• KOMUNHWA
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• no.62
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• pp.3-28
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• 2003

The researches related to rice farming are still mainstream, although cultivation research has a new transition due to investigation of arable land since 1990s. The latter of 1990s, the interest of fields was increased after the large scale investigation

• Research in Plant Disease
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• v.9 no.3
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• pp.137-144
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• 2003

This study was conducted to clarify developmental characteristics of scab in potato fields in Jeju island, Korea from 1995 to 1999. Occurrence of potato scab increased with repeated cultivaton of potato and high soil pH in the fields. Incidence of the disease was high as 54.8％ in the repeatedly cultivated potato fields but relatively low as 20.8~26.3% in the non-cultivated fields and in the fields where barley and Chinese cabbage were formerly cultivated. A total of 66 isolates were obtained from the diseased patato tubers and identified as Streptomyces scabies, S.turgidiscabies and S. acidiscabies. The isolation frequency of each Streptomyces species was 37.7%, 14.8% and 18.0%, respectively. The optimum temperature for mycelial growth of the Streptomyces spp. was $28~30^{\circ}C$, and the optimum pH for that 6~7.

• Korean Journal of Plant Resources
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• v.20 no.4
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• pp.309-311
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• 2007

This study was conducted to select the most suitable fertilizer level on nursery of mat rush for good quality and high yield. $N-P_{2}O_{5}-K_{2}O=60-30-60$ (kg/10a), fertilizer level on nursery of mat rush showed relatively superior values for all yield components and quality with 57g in fresh weight, 12g in dry weight, 23% in air drying ratio for per plant at the nursery and 125cm in stem length, 150 numbers in stem number, 4,082kg/10a in fresh stem yield, 345kg/10a in long stem yield, 996kg/10a in medium stem yield, 1,421kg/l0a in total stem yield, 34% in dry stem ratio and 30% in long stem ratio at the main paddy field. The results indicate that fertilizer level, $N-P_{2}O_{5}-K_{2}O=60-30-60kg/10a$ in nursery shows different adaptabilities to a particular fertilizer level and 60-30-60 (kg/10a) seems to be the most suitable fertilizer level of mat rush for good quality and high yield.

• Korean journal of applied entomology
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• v.46 no.2
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• pp.221-227
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• 2007

Stink bug species and host plants occurred in fallow lands for rice product regulation were studied in Honam area from 2004 to 2005. A total of 26 bug species in 8 families were surveyed in the fallow lands. Population density of Cletus punctiger adult reached its peak in July and was higher in fallow lands close to mountain area in Muan. Population density of stink bug species occurred in plain area of Wanju were significantly low in 2004 and population density of C. punctiger adult reached its peak in July and August in fallow lands in 2005. Five species of stink bug including C. punctiger immigrated from fallow lands to rice fields in August, and three other species including Cletus schmidti in September. Eight stink bug species which were observed to feed on weeds in fallow lands were C. punctiger, C. schmidti, Eurydema gebleri, Pachygrontha antennata, Trigonotylus caelestialium, Aelia fieberi, Eysarcoris aeneus, and Nezara antennata.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.131-131
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• 2020

우리나라는 농산물시장개방이후 휴경면적의 증가, 농지전용, 도시화의 가속화, 시설작물 재배면적 변화 영향에 의한 논과 밭의 이용 패턴변화 등으로 농촌지역의 토지이용구조가 변화되어 왔다. 이는 곧 국내 토지이용패턴의 변화로 연결되고, 농업구조의 변화는 농촌경관, 농업용수 이용, 농촌지역 비점오염 물질 발생패턴의 변화를 야기할 것으로 예상되고 있다. 본 연구에서는 금강권역을 연구지역으로 하여, 농업지역의 토지이용변화 중 논 내 시설작물 재배면적 변화에 주안점을 두고 토지이용변화 예측모형인 CLUE-s(Conversion of Land Use and its Effects at Small regional extent) 모형을 이용하여 미래 농업지역의 토지이용변화를 예측하고자 하였다. CLUE-s 모형의 입력 자료로 국가수자원관리종합시스템(WAMIS)의 1980~2010년까지 5년 간격 토지이용 통계자료 및 환경부 2008, 2013년 중분류 토지이용 자료에서 금강유역을 추출하여 구축하였다. 모형의 입력자료를 위해 토지이용 항목을 총 7개(수역, 시가지, 논, 밭, 시설재배지, 산림, 초지)로 분류하고 특별토지이용 정책 자료로 농업진흥구역도 및 국토환경성 평가도를 이용하였다. 관측자료의 경향을 이용하여 환경부 중분류 토지이용 변화를 기준으로 농업지역(논, 밭, 시설재배) 변화에 대한 회귀식을 도출하였다. 본 연구의 결과를 활용하여 농업지역 변화에 따른 수문 및 수질의 영향을 파악하고 미래 토지이용 변화에 따른 농촌지역 비점오염 물질 발생패턴 등을 분석하기 위한 기초 자료로 활용할 것으로 판단된다.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.4
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• pp.59-68
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• 2016

