밀양강 수계 7개 지점에 대하여 1997년 4월부터 12월까지 5회에 걸쳐 채집된 저서성 대형무척추동물의 군집분석 및 저서성 대형무척추동물에 의한 생물학적 수질평가 결과를 요약하면 다음과 같다.
분류군은 총 3문 8강 15목 37과 45속 81종으로서 빈모류 1종, 거머리류 2종, 복족류 6종, 부족류 5종, 갑각류 2종, 곤충류 65종으로 곤충류가 가장 많았다.
전체 지점에 대한 평균 개체수 현존량은 815개체/㎡였다. 이 중 곤충류(약80%)가 가장 많았으며, 다시 곤충류 중에는 하루살이류(약 70%)와 날도래류(약 18%)가 주를 이루었다. 각 지점별 평균개체수 현존량을 보면, 제1지점인 청도천의 경우 262개체/㎡(32.2%)로서 가장 많은 출현율을 보였고, 제7지점인 밀양강 끝지점의 경우 38개체 /㎡(4.7%)로서 가장 출현율이 낮았다.
전체 평균 수준에서의 제1우점종은 Ecdyomurus levis Navas였으며, 우점도지수는 0.3이었다. 각 지점별 우점종을 보면 제1지점부터 제5지점까지는 Ecdyomurus levis Navas이였고, 제6지점과 제7지점은 Hirudinidae sp.1이었다. 그리고, 전체 평균 수준에서의 다양도지수는 2.66이었다. 조사지점별 평균 다양도 지수를 보면 제4지점이 가장 높았으며(H'=3.47), 다음은 제2지점, 1지점, 3지점, 5지점, 6지점, 7지점의 순이었다.
생물학적 지표종을 중심으로한 수질평가에 의하면, 밀양강 전체의 평균은 군오염지수(GPI) 1,49로서 β-mesosaprobic의 II급수로 평가되었다. 각 지점별로는 제3지점의 경우 Oligosaprobic의 I급수로서 가장 양호한 수질이었고, 제1지점과, 제2지점, 제4지점, 제5지점은 β-mesosaprobic의 II급수로, 제6지점은 β-mesosaprobic의 III급수로 평가되었다. 그리고, 제7지점은 α-mesosaprobic의 III급수로서 가장 수질이 불량한 것으로 평가되었다.
This study was carried out to evaluate off-shore water quality and to draw marine pollution map to Southern sea in Korea by bioassay using gametes and early development system of Asterias amurensis. From the bioassay, it was determined that the water qualites of Southern sea maintained the grade Ⅱ, because development of A. amurensis were moderately inhibited. However, Sunchon, Kwangyang, and Jinhae Bay belonged to grade Ⅲ, because development of A. amurensis were strongly inhibited. This could be due to the inflows of several river systems and poor water circulation.
The water quality at Yosu island was the grade I, because A. amurensis were not inhibited in its early development.
The analysis of groundwater quality in Kyungnam Province was conducted using monitoring results obtained during 1994. According to the analysis, most heavy metals and pesticides listed in Korean drinking water standards were not detected in Kyungnam Province groundwater, but arsenic and volatile organics such as TCE and PCE were detected. Four inorganic contaminants were detected and frequency of violating the standards was in order of NO_3-N, F^+, As, NH_3-N. Of organics, TCE and PCE were the only contaminants detected. TCE more frequently violated the standards than PCE. Correlation was investigated among contaminants detected in Kyungnam Province groundwater. The correlation results showed that high correlation existed among dissolved solids, hardness, and SO_4^2-.
In order to manage the water quality from the flowing streams in Cheju Island, the characteristics of water quality was investigated from August, 1996 to May, 1997 and the pollutant loadings for future were estimated from the watershed at each stream.
Comparing the mean concentrations of each water quality with the criterion of water quality in river, it was under I class except for Changgo Stream, for DO, under I class at the whole station for SS and under Ⅱ class for BOD.
