• 한국수산과학회지
• /
• 제49권5호
• /
• pp.665-670
• /
• 2016

A three-dimensional ecological model (EMT-3D) was used to simulate the behavior of PFOA in Gwangyang Bay, Korea. The results of sensitivity analysis showed that partition rate, adsorption rate, and settling rate were important factors in the variation in PFOA in particulate organic matter. Bioconcentration was the most significant factor for PFOA in phytoplankton, with the largest effect size. These parameters must therefore be carefully considered when modeling PFOA behavior. In simulations, 30% and 50% reductions in loads from land-based sources of PFOA resulted in concentrations of dissolved PFOA lower than 4 ng/L and 2 ng/L, respectively, in the central part of the bay.

• 환경영향평가
• /
• 제20권3호
• /
• pp.349-356
• /
• 2011

This research is aim to analyze of changing landscape and according to phenological cycle from image information of coastal environment obtained by multi-media were analyzed by camera and satellite image. The digital camera and satellite image were used for tidal flat vegetation monitoring during the construction of Sihwa lake. The vegetation type and phenological cycle of Sihwa tidal flat have been changed with the Sihwa lake ecosystem. The environment changes of Sihwa tidal flat area and ecological change were analyzed by field work digital camera images and satellite images. The airborne, UAV and satellite images were classified with the changed elements of coastal ecological environment and tidal flat vegetation monitoring carried out the changed area and shape of vegetation distribution with time series images.

• 한국환경생태학회지
• /
• 제34권4호
• /
• pp.282-293
• /
• 2020

본 연구에서는 2009-2019년 기간 동안 대전시 외곽의 도심개발에 따른 인근 하천(관평천)의 상류, 중류, 하류의 구간에서 4회 조사(2009, 2010, 2016, 2019)를 통해 이화학적 수질, 어류 종 조성, 생태 건강성 특성에 대해 장기간 변화추이를 분석하였다. 본 하천지역에서 도심개발은 2008년에 이루어졌고, 2012년에는 하천복원사업이 수행되어 하천복원 전과 후의 특성변화 추이를 모니터링 하였다. 하천 생태건강도 평가를 위해 군집수준의 어류평가지수(Fish Assessment Index, FAI)를 이용하였고, 어류의 기관(Organ) 수준에서 해부학적 건강도(Necropsy-based Health Assessment Index, HAI) 분석을 실시하였다. 이화학적 수질 분석에서는 중류(St. 2)에서 가장 낮은 탁도와 엽록소(Chl-a)가 측정되었다. 이는 빠른 유속에 의한 물리적 요인 때문으로 나타났다. 어류 조사에서는 총 18종이 채집되었고, 피라미(Zacco platypus)가 가장 우점 하는 종(40.6%)으로 나타났다. 하천복원 직후(2016)에는 민감종(Sensitive species)과 충식종(Insectivore species)이 우점, 종 다양도 및 종 풍부도 지수 상승, 생태건강도 지수(FAI)가 상승하여 생태 건강도는 "최상상태(A: 87.5)"로 나타났으나 가장 최근 조사인 2019년에는 전 기간에 비해 악화되는 것으로 나타났다. 기관(Organ) 분석에 의거한 해부학적 건강도 지수(HAI) 분석에 따르면, 피부손상(Skin)은 상류에서, 신장 손상(Kidney)은 하류 역에서 나타났고, 간(Liver)과 아가미(Gill)의 손상은 모든 지점에서 나타나 해부학적 측면의 건강도에서도 영향을 받는 것으로 나타났다.