The application of the Life Cycle Assessment (LCA) methodology to assess the environmental impact of rapeseed cultivation in winter fallow after harvesting rice was investigated and compared with barley cultivation in crop rotation system. Data for input materials were collected and analyzed by 1 ton rapeseed and barley as functional unit. For the Life Cycle Impact Assessment (LCIA) the Eco-indicator 95 method has been chosen because this is well documented and regularly applied impact method. From the comparison of impact categories such as greenhouse effect, ozone depletion, acidification, heavy metals, carcinogens, summer smog, and energy resources for 1 ton of final product, emission potential from rapeseed was higher than that from barley. The range from 65 to 96% of these potential came from chemical fertilizer. On the other hand, eutrophication potential from barley was higher than that from rapeseed, mainly came from utilizing the chemical fertilizer. During the cultivation of barley and rape, environmental burden by heavy metals was evaluated by 0.5 Pt, larger than points from other impact categories. The sum of points from all impact categories in barley and rapeseed was calculated to be 0.78 Pt and 0.82 Pt, respectively. From the sensitivity analysis for barley and rapeseed, scenario 1 (crop responses to fertilization level) showed the environmental burden was continuously increased with the amount of fertilization in barley cultivation, while it was not increased only at the optimum crop responses to fertilization in rapeseed (R3). With these results, rapeseed cultivation in winter fallow paddy contributed to the amounts of environmental burden much more than barley cultivation. It is, however, highly determined that environmental weighted point resulted from evaluating both cultivation was not significantly different.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.2
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• pp.60-68
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• 2008

Three land-use limitations including water hazard, soil erosion and fallow potential were evaluated to define an unfair area. Landscape indices in the unfair areas, defined by evaluations before and after landscape enhancement, were computed by Fragstats v3.3 and compared in order to propose a landscape enhancement plan. The results are as follows: First, as a result of the land evaluation, 388.56ha was analyzed for the 1st class(S1), 623.25ha for the 2nd class(S2), 138.08ha(S3s: 82.47ha, S3e: 51.88ha) for the 3rd class(S3), 230.44ha(N1w: 194.91ha, N1e: 23.09ha, N1es: 13.94ha) for the 4th class(N1), and 67.91ha(N2w: 60. 89ha, N2es: 7.02ha) for the 5th class(N2). The classes under the 3rd class(including the 3rd class) were determined as an unfair area, and proposed landscape enhancement for them. Second, it was proposed that unfair areas with potential water hazards(N1 w, N2w) be restored as a wetland and buffer zone. At this point, the farmers owning these fields could be compensated using the direct payment for landscape conservation(DPLC). Areas witha relatively lower slope(S3e) or a steep slope(N1e) containing soil erodibility potential were proposed to be restored as a sod-culture-applied field and substitute vegetation or potentially natural vegetation, respectively. The unfair areas having fallow potential(S3s, N1es, N2es) were proposed to apply special use crops for the S3s fields, native plants for the N1es fields, and intended fallow for the N2es fields. Third, after landscape enhancement, theforest had higher values in the indices of NP, PLAND, LSI, IJI, and TCA, while paddy and upland had lower values in most indices except NP and LSI. The forest patches increased and were more plentiful with their restoration and had much greater possibility to join with nearby patches. With continued restoration, forest patches will have a large core area and small number of patches due to the conglomeration of patches, which positively influences the species of diversity in the forest patches.