As the pollutant loadings at each stream in 2020 is compared with those in 1996, the estimated results are as follows : 1) for BOD, 59% at Donghong Stream, 24% at Yeonoe Stream, 44% at Ohngpo Stream and 57% at Changgo Stream. 2) for T-N, 91% at Donghong Stream, 76% at Yeonoe Stream, 63% at Ohngpo Stream and 89% at Changgo Stream. 3) for T-P, 69% at Donghong Stream, 42% at Yeonoe Stream, 45% at Ohngpo Stream and 73% at Changgo Stream
The point source loadings discharged through combined sewer could be treated at sewage treatment plant. However, the expected slow decreasing rate of BOD, T-N, and T-P loadings is due to the part of untreated nonpoint source loadings. Nonpoint source loading overflow typically occurs when the flow of stormwater combined with sewage exceeds the capacity of the interceptor sewers. Since most of the sewers used in Cheju Island are the combined sewers, the combined overflow sewage is bypassed into the receiving water area after a rainstorm. Therefore, a means to control nonpoint source loadings should be considered for the river and marine water quality management.
It is necessary to quantitatively asses the influence of tidal currents to analysis the coastal current patterns before or after constructing offshore structures like as breakwaters. This assesment can be made through the use of simulation models designed to reproduce the water movements of the area. And it is very important to predict a phenomenon of pollutant dispersion in the area. In this study, in order to predict the changes of sea water quality for the port development plan, Ilgwang harbour, located at the east coast of Pusan, the numerical computations were carried out. The flow patterns were investigated before and after the development of the harbour bay and coastal area connected on it. The computational models are an extension of earlier work on the flow which used the ADI Method (Alternating Direction Implicit Method) in appling to Osaka Bay by KANEKO et al. The transport of pollutant constituents depends upon the currental characteristics of the water-transporting medium. In the currental flow model, water velocities and water levels are computed throughout the regions of it. These value are then used in the mass-balance equation to obtain the pollutant-constituent transport. As a result of this research, the present water quality of Ilgwang harbour and the coastal areas connected on it was proved out some good condition. The changes of sea water quality due to the port development plan of the Ilgwang habour bay and the coastal area were not large compared with the present condition, but it will be likely able to get worse by increasing the semi-enclosed areas in the harbour bay. In order to improve the water quality of the area after development, the method to activate tidal exchange in the area can be needed, as a mitigation technique.
도시하천의 유출 및 수질특성을 홍제천 시험유역에서의 관측자료에 의하여 분석하였다. 시험유역의 수질은 건기시차집 관로에 의한 하수의 차단으로 비교적 양호한 수질을 보이는 반면, 이로 인하여 동기의 약 3-4개월동안에는 건천화의 현상을 보였다. 한편, 우기시에는 합류식 하수계통으로부터의 급격한 비점원 오염부하량의 증대를 보였다. 도시유출 및 수질을 해석하는 모형, SWMM, ILLUDAS, STORM, HEC-1 등을 적용하고 그 결과를 비교분석하였다. 또
지하수질 감시를 위한 관측은 지하수를 사용하는 주변 인구의 보건은 물론이고 궁극적으로는 지하수자원 보전이라는 측면에서 매우 중요하다. 그러나 지하수 수질관측망은 설계부터 운영에 이르기까지 임의적이고, 체계적이기보다는 경험에 의존하거나 과학적이지 못한 방식으로 시행되고 있는 것이 사실이다. 본 연구는 지하수질 관측망의 효율적 배치를 위한 방법론의 현장적용성을 검토하기 위하여 대표적인 설계방법론을 대상으로 비교연구 하였다. 그 결과, 지하수질 관측망의 설계
This study was conducted to evaluate water quality in the Keum River estuary using principal component analysis. The results was summarized as follow;
Water quality in the Keum River estuary could be explained up to 70.40% by three factors which were included in the inffluent loading by the Keum River and Kyungpo cheon(38.99%), seasonal variation and organic matter pollution(19.05%), sediment resuspension and internal metabolism(12.35%).
For spatial variation of factor score, artificial pollutant loading is highest at st.1, below Keum River barrage, and decreases toward the outer sea.
For annual variation of factor score, factor 1 was highly related to artificial pollutant loading, and it was greatly increased in 1994. Also, organic matter pollution, sediment resuspension and internal metabolism were increased to every year.
is necessary to control the nutrient loading by Keum river and Kyongpo cheon for Water quality management of estuary.
To examine water pollution status of agricultural water source of greenhouse area in Gyeongnam, the ground water quality was investigated six times at five areas in Gyeongnam from October in 1995 to March in 1996.
pH of ground water were generally in the range of 5.9∼7.6. But a site in Changnyeong area was out of the range in 6.0∼8.5 which is water quality standard for agriculture. COD of ground water was below 8.0㎎/ℓ which is water quality standard for agriculture in all areas and the average was below 2.8㎎/ℓ.
