• Korean Journal of Environmental Agriculture
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• v.27 no.4
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• pp.464-473
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• 2008

Winter migratory birds gather in paddy rice fields to feed shed rice grains. The Korean Ministry of Environment has practiced a policy program Contract on Paddy Field Management (CPFM) during winter fallow since 2002. This program starts with a contract between local governments and farmers, and the government pays a differential subsidy to farmers who finish spreading rice straw, cultivating barley, letting the whole rice plant without harvest, and submerging paddy fields for winter migratory birds. As more local governments have operated CPFM program, the total area on the contract and subsidy budget has increased yearly since 2002. This program could have its stable position as a successful policy by giving profits to farmers. With the program extended, the population of winter migratory birds has been greatly. For the evaluation of environmental performance of a policy, we analyzed this CPFM program by introducing some indicators in the form of Driving Force-State-Response Framework. The indicators were composed of 3 categorized indicators; the area of paddy land contracted under this program as 'driving force' indicator, population of birds, the number of bird species and the amount of feces as 'state' indicators, and the size of monetary support, the number of farmers or local governments participating, and public perception as 'response' indicators. The contract area of paddy field under CPFM could be a good biodiversity indicator reflecting potential performance of this policy measure in the light of its linkage to the population of winter migratory birds. And the share of CPFM land of the whole agricultural land might also be used as a useful indicator of policy evaluation for improvement of wildlife diversity. The 'state' indicators such as population of birds and the number of bird species could be matched to 'driving force' indicator, but the total CPFM area of each site could not reflect the effect of areas under different management practices. However, the amount of bird feces could reflect differences in environmental performance with management practices as 'state' indicators. The development of indicators indicating 'response' such as farmers' behavior, public perception, and policy makers' willingness is also needed to support a successful implementation and improvement of this policy measure with the development of 'performance' indicators integrating all these indicators.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.1
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• pp.71-82
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• 2015

Hyla suweonensis is an endemic species and is designated as the only endangered species I among amphibians in 2012 by the Ministry of Environment, however studies about its habitat are lacking. This study was carried out to analyze habitat of H. suweonensis based on the spatial information using Maxent (Maximum entropy model as a species distribution model. We detected 45 present points until 2013 and 10 environmental variables by literature review for the model. The results showed that $429km^2$ (0.95%) of the study area, which was about 7.75% of the total agricultural area, was high possible habitats of H. suweonensis. The habitat of H. suweonensis was analyzed by over $1km^2$ rice paddy fields that were lower elevations, flat slopes, and not fragmented. The distance from forests and rivers was identified as a factor that affects its habitat possibilities. In order to conserve H. suweonensis, a large area of rice paddy fields should be preserved, and especially the area around forests and rivers would be required more intensive management. In addition, to compensate for degraded habitats of H. suweonensis in urban areas like as Suwon city, considering integrated watershed management strategy could be effective in the perspective of ecological habitat network of H. suweonensis.

• Journal of the Korean earth science society
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• v.30 no.5
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• pp.622-629
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• 2009

This study intended to collect data for evaluating the meteorological value of Upo Wetland which is the largest wetland in the downstream of Nakdong River. The observations were conducted in summer at the Upo Wetland and its surrounding paddy field that is the converted areas from a wetland to a paddy field. The following results are obtained: 1) The temperature of Upo Wetland area was $1^{\circ}C$ lower than the surrounding area during the day while it was a little higher during the night.; 2) The maximum wind speed in the Upo Wetland area was 3.5 m/s which is stronger than 1.6 m/s of its surrounding area. The south wind was observed in the farmland for most of the day while north winds and south winds alternated between day and night in Upo Wetland.; 3) In heat budget analysis, Upo Wetland was wasted in the form of latent heat rather than sensible heat in daytime.

• Korean Journal of Agricultural Science
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• v.21 no.1
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• pp.67-80
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• 1994

Farm land is considered the most important production factor in farm production. Land is not only one of the most scarce resource but also the size of land holding is the key factor in determining the size of farm income in Korea. To increase farm productivity by accepting bio-chemical and mechnical technology, the qualitative improvement of farm land through land consolidation and on-farm development have been carried out by the Korean government. Land consolidation with water resource development makes possible the high-tech-capital intensive farming, internal expansion of farm land and hightening the rate of land intensity in connection with UR problems. This paper contained the present status of farm land base development, allocation of investment by types of farm land development and the econome-trical analysis on the effects of the investment on rice productivity during the past 27 years since 1965. The rate of irrigated paddy area had been increased from 42% in 1965 to 74% in 1991. Land consolidated area out of the total paddy area had been achieved 44.9% and the improved rate of poor drained paddy area was shown 43.5% in 1991. To carry out the above farm land base development projects, the government had procured financial budgets consisting of the G't subsidy, long term loan, foreign loan, the provincial G't subsidy, WFP counter fund and farmer's burden.

