• Korean Journal of Remote Sensing
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• v.37 no.5_1
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• pp.1199-1206
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• 2021

Accordingly, attention is also being paid to the agricultural use of remote sensing technique that non-destructively and continuously detects the growth and physiological status of crops. However, when remote sensing techniques are used for crop monitoring, it is possible to continuously monitor the abnormality of crops in real time. For this, standard growth information of crops is required and relative growth considering the cultivation environment must be identified. With the relationship between GDD (Growing Degree Days), which is the cumulative temperature related to crop growth obtained from ideal cultivation management, and the vegetation index as standard growth information, compared with the vegetation index observed with the spectralreflectance sensor(SRS_NDVI & SRS_PRI) in each rice paddy treated with standard cultivation management and non-fertilized, it was quantitatively identified as a time series. In the future, it is necessary to accumulate a database targeting various climatic conditions and varieties in the standard cultivation management area to establish a more reliable standard growth information.

• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1225-1234
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• 2023

The intensity of crop water stress caused by moisture deficit is affected by growth and heat conditions. For more accurate detection of crop water stress state using remote sensing techniques, it is necessary to select vegetation indices sensitive to crop response and to understand their changes considering not only soil moisture deficit but also heat conditions. In this study, we measured the MERIS terrestrial chlorophyll index (MTCI) and chlorophyll/carotenoid index (CCI) under drought and heat wave conditions. The MTCI, sensitive to chlorophyll concentration, sensitively decreased on non-irrigation conditions and the degree was larger with heat waves. On the other hand, the CCI, correlated with photosynthesis efficiency, showed less sensitivity to water deficit but had decreased significantly with heat waves. After re-irrigation, the MTCI was increased than before damage and CCI became more sensitive to heat stress. These results are expected to contribute to evaluating the intensity of crop water stress through remote sensing techniques.

• Journal of Wetlands Research
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• v.26 no.1
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• pp.82-91
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• 2024

In this study, research cases related to blue carbon storage were collected and analyzed, and various definitions of blue carbon were considered in terms of spatiotemporal scope and scientific aspect. 444 papers were selected as research cases related to blue carbon storage, and analysis of the number of papers published by year/country and keywords was performed. Publication of papers related to blue carbon storage has continued to increase since 2011, and more than 50 papers have been published annually since 2018. The most publications by country were in Australia with more than 100 papers, and the United States and China also published more than 60 papers. Key terms related to "natural environment" and "storage characteristics" were analyzed in the sentences defined in the 23 papers that presented the definition of blue carbon. The natural environments where blue carbon was stored were mostly mangroves, salt marshes, and seagrass beds, and blue carbon repository included sediments and even plants themselves. The existing definition of blue carbon focused on the vegetation environment as the storage environment for blue carbon. However, since blue carbon is stored in the sediments of coastal wetlands, it would be appropriate to define the coastal ecosystem, including non-vegetated mudflats, as the storage environment for blue carbon.

• Korean Journal of Remote Sensing
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• v.40 no.3
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• pp.275-284
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• 2024

Monitoring crop growth changes and water content is crucial in the agricultural sector. This study utilized drones equipped with Short Wavelength Infrared (SWIR) sensors, sensitive to moisture changes, to observe soybeans' growth and water content variations. We confirmed that as soybeans grow more vigorously, their water content increases and differences in irrigation levels lead to decreases in vegetation and moisture indices. This suggests that waterlogging slows down soybean growth and reduces water content, highlighting the importance of detailed monitoring of vegetation and moisture indices at different growth stages to enhance crop productivity and minimize damage from waterlogging. Such monitoring could also preemptively detect and prevent the adverse effects of moisture changes, such as droughts, on crop growth. By demonstrating the potential for early diagnosis of moisture stress using drone-based SWIR sensors, this research suggests improvements in the efficiency of large-scale crop management and increases in yield, contributing to agricultural production.

