연속배양방식으로 서낙동강 저서층의 영양염 용출 및 이에 미치는 환경요인의 영향을 분석하였다. 희석율 감소는 배양기 수층의 영양염 농축을 초래하여 저서층에서 용출되는 N과 P의 용출율을 저하시켰으며, NH4 +와 PO4 3-의 용출은 저산소 조건에서 촉진되었다. 미생물의 활성을 저해하는 저온과 중금속은 NH4 +와 PO4 3-의 용출에는 큰 영향을 미치지 않았지만 NO3 -의 농도에 많은 영향을 미쳐 NH4 +와 PO4 3-의 용출은 무생물학적 요인에 의해서도 많은 영향을 받지만 NO3 -는 질화세균에 의한 용출 NH4 +의 산화로 대부분 생성됨을 알 수 있었다. 낮은 희석율과 용존산소 조건에서 측정한 서낙동강 저서층의 NH4 +와 PO4 3-의 용출율은 각각 평균 20.4 mg-N m-2 day-1, 8.1 mg-P m-2 day-1로, 서낙동강의 평균 수면적과 저수량 및 체류시간을 고려하면 저서층의 영양염 용출이 서낙동강 수층의 NH4 +와 PO4 3- 농도의 6.6~39.8, 63.0~100%에 해당하여 서낙동강의 부영양 화에 상당한 영향을 미치는 것으로 추정된다.

부레옥잠을 이용한 수처리 시설의 설계에 활용될 수 있는 기초자료를 얻고자 인공배지를 이용하여 인, 질소농도와 부레옥잠의 현존량에 따른 인, 질소의 제거량을 예측하였다. 또한 돈사폐수에도 적용하여 인, 질소의 제거율을 검토하였다. 부레옥잠 조직내의 인, 질소함량은 배양수의 인, 질소농도에 따라 각각 0.22~1.02%, 1.4~4.1%의 범위를 보였으나, 배양수의 인, 질소농도가 각각 1.0 mgP/l 이상, 3.0 mgN/1 이상에서는 각각 0.8%,

동해 연안에 위치한 대진, 갈남, 포항, 울산 등 4개 지역의 연안역을 대상으로 1994년 7월부터 1995년 4월까지 계절별로 4회에 걸쳐서 영양염과 유기물질의 분포에 관련된 환경요인, 영양염류, 부유성 유기물질 및 엽록소 함량 등을 조사하였다. BOD는 울산 처용암이 모든 정점 중에서 가장 높게 나타났으며, 영양염류의 농도는 근처에 오염원이 많은 포항과 울산의 처용암에서 전 조사기간 동안에 걸쳐 전반적으로 높았다. 특히, 처용암은 조사된 모든 영양염

이온교환법 또는 흡착법은 기존의 생물학적 처리공정과 연계한 고도처리시스템을 구축하는데 있어 가장 단순하고 안정적인 단위공정의 하나가 되고 있다. 이에 따라 다기능성, 고효율성, 이온 선택성 및 경제성을 갖춘 흡착소재를 개발하기 위해 많은 노력이 이루어지고 있다. 리그노셀룰로오스계 천연 고분자 물질은 자연에 풍부하면서도 저가라는 점에서 다양한 기능성의 흡착소재로 활용되고 있다. 이 중 정미산업의 주요 부산물인 왕겨는 기계적 강도가 높고 일정한 형상과 넓은 비표면적을 가지고 있다는 장점이 있어 생체흡착제 제조 원료로 적합한 특성을 가지고 있다. 우리나라에서는 매년 60만톤 이상의 왕겨가 발생하고 있으며, 이들의 95% 이상이 축산분뇨와 혼합하여 퇴비로 사용되고 있는 실정이다. 본 연구에서는 왕겨의 새로운 재활용 방안으로 생체흡착제 제조를 위한 기질물질로 왕겨의 활용 가능성과 효율성을 검토하기 위해 potassium peroxydisulphate(K2S2O8)를 산화-환원 개시제로 하는 그라프트 중합반응을 통해 왕겨표면에 glycidyl methacrylate(GMA)를 화학적으로 결합시켜 에폭시기(-COC-)를 도입하고, Diethylenetriamine(DETA)과 반응을 통해 에폭시기에 아민기(-NH)를 도입하는 방법으로 음이온 흡착기능성 왕겨흡착제(RH-g-GMA-DETA)를 제조한 다음, 회분식 흡착실험을 통해 아민형 왕겨흡착제의 NO3-N와 PO4-P에 대한 흡착효율 및 흡착특성을 평가하였다. 아민형 왕겨흡착제 RH-g-GMA-DETA의 NO3-N와 PO4-P에 대한 흡착은 Fruendlich 흡착등온식보다는 Langmuir 흡착등온식과 잘 일치하였으며, Langmuir흡착등온식으로부터 구한 최대 단일층 흡착량은 NO3- 68.5 mg/g, PO43- 129.8 mg/g이었다. 흡착은 NO3- 와 PO43- 모두 20분 이내에 평형에 도달할 정도로 빠르게 진행되었으며, 2차 흡착속도식과 잘 부합하는 특성을 보여 chemisorption이 속도결정단계에서 중요한 역할을 함을 알 수 있었다. D-R모델로부터 추산한 흡착에너지는 NO3- 가 9.3 kJ/mol, PO43- 가 140 kJ/mol로 각각 이온교환과 화학적 흡착이 주된 흡착메카니즘으로 작용하였음을 나타내었다. 공존 음이온간 흡착선택성과 흡착에 미치는 pH 영향을 동시에 살펴 본 결과 RH-g-GMA-DETA의 흡착선택성은 SO4>PO4>NO3≥NO2>F의 순이었으며, SO4는 pH의 영향을 거의 받는 흡착특성을 보이는 반면, PO4는 pH가 증가할수록 흡착량이 증가하는 특성을, NO3, NO2 및 F는 pH 5 이상에서는 흡착량이 급격히 감소하는 특성을 보였다.

