.5389/KSAE.2016.58.2.065
  2. Lee, K. S., Yoon, K. S., Kim, H. J. and Kim, H. I., "A program of Water Quality Management for Agricultural Reservoirs by Trophic State," Korean J. Environ. Agric. 22(2), 166-171(2003). https://doi.org/10.5338/KJEA.2003.22.2.166
  3. Kim, H. S. and Hwang, S. J., "Sesaonal Variation of Water Quality in a Shallow Eutrophic Reservoir," Korean J. Limnol. 37(2), 180-192(2004).
  4. Ham, J. H., Yoon, C. G., Son, Y. K. and Kim, J. S, "Evaluation of Water Quality Properties in Agricultural Reservoirs using Multivariate Analysis," Korean Soc. Water Qual., 33(1), 39-47(2011).
  5. Choi, S. H., Kim, H. D. and Kim D. H., "The Evaluation of Water Quality Characteristic Using a Multivariate Statistical Analysis in the Artificial Lake," Korean Nat. Committee on Irrig. and Drainage, 21(2), (2014).
  6. http://www.mafra.go.kr/
  7. Song, M. Y., Cho, E. H. and Im, D. H., "Current Status & Policy Issues on Agricultural Water Quality Management in Gyeonggi Province," Gyeonggi Res. Inst(2012).
  8. Ministry of Oceans and Fisheries, "Analytical study of environmental hazards such as fishing weights and baits,"(2006).
  9. Rural Reserach Institute, "Studies on water pollution and the management of water quality of the agricultural reservoirs with the purpose of multiple utilization (II),"(2006).
  10. Rural Research Institute, "The Study on Convergence Technologies Development and Application for Agricultural Water Treatment (II)," (2015).
  11. Ki, B., Lim, B., Na, E. H. and Choi, J. H., "A study on the nutrient release characteristics from sediments in the Asan reservoir," J. Korean Soc. Environ. Eng., 32(1), 1169-1176(2010).
  12. Lee, Y. S. and Shin, S. H, "Effective Reservoir Management Methods using Nutrients Leaching Characteristic Analysis: Case Study of the Hongdong Reservoir," The J. Eng. Geol., 23(2) 95-104(2013).
  13. Kim, K. H., Kim, S. H., Jin, D. R., Huh, I. A. and Hyun, J. H., "A Study on the Measurement Method for Benthic Nutrient Flux in Freshwater Sediment," J. Korean Soc. Environ. Eng., 39(5), 288-302(2017). https://doi.org/10.4491/KSEE.2017.39.5.288
  14. Oh, H. S., Huh, I. A. and Chi, J. H., "Laboratory Study of Phosphorus Fractionation in the Sediments of Yeongsan River," J. Korea Soc. Environ. Eng., 39(9), 519-526(2017). https://doi.org/10.4491/KSEE.2017.39.9.519
  15. Hammond, D. E., Cummins, K. M., McManus, J., Berelson, W. M., Smith, G. and Spagnoli, F., "Methods for measuring benthic nutrient flux on the California Margin: comparing shipboard core incubation to in situ lander results," Limnol. and Oceanogr.: Methods, 2, 146-159(2004). https://doi.org/10.4319/lom.2004.2.146
  16. Belley, R, Snelgrove, P. V. R., Archambault, P. and Jupitor, S. K., "Environmental drivers of benthic flux variation and ecosystem functioning in Salish sea and northeast Pacific sediments," PLos ONE, 11(3), (2016).
  17. Burger, D. F., Hamilton, D. P., Pilditch, C. A. and Gibbs, M. M., "Benthic nutrient fluxes in a eutrophic, polymictic lake," Hydrobiol., 584, 13-25(2007). https://doi.org/10.1007/s10750-007-0582-0
  18. Cowan, J. L., Pennock, J. R. and Boynoton, W. R., "Seasonal and interannual patterns of sediment-water nutrient and oxygen flux in Mobile Bay, Alabama (USA): Regulating factors and ecological significance," Mar. Ecol. Prog. Series, 141, 229-245(1996). https://doi.org/10.3354/meps141229
  19. Kozerski, H. P., and Kleeberg, A., "The sediments and benthic pelagic exchange in the shallow lake Muggelsee (Berlin, Germany)," Internat. Rev. Hydro., 83(1), 77-112(1998). https://doi.org/10.1002/iroh.19980830109
  20. Jensen, H. S. and Andersen, F., "Importance of temperature, nitrate and pH for phosphate release from aerobic sediments of four shallow," Limnol. and Oceanogr., 37, 577-589(1992). https://doi.org/10.4319/lo.1992.37.3.0577
  21. Glud, R. N., Forster, S. and Huettel, M., "Influence of radial pressure gradients on solute exchange in stirred benthic chambers," Mar. Ecol. Prog. Series, 141, 303-311(1996). https://doi.org/10.3354/meps141303
  22. Yoon, I. G., Kim, Y. J., Kim, S. H., Kim, J. H. and Kwon, O. S., "Inorganic Nutrient Fluxes from Sediment of west Nakdong river," Korea J. Limnol., 32, 1-7(1999).
  23. Jeong, H. Y. and Cho, K. J., "SOD and Inorganic Nutrient Fluxes from Sediment in the Downstream of the Nagdong River," Korea J. Limnol., 36(3), 322-335(2003).
  24. Kang, P. G., Lee, S. W., Park, H. K., Kwon, O. Y., Kim, Y. J., Byeon, M. S., Kong, D. S., "Study on the release of Phosphorus and Nitrogen from sediment in Lake Chungju," Korean Soc. Water Qual., 1231-1241(2006).
  25. Kang, P. G., Lee, S. W., Park, H. K., Kwon, O. Y., Kim, Y. J., Byeon, M. S. and Kong, D. S., "Study on the Release of Phosphorus and Nitrogen from Sediment in Lake Soyang," Korean Soc. Water Qual., 957-966(2007).
  26. US EPA, Water quality standards regulations and federally promulgated standards, https://www.epa.gov/standards-water-body-health.

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