• 미생물학회지
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• 제49권2호
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• pp.131-136
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• 2013

본 연구에서는 헤어리베치로부터 뿌리혹 형성능과 질소 고정능이 우수한 Rhizobium 균주를 분리하고자 하였다. 전국의 일곱 군데 헤어리베치 재배 지역에서 수집 후 뿌리혹으로부터 균주를 분리하였고, 헤어리베치에 분리 균주를 재접종하여 뿌리혹 형성능과 질소 고정능을 확인하였다. 그 결과, 52개의 Rhizobium 속 균주를 분리하였고, 이 중 0.5% NaCl 농도 이상에서 자라는 Rhizobium은 16균주이었다. 뿌리혹 형성능은 16개 균주 중 Rhizobium sp. RH1, RH3, RH81, RH82, RH84, RH93의 균주를 접종한 시험구에서 우수하였다. 또한, 질소 고정능을 확인한 결과 Rhizobium sp. RH84가 가장 높은 acetylene reduction activity를 보였다. 이러한 결과는 향후 염의 분포가 불균일한 간척지에 적용 시에도 헤어리베치의 생육을 촉진해 녹비 작물로의 활용 가능성을 높여주는 결과로 판단된다.

• 농업과학연구
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• 제24권1호
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• pp.94-107
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• 1997

Producing organic farm products is one of the high-payoff farming practices considering the rapid increase of consumer's purchasing power. The purpose of this study is to identify the optimal organic farming system in relation to farm income. To cope with the above objectives, present farming conditions and profitability of 15 farmers producing organic products including rice and leaf vegetables as lettuse and cabbage were surveyed in Hongsung and Ahsan Gun, Chungnam Province. Based on the surveyed data, maximization of organic farm income were analyzed under the constrained conditions such as limited monthly labour inputs and competitive use of land by Linear Programming Model. The results of this study can be summarized as follows. 1. In the profitability analysis of 15 farmers producing organic products, rice farmers could earn their farm income more than that of conventional farmers by 50%. On the other hand, the controlled lettuce farmers could get more about 100% than that of it. But the controlled cabbage farm could get more about 40% of it. These organic farm products were saled at high prices comparing with the prices of conventional farm products by 170% ~ 230% even though the crop yields produced by organic materials had decreased. 2. According to the labor requirement of the organically produced crops, rice cultivation was needed more labour inputs than the conventional farming method by 130%. On the other hand lettuce and cabbage could saved labour requirement by 40% and 80% of those respectively. Especially for the rice cultivation concern, higher labor requirement was due to the activities as organic fertilization, soil preparation and pest and weed controll, etc. 3. With the surveyed data from farmers who produced farm commodities, L.P. analysis was implemented to find out the optimul farming system and the maximum income. According to the results of L.P. analysis, 58% of total farm income could get more than the conventional farming system In the case of rice cultivation, one ha of paddy was recommendable to save more labour inputs than the controlled leaf vegetables such as lettuse and cabbage. However, in the controlled leaf vegatables, only 73% of total upland equivalent to 0.3 ha should be cultivated under the condition of labor shortage as the restricted 4 workers. And increasing the size of hogs raising should be recommened to achieve self-sufficiency of organic fertilizer. As pointed out the possibility of organic farming, present farmers producing organic farm products could be able to maximize their income by expanding organic farm size with regard to all conditions of our organic industry. Of course, there are many difficulties in the course of developing organic agriculture. So Government should effort to support the development of our organic agriculture considering the various aspects of production, marketing, Quality certification of organic produces.

• 한국토양비료학회지
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• 제17권1호
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• pp.1-6
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• 1984