This paper focuses on the impacts of waste dumping on inorganic nutrients in the dumping area of the Yellow Sea, and the effect of an governmental regulation of pollution in dumping areas. The environmental variables and parameters of the dumping and reference areas in the Yellow Sea were measured during July 2009 and analyzed. In addition, the analyzed data for inorganic nutrients over the last 10 years were obtained from the Korea Coast Guard (KCG) and the National Fisheries Research and Development Institute (NFRDI). The chemical environment of the study area revealed increases in concentrations of inorganic nutrients, Chemical Oxygen Demand (COD), and Volatile Suspended Solids (VSS) in the bottom layer. On the contrary, the pH level was decreased. Most notably, the time series data of inorganic nutrients showed gradual increase over time in the dumping area, and thus, the oligotrophic waters trend toward eutrophic waters. The increases appears to be due to the disposal of large amounts of organic waste . In recent times, the wastes disposed at the area were largely comprised of livestock wastewater, and food processing waste water. The liquefied waste, which contains an abundance of nutrients, causes a sharp increase in concentrations of inorganic nitrogen in the dumping area. On the one hand, the dumping sites have been deteriorated to such an extent that pollution has become a social problem. Consequentially, the government had a regulatory policy for improvement of marine environmental since 2007 in the dumping area. Hence, the quality of marine water in the dumping site has improved.

An algal assay procedure using an indigenous phytoplankton assemblage was tested to estimate the propagation of red tide phytoplankton species and determine the optimal time interval at which to measure growth yield in eutrophic marine waters where red tides frequently occur. Various red tide phytoplankton species were propagated on a large scale by adding nitrogen or phosphorous. This procedure was useful for estimating the limiting nutrient, elucidating the mechanisms underlying red tides, and determining the levels of increases in organic matter in eutrophic coastal waters. The algal assay using indigenous C. polykrikoides showed that this species did not always propagate, apparently because of very low concentrations of trigger elements that are necessary for its growth, rather than as a result of other environmental characteristics, e.g., water temperature or stress from sampling. In the winter, when water temperatures are lower than in spring, summer, or autumn, maximum propagation and the limiting nutrient could be estimated by measuring phytoplankton biomass at 2–3-day intervals. However, in the other seasons, when water temperatures are higher, phytoplankton biomass should be measured at 2-day intervals. In particular, daily monitoring will be required to determine precise growth yields in warm seasons.

In order to study the temporal variations of nutrients and chlorophyll-a in the Bottol Bada, three field observations were carried out on 20, 23 and 26 July, 2004. The low N:P values exhibit nitrogen deficiency during the periods of observation. This result is not representative of typical summer environment in the southern coast of Korea. The possible mechanisms are as follows: 1) The freshwater inflow was not sufficient for the supply of nitrogen because the total precipitation was 11.9 mm in July, 2004. This amount is no more than 5% in normal precipitation in July. 2) There was an inflow of oceanic water under the subsurface into the Bottol Bada. Even though the oceanic water comprises more nutrients, it produces the stratification between the surface and the subsurface water and seems to prevent the supply of nutrinets to the surface layer. 3) The high chlorophyll-a concentration of 1.2 μg/L was shown near the narrow channel between Gae-do and Geumo-do. This seems to be resulted from the inflow of water from Gamak Bay.

The three-dimensional eco-hydrodynamic model was applied to estimate the physical process in terms of nutrients and net uptake(or regeneration) rate of nutrients in Kamak Bay for scenario analysis to find proper management plan. The estimation results of the physical process in terms of nutrients showed that transportation of nutrients is dominant in surface level while accumulation of nutrients is dominant in bottom level. In the case of dissolved inorganic nitrogen, the results showed that the net uptake rate was 0～60 mg/m2/day in surface level(0～3m), and the net regeneration rate was 0.0～10.0 mg/m2/day in middle level(3～6m) and above 10 mg/m2/day in bottom level(6m～below). In the case of dissolved inorganic phosphorus, the net uptake rate was 0.0～3.0 mg/m2/day in surface level, and the net regeneration rate was 0.5～1.5 mg/m2/day in middle level and 1.0～3.0 mg/m2/day in bottom level. These results indicates that net uptake and transport of nutrients are occurred predominantly at the surface level and the net generation and accumulation are dominant at bottom level. Therefore, it is important to consider the re-supplement of nutrients due to regeneration of bottom water.

