• 한국환경과학회지
• /
• 제21권11호
• /
• pp.1349-1360
• /
• 2012

This study presented the phytoplankton communities of the three lakes (Sayeon, Daeam, Hoeya ) using for drinking water in the Ulsan reservoir. The water storage of the Lake Sayeon, Daeam and Hoeya were 25, 13, 21 million ton respectively and most of which were being utilized for industrial and residential purposes. The total precipitation of the Ulsan region in 2010 was 1,162 mm, decreasing 10 % from 1,275 mm of the annual. As for pollutant loads, BOD and TN discharge loads of Daeam was the highest with 3,277 kg/day, 1,931 kg/day and 90 % of them were came from non-point pollutant sources. TP discharge loads showed the highest in the lake Hoeya with 643 kg/day and 97 % of them were came from point sources as household, industry and livestock. We assessed water quality of the lake Sayeon, Daeam and Hoeya using 17 variables. The water quality assessment found that the lake Daeam met the fourth to fifth grade because of high concentration of COD, SS and chlorophyll-a. Eutrophication assessment was conducted by revised Carlson's Index (TSIm, Aizaki) and found that Lake Daeam was more eutrophicated than the other two lakes all the year through as for chlorophyll-a, transparency and the total phosphorus (TP). A total of 95~111 phytoplankton species were identified from the three lake samples. Among them, the largest number of species were Chlorophyceae with 35~51, followed by Bacillariophyceae with 36~45, Cyanophyceae with 9~11, and Cryptophyceae with 6~9 species. The total cell number of phytoplankton was the highest in February (15,254 cells/mL) with Bacillariophyceae in the lake Daeam and the seasonal succession shows that Bacillariophyceae (Stephanodiscus spp.) in the spring, Cyanophyceae (Anabaena spp.) in the summer and the autumn, Bacillariophyceae (Stephanodiscus spp.) in the winter.

• 생태와환경
• /
• 제44권4호
• /
• pp.396-406
• /
• 2011

2010년 2월부터 2010년 10월까지 울산 지역에 위치한 선암저수지, 대암호, 사연호, 회야호 4개 호소에 대하여 각 호소 내의 수질 및 저서성대형무척추동물상 조사를 수행하였다. BOD는 평균 $14.2\;mg\;L^{-1}$로, 4개 호소 중 선암저수지에서 연간 편차가 가장 컸으며, 회야호를 제외한 모든 호소에서 2월에 최대값, 5월에 최소값을 나타냈고, 회야호는 7월에 최소값을 나타냈다. 영양염 항목은 평균 TN $0.051mg\;L^{-1}$, TP $0.100mg\;L^{-1}$, $NH_3-N\;0.606mg\;L^{-1}$, $NO_3-N\;0.014mg\;L^{-1}$로, TN 항목은 4개 호소에서 6월에 최대값을 나타냈고, TP는 3월에 최대, 5월에 최소값을 나타냈다. 저서성대형무척추동물은 4월과 10월에 조사를 수행하였으며, 평균 TN 및 $NO_3-N$ 농도가 $0.082mg\;L^{-1}$, $0.023mg\;L^{-1}$로 가장 높았던 선암저수지에서 총 36종 평균 208 inds. $m^{-2}$로 가장 많은 종이 출현하였고, 대암호 21종 59 inds. $m^{-2}$, 회야호 17종 125 inds. $m^{-2}$, 사연호 16종 58 inds. $m^{-2}$가 출현하였다. 영양염 항목과 저서성대형 무척추동물 종수의 상관관계 분석 결과, 울산 지역 내 4개 호소에 서식하는 저서성대형무척추동물 종수는 해당 호소의 연평균 TN 농도와의 상관계수 0.962 (P<0.05), $NO_3-N$ 농도와의 상관계수 0.999 (P<0.05)로, 종수는 TN과 $NO_3-N$에 대해서 양의 상관관계를 보이는 것으로 조사되었다.