낙동강에서 chlorophyll - a 와 BOD 의 상관관계

신성교,박청길,이수웅 ( Sung Kyo Shin,Chung Kil Park,Su Woong Lee ) 한국물환경학회 1996 한국물환경학회지 Vol.12 No.4

The relationships between chlorophyll-a(Chl.a) and BOD were investigated through culture and degradation study of phytoplankton and field samples to determine the autochthonous BOD caused by the phytoplankton production in the eutrophic waters in the Nakdong River. The correlation coefficients between Chl.a and BOD, and Chl.a and COD were found to be 0.732 and 0.666 respectively. From the results of culture and degradation of phytoplankton in laboratory, the correlation coefficients between Chl.a and BOD were 0.876(mean value), and 0.968 respectively. Therefore, it was possible to express as TBOD = α. chl.a + allochthonous BOD, and to determine the contribution of autochthonous BOD to total BOD in the Nakdong River. It was found that the percentages of autochthonous BOD in total BOD were 51.7, 47.9, 65.2, 30.5 and 52.6 % at Mulgum, Namji, Jukpo, Koryong and Waekwan. The converting factor(α) for the calculation of autochthonous BOD was depended upon the biomass of phytoplankton as well as the activity, which was changed in accordance with waters conditions. It was found to be 0.042, 0.036, 0.047, 0.029 and 0.048 at Mulgum, Namji, Jukpo, Koryong and Waekwan.

최소비용 처리방안에 의한 낙동강의 수질관리

신성교(Sung Kyo Shin),박청길(Chung Kil Park),이석모(Suk Mo Lee) 大韓環境工學會 1996 대한환경공학회지 Vol.18 No.11

낙동강 중 , 하류수역에서 클로로필 α 최대농도 출현지역 평가

신성교(Sung Kyo Shin),백경훈(Kyung Hoon Baek),송미경(Mi Koung Song) 한국하천호수학회 2002 생태와 환경 Vol.35 No.1

The frequent occurrence of excessive phytoplankton populations in the downstream Nakdong River has been an important water quality problem in recent years. The limnological survey of the Nakdong River was conducted from January 1997 to December 1999 on once or twice per month. A typical phenomenon of eutrophication appears with the persistent algal bloom due to high nutrients in the mid-lower part of the river. This study showed that the point at which Chl. a concentration reaches maximum was affected by the water temperature and the flow rate. For example, Chl. a concentration reached maximum after around 380, 240 and 120 hours which were estimated from the time of flow at low(≤10℃), mean(10∼20℃) and high(≥20℃) water temperature conditions, respectively. It was estimated that increase coefficients of phytoplankton (Chl. a) on the water temperature are 0.201, 0.254 and 0.289 day^-1, on the contrary, decrease coefficients are -0.012, -0.128 and -0.193 day^-1 in low, mean and high water temperature. therefore, to prevent formation of Chl. a maximum concentration in the specific water resource, it is necessary to increase the discharge of dam as well as to decrease.

낙동강 하구 해역의 자생COD 평가

신성교 ( Sung Kyo Shin ),박청길 ( Chung Kil Park ),송교욱 ( Kyo Ouk Song ) 한국수산학회 1995 한국수산과학회지 Vol.28 No.3

낙동강 하구를 대상해역으로하여 자생COD 농도를 구하기 위해 3가지 방법을 적용하고, 각 방법간의 적용성을 평가한 실험으로부터 다음과 같은 결론을 얻었다. 낙동강 하구 해역의 부영양화도 평가 지수는 5.0~111.0로 부영양화 기준 지수 1을 훨씬 초과하여 과영양단계에 있는 것으로 나타났다. 낙동강 하구 조사해역의 총COD중 자생COD 비는 0.5~44.9%의 범위였으며, 계절별로는 하계에 가장 높은 비율을 보였다. 지점별로는 하계에 정점 6에서 평가방법 평균 43.5%로 가장 높은 비율을 나타내었다. 염분농도를 이용한 평가법은 낙동강 하구에서 하구언의 수문조작에 따른 하천수의 부정기적인 유입으로 인해 자생COD를 평가하기에 부적절한 방법이었다. △COD법과 COD와 Chl.a와의 상관성을 이용해 자생COD 농도를 평가하는 방법은 하계 전조사해역에서 상대오차 20%이내의 값을 보여 낙동강 하구 해역의 자생COD평가를 위한 적절한 방법임을 알 수 있다. To determine the autochthonous COD caused by the production of phytoplankton, three different methods were used simultaneously utilizing several environmental factors and applied to the Nakdong Estuary. From the estimation of the tropic state index, tropic level in the Nakdong Estuary was found to be in excess of eutrophication level at all area studied. The percentage of autochthonous COD in total COD was largest in summer and in station No.6 (43.5%). Using of the relationship between COD and salinity was not appropriate for the evaluation of the autochthonous COD due to discrepancy with other results evaluated. However, the evaluations of autochthonous COD obtained from the △COD and the relationship between COD and chl.a were found to be proper methods, resulting in a relative error less than 20% for all of the area investigated.