A significant fraction of nutrients, such as nitrogen and phosphorus released from sediment are utilized by primary production in the shallow water of coast and lake. The purpose of this study is to introduce the mechanism of nutrients release from sediment and to introduce the methods of the measurement of nutrient released from sediment. One approach is to calculate nutrients released from sediment by a concentration gradient between sediment pore waters and overlying water based on the Fick's law. The other approaches of measurement are the undisturbed sediment core experiments and measurement of nutrient released from sediment by the in situ chamber equipment.

This study was to evaluate the impact of river runoff and salt intrusion by tide on nutrient balance of estuary during a complete tidal cycle. 24 hours time series survey was carried out during a spring tide July 2001 on a tidal estuary in the Keum river. Three stations(A,B,C) were set along a transect line of about 10km, which linked the lower part of estuary dyke to the subtidal zone. Surface water was sampled simultaneously at each station every hours for the determination of nutrients. Water temperature, pH and dissolved oxygen were measured in situ. Riverine input of silicate and nitrate during ebb tide significantly increased the concentration of all stations. Conversely, during high tide, nutrient concentration were lowered by the mixing of fresh water with sea water. Ammonium nitrogen concentration were higher at intertidal zone(Stn.B) due to sewage inflow to Kyeongpo stream and ammonium release under anaerobic conditions. Also, these results was discussed as a biological component that influences the processes of nutrient regeneration within the estuary. Best correlations were found at lower part of estuary dyke(Stn.A) for salinity against DIN(Y=0.121 Sal.+4.97, r2=0.956) and silicate(Y=0.040 Sal.+2.62, r2=0.785). But no significant correlation was found between salinity and ammonium. Unbalanced elemental ratio(N/P, Si/N and Si/P) depended significantly on the import of nutrients (silicate & nitrate nitrogen) from river and stream. The effect of the tidal cycle and river runoff is important that in determining the extend of the variations in nutrient concentrations at all station.

The purpose of the present study is to estimate the release of dissolved inorganic nitrogen and phosphorous from sediments of Deukryang Bay. One method used in this study is to calculate nutrients released from a concentration gradient between sediment porewaters and the overlying water based on the Fick`s law, and the other method is to measure nutrients released from the sediment-core experiments. The calculated and measured ammonium released from the sediments were 8.93㎍-atN/㎡·hr and 60.4㎍-atN/㎡·hr, respectively in July. 8.57㎍- atN/㎡·hr and 32.9㎍-atN/㎡·hr, respectively in October. The ammonium was released more highly in July than in October, and the measured ammonium flux was higher than the calculated one. The calculated nitrate plus nitrite released from the sediments were 0.31㎍-atN/㎡·hr in July and 0.84㎍-atN/㎡·hr in October. The measured nitrate plus nitrite released from the sediments was 282㎍-atN/㎡·hr in October. The calcuated was lower than the measured because the content of the nutrients in the sediments was always much more than in the overlying waters, and it has shown a differently seasonal pattern compared to the ammonium flux. The calculated phosphorous released from the sediments were 0.97㎍-atN/㎡·hr and measured negative fluxed -6.50 ㎍-atN/㎡·hr in July, and calculated 0.18 ㎍-atN/㎡·hr and measured 24.6 ㎍-atN/㎡·hr, respectively in October.

To investigate characteristics of biogeochemical environment of the Korea Deep Ocean Study(KODOS) area in the northeast Pacific Ocean, we preferentially measured inorganic nutrients and fluorescent organic matters. Typically, the permanent thermocline was well developed at the depth of 200∼1000m in the study area. Nitrate, phosphate and silicate were low in the surface mixed layer and increased with depth. N/P and N/Si showed 15 and 0.2 respectively in the deeper layer. Two fluorophores, biomacromolecule(protein-like) and geomacromolecule (humic-like), were observed by three dimensional fluorescence excitation/emission spectra matrix. Biomacromolecule(maximum fluorescence at Ex_280nm/Em_330nm) ranged from 41.9 to 147.0 TU with its maximum in the surface mixed layer and minimum in deeper water. This is a same trend that has been reported for DOC in the equatorial Pacific. This suggests that biomacromolecule might be labile and converted to refractory humic substance after bacterial degradation in the deeper layer. On the contrary, geomacromolecule(maximum fluorescence at Ex_330nm/Em_430), ranged from 7.6 to 46.5 QSU, showed minimum in the surface mixed layer(euphotic zone) implying photodegradation and then increased with depth at all stations. In the characteristics of vertical profiles, the relationship between biomacromolecule and geomacromolecule showed negative correlation. Such trend can be attributed to biochemical regeneration or formation of fluorescent materials accompanying oxidation and remineralization of settling organic matter.