전 지구 물정보시스템의 구축과 활용

장민원,Jang, Min-Won 한국관개배수위원회 2010 한국관개배수회지 Vol.45 No.-

Mapping Paddy Rice Varieties Using Multi-temporal RADARSAT SAR Images

장민원,김이현,박노욱,홍석영 대한원격탐사학회 2012 大韓遠隔探査學會誌 Vol.28 No.6

This study classified paddy fields according to rice varieties and monitored temporal changes in rice growth using SAR backscatter coefficients (σ˚). A growing period time-series of backscatter coefficients was set up for nine fine-beam mode RADARSAT-1 SAR images from April to October 2005. The images were compared with field-measured rice growth parameters such as leaf area index (LAI), plant height, fresh and dry biomass, and water content in grain and plants for 45 parcels in Dangjin-gun, Chungnam Province, South Korea. The average backscatter coefficients for early-maturing rice varieties (13 parcels) ranged from -18.17 dB to -6.06 dB and were lower than those for medium-late maturing rice varieties during most of the growing season. Both crops showed the highest backscatter coefficient values at the heading stage (late July) for early-maturing rice, and the difference was greatest before harvest for early-maturing rice. The temporal difference in backscatter coefficients between rice varieties may play a key role in identifying early-maturing rice fields. On the other hand, comparisons with field-measured parameters of rice growth showed that backscatter coefficients decreased or remained on a plateau after the heading stage, even though the growth of the rice canopy had advanced.

EGIS 토지피복지도를 이용한 농어촌용수구역 불투수면적률 변화

장민원,김학관 한국농촌계획학회 2022 농촌계획 Vol.28 No.4

This study aimed to estimate the impervious area rate by rural water districts in 2009 and 2021 and analyze the changes. From the EGIS(Environmental Geographic Information Service) land cover maps, the impervious areas were defined as residential, commercial, industrial, culture⋅sports⋅recreational, traffic, public facilities, and greenhouses of land cover classes. For 496 rural water districts excluding the border area with North Korea, the nationwide impervious area rate increased from 5.96% in 2009 to 7.50% in 2021. The average of the top 50 rural water districts increased from 23.4% in 2009 to 27.1% in 2021. E ven for the bottom 50 rural water districts, the average impervious area rate rose from 1.12% in 2009 to 1.40% in 2021. Rural water districts with a high impervious area rate are mainly distributed in metro cities and industrial areas. The contraries are primarily found in Gangwon, Gyeongsang, and Jeolla regions covered with forests and farmlands. Notably, the impervious area rate changed more in the neighboring rural water districts than in large cities, and the rate kept increasing slightly even in rural areas with a low impervious area rate. The findings of this study will help prepare a reasonable alternative for managing the impermeable surface of rural areas for safe and sound rural water cycle

위성영상 및 항공사진을 활용한 시설재배면적의 시공간적 변화 유형 분석- 밀양 상남면과 삼랑진읍을 중심으로 -

장민원,조현경,김수진,백미경 한국농공학회 2020 한국농공학회논문집 Vol.62 No.6

This study analyzed the spatio-temporal change pattern of greenhouse areas for Sangnam-myeon and Samrangjin-eup of Miryang-si in Gyeongnam,which is one of major greenhouse area. First, in order to overcome the lack of statistical data of the distribution of greenhouses, aerial and satelliteimages were interpreted from 1987 to 2018, and the spatial distribution of the greenhouse parcels which has continuously increased was mapped basedon the digital cadastral map. Next, through the emerging hot spot tool in ArcGIS Desktop, the spatio-temporal change in transition from open-fieldto greenhouse cultivation was classified into 9 clusters. About 67.7% of the target area was categorized as a hot spot, and the p attern o f New hot spot,which were recently converted to greenhouse parcels, covered about 34.1%. While, about 11.3% of parcels were expected to keep the existing open-fieldcultivation practice for a while. Overall, the greenhouse parcels have been densely developed along a river and were lately expanding even to the farneighbor. It implied that, in the future, the competition of water intake among farms would be more serious and the environmental responsibility inconsideration of water quality as well as quantity would be getting strengthened due to increasing pollution loads and river intake.

논 관개 지역의 지하수위 관측을 통한 시공간적 지하수위 변동 특성 분석

장민원,박기욱,김성준,배승종,Jang, Min-Won,Park, Ki-Wook,Kim, Seong Joon,Bae, Seung-Jong 한국농공학회 2015 한국농공학회논문집 Vol.57 No.6

This study aimed to establish a field observation system for monitoring tempo-spatially precise changes of groundwater level and to analyze the impact of rainfall and irrigation practices on groundwater changes in paddy regions. The monitoring system comprising of all nine groundwater observation wells and four ponding depth sensors was installed in a part of paddy regions benefited from Gosam reservoir, Ansung-si. The result of grundwater level change during the irrigation period in 2002 was averagely 0.51 m higher than that during the non-irrigation period. In particular between March before puddling and June after transplanting, there was maximum 1.23 m rise in groundwater level. On the other hand, concerning the change in ponding depth, groundwater level changed similarly, and hourly rainfall was revealed to have better correlation with 24-hour delayed hourly groundwater level than with the corresponding groundwater level. Eventually, this study could be referenced for further studies to set up a more comprehensive and sustainable monitoring system of groundwater conditions.

