• 한국환경과학회지
• /
• 제14권6호
• /
• pp.583-596
• /
• 2005

Samples of water, soil, and sediment were taken from 10 streams of Andong city in Gyeongbuk province in October 2004. To assess the degree of environmental pollution for each stream site, the chemical analyses of pollutants such as T-N, T-P, COD, heavy metal, organophosphorous and organochlorine pesticides, and dioxin-like PCB congeners were implemented using the standard process tests or the U. S. EPA methods. In addition, biological assessment using insect immune biomarkers was conducted on the same environmental samples to complement the chemical assessment. Except Waya stream (T-N; 2.91 mg/L, T-P; 0.16 mg/L, COD; 14.0 mg/L) with above the environmental quality standards, the T-P and COD concentrations of 9 sites are relatively low. The contents of Pb and Cd in samples taken from each stream were much lower than environmental quality standards. However, in comparison with soil samples of other streams, several times higher concentrations of Pb and Cd were found in locations at Mi, Gilan, Yeonha, and Waya stream sites. Dementon-S-methyl, diazinon, parathion, and phenthoate compounds among organophosphorous pesticides were detected as concentrations of ppb levels, respectively, from soil samples collected in the vicinity of Gilan, Mi, Norim, and Waya stream. On the other hand, 16 organochlorine pesticides and 12 dioxin-like PCB congeners selected in this study were not found in all samples. In particular, considering significant disrupting effects of Waya stream's samples on insect immune capacity, this stream seems to be contaminated with investigated and/or univestigated pollutants in this study.

• 환경생물
• /
• 제29권3호
• /
• pp.180-194
• /
• 2011

본 연구는 임하호 유역에 위치하는 반변천, 길안천과 낙동강에 총 8개 정점을 선정하여 2008년 9월부터 2009년 6월까지 물리-화학적 요인과 부착규조 군집과의 관계를 조사하였다. 부착 규조류는 총 120종류로서 2목, 3아목, 7과, 22속, 108종 및 12변종으로 구성되어 있다. 부착 규조 군집의 우점종은 Achnanthes alteragracillima, A. convergens, A. minutissima와 Fragilaria construens var. venter 등 4종류로 구성되어 있다. 부착 규조 군집과 물리-화학적 요인과의 관계(r)는 -0.94~0.97의 범위로 각요인에 대한 상관성의 범위가 넓었다. 물리적 요인인 탁도와 부착 규조 군집의 밀도, 종수 및 각 생물 지수 등과의 관계는 -0.25~0.18의 범위로서 화학적 요인보다 낮은 음 또는 양의 관계를 나타내었다. QHEI와 부착 규조 군집의 각 요인과의 관계는 -0.18~0.42의 범위로서 이 요인 역시 화학적 요인보다는 다소 낮은 음 또는 양의 상관성을 나타내었다. 물리적 서식지 (QHEI)와 부착 규조 군집과의 관계는 낮은 유의성을 나타내었다. TP와 DAIpo, TDI가 높은 상관성(r=0.79, 078)을 나타내므로 총인이 부착 규조군집에 영향을 미친 것으로 나타났다.

• 한국물환경학회지
• /
• 제37권5호
• /
• pp.369-380
• /
• 2021

In this work, we analyzed the effects of drought on the water temperature (WT) of Nakdong river basin major river sections using Standardized Precipitation Index (SPI) and WT data. The analysis was carried out on a seasonal basis. After calculating the optimal time scale of the SPI through the correlation between the SPI and WT data, we used the copula theory to model the joint probability distribution between the WT and SPI on the optimal time scale. During spring and fall, the possibility of environmental drought caused by high WT increased in most of the river sections. Notably, in summer, the possibility of environmental drought caused by high WT increased in all river sections. On the other hand, in winter, the possibility of environmental drought caused by low WT increased in most river sections. From the risk map, which quantified the sensitivity of WT to the risk of environmental drought, the river sections Nakbon C, Namgang E, and Nakbon K showed increased stress in the water ecosystem due to high WT when drought occurred in summer. When drought occurred in winter, an increased water ecosystem stress caused by falling WT was observed in the river sections Gilan A, Yongjeon A, Nakbon F, Hwanggang B, Nakbon I, Nakbon J, Nakbon K, Nakbon L, and Nakbon M. The methodology developed in this study will be used in the future to quantify the effects of drought on water quality as well as WT.