화산회토(火山灰土)인 제주도(濟州道) 토양(土壤)에 있어서 지대별(地帶別) 토지이용(土地利用)에 화학적(化學的) 특성변화(特性變化)를 고찰(考察)하였다. 1960년대(年代) 초(初)부터 농경지(農耕地)가 중산간지방(中山間地方)으로 급격(急激)하게 증대(增大)되어 가고 있으나 대부분은 농경지(農耕地)가 해안지방(海岸地方)에 분포(分布)되어 있기 때문에 경작지(耕作地)가 오래된 해안지방(海岸地方) 토양(土壤)일수록 pH, 염기포화도유효인산(有效燐酸), 치환성(置換性) Ca, Mg 및 K함량(含量)이 높으며, 유기물함량(有機物含量) 및 양(陽)이온치환용량(置換容量)은 낮아지는 경향(傾向)이었다. 전국평균(全國平均) 비교(比較)하여 유기물함량(有機物含量) 및 양(陽)이온치환용량(置換容量)이 매우 높으며 치환량(置換量) Ca, Mg, K 등(等)도 높은데 반(反)하여 유효인산(有效燐酸) 염기포화도는 극(極)히 낮았다. 총염기중 1가(價) 양(陽)이온이 차지하는 비율(比率)이 비교적(比較的) 높은데, 이는 해안지방(海岸地方)에서 산간지방(山間地方)으로 올라갈수록 높아지는 경향(傾向)이었다. 따라서 해안지방(海岸地方)의 토양(土壤) pH가 높은 것은 해풍(海風)의 영향에 의(依)한 것이라 보다, 오랜 경작(耕作)과 더불어 석회시용(石灰施用)이나 용성인시(熔成燐施)와 같은 염기성시료의 다량(多量) 시용(施用)에 의(依)한 것임을 알 수 있다.

• 원예과학기술지
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• 제34권4호
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• pp.587-595
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• 2016

본 연구는 염류-나트륨성 토양 조건에서 작물의 생육에 미치는 퇴비, 석고, 인산의 효과를 평가하기 위해, 2013년과 2014년에 배추를 포트재배하였고, 퇴비와 화학비료를 시비한 표준시비 처리구(S), 표준시비에 퇴비 추가 처리구(S + C), 석고 추가 처리구(S + G), 인산 추가 처리구(S + P), 석고-인산 추가 처리구(S + GP) 등 다섯 처리를 두어 비교하였다. 배추 건물중은 2013년과 비교하여 2014년에 크게 증가하였다. 토양의 전기전도도(EC)가 2013년에 비해 2014년에 감소하지 않았지만, 토양용액내 양이온 중 나트륨의 평균 비율($SAR_{1:5}$)이 2013년 $17.3{\pm}1.1$에서 2014년 $11.2{\pm}2.7$로 크게 감소하였다. 토양개량제 중에서 석고를 시용하였을 때 배추의 생육이 가장 좋았다. 표준시비 처리구와 비교하여 석고 추가 처리구에서 배추 건물중이 2013년에 7.0g/plant(48.2%) 더 높았고 2014년에 7.9g/plant(16.6%) 더 높았다. 석고 시용 시 오히려 토양 전기전도도가 증가하여 배추 생육에 부정적이었지만, SAR이 2013년과 2014년에 각각 14%, 38% 감소하여 배추생육에 긍정적인 효과가 있었다. 본 연구 결과는 염류-나트륨성 토양이 분포하는 간척지에 석고를 시용하여 토양의 나트륨 비율을 개선함으로써 작물의 생육을 촉진시킬 수 있다는 것을 시사해 주었다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제11권1호
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• pp.65-76
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• 2006

본 논문은 지하수함양의 공간분포를 분석할 수 있는 격자기반의 토양물수지방법을 제시하고, 제주도의 외도천유역에 적용하였다. 유역을 격자로 분할하고, 각 격자의 5년 동안의 물수지를 일단위로 계산하였으며, 격자의 일별 강수량은 10개 지점의 강수량자료로 보간법에 의해 산정하였다. SCS유출곡선지수, 토양수분보유능, 작물계수 등 매개변수의 분포는 토양과 토지이용특성에 대한 GIS분석으로 부터 구하였다. 유출곡선지수는 하천유출량 관측자료로 보정하였다. 사례유역에 대한 분석결과 강수량은 표고가 증가함에 따라 1,665 mm/년부터 3,382 mm/년까지 증가하며 지하수함양량은 강수량이 증가함에 따라 372 mm/년부터 2,576 mm/년까지 증가한다. 강수량이 상대적으로 적은 지역에서 유출율과 증발산율이 다른 지역보다 더 크기 때문에 지하수함양이 강수, 직접유출, 증발산, 지하수함양과 같은 물수지 성분 중에서 공간적인 변이가 가장 큰 것으로 나타나고 있다.