NH_4^+ -N contents in ground water was very low in all areas and the average of NO_3^- -N contents in Changnyeong and Chinju area was high with 13.2 and 11.5㎎/ℓ, respectively. Hardness, SO_4^2- and EC of ground water in Haman were higher than any other area.
Fe and Mn contents of ground water in Kimhae were higher than any other area with 7.17 and 0. 95㎎/ℓ, respectively. Heavy metals such as Cu, Cd, Pb and Zn of ground water were below water quality standard for agriculture but some sites were over.
Between COD and SS in ground water were not correlated with r=0.328, but between COD and NH_4^+ -N were positively correlated. And EC was positively correlated with Ca^2+, Mg^2+ and SO_4^2-.
Ground water pollution status of agricultural water source of greenhouse area in Gyeongnam was generally high in order of Sacheon < Chinju < Haman < Kimhae < Changnyeong.
One hundred and thirty two ground water samples from the Ulsan area were divided into urban and non-urban groupings and were assessed between 1993 and 1996. The results of statistical analysis were as follows:
There were significant differences between the two groupings in the average value of the following water quality parameters: total hardness, nitrate, pH, iron, ammonia and chloride ion in the order of Z-score.
Because total hardness, nitrate, and pH were also significant in ANOVA test, these three parameters can be regarded as the most sensitive parameters of artificial pollutants. By the comprehensive comparison of Ulsan water quality to that of Kangwon-do, all of the major parameters(pH, KMnO_4 consumption, sulfate, chloride and hardness except nitrate) were confirmed as being significantly increased levels.
This study was carried out to develop the stream water quality model for the intaking station of Kongju waterworks in the Keum River system. The monthly water quality(total nitrogen and total phosphorus) with periodicity and trend were forecasted by multiplicative ARIMA models and then the applicability of the models was tested based on 7 years of the historical monthly water quality data at Kongju intaking site. The parameter estimation was made with the monthly observed data. The last one year data was used to compare the forecasted water quality by ARIMA model with the observed one. The models are ARIMA(2,0,0)×(0,1,1)_12 for total nitrogen, ARIMA(0,1,1)×(0,1,1)_12 for total phosphorus. The forecasting results showed a good agreement with the observed data. It is implying the applicability of multiplicative ARIMA model for forecasting monthly water quality at the Kongju site.
The water quality and phytoplankton communities of the coastal waters of Inchon were investigated 4 times from May, 1995 to January, 1996. The characteristic of the study was shallow muddy bottom environment with high SS concentration. The water qualities were belong to the category of I-grade in DO, Ⅱ to Ⅲ grade in COD and Ⅲ-grade in inorganic nutrients such as T-N and T-P. Total 136 species of phytoplankton were observed in this study and species richness was on the decrease compared with the results of previous studies. The mean of phytoplankton species diversities was 1.93, decreased in recent years and the value in autumn was slightly higher than that in other seasons.
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.
The purpose of this study was to investigate the pollutions of water qualities in 30 water samples from Nakdong River, Western Nakdong River, and Suyoung Stream. COD, BOD, T-N and negative ions(F-, Cl- NO3-, SO42-) of water samples were analyzed and the correlationships between water qualities were examined.
The mean concentrations of COD(20.26ppm), BOD(25.36ppm), and T-N(18.05ppm) were the highest in the water sample of Suyoung Stream among the three streams and those of F-(0.25ppm), Cl-(27.70ppm), and SO2-(37.66ppm) in Western Nakdong River, that of NO_3,(10.81ppm) in Nakdong River. The water quality of Suyoung Stream was the worst among the three streams in Pusan area. The correlationships between water qualities were as follows ; BOD and COD showed very high correlationship(correlation coefficient, r=0.97), SO42- and NO3- did high one(0.75), and NO3- and COD, BOD did relatively high ones(0.56 and 0.48, respectively).
Environmental problems caused by certain geologic conditions include pollution of soil by heavy metal, acidization of soils, acid mine drainage, ground-water pollution, and natural radioactivity, as well as geological hazards such as landslide and subsidence. The acid mine drainage contains large amount of heavy metals and, therefore, cause serious pollution onto the nearby drainage systems and soils. In spite of this prospective environmental danger, few studies have been done on the acid mine drainage derived from non-metallic ore deposits such as pyrophyllite(Napseok) deposits. The sulfide-bearing pyrophyllite ores, alteration zones, and mine tailings of pyrophyllite deposits produce acid mine drainage by the oxidation of weathering. Compared to the fresh host rocks, the ores and altered rocks of pyrophyllite deposits produce acidic solution which contain higher amount of heavy metals because of their lower buffering capacity to acid solution.
