설악산 국립공원의 어류분포

장민호,조가익,하진용,정광석,박성배,주기재 한국어류학회 2002 韓國魚類學會誌 Vol.14 No.4

설악산 국립공원지역 산간계류의 17개 지점에서 2000년 6월부터 2001년 6월까지 어류상 및 이화학적 요인을 계절별로 총 4회에 걸쳐 분석하였다. 모든 조사지점은 1~3차의 하천으로 비교적 물리·화학적 교란이 적었으며 하천폭은 5~30 m 정도였다. 채집된 어류는 총 18과 42종 2,557개체였고, Cyprinidae는 16종으로 84.7%의 상대풍부도를 나타냈으며, Gobiidae 4종, 5.0?의 상대풍부도를 보였다. Cyprinidae는 전체 채입종의 37.2%를 나타냈다. 우점종은 Zacco temminck로 10개 지점에서 738개체가 채집되어 28.9%의 상대풍부도를 나타냈으며, 아우점종은 Rhynchocypris kumkangensis와 Z. platypus로 각각 4개 지점 648개체(25.3%)와 7개 지점 344개체(13.5%)로 나타났다. 한국고유종(Korean endemic species)은 모두 4과 11종 781개체로 30.5%의 상대풍부도를 나타냈으며, 고유화 빈도는 25.6%로 한국의 평균 고유화 빈도와 유사하게 나타났다. 본 조사에서 외래어는 채집되지 않았다. 국립공원 내에 서식하는 어류의 다양성 유지와 회복을 위해서는 공원 내는 물론 경계지역 하천의 체계적인 관리가 요구된다. The fish fauna of mountain streams in the Seorak National Park area was investigated from June 2000 to June 2001 (4 times). All 17 sites were relatively undisturbed 1st to 3rd order streams. A total of 2,557 individuals were collected and classified into 17 families and 43 species. Cyprinidae accounted for 37.2% (16 species) of the total fish species and 84.7% (2,165 ind.) of the total abundance. Subdominant families were Gobiidae (4 species, 5.0%) and Balitoridae (3 species, 3.4%). Zacco temmincki (RA 28.9%, 10 sites) dominated. Subdominant species were Rhynchocypris kumkangensis (25.3%, 4 sites) and Zacco platypus (13.5%, 7 sites). Eleven of the species are endemic to Korea (4 families, 30.5%). Exotic species were not collected in this survey. Fish diversity was higher in streams around the boundary area than in the national park. Therefore, management of streams in the boundary area to protect the fish biodiversity can be efficiently conducted. Habitat degradation should be reduced for the conservation and restoration of fish diversity.

LIMNOLOGY AND CONSERVATION OF THE TRISTATE OXBOW WETLAND ( OHIO , INDIANA )

(Gea Jae Joo) 강원대학교 환경연구소 1996 한 일 지방간 생태공학적 수질개선 공법에 관한 Symposium 논문집 Vol.- No.-

Conservation of Tristate Oxbow wetland(Ohio, Indiana), U.S.A : Strategies, status, and concerted efforts by privat and public agencies

Gea-Jae Joo and David A. Francko 江原大學校 附設 環境硏究所 1992 環境硏究 Vol.9 No.-

Influences of flooding events on the limnology of riverine wetlands

Joo, Gea Jae 경북대학교 환경과학연구소 1995 環境科學論文集 Vol.9 No.1

미국 알라바마에서 지질학적으로 다른 두 하천의 Alkaline Phosphatase 활성도

Joo, Gea-Jae,Ward, Amelia K. The Ecological Society of Korea 1995 Journal of Ecology and Environment Vol.18 No.1

Alakline phosphatase activity (AP A) as a phosphorus deficiency measurement in flowing waters and of microhabitats (rocks, wood, leaves, and sediments) was measured and its relationship to flux of nutrients and response to rainfall events were determined for two geologically different streams in west Alabama from August to November. Results indicated water column AP A in both streams had a low correlation with levels of orthophosphate, total organic phosphorus, nitrate, ammonia, dissolved organic carbon, and discharge (r=0.075-0.583; n=g-IU. Communities on rock surfaces showed a higher AP A level than those on wood and leaves. Sediment passed through a $106{\mu}m$ sieve showed 2-9 times higher AP A level than material passed through $425{\mu}m$ sieve. The first storm after drought at Yellow Creek introduced substantial quantities of DOC (2.5 times baseflow concentrations) and $N0_3-N$ (5.8 times baseflow concentrations) which did not affect AP A significantly. The second storm at Little Schultz Creek caused minor changes in nutrient cocentrations; however $N0_3-N$ levels and AP A were drastically lower due to the dilution effect. Retention of stream water AP A at Yellow Creek and Little Schultz Creek on $0.45{\mu}m$ filter (54 and 43%, respectively) and $0.22{\mu}m$ (83 and 77% of total APA. respectively) indicated more free dissolved portion of the enzyme was present at Little Schultz Creek. Little Schultz Creek (with carbonate and with a higher productivity and biomass) showed a consistantly greater AP A activity $(132{\pm}54\;{\mu}M{\cdot}1^{-1}{\cdot}min^{-I};\;n=g)$ than Yellow Creek $(41{\pm}23\;{\mu}M{\cdot}1^{-I}{\cdot}min^{-I}$, with a sandstone substrate; n=l1, $p{\leq}O.OO1)$. Overall, a greater APA on all microhabitats and the presence of more dissolved enzyme in Little Schultz Creek during the study period may indicates it is more P deficient than Yellow Creek.

