• 한국농림기상학회지
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• 제7권1호
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• pp.98-106
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• 2005

지하수는 복잡 경관에 위치한 광릉 산림 소유역의 물과 탄소 순환에 중요한 역할을 담당한다. 지하수가 지하 매질의 전기비저항(ER)에 크게 영향을 미치기 때문에, ER을 사용하여 지하수의 깊이와 지하 수분 함량을 조사할 수 있다. 따라서 최근 전기비저항 탐사를 통해 토양수분과 지하수 함양률, 수위변동을 측정하는 연구가 진행되고 있다. 정량적으로 적용할 수 있는 연구 결과가 나온다면 전기비저항 탐사가 다양한 시간과 공간규모의 물 수지의 닫힘을 확인하는 데에 중요한 기여를 할 수 있을 것으로 기대된다. 본 논문에서는 광릉 산림 소유역에서 지하수의 역할을 규명하기 위해 설치될 지하수 관정의 정확한 깊이와 위치를 파악하고자 실시한 ER 현지 조사의 예비 결과를 제시하였다 앞으로의 연구는 유용성이 입증된 전기비저항 탐사와 더불어 GPR 탐사, 전자탐사, 탄성파 탐사 등의 복합 물리탐사와 GIS를 이용한 분석을 통해 더 정확한 지하구조의 정보와 지하수공 최적의 위치를 추정할 수 있을 것으로 보인다.

• Journal of Forest and Environmental Science
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• 제38권3호
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• pp.141-151
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• 2022

Soil seed banks as natural storage of plant seeds play an important role in the maintenance and regeneration of watershed. Natural regeneration potential of the soil seed bank of Land use types (LUTs) in Ogun River watershed (ORW) was investigated. ORW was stratified using proportionate sampling technique into Guinea Savannah (GS), Rainforest (RF) and Swamp Forest (SF) Ecological Zones (EZs). Three LUTs: Natural Forest (NF), Disturbed Forest (DF) and Farmland (FL) were purposively selected in GS: GSNF, GSDF, GSFL; RF: RFNF, RFDF, RFFL and SF: SFNF, SFDF, SFFL, respectively. Systematic line transects was used in the laying of the sample plots. Sample plots of 25 m×25 m were established in alternate positions. Ten 1 m×1 m quadrats were randomly laid for soil core sampling from previously randomly selected ten plots. The core samples (10) were pooled per plot in each LUT and placed in individual trays. Ten trays with sterilized soil were used as control. The trays were watered regularly and checked for seedlings emergence fortnightly for 18 months. The experimental design used was 3×3 factorial experiments. ANOVA, Diversity index (H') and Similarity index (SI) were used to analyze the data. There was significant difference in seedling emergence among ecological zones and land use types (p<0.05). A total of 4,400 seedlings emerged from the soil samples. All species were distributed among 32 families. FL in the RF had the highest number of germinated seeds (705±37.33 seedlings) followed by DF in the RF (701±49.6 seedlings). The lowest emergence was in NF of the SF (199±28.41 seedlings). DF in the RF had highest number of species (34) distributed among 22 families. Emergence from soil seed bank of NF in ORW was generally with more of tree species than herbs that were predominant in FL and DF.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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• pp.204-207
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• 2008

The purpose of this study is to identify how much the MODIS NDVI (Normalized Difference Vegetation Index) can explain the soil moisture simulated from SWAT (Soil and Water Assessment Tool) continuous hydrological model. For the application, ChungjuDam watershed (6,661.3 $km^2$) was adopted which covers land uses of 82.2 % forest, 10.3 % paddy field, and 1.8 % upland crop respectively. For the preparation of spatial soil moisture distribution, the SWAT model was calibrated and verified at two locations (watershed outlet and Yeongwol water level gauging station) of the watershed using daily streamflow data of 7 years (2000-2006). The average Nash and Sutcliffe model efficiencies for the verification at two locations were 0.83 and 0.91 respectively. The 16 days spatial correlation between MODIS NDVI and SWAT soil moisture were evaluated especially during the NDVI increasing periods for forest areas.

