• Asian-Australasian Journal of Animal Sciences
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• v.2 no.3
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• pp.284-286
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• 1989

• Journal of The Korean Society of Agricultural Engineers
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• v.47 no.2
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• pp.15-21
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• 2005

This study is to trace the change of stream shape using the past series of aerial photographs, and to compare the land use changes of riparian area along the stream. For the Gyeongan national stream, aerial photographs of 1966, 1981 and 2000 were selected and ortho-photographs were made with interior orientation and exterior orientation, respectively. Apparent changes of the stream were found that the consolidated reaches of stream by levee construction became straight together with widening of their stream widths. Especially the stream width of inlet part of Paldang lake widened almost twice because of the rise of water level by dam construction in 1974. The land use of riparian areas of three selected years were classified into six categories (water, forest, agricultural land, urban area, road, sandbar) by digitizing method. The forest and agricultural lands decreased and urban area increased as the stream maintenance had been performed.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.1300-1304
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• 2008

The fact that soil loss causing to increase muddy water and devastate an ecosystem has been appearing upon a hot social and environmental issues which should be solved. Soil losses are occurring in most agricultural areas with rainfall-induced runoff. It makes hydraulic structure unstable, causing environmental and economical problems because muddy water destroys ecosystem and causes intake water deterioration. One of three severe muddy water source areas in Soyanggang-dam watershed is Jawoon-ri region, located in Hongcheon county. In this area, many cash-crops are planted at illegally cultivated agricultural fields, which were virgin forest areas. The purpose of this study is to estimate soil loss with current land uses (including illegal cash-crop cultivation) and soil loss reduction with land use conversion from illegal cultivation back to forest. In this study, the Sediment Assessment Tool for Effective Erosion Control (SATEEC) ArcView GIS system was utilized to assess soil erosion. If the illegally cultivated agricultural areas are converted back to forest, it is expected to 17.42% reduction in soil loss. At the Jawoon-ri region, illegally cultivated agricultural areas located at over 30% and 15% slopes take 47.48 ha (30.83%) and 103.64 ha (67.29%) of illegally cultivated agricultural fields respectively. If all illegally cultivated agricultural fields are converted back to forest, it is expected that 17.41% of soil erosion and sediment reduction, 10.86% reduction with forest conversion from 30% sloping illegally agricultural fields, and 16.15% reduction with forest conversion from 15% sloping illegally agricultural fields. Therefore, illegally cultivated agricultural fields located at these sloping areas need to be first converted back to forest to maximize reductions in soil loss reduction and muddy water outflow from the Jawoon-ri regions.

• Magazine of the Korean Society of Agricultural Engineers
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• v.23 no.4
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• pp.41-45
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• 1981

This study is to be surveyed the rural environmental conditions such as housing, water works, sewerage, road and farm road, land utilization, natural conservation and sightseeing, public damage and disaster, and rural water requirement through the 50 villages (10995 home unit) The brief results summarized in this study are as follows. 1.Modernization of rural housing, toilet room and arrangement of dust materials are getting better than before l0yrs. 2.Water works are highly improved but sewerage problem is still in the serious problems. 3.Rood achievement is quite good but farm road is in still insufficiency 4.Utilization of land resources should be maximaized but land conservation is still insufficient condition and farm land is getting polluted. 5.Natural environmental conservation is much more improved but landscape is still insufficient. 6.Public damages such as water pollution, air pollution, and others are getting greater and greater but meteorological damage should be decreased. 7.Watershed condition is getting better and better but because of the large requiriment of the water use for the crops, agricultural water use should be needed much more than before l0yrs.

• Journal of Soil and Groundwater Environment
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• v.23 no.1
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• pp.92-105
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• 2018

In this study, the projected land use area in 2030 for major crop production was estimated in Jeju Island using land cover map, and corresponding agricultural water demand for 40 sub-regions was quantitatively assessed using the future climate change scenario (RCP 4.5). Estimated basic unit of water demand in 2030 was the highest in the western region, and the lowest in the eastern region. Monthly maximum agricultural water demand analysis revealed that water demand in August of 2030 substantially increased, suggesting the climate of Jeju Island is changing to a subtropical climate in 2030. Agricultural water demand for sub-region in 2030 was calculated by multiplying the target area of the water supply excluding the area not in use in winter season by the basic unit of water demand, and the maximum and minimum values were estimated to be $306,626m^3/day$ at Seogwipo downtown region and $77,967m^3/day$ at Hallim region, respectively. Consequently, total agricultural water demand in Jeju Island in 2030 was estimated to be $1,848,010m^3/day$.

• Korean Journal of Environmental Agriculture
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• v.28 no.1
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• pp.1-8
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• 2009

This study was aimed at assess environmental conservation functions by analyzing the change of land use areas in agricultural fields between 1999 and 2006, and comparing land surface temperature distribution between 1994 and 2006 in Yongin city. Land use maps of Yongin city were obtained from soil maps for 1999, Quickbird satellite images(less than 1 m) and parcel map for 2006. The land use area for Yongin city was in the order of forest > paddy field > upland > residence & building in 1999, and forest > residence & building > paddy field > upland in 2006. Decrease of paddy and upland fields reduced 34% and 41% of the capability of agricultural multifunctionality as to environment including flood control, groundwater recharge, and air cooling. Land surface temperature(LST) was derived from Landsat TM thermal infrared band acquired in September of 1994 and 2006 and classified into three grades. The results impplied that green vegetation in agricultural field and forest play an important role to reduce land surface temperature in warm season.