• Journal of Animal Science and Technology
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• 제60권2호
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• pp.1.1-1.6
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• 2018

Background: Maize fodder is being used as staple feed for livestock but it lacks protein and essential amino acids; lysine and tryptophan. Intercropping maize with leguminous soybean crop is promising technique under limited land resources of South Korea but it can only give considerable advantages when adequate distance is provided between corn and soybean rows. Main aim of present study was to find-out adequate distance between corn and soybean seeding rows for optimum growth, yield and nutritive value of intercropped forage. Methods: Different interrow distances between corn and soybean were evaluated under four treatments, viz. 1) Corn sole as positive control treatment 2) Zero cm between corn and soybean (control); 2) Five cm between corn and soybean; 3) 10 cm between corn and soybean, with three replicates under randomized block design. Results: Findings depicted that height and number of corn stalks and ears were similar (P > 0.05) among different treatments. Numerically average corn ear height was decreased at zero cm distance. Dry matter percentage in all components; corn stalk, corn ear and soybean was also found not different (P > 0.05) but dry matter yield in component of corn ear was lower (P < 0.05) at zero cm distance as compared to that of 5 and 10 cm interrow distances. In case of nutritive value, total digestible nutrient yield in intercropped corn was also found lower (P < 0.05) at zero cm distance than that of 5 and 10 cm interrow distances between corn and soybean seeding rows. Substantial decrease in dry matter yield of maize ear at zero cm distance might be attributed to factor of closed interrow spacing which made interplant competition more intensified for light interception, necessary for photosynthetic activity. Lower dry matter yield in ear also reduced total digestible nutrients in intercropped maize because it was determining factor in calculation of digestible nutrients. The optimum yield and nutritive value of forage at wider interrow distance i.e. 5 cm between corn and soybean might be due to adequate interseed distance. Conclusion: Conclusively, pattern of corn and soybean seeding in rows at 5 cm distance was found suitable which provided adequate interrow distance to maintain enough mutual cooperation and decreased competition between both species for optimum production performance and nutritive value of intercropped forage.

• 한국초지조사료학회지
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• 제25권2호
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• pp.113-118
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• 2005

본 시험은 충청남도 당진군에 소재한 대호 간척지내 시험포장에서 전작물로 벼 재배된 곳을 밭으로 전환하여 공시 초종으로 총체보리 2품종(올보리, 알보리), 호밀 2품종(올호밀, Koolgrazer) 그리고 이탈리안 라이그라스 2품종(화산 101호, Florida80)을 총체보리와 호밀은 10월 10일경, 이탈리안 라이그라스는 9월 30일경에 조파하여 각 작목 간에 따른 토양염류도 변화, 수량 및 사료가치를 비교 검토코자 2002년에서 2004년까지 2년간 수행되었다. 각 작물재배구의 계절별 토양염류도는 각 작물구 모두 파종 당시에 높았으며 월동 후 수확시까지 점진적으로 낮아졌다. 건물수량은 이탈리안 라이그라스가 가장 높았으며 총체보리 그리고 호밀 순으로 나타났다. 조단백질함량은 이탈리안 라이그라스가 가장 높았으며, 총체보리 그리고 호밀 순으로 나타났으며, 조섬유 함량은 호밀이 가장 높았으며, 이탈리안 라이그라스 그리고 총체보리 순으로 높았다. ADF 함량은 총체보리>이탈리안 라이그라스>호밀 순으로 낮았으며, 식물체 중나트륨(Na) 함량은 총체보리 >이탈리안 라이그라스 >호밀 순으로 높았다. 위의 결과로 볼 때 간척지에서 겨울 사료작물로 재배할 때 이탈리안 라이그라스가 가장 우수하였고 다음으로 총체보리가 가능하였다.

• 한국산학기술학회논문지
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• 제21권8호
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• pp.579-592
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• 2020

여자만 북서해역 꼬막 어장의 수괴(수형), 영양염 등 수질환경과 식물플랑크톤 군집의 변동 특성을 파악하기 위해 2017년 봄(5월), 여름(8월) 및 가을(11월) 7개 정점을 조사하였다. 분석 결과, 꼬막어장의 수형은 수온과 염분 변화에 따른 계절특성이 명확하였다. 영양염 중 규산염은 연중 풍부였지만, 봄과 여름은 인산염이 결핍되었고, 가을은 질소원이 결핍되는 것으로 나타났다. 식물플랑크톤 군집에서 출현종은 매우 단순하였으며, 현존량도 매우 낮았다. 우점종은 연중 규조류에 우점 되어, 봄은 Skeletonema costatum-ls, Nitzschia longissima, 여름은 Pleurosigma normanii, Coscinodiscus gigas, 가을은 N. longissima, Pseudonitzschia pungens, Chaetoceros curvisetus, Eucampia zodiacus가 우점 출현하여, 여름에 편모조류 출현이 낮은 특성을 보였다. 상관분석과 주성분 분석의 결과 여자만 북서해역 꼬막어장의 생물 해양학 특성은 계절에 따라 수질 환경 및 식물플랑크톤 군집에 많은 차이가 있으나, 전체적으로는 육상에서 공급되는 무기 및 유기물질 및 낮은 수심으로 해수혼합에 따른 표층퇴적물의 재부유에 의한 영양염 공급, 그리고 해역자체의 생물생산과 무기화 과정의 균형에 의해 해양환경 특성 및 식물플랑크톤 생산이 결정되는 것으로 판단되었다.

