• 한국유기농업학회지
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• 제19권spc호
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• pp.242-246
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• 2011

Organic kiwifruit orchard soils were compared with conventional ones in Korea. Soil structure of organic soil had higher gaseous and liquous phase as well as soil porosity in the surface soil. Although the nutritional level of each orchards were quite different among soils, the analysis of both system revealed that organic kiwifruit orchard soil had similar or even higher nutrient level (N and organic matter content in surface soil) compared to conventional ones. The organic matter content of deep soil also had the high tendency in deep soil of organic soil. Higher level of nitrogen in organic surface soil is presumably due to the excessive application of organic compost and liquid fertilizer rather than the contribution by grasses such as green manure. Available phosphorous level of organic system was quite high but similar in surface soil of both system, compared to the recommended level. Potassium, calcium and magnesium levels were also enough in organic kiwifruit orchard soils.

• 한국토양비료학회지
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• 제45권4호
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• pp.614-621
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• 2012

Although there is a broad dispute over genetically modified foods on safety, the worldwide adoption of transgenic crops is rapidly increasing. The objectives of this study were to identify trends in the effects of transgenic on crop yields and examine the effect of agricultural variables including crop type, biotech trait, tillage system, and yield environment on corn and soybean yield. A meta-analysis from the 34 peer-reviewed scientific literatures was conducted to compare the crop yield between transgenic crops and conventional varieties. Results showed that the yield of transgenic corn and soybean was strongly dependent on growing conditions. Transgenic hybrids had higher yield potential in the low crop yield environments such as high weeds and/or insect infestation, low soil water, and cool temperature conditions, while transgenic crops did not have yield advantages in high yield environments. The results from this study suggest that producers should consider the potential yield environmental conditions and possible yield reductions when producers choose crop hybrids in their fields.

• 한국토양비료학회지
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• 제40권4호
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• pp.326-329
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• 2007

Quantifying soil organic carbon (SOC) has long been considered to improve our understanding of soil productivity, soil carbon dynamics, and soil quality. And also SOC could contribute as a major soil management factor for prescribing fertilizers and controlling of soil erosion and runoff. Reducing tillage intensity has been recommended to sequester SOC into soil. On the other hand, determination of traditional SOC could barely identify the tillage practices effect. Physical soil fractionation has been reported to improve interpretation of soil tillage practices impact on SOC dynamics. However, most of these researches were focused onupland soils and few researches were conducted on paddy soils. Therefore, the objective of this research was to evaluate paddy soil tillage impact on SOC by physical soil fractionation. Soils were sampled in conventional-tillage (CT), partial-tillage (PT), no-tillage (NT), and shallow-tillage (ST)plots at the National Institute of Crop Science research farm. Samples were obtained at the three sampling depth with 7.5-cm increment from the surface and were sieved with 0.25- and 0.053-mm screen. Soil organic carbon was determined by wet combustion method. Significant difference of SOC contentwas found among sampling soil depth and soil particle size. SOC content tended to increase at the ST plot with increasing size of soil particle fraction. We conclude that quantifying soil organic carbon by physical soil particle fractionation could improve understanding of SOC dynamics by soil tillage practices.

• 한국토양비료학회지
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• 제6권2호
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• pp.83-88
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• 1973

염기치환용량 측정을 위하여 염기의 포화 과잉염기의 세척을 위한 작업단계에서 현재 사용되어 오던 원심분리기, 흡인여과장치 보다 새로이 고안된 Column set를 이용 하였을때 다음과 같은 양호한 결과를 얻었다. 1. CEC 측정치는 흡인여과시의 치와 99.91%인 고도의 상관이 있었으며 반복성의 변이가 흡인여과 1.94%에 비해 1/3이나 적은 0.66%로 정확도도 더욱 높았다. 2. Column set 이용시 흡인여과에 비하여 작업시간 및 노력이 1/3정도 절약되고 한거번에 다량의 시료를 처리할 수 있다. 3. 고가의 기계(Vacuum pump, Shaker, Section, Apparatus, Centrifuge) 등이 구비되지 않아도 CEC를 측정할 수 있었다.

• 한국토양비료학회지
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• 제50권6호
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• pp.615-622
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• 2017

This study was conducted to evaluate the odor reduction efficacy of the dip injection wet scrubber (DIWS) using tap water as washing fluid. The $NH_3$ and $H_2S$ removal efficiency of 7 day batch operated DIWS was evaluated twice over a total of 14 days of experiment. The $NH_3$ removal efficiency ranged from 26 to 37%. The $H_2S$ removal efficiency was between 22 and 30%. The pH of the washing fluid maintained below 8 and the $NH_4{^+}$ concentration tended to keep constant around 350 ppm after 5 days of washing-fluid replacement. Therefore, the 5-day washing fluid replacement interval is more preferable than the 7-day interval. The $NH_4{^+}$ concentration and the electrical conductivity (EC) showed a high correlation. The EC measurement can be used as an alternative to conventional $NH_4{^+}$ concentration measurement method for real time monitoring of washing fluid condition.

