• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.195-197
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• 2003

Soil moisture is a crucial variable in research works of hydrology, meteorology and plant sciences. Adequate soil moisture is essential for plant growth; excesses and deficits of soil moisture must be considered in agricultural practices. There are already several remote sensing methods used for monitoring soil moisture, such as thermal inertia, vegetation water-supplying index, crop water stress index and multi-factor regression. In this paper, an improved method has been discussed which is based on the thermal inertia. We analyzed the problems of monitoring soil moisture using satellites at first, and then put forward an simplified method which directly uses land surface temperature differences to measure soil moisture. Also we have taken the influence of vegetation into account, and import NDVI into the model. The method was used in the study of soil moisture in Heilongjiang Province, China, and we draw the conclusion by the experiments that the model can evidently increase the precision of monitoring soil moisture.

• 한국환경농학회지
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• 제28권1호
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• pp.15-19
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• 2009

대기중으로 휘산되는 대부분의 암모니아는 농경지에서 시용하는 가축분뇨 퇴비와 질소비료에서 유래한다. 본 연구는 밭 토양에서 돈분 퇴비 시용방법에 따른 암모니아 휘산량을 소형원드터널 방법을 이용해서 정량적으로 평가하였다. 돈분 퇴비(20 Mg/ha) 표층살포(SA), 표층살포 후 즉시 경운(IRA), 표층 살포 3일 후 경운(RA-3d) 처리의 13일 동안 암모니아 휘산량은 각각 28.7, 8.7, 24.3 kg N/ha로 IRA 처리구는 SA 처리구에 비해 70% 저감효과를 가져왔다. 그리고 SA 처리구의 퇴비 처리 후 24시간 이내 휘산된 암모니아 양은 총 휘산량의 61%로 대부분의 암모니아는 시용 초기 짧은 시간 내에 휘산됨을 알 수 있었다. 석회와 퇴비 혼용시용 후 교반(L+C mix), 퇴비표층 살포 3일후 석회시용 교반(C+L3D), 석회시용 3일 후 퇴비시용 교반(L+C3D) 처리구의 22일 동안 총 암모니아 휘산량은 각각 40.1, 31.4, 27.7 kg/ha이었다. 따라서 가축분 퇴비 시용시 석회를 혼용하는 것은 피해야 하며, 만일 동일 작기내 시용이 불가피할 경우는 퇴비시용에 앞서 석회를 먼저 충분한 일수를 앞두고 시용하는 것이 암모니아 휘산량을 저감시킬 수 있다는 결론을 얻었다.

• Journal of Biosystems Engineering
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• 제29권6호
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• pp.487-494
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• 2004

This study was conducted to develope a fertilizer-soil incorporation band tiller for the walking cultivator. Because the mixing of soil and fertilizer in the furrow of dry-field has been done manually, several time, heavy labor and much man power were required for the job. This rotary type implement is developed to substitute this manual operation for soil-fertilizer incorporation. The results of this study are summarized as follows : 1) This implement was composed of tilling device, fertilizer application device, frame and tail wheel device. 2) The revolution of driving wheel was $11\~28\;rpm$, that of application roller was $13\~14\;rpm$ the application rate range per revolution of driving wheel was $4.43\~11.80\;g$g and the application rate range by the working speed and the opening quantity was $84.12\~557.20\;g/min$. 3) The adequate working speed was $0.20\~0.40\;m/s$ and the required minimum width of open furrow was 250 mm.

• Journal of Applied Biological Chemistry
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• 제42권3호
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• pp.134-139
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• 1999

The distributions of Cd, Cu, and Zn concentration in soil treated with one (1988) or two (1988 and 1993) applications of sewage sludge at rates of 0, 25, 50, and $100Mg\;ha^{-1}$ (dry weight basis) were determined to assess the accumulation and mobility of the heavy metals. The heavy metals accumulated almost entirely in 0 to 15 cm soil depths. Small amounts of the metals moved out of the tillage zone (0-15 cm depth) into the subsoil, but even at the high rate of sewage sludge, little movement of heavy metals occurred below 100 cm depth. The water-extractable Cd, Cu, and Zn concentrations were very low regardless of the rate of sewage sludge application. Availability of metals as determined by DTPA extraction showed the percentage of DTPA-extractable/total concentration increased with sewage sludge application. In the 0-15 cm depth of sewage sludge treated soil, the percentage of DTPA-extractable/total concentration was higher than 46% for Cd, but the value was less than 27% and 17% for Cu and Zn, respectively. The Cd, Cu, and Zn added to this calcareous clay soil by sewage sludge application were not very mobile, and the amount of plant available form was very small.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 창립총회 및 춘계학술발표회
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• pp.24-27
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• 2000

The development of land classification and soil productivity rating systems (SPR) are examined for their application to valuation of agricultural land in South Dakota, USA. The application of SPR data to land valuation work conducted by real estate appraisers, tax assessors, and economists are discussed along with an assessment of its benefits and limitations.