• Korean Journal of Environmental Agriculture
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• v.32 no.3
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• pp.185-192
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• 2013

BACKGROUND: As a result of rural exodus, aging of rural population, development of high-yield rice varieties and so on, abandoned paddy fields of South Korea have generally increased. The phytosociological studies are needed to recommend the effective vegetation management methods of abandoned paddy fields. The current study performed an analysis of vegetation characteristics by classifying plant communities for abandoned paddy fields in South Korea. METHODS AND RESULTS: A comparative analysis of syntaxonomy, synecology, and syndynamics was performed by using the Z.-M. method of phytosociology and vegetation survey which was obtained from an enumeration district of total 203 phytosociological releves of 5 regions in Gangwon-do, 5 regions in Gyeonggi-do, 2 regions in Chungcheong-do, 18 regions in Gyeongsang-do, and 10 regions in Jeolla-do. Alopecurus aequalis community, Juncus effusus var. decipiens community and Salix koreensis community were, respectively, identified as successional plant communities of the early stage, the middle stage, and the late stage in the vegetation of abandoned paddy field. Sere of abandoned paddy field can be classified, developmentally, into annual plant stage, perennial plant stage, shrub plant stage, and forest tree stage. Several kinds of dominant species rather than a distinct species were found in the middle stage of abandoned paddy field. CONCLUSION(S): In this study, changing pattern in vegetational communities of abandoned paddy field were understood. These results will provide important information for restoring and conserving the ecology of fallow ground.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.2
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• pp.173-181
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• 2015

Fluxes of carbon dioxide ($CO_2$) were measured above crop canopy using the Eddy Covariance (EC) method, and emission rate of methane ($CH_4$) was measured using Automatic Open/Close Chamber (AOCC) method during the 2012-2013 barley and rice growing season in a barley-rice double cropping field of Gimje, Korea. The net ecosystem exchange (NEE) of $CO_2$ in the paddy field was analyzed to be affected by crop growth (biomass, LAI, etc.) and environment (air temperature, solar radiation, etc.) factors. On the other hand, the emission rate of $CH_4$ was estimated to be affected by water management (soil condition). NEE of $CO_2$ in barley, rice and fallow period was -100.2, -374.1 and $+41.2g\;C\;m^{-2}$, respectively, and $CH_4$ emission in barley and rice period was 0.2 and $17.3g\;C\;m^{-2}$, respectively. When considering only $CO_2$, the barley-rice double cropping ecosystem was estimated as a carbon sink ($-433.0g\;C\;m^{-2}$). However, after considering the harvested crop biomass ($+600.3g\;C\;m^{-2}$) and $CH_4$ emission ($+17.5g\;C\;m^{-2}$), it turned into a carbon source ($+184.7g\;C\;m^{-2}$).

• Journal of Korean Society of Forest Science
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• v.90 no.3
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• pp.242-248
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• 2001

Changes in land-use can affect soil organic matter content and fertility. We compared total soil carbon and nitrogen concentrations, soil respiration, and nitrogen availability under three land-use types in central Korea; conversion of old rice field to natural willow-maple (Salix-Acer) forest, conversion of old field to artificial Korean pine (Pines koraiensis) forest, and indigenous oak (Quercus spp.) forest. After 20 years of fallow the area of rice field conversion to forest had higher soil carbon and nitrogen concentrations in the soil depth of 0-10cm and 10-20cm than the areas of field conversion to Korean pine forest and indigenous forest. In general, soil carbon and nitrogen concentrations decreased with soil depth. Organic matter accumulation as a balance of input and decomposition seemed to be higher in the soil of previous rice field, and carbon and nitrogen accumulation was largely confined to the topsoil. Soil respiration rates were greatest at the area of rice field conversion to forest, and appeared to be related to soil carbon and soil moisture. Soil nitrogen availability measured by the ion exchange resin bag method differed significantly among land-use types; soil inorganic nitrogen ($NH_4{^+}+NO_3{^-}$) and ammonium availability were highest in the soil under indigenous oak forest followed by conversion of old field to artificial Korean pine forest and conversion of old field to natural willow-maple forest.