• Korean Journal of Environment and Ecology
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• v.22 no.6
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• pp.632-639
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• 2008

This paper deals with feeding site distribution aspect and seasonal distribution change of the wintering geese in Cheonsu bay and reclaimed area from October 2006 to March 2007. Geese were distributed mostly in agricultural land(rice field) during day time. According to the distribution map by maximum counts, observed geese of agricultural land were frequently distributed in large agricultural land. Especially, Geese were more used agricultural land near the reservoir where used as roosting site than the other sites. Diurnal feeding site of the geese were agricultural land near the reservoir with huge flock during early wintering season(October), but geese were used the agricultural land far from reservoir after mid wintering season(after January). The feeding flock size of Geese were decreased and feeding site was more far from the reservoir than in mid wintering season during late wintering season(March). Habitat use rate of the quadrat area where below 1km from the reservoir was most high in early wintering season. Contrary, habitat use rate where 2km far from the reservoir was shown lowest habitat use rate in early wintering season, but it was increased during mid wintering season(January) and decreased after mid wintering season. Habitat use rate of the agricultural land where 2km below and 1 km far from reservoir was shown middle rate, but it was increased until November and decreased after November. This result shown that feeding site preference of the wintering geese was affected by distance from roosting site(reservoir), and feeding site was changed as a food sources decreasing by stay time of geese flock.

• Journal of The Korean Society of Agricultural Engineers
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• v.53 no.6
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• pp.75-84
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• 2011

The objective of this study is to evaluate the hydrologic impacts of climate and land use changes in a rural small watershed. HadCM3 (Hadley Centre Coupled Model, ver.3) A2 scenario and LARS-WG (Long Ashton Research Station - Weather Generator) were used to generate future climatic data. Future land use data were also generated by the CA-Markov (Cellular Automata-Markov) method. The Soil and Water Assessment Tool (SWAT) model was used to evaluate hydrologic impacts. The SWAT model was calibrated and validated with stream flow measured at the Baran watershed in Korea. The SWAT model simulation results agreed well with observed values during the calibration and validation periods. In this study, hydrologic impacts were analyzed according to three scenarios: future climate change (Scenario I), future land use change (Scenario II), and both future climate and land use changes (Scenario III). For Scenario I, the comparison results between a 30-year baseline period (1997~2004) and a future 30-year period (2011~2040) indicated that the total runoff, surface runoff, lateral subsurface runoff, groundwater discharge, and evapotranspiration increased as precipitation and temperature for the future 30-year period increased. The monthly variation analysis results showed that the monthly runoff for all months except September increased compared to the baseline period. For Scenario II, both the total and surface runoff increased as the built-up area, including the impervious surface, increased, while the groundwater discharge and evapotranspiration decreased. The monthly variation analysis results indicated that the total runoff increased in the summer season, when the precipitation was concentrated. In Scenario III, the results showed a similar trend to that of Scenario II. The monthly runoff for all months except October increased compared to the baseline period.

• Journal of Environmental Science International
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• v.19 no.6
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• pp.779-785
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• 2010

To solve a problem of water supply on urban areas, groundwater recharge has to be assessed not only for evaluating the possibility of groundwater development but also for identifying a sustainable aquifer system for water resource development. The assessment of groundwater recharge has been challenged since the land use has been changed constantly. In this study, the groundwater recharge and its ratio were assessed from 1961 to 2007 in Su-yeong-gu, Busan, South Korea by analyzing precipitation, land use, and soil characteristics. For land use analysis, the urbanization change was considered. The land use areas for the residential, agricultural, forest, pasture, bare soil, and water in 1975 occupy 18.6 %, 30.0%, 48.8%, 0.1%, 2.0%, and 0.5% of total area, respectively. The land use ratios were sharply changed from 1980 to 1985; the agricultural area was decreased to 18.3%, and the residential area was increased to 15.0%. From 1995 to 2000, the agricultural area was decreased to 5.5%, and the residential area was increased to 5.4%. The annual averages of precipitation, groundwater recharge, and its ratio were 1509.3 mm, 216.0 mm, and 14.3% respectively. The largest amount of the groundwater recharge showed in 1970 as 408.9 mm, comparing to 2138.1 mm of annual rainfall. Also, the greatest ratio of the groundwater recharge was 19.8% in 1984 with 1492.6 mm of annual rainfall. The lowest amount and ratio of the groundwater recharge were 71.9 mm and 8.0% in 1988, relative to 901.5 mm of annual precipitation. As a result, it is concluded that rainfall has increased, whereas groundwater recharge has decreased between 1961 and 2007.

• Journal of Biosystems Engineering
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• v.12 no.3
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• pp.62-72
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• 1987

The necessity of using land on slopes for agricultural production has been recognized all arable land resources in plains are decreased. Mechanization is one of the main factors determining the extent of cultivating slope lands and it must be considered as a means of increasing labor productivity. This article discussed some relevent aspects of farm mechanization on slopes. It includes the potential slope land resources which can be tilled for food and forage productions, design characteristics of agricultural machines for use in slope lands, and possible solutions of the problems to be encountered in the mechanization process.