• 한국환경복원기술학회지
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• 제23권6호
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• pp.137-149
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• 2020

This study was carried out to analyze the monthly runoff concentration on non rainfall days in order to prepare basic data to compare the runoff concentration on rainfall days in 7 forest watersheds in the Republic of Korea. Forest stream water has been collected through 15 times of sampling in each watershed and analyzed based on the changes in concentration of Biochemical Oxygen Demand(BOD), Chemical Oxygen Demand(COD), Total Organic Carbon(TOC), Total Nitrogen(TN), and Total Phosphorus(TP). The average concentration was 0.8 mg/L for BOD, 1.4 mg/L for COD, 0.8 mg/L for TOC, 1.85 mg/L for TN and 0.002 mg/L for TP during non rainfall days. Coniferous forested watersheds showed higher value of TN and TP concentration. Concentrations of BOD and TP in early March (p<0.01) were affected by melt water flow input in spring season. Significant differences (p<0.01) in concentrations were observed in BOD and TOC, indicating seasonal rainfall and vegetation growth impacts on forest stream quality. Concentration of TN and TP showed significant positive correlation, and weak negative correlation was found in the concentration of BOD and TOC. It is expected that result of forest stream water on non rainfall days could be basic information in managing non-point source from forest watersheds.

• 환경영향평가
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• 제11권3호
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• pp.117-127
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• 2002

This study tested the usefulness of landscape indices for quantifying forest fragmentation due to linear development projects. Research was carried out in the middle-upper Nakdong River watershed, which has been affected by the expressway building, or national road-widening. Landscape indices were calculated from the forest cover maps before and after road-building using FRAGSTATS 3.1. We could successfully demonstrate the forest fragmentation based on landscape indices; (1) patch size decreased, and edge density and patch density increased (2) roads simplified patch shapes, especially in the larger patches, (3) patch core area size decreased, and core area density increased, (4) the distance increased between the focal patch and each of the other patches within the search radius (=1km) as a result of roads. We suggest several important needs for future researches, including continued investigation of scaling issues, development of indices that measure specific components of spatial pattern, and study of the relationships between forest fragmentation and ecological processes.

• 한국물환경학회지
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• 제27권4호
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• pp.425-432
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• 2011

To control non-point source pollution at a watershed scale, rainfall-runoff characteristics from forest watersheds should be investigated since the forest is the dominant land use in Korea. Long-term monitoring would be an ideal method. However, computer models have been utilized due to limitations in cost and labor in performing long-term monitoring at the watersheds. In this study, the Geo-spatial interface to the Water Erosion Prediction Project (GeoWEPP) model was evaluated for its runoff prediction from a coniferous forest dominant watersheds. The $R^2$ and the NSE for calibrated result comparisons were 0.77 and 0.63, validated result comparisons were 0.92, 0.89, respectively. These comparisons indicated that the GeoWEPP model can be used in evaluating rainfall-runoff characteristics. To estimate runoff changes from a coniferous forest watershed with various cover degree scenarios, ten cover degree scenarios (10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%) were run using the calibrated GeoWEPP model. It was found that runoff increases with decrease in cover degree. Runoff volume was the highest ($206,218.66m^3$) at 10% cover degree, whereas the lowest ($134,074.58m^3$) at 100% cover degree due to changes in evapotranspiration under various cover degrees at the forest. As shown in this study, GeoWEPP model could be efficiently used to investigate runoff characteristics from the coniferous forest watershed and effects of various cover degree scenarios on runoff generation.

• 대한공간정보학회지
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• 제16권3호
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• pp.59-64
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• 2008

토양침식은 산악지역에서 산림조성에 중요한 문제를 일으키며 비옥한 토양을 침식시켜 식생의 성장을 저해시키며 인도에서 수집한 자료와 GIS를 이용하여 인도의 서부산맥 모야유역의 토양침식을 분석하였다. 주제도의 레이어로 산림, 지형경사, 배수 등에 대한 자료가 사용되었으며 토양침식 지도분석에서 48%의 지역이 중간정도의 침식을 보였다. 또한 35%지역은 높은 침식을 보였으며 가장 높은 침식은 식생지역의 7%를 차지하였다. 이러한 토양침식 분석도는 유역에서의 토양침식을 방지하기 위한 대책을 수립하는데 주요한 자료가 될 것으로 판단된다.