• Journal of Radiation Protection and Research
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• v.40 no.4
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• pp.231-243
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• 2015

Four different paddy soils collected around the Gyeongju nuclear site were treated with $^{99}TcO_4{^-}$ solution under the assumption of two contrasting contamination scenarios. Scenario I (SN-I) is for a pre-transplanting deposition of $^{99}Tc$ followed by plowing, whereas SN-II is for its deposition onto the water surface shortly after transplanting. Rice plants were grown in lysimeters in a greenhouse. Plant uptake of $^{99}Tc$ was quantified with the $TF_{area}$ ($m^2{\cdot}kg^{-1}-dry$). The SN-II $TF_{area}$ values for straws and brown rice, having been generally higher than the SN-I values, were within the ranges of $6.9{\times}10^{-3}{\sim}4.1{\times}10^{-2}$ and $5.2{\times}10^{-6}{\sim}7.3{\times}10^{-5}$, respectively. Sorption onto clay seems to have decreased $^{99}Tc$ uptake in SN-I, whereas it may have had an insignificant effect in SN-II. A phenomenon characteristic of submerged paddy soil, i.e., the development of a thin oxic surface layer may have greatly affected the rice uptake of SN-II $^{99}Tc$. The surface-water concentrations of $^{99}Tc$ were much higher in SN-II than in SN-I. For the percolating water, however, the opposite was generally true. At most 1.3% of the applied $^{99}Tc$ were leached through such percolation. The use of empirical deposition time-dependent $TF_{area}$ values was considered desirable in assessing the radiological impact of a growing-season deposition of $^{99}Tc$ onto paddy fields.

• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.2
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• pp.134-142
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• 1997

This study was performed to evaluate the drain runoff characteristics from one paddy field, and to provide the basic data required for the determination of flood discharge and unit drainage water for drainage improvement and farmland consolidation. For this purpose, under the assumption that drain discharge from paddy field was similar to outflow of reservoir, runoff model based on storage equation was applied to the experimental field, and simulated results were compared to the measured discharge at weir point. To estimate effective storage volume of paddy field with water depth, 4 regression formula were examined such as linear, exponential, power, and combined. From the observed runoff characteristics, it was shown to be 3.3~16.3${\ell}$/sec in weir discharge, 57.2~98% in runoff ratio, and relative error of simulated result was 3.0~39.4%, 8.5 ~56.0 % for peak flow and runoff ratio, respectively. Curve number by SCS method was calculated as mean value of 96.4 using measured rainfall and runoff data, it was considered relatively high because paddy field has generally flooding depth contrary to the upland watershed area.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.23 no.1
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• pp.60-63
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• 1978

The survey was carried out over an area representing about 29％ of the reclaimed paddy fields of west and south seashore in Korea. Scirpus maritimus L. was heavily infested all over the reclaimed paddy fields. But the weed was scarcely found in double cropping fields cultivating barley at paddy after rice or in reclaimed paddy fields where the cultivation was taken a long time.

• Korean Journal of Remote Sensing
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• v.31 no.1
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• pp.11-20
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• 2015

This study aimed to investigate the canopy growth conditions and the accuracy of phenological stages of paddy rice using ground-based remote sensing data. Plant growth variables including Leaf Area Index (LAI) and canopy reflectance of paddy rice were measured at the experimental fields of Chonnam National University, Gwangju, Republic of Korea during the crop seasons of 2011, 2012, and 2013. LAI values were also determined based on correlations with Vegetation Indices (VIs) obtained from the canopy reflectance. Three phenological stages (tillering, booting, and grain filling) of paddy rice could be identified using VIs and a spatial index (NIR versus red). We found that exponential relationships could be applied between LAI and the VIs of interest. This information, as well as the relationships between LAI and VIs obtained in the present study, could be used to estimate and monitor the relative growth and development of rice canopies during the growing season.