• 한국축산시설환경학회지
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• 제10권3호
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• pp.175-182
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• 2004

A study was conducted to develop a management policy of animal waste in Northern Chungbuk province through investigating the status of animal waste management. In management of swine manure, rotary composting including a simple piling method has a portion of $64\%$ using as a liquefied fertilizer $18\%$, purification $9\%$ and ocean dumping $9\%$ respectively. Most of them use the animal waste as a fertilizer to the agricultural land. The exercise ground of dairy farms was bedded with $70\%$ of sawdust and $30\%$ of conventional soil ground besides the stall. They had a storage tank for the waste water from milking parlor. Korean beef cattle farms mostly run sawdust stall, which changed new one in a term of 6$\~$12 months. In case of layer, manure management was conducted in the order of simple piling method, rotary composting and ventilation into the piling mostly. Comparing the amount of excreted animal manure with that of possible spreading, the latter can be spread more than 2.9 times than the former in Northern Chungbuk province. The Northern Chungbuk province is an appropriate place to carry out an environmentally friendly animal production. An utilization model as a liquefied fertilizer should be developed for paddy field, upland field, orchard, and forage field to in-crease the value of animal waste effectively.

• 한국작물학회지
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• 제41권1호
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• pp.109-114
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• 1996

논토양에서 경운방법과 시비수준을 달리하여 화성벼를 5년간 동일포장에서 재배했을 때 벼수량과 토양특성 변화를 조사분석한 결과는 다음과 같다. 1. 기종별 경운효율은 경운기 로타리구가 74.8％로서 제일 높고 트랙타 경운구가 59.0％로서 가장 낮았다. 2. 벼 이앙후 무경운구의 감수심이 가장 많았으며 벼 생육중기보다는 생육초기에서 많았다. 3. 벼 수량은 무경운 관행시비에 비해 경운기 로타리 농토배양시비구가 가장 많은 17％가 증수되었고 경운처리를 하므로서 벼수량은 6∼17％ 증수되었다. 연차간에는 2연차에서 수량이 가장 많았고 4년차에서 가장 낮았다. 4. 경운하지 않은 무경운구의 용적밀도와 고상률이 가장 높았으며 토양의 화학성 변화는 처리간에 일정한 경향이 없었다.

• 한국토양비료학회지
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• 제50권1호
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• pp.40-48
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• 2017

In this study, we evaluated the nitrogen (N) mineralization potential and Nitrogen use efficiency (NUE) of oil-cake, compost, hairy vetch and barley, which are the most widely used organic amendments in South Korea. The N mineralization potential (No) for organic fertilizers treated soil was highest for the hairy vetch treatment with a value of $18.9mg\;N\;100\;g^{-1}$, followed by oil-cake, barley and compost. The amount of pure N mineralization potentials in hairy vetch, oil-cake, barley and compost treatments were 8.42, 7.62, 3.82 and $3.60mg\;N\;100\;g^{-1}$, respectively. The half-life ($t_{1/2}$) of organic N in soil amended with oil-cake fertilizer mineralized quickly in 17 days. While, $t_{1/2}$ values of organic N for the compost and barley treatments accounted to 44.4 and 44.1 days, respectively. Oil-cake was good in supplying nutrients to plants. Compost and barley inhibited plant growth in the beginning growth stage and this is attributed to N immobilization effect. The results of this study highlight that compost and barley could be used as potential slow release fertilizers in conventional agriculture.

• 한국작물학회지
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• 제21권1호
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• pp.9-14
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• 1976

1972년 우리나라에서 맨 처음 육성된 과맥품종으로 내한성이 强하고 다수성인 '광성'과 1974년에 육성된 단간 조숙 다수성인 방사006 두 품종을 가지고 드릴파재배에 따른 방시수준의 효과에 관한 시험결과를 요약하면 다음과 같다. 1. 관행파보다 드릴파가 종실수량이 8%나 많았고 증수요인의 하나인 수수가 현저하게 많았다. 2. 광성보다 방사006가 내도복성이 강하였다. 3. 관행파나 드릴파에서 광성보다 방사006가 시비량 증가에 따른 적응성이 높았다. 4. 품종별로 비교하던 방사006가 광성보다 종실중이 5% 높았다. 5. 시비수준별로 종실중을 비교하면 표준비에 비하여 100% 증비에서는 19% 증수되었다. 6. 드릴파 표준비에서는 광성에 비하여 방사006의 수량이 감소되었으나 증비에서는 크게 증수를 보인 내비성 품종이었다. 7. 광성보다는 방사006가 드릴파종재배에 적합한 품종으로 사료된다.

• Journal of Applied Biological Chemistry
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• 제65권1호
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• pp.1-6
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• 2022

요소는 가장 보편적인 질소비료 중 하나인데 빠른 가수분해와 환경으로의 질소 손실로 인해 작물에 질소 이용효율이 낮다. 따라서 요소 비료에서 질소 방출을 제어하는 것이 중요하다. 본 연구에서는 토양의 요소가수분해효소를 억제하여 요소에서 과도한 질소 용출을 방지하기 위해 목초액을 처리하였다. 목초액의 유효성분은 목초액을 처리하지 않은 토양에 비해 암모늄태 질소의 추출량을 79.7% 감소시켜 토양에서 요소의 암모니아화를 억제한 것으로 나타났다. 목초액이 요소의 시비 효율에 미치는 영향을 평가하기 위해 요소와 목초액을 처리한 토양에서 배추(Brassica campestris var. Pekinensis)를 각각 포트와 포장에서 재배하였다. 목초액을 요소와 같이 처리했을 때 관행적으로 사용하는 요소량의 반을 사용하였으며 관행과 비교하여 유사한 배추 생체중을 보였다. 배추의 질소 함량은 목초액 처리구에서 낮아 배추가 질소를 효율적으로 사용한 것으로 판단된다. 따라서 요소를 목초액의 유효성분과 같이 처리하면 시비량과 시비 횟수를 감소시킬 수 있다.