Influences of Flooding Events on the Limnology of Riverine Wetlands

Joo, Gea Jae 경북대학교 환경과학연구소 1995 環境科學硏究所論文集 Vol.9 No.1

Long - Term Trend of the Eutrophication of the Lower Nakdong River

Gea Jae Joo,Hyun Woo Kim,Kyong Ha,Jwa Kwan Kim 한국하천호수학회 1997 생태와 환경 Vol.30 No.5

N/A Acceleration of eutrophication has been observed in the lower Nakdong River since the early 1980s. A longer hydrologic retention time due to the estuary dam construction and high nutrient input were the cause of an increase in phytoplankton biomass. Trophic status (chl. a) changed from meso-eutrophic (28±23㎍/l, 1982-87, n=26) to hypertrophic (58 ±148㎍/l, 1993-98, n=236) with frequent bloom developments. Elevated BOD, COD, and nutrient levels were observed (before 1987: 3.6±0.8mg/l, after 1987: 4.6 ±2.4 BOD, 4.4±1.2 to 8.1 ±2.6 COD, 0.9 ±0.8 to 2.3 ±1.0 NO_3-N, 2.4±0.9 tO 3.7±1.7TN, respectively). Along With the eutrophication Process in the river, phytoplankton community structure has been shifted (Microcystis bloom in summer and Stephanodiscus bloom in winter). Microzooplankton (rotifers) were the dominant group and they appeared to play an important role in regulating phytoplankton biomass. Hydrologic influence on the water quality at the lower part of the river has to be evaluated in spring and fall when discharge is generally low. Evaluation of point and non-point pollutant leadings of entire river basin is urgently needed for the systematic reduction of nutrient inputs.

The Application of an Algal Fence for the Reduction of Algal Intake into the Water Intake Facility

Joo, Gea-Jae,Jang, Min-Ho,Park, Sung-Bae,Jung, Jong-Mun,Roh, Jae-Soon,Jeong, Kwang-Seuk 한국육수학회 2003 생태와 환경 Vol.36 No.4

본 연구에서는 상수원수 취수장의 취수구로 유입되는 조류 군체의 양을 물리적으로 억제할 수 있는 조류 펜스를 개발하고, 현장에 적용 및 평가하였다(2001년 6-9월). 펜스를 설치한 후 펜스 안팎의 식물플랑크톤 생체량은 통계적으로 유의한 차이를 나타내었다. 분산 분석의 결과 설치 1일 후의 chl.α는 모든 수심(0,1,2m)에서 유의한 차이를 보였으며(모든 수심에서 0.001>p, 각 수심별 n=16), 특히 표층과 수심 1m에서 가장 큰 차이를 보였다. 하지만 조류 저감 효과는 설치 후 3-5일이 지나면서 감소하였다. 조류 펜스의 물리적 유입 저감 효과의 지속성 유지를 위해서는 효과적인 설치 및 유지관리 방안(예, 기계적인 설치 및 주기적인 역세척 등)이 모색되어야 하며, 생태 모형을 이용하여 대번성 시기 예측이 가능할 경우 훨씬 효과적으로 조류의 유입 차단이 가능할 것으로 보인다. In this study, an algal fence was developed and applied to reduce the input of algal scum into the water intake facility. The effectiveness of vertical algal fences (overlapped three types of meshes, (312㎛×375㎛, 390㎛×450㎛, and 0.7㎝×1㎝; vertical depth, 1.5m; length of fence, about 120m)) was experimentally tested at a water intake facility(Mulgum, lower Nakdong River). The application of the fence resulted in the statistically significant difference of algal biomass between inside and outside of the fence. According to ANOVA test, chl. a concentration in day-1 showed large difference at each depth of 0, 1, 2m(0.001>p at each depth, n=16 respectively). Especially large difference was observed at 0 and 1 m depth. However, the fence was only effective for a short period and its efficency declined by D-5 after the installation. When better maintenance options for the fence are prepared, e.g. mechanical installation and periodic backwashing of the fence, the performance of algal fence may be sustained. In addition, reliable models for bloom prediction are required to provide an advanced indication of the optimal timing for the installation so that effective operation would be achieved.