• Korean Journal of Agricultural Science
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• v.27 no.2
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• pp.141-157
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• 2000

This study is aimed at identifying the socio-economic value of the total area of 23,500ha of paddy field which will be reclaimed in year 2003. In Korea, tidal land reclamation projects has been carried out not only for paddy field expansion to meet national food security but also for national land expansion to cope with the shortage of land supply in implementing urbanization and industrialization. As of end of 1999, 75,738ha of tidal land reclamation, 48.3%, out of 156,666ha has been carried out in Korea. In spite of continuous implementation of tidal land reclamation, 48.3%, out of 156,666ha has been carried out in Korea. In spite of continuous implementation of tidal land reclamation projects, the appraisal of the national land expansion value has not been made even though the severe competitiveness of land use in economic development. Agricultural land about 20,000 - 30,000ha per year has been converted to urban and industrial land and the converted areas have been produced higher added value than that of the farm land. Accordingly, farm land expansion equivalent to the converted area have to be reclaimed to cope with the food shortage and security in the future. In relation to the study, demand and supply of rice, the staple food of Korean, has been projected up to year 2025. The study results are as follows: 1. Under the assumption of continuing the present tendencies of rice consumption, population increase, farming practices and farm land conversion, paddy area requirement to meet self sufficiency of rice were forecasted as 136,950ha in 2015, 193,460ha in 2020 and 218,482ha in 2025 respectively. 2. The average converted price of paddy per pyeong in Kimje city, Puna Gun and Gunsan city was estimated at 241,150won and average farm land price was amounted to 63,760won. The differential rent was estimated at 177,400won per pyeong which was used as a criteria for valuation of national land expansion effect of the tidal land reclaimed by Saemangeum project. The total land rent of 23,250ha expanded by tidal land reclamation was amounted to 12,361 billion won. Annual expected value of the expanded national land was estimated at 988.9 billion won considering 8% of annual discount rate in Korea. 3. Tidal land resource for paddy area development is limited comparing with the future requirement of paddy area to cope with self sufficiency of rice consumption. Accordingly farm land conversion to urban and industrial land should be regulated and protected in the sense of sustainable development in the future.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.94-94
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• 2022

최근 밀(Triticum aestivum L.) 소비량이 꾸준히 증가하고 있어 국내 밀 자급률 증대를 위한 노력이 필요하다. 그러나 우리나라는 작물을 재배할 수 있는 농경지가 한정되어 있어 벼 수확 후 휴경 논을 이용하여 겨울철에 밀을 재배하거나, 하계 소득 작물과 연계하여 겨울철에 밀을 생산할 수 있는 방안을 모색할 필요가 있다. 본 연구에서는 남부지역 평야지 논을 이용하여 밭작물 중심 다모작 작부체계를 제시함과 동시에 밀을 재배하여 생육 특성과 수확량 변화를 살펴보았다. 단위면적당 수수 및 종실 수량은 작부이력에 밭작물이 포함된 다년 다모작 작형(들깨-IRG-참깨-밀, 콩-IRG-참깨-밀)이 다년 벼-밀 이모작이나 벼-IRG-참깨-밀 다모작에 비해 많았으며, 특히 들깨와 콩이 포함된 작부체계에서 많았다. 밀 품종 간 비교에서는 금강밀이 조경밀에 비해 출수기와 성숙기가 2~3일 빨랐지만 종실 수량은 100 kg/10a 이상 적어, 동일한 환경조건에서 조경밀이 금강밀에 비해 곡물 생산성 측면에서 유리할 것으로 보인다. 더군다나 조경밀은 조숙 다수성 경질밀로 전국에 재배가 가능하고, 단백질 함량이 높고 강력분의 특성을 보여 제빵용으로 많이 활용되고 있다. 본 연구에서 조경밀은 단백질이 10% 이하로 낮고 아밀로스는 28.4%로 높은데 반해, 금강밀은 단백질이 11.0%로 높고 아밀로스는 26.6%로 낮아 제과·제빵에 있어서, 금강밀이 좀 더 유용할 것으로 보인다. 밀가루의 Falling number는 조경밀과 금강밀 모두 350초 이상으로 높아 수발아로 인해 전분의 분해가 일어나지 않은 건전한 상태의 곡립임을 알 수 있다. 그리고 gluten 함량도 조경밀과 금강밀 모두 유사하게 높았으며, gluten 지수는 금강밀이 좀 더 높았다. 이상의 결과를 토대로 밀 수확량을 증가시키기 위해서는 기존의 벼-밀 이모작 보다 들깨-IRG-참깨-밀이나 콩-IRG-참깨-밀 등의 다년 다모작 작형이 좀 더 유리할 것으로 보인다.