• Journal of The Korean Society of Grassland and Forage Science
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• v.11 no.4
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• pp.236-243
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• 1991

A field experiment was conducted during the growing season of 1985 to determine the effects of slope orientation, north and south facing exposures and three different altitudes, 800, 1,000 and 1,200m a.s.1. on the dry matter yield, forage quality and botanical composition of alpine pasture. 1. Total dry matter yield of alpine pasture was influenced by slope orientation and altitude. An average forage yield of both exposures at 1,000m a.s.1. was 9,301kg/ha compared with 10,274kg/ha at 800m a.s.1. and the productivity express in relative percentage decreased by 9.5% per 200m attitudinal increase. 2. An average forage yield of both altitudes, 800 and 1,000m a.s.1. on the south facing exposure was 21.5% higher than that on the north exposure. 3. Crude protein concentration of forage grown on both exposures was lowest at 800m a.s.1. increasing gradually as the altitude increased, but crude fiber concentration decreaced in a manner opposite to that of crude protein. 4. Forage grown on the north facing exposure had a higher concentration of crude protein than that grown on the south facing exposure at the same altitude, but lower concentraion of crude fiber. 5. Orchardgrass and timothy were two main species on both exposures at 800m a.s.1. but timothy was only dominant species at 1,000 and 1,200m a.s.1. and performed well up to 1,200m a.s.1. in alpine area. The economic production limit of orchardgrass would be about 800m a.s.1. in the alpine pasture. 6. No soil property differences were found between the north and south facing exposures as well as three different altitudes in the alpine pasture. It seemed that the previous pasture fertilization of the experimental field completely overshadowed any soil property differences from slope orientation and altitude.

• Korean Journal of Environment and Ecology
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• v.22 no.6
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• pp.609-615
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• 2008

The study was conducted to analyze vegetation and soil characteristic of Corylopsis coreana population in Baekunsan of Gyeonggi-Do, Jirisan, Baekunsan, Jogaesan of Jeollanam-do, and Geumsan of Gyeongsangnamdo. Field research was from September 2005 to September 2006. According to classification with phytosociological method, the Corylopsis coreana population was classified into Tilia amurensis dominant population, Lindera erythrocarpa dominant population, and Pinus densiflora dominant population. According to CCA ordination, the Tilia amurensis dominant population were located in area of high elevation, and high concentration in total nitrogen, available phosphorous, and cation exchangeable capacity(CEC). The Pinus densiflora dominant population were located in area of low elevation, and low concentration in total nitrogen, available phosphorous, and cation exchangeable capacity. The Lindera erythrocarpa dominant population were located in area of high elevation, and medium concentration in total nitrogen, available phosphorous, and cation exchangeable capacity.

• Korean Journal of Environment and Ecology
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• v.22 no.5
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• pp.514-520
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• 2008

The permanent monitoring plots were installed in 2001 for long-term monitoring the structure of forest communities at the Piagol(Valley) and Daeseonggol(Valley) in the Jirisan National Park, and monitored the forest structure in the studied sites in 2001 and 2006. Dominant species at Piagol and Daeseonggol was Carpinuslaxiflora and Quercus mongolica respectively. Based on the distribution of major species' stem diameter, the species diversity index was higher in Piagol than that of Daeseonggol. The distribution of diameter in major tree species in the studied sites showed a stable plant community structure. The forest of Piagol, which is positioned in the valley, showed a quite a different composition of species from that of Daeseonggol, which is positioned on the slope. In the last five years, the overall grows rate of Piagol Forest decreased by $6.4m^2$ per hectare, while Daeseonggol Forest increased by about $8.27m^2$ per hectare. I think that this is because of the fact that a lot of large old trees have died.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1661-1665
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• 2006