• 한국환경생태학회지
• /
• 제30권1호
• /
• pp.39-47
• /
• 2016

한반도에 서식하는 노루의 계통분류학적 위치는 아직까지 명확하게 정리되어 있지 않으며, 최근까지 내륙과 제주도 지역에 서식하는 노루 간 외부형태와 유전학적 차이가 있다고 여러 차례 보고되고 있다. 따라서 본 연구는 외부형태와 유전적으로 차이가 나타나 두 아종으로 여겨지는 내륙과 제주도 노루의 머리뼈 특성에 있어서도 차이가 있을 것으로 생각하고, 그 차이를 비교 분석하여 한국노루의 분류학적 위치를 좀 더 명확하게 규명하고자 실시하였다. 총 50개체의 성체 노루 머리뼈를 비교 분석한 결과 머리뼈최대길이, 뒤통수뼈관절융기-치조점사이길이, 머리뼈바닥길이, 머리뼈최대폭, 광대뼈사이폭, 눈확사이폭, 얼굴길이, 위어금니열길이 등에서 유의한 차이가 나타나 제주노루가 내륙노루 보다 머리뼈의 크기 및 형태가 작은 것으로 나타났다. 두개골의 형태는 노루 아종 간 차이를 결정하는 중요한 요소이며, 위도, 경도, 고도에 직접적인 영향을 받지는 않지만 이 요소들이 1차 생산자에 영향을 미쳐 먹이식물에 변화를 가져오고 노루의 먹이 선택과 연관되어 순차적으로 두개골 형태에도 영향을 미친다. 따라서 한반도에 서식하는 노루 두개골의 계량형태학적 특성을 비교 분석한 결과 내륙 노루는 아종인 C. p. tianschanicus와 비슷한 반면, 제주 노루는 시베리아노루 3아종 및 유럽노루와 확연한 차이를 나타냈다. 이상의 결과를 종합해 볼 때 제주도 지역에 서식하는 노루의 경우 제주도에만 서식하는 고유종으로 아종 수준의 분류가 가능할 것으로 생각한다.

• Journal of Ecology and Environment
• /
• 제34권2호
• /
• pp.167-174
• /
• 2011

Black-billed magpies (Pica pica) are a highly sedentary species due to their short and round wings, which are not adequate for long distance flights. We investigated geographic variation in the vocal signals of magpies residing in South Korea and Japan (subspecies sericea). Based on the magpie's limited dispersal ability, we predicted that the variation in vocal signals of black-billed magpies could be explained by geographic barriers such as mountain ranges and straits. We analyzed four-syllable chatter calls of magpies from five localities in South Korea, which are separated by mountain ranges (Seoul, Daejeon, Daegu, Gwangju, and Busan), and two island localities separated from the mainland by straits (Jeju in Korea and Saga in Japan). We found significant differences in the characteristics of magpie chatter calls recorded in the seven localities, and the variation pattern was independent among the variables. Mainland-island differentiation and north-south differentiation were observed. In general, magpies on Saga were the most distinctive. North-south differentiation was observed among the Korean mainland localities. However, the pattern was not related to the presence of putative geographic barriers. We hypothesize that the patterns of geographic variation in the structure of magpie chatter calls residing in South Korea might have been shaped by a sudden expansion of magpies followed by low level of local isolation, which may have led to vocal differentiation. Along with elucidating the vocal environment of Korean magpie populations, more extensive sampling is needed to clarify the functional aspects of geographic variation in the vocal signals of Korean magpies.

• Animal Bioscience
• /
• 제37권8호
• /
• pp.1474-1482
• /
• 2024

Objective: The experiment aimed to determine the standardized ileal digestibility (SID) of crude protein (CP) and amino acids (AA) in 10 brown rice samples fed to pigs, and to construct predictive models for SID of CP and AA based on the physical characteristics and chemical composition of brown rice. Methods: Twenty-two cannulated pigs (initial body weight: 42.0±1.2 kg) were assigned to a replicated 11×3 incomplete Latin square design, including an N-free diet and 10 brown rice diets. Each period included 5 d adaptation and 2 d ileal digesta collection. Chromic oxide was added at 0.3% to all the diets as an indigestible marker for calculating the ileal CP and AA digestibility. Results: The coefficients of variation of all detected indices for physical characteristics and chemical composition, except for bulk weight, dry matter (DM) and gross energy, in 10 brown rice samples were greater than 10%. The SID of CP, lysine (Lys), methionine, threonine (Thr), and tryptophan (Trp) in brown rice was 77.2% (62.6% to 85.5%), 87.5% (80.3% to 94.3%), 89.2% (78.9% to 98.9%), 55.4% (46.1% to 67.6%) and 92.5% (86.3% to 96.3%), respectively. The best prediction equations for the SID of CP, Lys, Thr, and Trp were as following, SID_CP = -664.181+8.484×DM (R² = 0.40), SID_Lys = 53.126+6.031×ether extract (EE)+0.893×thousand-kernel volume (R² = 0.66), SID_Thr = 39.916+7.843×EE (R² = 0.41), and SID_Trp = -361.588+4.891×DM+0.387×total starch (R² = 0.85). Conclusion: Overall, a great variation exists among 10 sources of brown rice, and the thousand-grain volume, DM, EE, and total starch can be used as the key predictors for SID of CP and AA.