• 환경영향평가
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• 제15권4호
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• pp.259-270
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• 2006

The purpose of this study is to understand the relation between the land use status in watersheds and stream turbidity. Major water quality components (flow rate, turbidity, SS, BOD, TN, TP, etc.) of two streams (Jaun and Naerin) and the land use status for each correspondent watershed have been analyzed through the field sampling and the geographical overlaying of land use and watershed map. The detailed results of this study showed that; turbidity has been increased rapidly from 1.9 to 13.0 NTU for Jaun Stream, 0.4 to 0.7 NTU for Naerin Stream, due to the increased flow rate during the period of June. The agricultural area of the Jaun watershed was $13.5km^2$ (10.1% of the overall watershed), comparing to $2.0km^2$(1.4%) of upper watershed of Naerin stream. The forest was widely distributed along the 30m buffering zone from the center of Naerin stream, which comprised 64.14% of the whole watershed area. But in case of the Jaun, the ratio of forest was 17.84%, while the ratio of farming field was 30.33%.

• 한국농공학회논문집
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• 제51권5호
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• pp.69-78
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• 2009

In order to improve water quality of upper watershed of Paldang reservoir, it is necessary to evaluate non-point source pollution loads and identify critical watershed pollution sources. A GIS based Soil and Water Assessment Tool was applied to evaluate model application and reliability, estimate NPS pollution load, identify critical watershed by NPS pollution sources, and suggest various best management practices for Kyongan Stream watershed. Yearly NPS pollution loads were estimated 30.0% SS, 60.1% TN and 35.4% TP, respectably. The watershed pollution load is mainly decided by precipitation condition and SS and nutrients load have a significant regression relationship. Based on 10-year average yearly NPS pollution load, critical sub-watersheds were identified. The No. 5 and 17 which have lots of relatively intensive agricultural fields and scattered industrial area were vary critical sub-watersheds and under more intensive pollution load. In order to control critical watershed, watershed best management practices such as scientific fertilizer, contour farming and parallel terrace, transferring the sloppy farmland to grass or forest and constructing a buffer zone, and constructing wetlands and retention ponds will be applied. Overall the SWAT model can be efficiently used for identification of critical sub-watersheds in order to develop a priority watershed management plan to reduce water pollutions.

• 한국산림과학회지
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• 제85권2호
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• pp.280-287
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• 1996

강원대학교(江原大學校) 임과대학(林科大學) 부속연습림(附屬演習林)내의 임도밀도가 상이한 3유역(유역(流域) A : 6.67m/ha, B : 5.52m/ha 및 C : 미개설(未開設))의 산지급류하천을 대상으로 임도개설 전 후인 1994년 및 1995년의 강우량 변화에 따른 부유토사의 유출량 변화를 분석한 결과 다음과 같은 결론을 얻었다. 1. 일강우량(日降雨量)이 적은 5~6월 사이에는 1994년과 1995년 모두 일유출량(日流出量)이 $0.25{\times}10^4m^3/day$ 이하였으나, 호우기(豪雨期)인 7~8월에는 일강우량에 비례하여 강우기간 중에는 $5.0{\times}10^4m^3/day$ 이상을 나타내는 등 일유출수량은 일강우량의 증감에 민감하게 반응하였다. 그러나 일유출량이 $25{\times}10^4m^3/day$ 이상은 1994년에는 2회였으나, 1995년에는 7회로 강우량이 풍부하였다. 2. 부유토사량은 임도개설전의 일강우량(日降雨量) 74mm, 92mm 및 120mm와 임도개설후의 일강우량 21mm 및 47mm에는 3유역 모두 하천수(河川水) 규제기준인 25mg/l 이하였다. 그러나 192mm의 강우에는 C유역은 변화가 없었으나, A와 B유역의 평균 부유토사량은 1,525mg/l 및 775mg/l으로 하천수 규제기준의 61배 및 31배였으며, 강우종료후 35시간동안 지속적으로 유출되었다. 3. 최대부유토사량(最大浮遊土砂量) 역시 임도개설전의 강우와 임도개설후의 적은 강우에서는 하천수 규제기준 이하였다. 그러나 일강우량 192mm인 경우에 A, B유역의 최대부유토사량은 하천수 규제기준씩 526배와 108배인 13,150mg/l 및 2,690mg/l을 기록하여 토사유출에 따른 수질오염을 시각적으로 파악할 수 있었다. 이상과 같이 임도개설이 부유토사 유출에 크게 영향을 미치며, 특히 임도밀도가 높은 유역일수록 강우량이 증가함에 따라 다량의 토사가 유출되고 있음이 확인되었으므로 부유토사의 생산원(生産源)인 임도비탈면 보호를 위한 식생공(植生工) 및 토목공(土木工)은 물론 침사지(沈砂池)와 같은 방재시설(防災施設)에 대한 대책을 강구해야 할 것이다.