In a natural river, cross sections of a channel vary according to inner or outer parts of meandering. Generally, depth of outer parts is deeper than that of inner parts. This kind of cross section change by meandering can be demonstrated by Beta distribution. The objects of this research is a 3D simulation of primary and secondary flow in the meandering natural channel. FLOW-3D program, a numerical model using CFD technique, and LES method was used for this research. 3D simulations were conducted in the channels having Beta distribution cross sections which have beds of mortar, gravel and vegetation. Two types of water stages and discharge were applied to each channel. In this research, primary flows are located in the outer parts of a top of bend and secondary flows rotate in the bottom on outer parts.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.319-323
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• 2009

최근 대체수자원 개발, 도시 비점오염과 물순환 체계의 효율적 관리를 위한 분산식 빗물관리기술에 대한관심이 급증하고 있다. 이수 목적의 빗물이용시설, 치수목적의 우수유출 저감시설, 택지개발사업의 재해저감시설 등 다양한 목적으로 시설들이 도입되고 있다. 그러나 치수용 시설에 있어 설계강우에 따른 홍수량 산정방법을 제외하고는 이수 및 물순환 건전화를 위한 계획, 설계기술은 현재까지도 부족한 실정이다. 특히 이수목적의 경우 집수면의 토지이용 특성, 용도별 사용수량 및 경제성에 대한 검토 없이 집수면적이나 대지면적의 일정비율 이상을 설계하고 있는 실정이다. 본 연구에서는 국내에서의 빗물관리시설 계획 설계를 지원하기 위해 공동주택 빗물관리 의사결정지원 모형(RainCity v1.5 Beta)을 개발하였다. 강우자료는 5분 간격의 설계강우, 시우량 및 일 강우자료를 DB나 사용자 파일로부터 호출하도록 하였으며, 토지이용 특성에 따라 유출계수를 고려한 수문학적 집수면적을 산정하여 적용하였다. 현재 버전은 이수 및 치수용 저류조, 침투통, 침투트렌치, 침투블럭 등 장치형 침투시설과 투수성포장 등 지표면 침투시설을 대상으로 하였으며, 각 시설조합의 설치에 따른 유입/유출량, 침투량 및 사용수량 등 물순환 과정을 모의할 수 있다. 특히 선택된 시설조합은 규모 시나리오에 따라 목표 기능에 맞는 시설규모들을 선정하고, 비용-편익분석을 통해 경제적인 시설규모를 결정할 수 있다. 향후 지속적으로 GUI를 개선하여 사용자 편의도를 높이고, 식생형 침투도랑, 생태연못, 중수이용시설과의 연계 등 기능을 확대할 계획이므로 국내에서의 빗물관리시설의 계획 설계 시 활용도가 높을 것으로 기대된다.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.1 s.108
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• pp.71-80
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• 2005

In order to search for ecologically indicative characteristics on the street tree plots in Daegu area, plant communities and their floras were investigated. A total of 105 plots were collected and numerically analyzed by PCoA(Principal Coordinates Analysis). These plots were classified into 4 types containing 139 species, 97 genera, 42 families(including 37 exotic species): urban-dry type, urban-wet type, rural-dry type, rural-wet type. Habitat connectivity to the surrounding vegetation cover, extent and frequency of human impacts, and soil moisture recognizably were the main factors to allow the plots differentiation. Indicative species composition to these four types was generated as Eleusine indica-Eragrostis multicaulis-Oxalis corniculata to the urban-wet, Digitaria ciliaris-Eleusine indica-Eragrostis multicaulis to the urban-dry, Setaria viri-dis-Artemisia-Lactuca indica var. laciniata to the rural-wet, and Setaria viridis-Digitaria ciliaris-Erigeron canadensis to the rural-dry, respectively. Mean species number per plot for rural type was 2.5 times higher than for urban types. Street tree species representative to the rural-wet type is Zelkova serrata, which is a key species of potential natural vegetation in the alluvial land of Daegu area. Street tree plots were characterized by Eleusine indica showing the highest r-NCD value and also C4-assimilation grass plants. Views on the efficacy of the rural-wet type and the reinforcement of vegetation connectivity and soil moisture in rehabilitating street tree plots, are discussed.