• Journal of Forest and Environmental Science
• /
• 제28권3호
• /
• pp.158-169
• /
• 2012

Sabah has experienced a rapid decline in the extent of forest cover. The precise impact of habitat loss on the conservation status of the plants of Sabah is uncertain. In this study we use the niche modelling algorithm MAXENT to construct preliminary, revised and final ecological niche models for Dipterocarpus lamellatus and Dipterocarpus ochraceus and combined these models with data on current land-use to derive conservation assessments for each species. Preliminary models were based on herbarium data alone. Ground surveys were conducted to evaluate the performance of these preliminary models, and a revised niche model was generated from the combined herbarium and ground survey data. The final model was obtained by constraining the predictions of the revised models by filters. The range overlap between the preliminary and revised models was 0.47 for D. lamellatus and 0.39 for D. ochraceus, suggesting poor agreement between them. There was substantial variation in estimates of habitat loss for D. ochraceus, among the preliminary, revised and constrained models, and this has the potential to lead to incorrect threat assessments. From these estimates of habitat loss, the historic distribution and estimates of population size we determine that both species should be classified as Critically Endangered under IUCN Red List guidelines. Our results suggest that ground-truthing of ecological niche models is essential, especially if the models are being used for conservation decision making.

• 한국해양공학회지
• /
• 제22권5호
• /
• pp.75-82
• /
• 2008

As a basic study for establishing a countermeasure for an oxygen deficient water mass (ODW), we investigated the variation of ODW volume according to the enforced total pollution load management in Jinhae Bay. This study estimated the inflowing pollutant loads into Jinhae Bay and predicted the reduction in ODW by using a sediment-water ecological model (SWEM). The result obtained in this study are summarized as follows: 1) The daily average pollutant loads of COD, SS, TN, TP, DIN, and DIP inflowing into Jinhae bay in 2005 were estimated to be about 12,218 kg-COD/day, 91,884 kg-SS/day, 5,292 kg-TN/day, 182 kg-TP/day, 4,236 kg-DIN/day, and 130 kg-DIP/day. 2) The calculated results of the tidal current by the hydrodynamic model showed good agreement with the observed currents. Also, an ecological model well reproduced the spatial distribution of the water quality in the bay. 3) This study defined the ODWDI (ODW decreasing index) in order to estimate the ODW decreasing volume caused by a reduction in the inflowing pollutant loads. As a result, the ODWDI was predicted to be about 0.91 (COD 30% reduction), 0.87 (COD 50% reduction), 0.79 (COD 70% reduction), 0.85 (ALL 30% reduction), 0.66 (ALL 50% reduction), and 0.45 (ALL 70% reduction). The ODW volume was decreased 1.5 $\sim$ 2.6 times with a reduction in the COD, TN, and TP inflowing pollutant loads compared to a reduction in just the COD inflowing pollutant load. Therefore, it is necessary to enforce total pollution load management, not only for COD, but also fm TN and TP.

• 환경영향평가
• /
• 제19권1호
• /
• pp.91-97
• /
• 2010

The systematic data management system in the area of river flow analysis has not yet constructed, even though the need is evident due to the complicated process of tremendous input/output data in the modeling study and the importance of visualization of spatial flow variation. The objectives of this study are to suggest the method for analysis of changing river sections affecting ecological habitat characteristics. The effects of ecological habitat characteristics are assessed with respect to changing river sections. A GIS special analysis is created representing in the past section of Nonsan-river using historical data. Topographic surfaces are subject to erosional and depositional forces that a specific set of surface characteristics unique to elevation data. GIS spatial analyst is used to generate surface grids from historical point data. Using the GIS spatial analyst can be constructed sections for anywhere of river. The change of depth between 1979 and 1988, the left bank elevations of a river are increased about 1.5m. But the right bank elevations of a river are decreased about 2.3m caused by erosion. In addition, the change of spatial between 1988 and 2002, the regions of a river from upper stream to midstream are decreased the elevation. But the downstream regions are increased the elevation. These changes are analyzed in GIS program to assess methods for affecting ecological habitat.

• The Korean Journal of Ecology
• /
• 제20권5호
• /
• pp.323-328
• /
• 1997

The monoterpenoids are analysed in leaves and fallen leaves of Pinus species (P. thunbergii, P.. rigida. P. densiflora.). The amount of total monoterpenoids of P. thunbergii was always the highest, and then those of P. rigida and P. densiflora were orderly decreasing (P<0.05). The major monoterpenoids of P. thunbergii, P. rigida and P. densiflora are ${\beta}-pinene$, comphene and sabinene. There was no significant difference among the seasonal variation in monoterpenoids composition (P>0.05), but the concentrations of fenchone and bornyl acetate were varied (P<0.05).