한국수산업의 EMERGY 분석

손지호(Ji Ho SOHN),신성교(Sung Kyo SHIN),조은일(Eun Il CHO),이석모(Suk Mo LEE) 한국수산과학회 1996 한국수산과학회지 Vol.29 No.5

Fisheries products have to be produced and maintained by work processes from the environment, sometimes helped by people. In Korean fisheries both environmental production and its economic use are included within the windows of system approach. EMERGY is the sum of all inputs expressed as one form of solar energy required directly and indirectly to make a product. Calculating EMERGY flows into Korean fisheries evaluates the real wealth contributed by environmental production and its economic use. Several indices calculated from EMERGY analysis table and a three-arm diagram give perspective on the type and efficiency of the environmental uses. Net EMERGY yield ratio is a measure of its net contribution to the economy beyond its own operation. For adjacent waters fisheries in Korea, the net contribution to the economy is 11.85 or higher, which is a stimulus to the economy that is able to purchase it. EMERGY investment ratio measures the intensity of the economic development and the loading of the environment. The ratio for Korean fisheries as a whole is 0.50, for the adjacent waters fisheries 0.09 and for the shallow-sea cultures 1.28, which is lower than the same index for the industry of the developed country (7.0). The component of environment drawn into production are large compared to purchased investment in Korean fisheries. Much more EMERGY is contained in fisheries products than in the paid services used to process the products. The EMERGY exchange ratio for Korean fisheries as a whole is 6.98, for the adjacent waters fisheries is 10.69 and for the shallow-sea cultures is 1.25. Using market values to evaluate wealth of environment resources is found to be many times too small. Money is paid only to people for their contribution, and never to the environment for its contribution. Macroeconomic value is the appropriate measure for discussing large-scale considerations of an economy, including environment and human goods & services.

통계분석법을 이용한 낙동강 수질특성 평가

박해식(Hae Sik Park),박청길(Chung Kil Park),송미경(Mi Koung Song),백경훈(Kyung Hoon Baek),신성교(Sung Kyo Shin) 한국물환경학회 2001 한국물환경학회지 Vol.17 No.6

The study was conducted to evaluate water quality utilizing factor analysis in the Nakdong River. The relationships between BOD concentration and flow rate, weighted BOD concentration which it was considered BOD load and flow rate, show that water quality in the lower stream is affected by flow rate, especially, in winter and spring. The three factors derived from the factor analysis explained 75.0% of the variability within the data. Factor I (44.0%) was artificial pollution pattern by domestic sewage and industrial wastewater. Factor II (19.2%) was metabolism pattern. Factor III (11.75%) was hydrological variation pattern. The upper stream was influenced of hydrological factor and the water clarity in the middle stream was related to artificial pollution. The lower stream including Mulgum was strongly affected by the metabolised factor.

동계 낙동강 하류 물금수역에서의 수질악화 원인구명

송미경(Mi Kyung Song),박청길(Chung Kil Park),이석모(Suk Mo Lee),백경훈(Kyung Hoon Baek),신성교(Sung Kyo Shin),송교욱(Kyo Ook Song) 한국물환경학회 2000 한국물환경학회지 Vol.16 No.3

The study was performed to find the cause of high concentration of BOD and algal bloom during winter season at Mulgum in the downstream of Nakdong River since 1995. There was high correlationship between BOD concentration and Chl. a contents which shows that algal bloom makes Autochthonous BOD. The dominant algae during of winter blooming season was Stephanodiscus sp.. This algae maintained the blooming under the condition of low water temperature, long retention time with decrease of flow rate, and abundant nutrient concentration. To reduce the amount of Stephanodiscus sp. biomass, it is important to decrease the loading of TP and TN from the upstream, because of the possible approach to control.

주성분 분석법을 이용한 낙동강 하구 해역의 수질 평가

신성교,박청길,송교욱 한국환경과학회 1998 한국환경과학회지 Vol.7 No.2

This study was conducted to evaluate water quality utilizing principal component analysis in the Nakdong River Estuary. From the results of analysis, water quality in the Nakdong River Estuary could be explained up to 65.3 percentage by three factors which were included in river loading(wastes from the Nakdong River and rainfalls ; 39.1%), sediment resuspension(13.7%) and metabolism(12.5%). In the eastern part of estuary in flowing the Nakdong River, river loading factor score(factor 1)was higher than that in western part. Sediment resuspension factor score(factor 2) was high in shallow water, while metabolism factor score(factor 3) was high in deeper water. For seasonal variations of factors score, factor 1 was highly related to rainfall season.

MBOD 법에 의한 낙동강의 조류증식 제한인자 추정

송교욱,서인숙,신성교,이석모,박청길 한국환경과학회 1995 한국환경과학회지 Vol.4 No.5

The increase of population and industrial activities had brought into eutrophication in the Nakdong river. A remarkable acceleration of eutrophication brought about serious problems for water supply. Therefore, for the purpose of conservation of water quality in the Nakdong river it is necessary to control nutrients. MBOD method was used to evaluate algal growth limiting factor and algal growth potential in the Nakdong river from June to August 1994. The modified biochemical oxygen demand(MBOD) depends on the amount of available inorganic nutrient and organic substrate during 5 day incubation in the dark at 20℃. The MBOD assay depends on inorganic nutrients such as P and N as well as reduced carbon and called the MBOD, the MBOD-P, and the MBOD-N, respectively. The results of bioassay by MBOD(Modified BOD) method showed that the MBOD, MBOD-P and MBOD-N value were found to be in the ranges of 3.8∼96.0 ㎎O_2/ℓ, 5.6∼94.0 ㎎O_2/ℓand 42.0∼220 ㎎O_2/ℓ, respectively. And the the bioassay value was found to be the highest in Koryong area and the lowest in Waekwan area throughout the Nakdong river. The variations of MBOD-P and MBOD-N value showed similar tendencies to the variations of phosphorus and nitrogen value, respectively. By MBOD method, the relationships of MBOD, MBOD-P and MBOD-N value were MBOD ≒ MBOD-P ≪ MBOD-N. The MBOD value was nearly equal to the MBOD-P value, and the MBOD-N value was 3 to 20 times more than the MBOD-P value, approximately. Therefore, in the Nakdong river, phosphorus was the limiting factor for algal growth during summer season. The algal growth potential as the concentration of chlorophyll-a in the summer was maximum 5 times more than standing crop as it.