The pHs of mine water and nearby stream water of pyrophyllite deposits are 2.1∼3.7, which are strongly acidic and much lower than that (6.2∼7.2) of upstream water and than that (6.8∼7.6) of the stream water derived from the non-mineralized area. This study reveals that this acid mine drainage can affect the downstream area which is 8km far from the pyrophyllite deposits, even though the drainage is diluted with abundant non-contaminated river water. This suggests that not only acid mine drainage but also the sulfide-bearing sediments originated from the pyrophyllite deposits move downstream and form acidic water through continuous oxidation reaction.
The heavy metals such as Pb, Zn, Cu, Cd, Ni, Mn and Fe are enriched in the mine water of low pH, and their contents decrease as the pH of mine water increases because of the influx of fresh stream water. Soils of the pyrophyllite deposits are characterized by high contents of heavy metals. The stream sediments containing the yellowish brown precipitates formed by neutralization of acid mine drainage occur in all parts of the stream derived from the pyrophyllite deposits, and the sediments also contain high amounts of heavy metals. In summary, the acid mine drainage of the pyrophyllite deposits is located in the upstream part of Hoidong water reservoir in Pusan contains large amounts of heavy metals and flows into the Hoidong water reservoir without any purification process. To protect the water of Hoidong reservoir, the acid mine drainage should be treated with a proper purification process.
It is necessary to quantitatively asses the influence of tidal currents to analysis the coastal current patterns before or after constructing offshore structures like as breakwaters. This assesment can be made through the use of simulation models designed to reproduce the water movements of the area. And it is very important to predict a phenomenon of pollutant dispersion in the area. In this study, in order to predict the changes of sea water quality for the port development plan, Ilgwang harbour, located at the east coast of Pusan, the numerical computations ere carried out. The flow patterns were investigated before and after the development of the harbour bay and coastal area connected on it. The computational models are an extension of earlier work on the flow which used the ADI Method(Alternating Direction Implicit Method) in appling to Osaka Bay by KANEKO et al. The transport of pollutant constituents depends upon the currental characteristics of the water-transporting medium. In the currental flow model, water velocities and water levels are computed throughout the regions of it. These value are then used in the mass-balance equation to obtain the pollutant-constituent transport. As a result of this research, the present water quality of Ilgwang harbour and the coastal areas connected on it was proved out some good condition. The changes of sea water quality due to the port development plan of the Ilgwang harbour bay and the coastal area were not large compared with the present condition, but it will be likely able to get worse by increasing the semi-enclosed areas in the harbour bay. In order to improve the water quality of the area after development, the method to activate tidal.
Water pollution in a semi-enclosed sea area such as a bay due to stagnancy of water has been a serious water environmental problem. Recently, some kinds of new methods to activate the tidal exchange between an inner bay and an outer sea area by control of a tidal residual current have been proposed. However, these methods have several problems, that is, I). deterioration in a natural view due to building of huge structures, II). increase of risk of a navigation in case of a submerged structure, III). limition of sea area where a tidal current can be controlled and IV). difficulty in removing those structures incase of occurrence of an unexpected impact on water environment. In this paper, a new method is proposed, which can solve all the above problems, to purify water quality in a semi-enclosed bay by creation and control of a pattern of a tidal residual current. The tidal residual current is controlled by unsymmetric structures, which change the properties of resistance according to the direction of flow, arranged on the sea bottom. In this study, several numerical and hydraulic experiments of tidal current and particle-tracking for various arrangements of bottom roughness in a semi-enclosed model bay were carried out. As a result of experiments, it becomes clear that it is possible to generate a new tidal residual current and to activate a tidal exchange by only operation of bottom roughness arrangement.
낙동강 유역에서 수질예보시스템의 개발을 위해서 신뢰도해석 기법에 기초한 QUAL2E-AFOSM모형을 개발하였다. 왜관∼물금 구간에 대해 수리학적 부등류 해석을 실시하였고, 최적의 반응계수 추정을 위해 BFGS 기법을 사용하여 최적화 해석을 실시하였으며, 이를 기초로 하여 모형의 보정과 검증을 실시하였다. 추계학적 해석을 위하여 AFSOM 기법을 적용한 신뢰도 해석을 수행하였다. 상류단과 주요 지류에서의 수질, 유량과 반응계수에 대한 변동성을 고려하였다.