농업가뭄에 대한 지역별 취약성의 평가 기술에 관하여 (GIS를 이용한 농업가뭄에 대한 지역 취약성 평가 기법의 개발)

장민원 한국농공학회 2004 韓國農工學會誌 : 전원과 자원 Vol.46 No.4

저수지 저수량 추정을 위한 위성 SAR 자료의 활용성

장민원,이현정,김이현,홍석영,Jang, Min-Won,Lee, Hyeon-Jeong,Kim, Yi-Hyun,Hong, Suk-Young 한국농공학회 2011 한국농공학회논문집 Vol.53 No.6

This study discussed the applicability of satellite SAR (Synthetic Aperture Radar) imagery with regard to reservoir monitoring, and tried the extraction of reservoir storage from multi-temporal C-band RADARSAT-1 SAR backscattering images of Yedang and Goongpyeong agricultural reservoirs, acquired from May to October 2005. SAR technology has been advanced as a complementary and alternative approach to optical remote sensing and in-situ measurement. Water bodies in SAR imagery represent low brightness induced by low backscattering, and reservoir storage can be derived from the backscatter contrast with the level-area-volume relationship of each reservoir. The threshold segmentation over the routine preprocessing of SAR images such as speckle reduction and low-pass filtering concluded a significant correlation between the SAR-derived reservoir storage and the observation record in spite of the considerable disagreement. The result showed up critical limitations for adopting SAR data to reservoir monitoring as follows: the inappropriate specifications of SAR data, the unreliable rating curve of reservoir, the lack of climatic information such as wind and precipitation, the interruption of inside and neighboring land cover, and so on. Furthermore, better accuracy of SAR-based reservoir monitoring could be expected through different alternatives such as multi-sensor image fusion, water level measurement with altimeters or interferometry, etc.

2008년 경남지역 가뭄현황과 원인

장민원 한국농공학회 2009 韓國農工學會誌 : 전원과 자원 Vol.51 No.1

기후변화 대응을 위한 양수장의 농업가뭄 취약성 실태 평가

장민원,김수진,배승종,유승환,정경훈,황세운 한국농공학회 2019 한국농공학회논문집 Vol.61 No.6

In order to implement practical alternatives to proactively cope with the agricultural drought, the potential vulnerability of irrigation pumping stationsto agricultural drought was quantitatively evaluated. Data for the 124 pumping stations which are correlatable to the three proxy variables, i.e. exposure,sensitivity, and adaptive capacity was collected by the Korea Rural Community Corporation, and then standardized considering distribution of each dataset. Finally, the vulnerability index was calculated by multiplying the weights determined by the expert survey. The results showed that the vulnerabilityindex ranged from 0.709 to 0.331 and the most vulnerable pumping stations such as Judam, Wongoo and Jinahn were mostly located in Gyeongbukprovince likely because of the climatological characteristics with high temperature and low rainfall around this area. In addition, it was found that theadaptive capacity was a dominant factor comparing to exposure or sensitivity proxy variables in contributing to the vulnerability. It is thereforerecommended that more practical alternatives should be employed to effectively reduce the vulnerability of an individual pumping station to agriculturaldrought. Furthermore, the corresponding data related to adaptive capacity should be systematically organized and managed at a field level to designreliable adaptation strategies.

시군단위의 불투수면적률과 도시화 지표의 상관성 분석

장민원,김현준,최윤희,김학관 한국농촌계획학회 2023 농촌계획 Vol.29 No.4

This study investigated the correlation between impervious surface area rate(ISAR) and various urbanization indicators at the si-gun administrative level. For the years 2017 and 2021, we built correlation matrices to examine the relationships between ISAR and eight urbanization indicators, including total population, working-age population, residential power consumption, non-agricultural power consumption, paved road length, permitted development area, numbers of registered vehicles, and cadastral ‘Dae’ parcel area. Additionally, K-means clustering was employed to classify the 229 si-guns based on the ISAR change patterns. The analysis revealed a significant positive correlation between ISAR and urbanization indicators for both years studied. However, the interannual comparison showed a noticeably weaker correlation between changes in ISAR and urbanization indicators from 2017 to 2021. The K-means analysis also showed that si-guns with higher ISAR values, typically urban areas, demonstrated a weaker correlation, while the cluster consisting mostly of rural areas with lower ISAR displayed stronger correlations. These results suggested that ISAR should be a significant factor for consideration in sustainable rural planning and development strategies.