Limnological Characteristics and Influences of Free-floating Plants on the Woopo Wetland during the Summer

( Gea Jae Joo ),( Gu Yeon Kim ),( Sung Bae Park ),( Chan Woo Lee ),( Sang Ho Choi ) 한국하천호수학회 2002 생태와 환경 Vol.35 No.4

본 연구는 하계동안 습지 수면을 덮고 있는 부유성 수생식물이 습지생태계에 미치는 영향을 알기 위하여 1998년 1월부터 1999년 10월까지 우포습지의 이·화학적 변화를 파악하고 하계에 부유수생식물 및 저토가 수질에 미치는 영향을 현장실험을 통하여 평가하였다. 우포습지의 수위는 홍수발생 시 낙동강의 범람으로 2-3m 정도의 변화를 보였다. 대부분이 이·화학적 요인들 및 동·식물플랑크톤의 밀도는 여름동안의 홍수와 6월에서 10월까지 습지 수표면을 거의 덮고 있는 수생 식물에 의해 많은 영향을 받는 것으로 나타났다. 용존산소(Jun.-Sept., 4.5±2.5 ㎎/ℓ; Oct.-May, 8.1±4.0 ㎎/ℓ)와 pH(Jun.-Sept., 6.9±0.4; Oct.-May, 7.4±0.8)는 다른 계절에 비해 여름철에 현저히 낮았다. 여름철에 번성하는 부유성 수생식물(개구리밥, 생이가래, 좀개구리밥)과 수중의 저토가 하계의 육수학적 특성이 미치는 영향을 파악하기 위하여 수표면에 enclosure(100 L, 6개)를 설치하고 부유식물, 천 그리고 노출 상태의 처리군을 부유식물의 유·무, 수중 저토의 유·무에 대해 실험한 결과, 부유식물이 있는 처리군이 다른 경우에 비하여 DO, pH가 낮게 나타났고, 노출된 대조구에서 상대적으로 식물플랑크톤(chl. a)의 생체량이 높았다. 또한 각 처리군에서 수중 저토가 있는 경우 영양염류농도가 높았고, 특히 부유식물이 있는 처리구에서 높은 영양염류의 농도를 보였다. 동물플랑크톤 군집의 변화는 부유식물에 의한 뚜렷한 영향은 보이지 않았지만, 초기에 rotifer가 우점하였고, 이후 cladoceran과 copepoda의 증가로 rotifer의 밀도가 급격히 감소하였다. 결과적으로, 조사기간 중 하계에 지속적으로 관찰된 DO와 pH가 감소하는 것은 수생부유식물의 번성과 수중 퇴적물의 분해에 따른 영향인 것으로 나타났다. During January 1998-October 1999, the impact of free-floating plants(FFP) on limnology of the wetland ecosystem was evaluated through the investigation of physico-chemical characteristics of the Woopo Wetland along with in situ manipulation experiments of aquatic plants. Flooding events occurred in the wetland during the summer period(Jun.-Aug.) and water levels rose to 2-3m due to precipitation from the catchment and inflow from the main channel of th Nakdong River. Physico-chemical parameters and plankton dynamics in the wetland during the summer were greatly influenced by floods and growth of free-floating plants. Dissolved oxygen(Jun.-Sept., 4.5±2.5 ㎎/ℓ; Oct.-May, 8.1±4.0 ㎎/ℓ) and pH(Jun.-Sept., 6.9±0.4; Oct.-May, 7.4±0.8) levels were significantly lower during the summer than any other seasons. Three types of enclosure experiments(100 L, treatments with floating plants, screened and opened) were conducted under the presence and absence of sediment for 15 days in the 1999 summer. The treatments with sediment had higher levels of nutrient concentrations than those of the others. Among the treatments with sediment, nutrient concentrations in the treatments with free-floating plants were higher than the others. Zooplankton communities in each treatment showed a similar variation, although the scale of zooplankton densities differed. Rotifer community dominated the zooplankton at the initial phase of the experiment, but decreased drastically along with an increase of cladoceran and copepod communities. In conclusion, low levels of dissolved oxygen and pH in the Woopo Wetland during the summer seemed to be caused by a proliferation of free-floating plants and active decomposition process at the bottom of the sediment.

Vertical Distribution of Zooplankton in the Regulated River (Nakdong River)

( Gea Jae Joo ),( Kwang Seuk Jeong ),( Hyun Woo Kim ),( Kwang Hyeon Chang ) 한국하천호수학회 2002 생태와 환경 Vol.35 No.4

Vertical distribution of zooplankton was studied in a regulated river system. Monthly samples were collected at the lower Nakdong River(Mulgum, above 27㎞ from the estuary barrage) from May to September in 1999. Zooplankton species and abundances were unevenly distributed in the water column. Among small rotifers, Polyarthra and Keratella were densely distributed at upper(0.5m) and mid layer(2m) while the density of Asplanchna was often higher at lower layer(3.5n). Cladocerans also showed heterogeneous vertical distribution patterns and their distribution was seasonally different. The occurrence of zooplankton patches was noted as similar to those commonly reported from lakes and reservoirs. The factors leading to the establishment of such distribution patterns was briefly discussed.