• 산경연구논집
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• 제8권6호
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• pp.87-95
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• 2017

Purpose - The structural changes of Korean agriculture are complex due to heterogeneous production processes and farms' features. This study analyzed trends of dualism in Korean agriculture over the period 2000-15 based on farm-level data to clarify the specific trends of dualism in terms of farm income, farm-size, and farm operators' age. From the results of this study, we would be able to understand the features of structural changes in Korean agriculture more profoundly. Research design, data, and methodology - We incorporated farm-level data in South Korea: Agricultural census and Farm household economy survey. As measures of inequality, we used size-weighted quantiles, and normalized Gini coefficients as well as mean and conventional quantiles. The size-weighted quantiles are more robust to changes in the number of small farms, but they are more sensitive to changes in the distribution of farm-size. Thus, they would be more useful to identify trends of dualism of Korean agriculture. Results - The results show that the farmland distribution of crop farms became more skewed and dispersed. However, the herd distribution of livestock farms became more concentrated. To be specific, their mean and 1st quantile increases more rapidly than their size-weighted 2nd quantile and size-weighted 3rd quantile. Gini coefficients of livestock farms regarding their herd distribution decreased by 0.1 on average. In the case of income distribution, the results indicate that the polarization regarding farm household/agricultural/non-agricultural income became more severe. However, we also found that the distribution of transfer income became concentrated continuously. The results imply that transfer income including subsidies would decrease farm income polarization. Lastly, during the study periods, Korean farms were aging over time, and age distribution of them more concentrated. Conclusions - The structure of Korean agriculture has been changing, even though the absolute size of it decreased over time. Land (herd) distribution became more dispersed (concentrated). Inequality regarding agricultural income became more severe, and it made farm household income more polarized even though transfer income would decrease income gaps among farms. Lastly, farms continue to age regardless of farm types and this might affect the structural changes in Korean agriculture in the future.

• 한국토양비료학회지
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• 제49권2호
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• pp.115-124
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• 2016

The objectives of this study were to evaluate the soil fertility about plastic film house, upland, and orchard in Gyeongbuk Province, Korea. The surface chemical properties of soil samples were investigated every 4 year from 2000 year at upland, 2001 year at orchard, and 2002 year at plastic film house. During 12 year's monitoring, mean soil pH was increased by 0.7 and 0.8 pH unit from pH 5.7 in upland and orchard, respectively, 0.5 pH unit from pH 6.5 in plastic film house. About 50% of all the field samples occupied within the recommended pH range (pH 6-7). Although soil organic matter (SOM) was gradually increased by about $10g\;kg^{-1}$ for 12 years, 40% of orchard, 49% of plastic film house, and 77% of upland soil samples were still below the 3% SOM. The mean concentration of available phosphate for 12 years in upland, orchard, and plastic film house were 530, 600, and $760mg\;kg^{-1}$, respectively. The relative frequencies exceeding the recommended available phosphate range ($300-550mg\;kg^{-1}$) were 43%, 53%, and 66% at upland, orchard, and plastic film house soils, respectively. $NH_4OAc$ exchangeable $K^+$ of upland, orchard, and plastic film house in the last soil test were 0.8, 0.9, and $1.6cmol_c\;kg^{-1}$, respectively. The relative frequencies above the recommended K level were 56% and 70% of orchard and plastic film house soil samples, respectively. The levels of crop nutrients except exchangeable Ca and Mg in upland soil were tended to increase gradually in the three fields. Exchangeable Mg, EC, available phosphate, organic matter and soil pH could be used as principle components to differentiate the chemical properties of three land fields. This analysis revealed that the soil fertility was affected by cropping method and field management, although additional research is needed to assess the importance of management on soil chemical properties and many fields indicate an opportunity for improvement in fertilizer management.