• 한국토양비료학회지
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• 제30권4호
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• pp.328-333
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• 1997

질소를 함유한 유기인계 살충제로 널리 사용되고 있는 diazinon이 논토양에 살포되었을 때 토양내에서 일어나는 질소대사중 암모니아휘산에 미치는 영향을 조사하고자 질소질비료원의 종류와 diazinon 처리량에 따른 암모니아 휘산의 차이를 조사하였다. 1. 시험토양에 요소, 유안, 유기질비료를 처리후 담수상태가 지속되면서 토양 pH가 약간씩 증가하였으며 토양 pH 증가에 함께 암모니아 휘산량이 증가하는 경향이었다. 2. 질소비료원을 시비하지 않은 시험구에서 diazinon 처리량을 0, 35, 70, 105g a.i./10a로 하였을 때 처리량에 따른 암모니아 휘산량 차이는 인정되지 않았다. 요소, 유안 및 유기질비료원을 시비후 diazinon 처리시 70g a.i/10a에서 가장 많은 암모니아 휘산이 발생하였으나 시간이 경과함에 따라 완만하게 감소하는 경향이었다. 3. 요소비료, 유기질비료 및 유안비료 처리시 질소질비료원의 종류에 따라 암모니아 휘산량이 차이를 보였는데 요소비료는 diazinon 무처리시 약 23%, diazinon 표준처리시 약 42%, 2배처리시 약 66%, 유안비료는 diazinon 처리시 약 3.2%, diazinon 표준처리시 약 4.8%, 2배처리시 약 5.7%, 유기질비료는 diazinon 무처리시 약 1.8%, diazinon 표준처리시 약 8.9%, 2배처리시 약 28.4%의 암모니아 휘산이 발생하였으며 요소비료>유기질비료>유안비료의 순으로 나타났다.

• 농업과학연구
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• 제51권3호
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• pp.271-281
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• 2024

The application of biochar to soil for sustainable agriculture has been considered to have a positive impact on soil fertility and crop productivity. In this study, biochar derived from rice husk and chicken manure was applied to the soil at rates of 1% and 3% by weight, respectively, for lettuce cultivation experiments. The results indicated that both rice husk biochar and chicken manure biochar were effective in improving soil fertility through soil pH correction and increased nutrient content. The nitrogen content and pH of the biochar increased the available nitrogen and phosphate in the soil, creating a soil environment conducive to the growth enhancement of lettuce. In particular, after the application of 3% chicken manure biochar, the soil exhibited the highest levels of available nitrogen and phosphate at 87.42 mg·kg^-1 and 69.07 mg·kg^-1, respectively. Plant fresh weight increased with rising biochar amount, with the 3% chicken manure biochar treatment (228.25 g·plant^-1 fresh weight [FW]) exhibiting superior fresh weight compared to 3% rice husk biochar treatment (120.88 g·plant^-1 FW). The nutrient content in lettuce, except for K₂O, was higher in the chicken manure biochar treatment compared to the same dosage of rice husk biochar. Therefore, for enhancing lettuce productivity and soil fertility, chicken manure biochar appears to be more effective than rice husk biochar, and increasing the application rate up to 3% showed improvement effects without adverse impacts. However, excessive application of chicken manure biochar may lead to an increase in soil pH and electrical conductivity (EC) beyond the optimal range, requiring further assessment of application rates.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.136-139
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• 2003

The combined effect of bioaugmentation of dechlorinating bacterial cultures and addition of iron powder (Fe$^{0}$ ) on reductive dechlorination of tetrachloroethylene (PCE) and other chlorinated ethylenes in a artificially contaminated soil slurry (60$\mu$mo1es PCE/kg soil) were tested. Two different anaerobic bacterial cultures, a pure bacterial culture of Desulfitobacterium sp. strain Y-51 capable of dechlorinating PCE to cis-1, 2-dechloroethylene (cis-DCE) and the other enrichment culture PE-1 capable of dechlorinating PCE completely to ethylene, were used for the bioaugmentation test. Both treatments introduced with the strain Y-51 and PE-1 culture (3mg dry cell weight/kg soil) showed conversion of PCE to cis-DCE within 40 days. The treatments added with Fe$^{0}$ (0.1 -1.0 %(w/w)) alone to the soil slurry resulted in extended PCE dechlorination to ethylene and ethane and the, dechlorination rate depended on the amount of Fe$^{0}$ added. The combined use of the bacterial cultures with Fe$^{0}$ (0.1-1.0%) showed the higher PCE dechlorination rate than the separated application and the pattern of PCE dechlorination and end-product formation was different from those of the separated application. These results suggested that the combined application of Fe$^{0}$ and the bactrial culture, specially the complete dechlorinating enrichment culture such as PE-1 culture, would be practically effective for remediation of PCE contaminated soil.

• 한국유기농업학회지
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• 제19권spc호
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• pp.218-221
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• 2011

To improve the soil properties of physical and microbial community rice bran and wood charcoal were applied in the continuously cultivated plastic film house soil. Soil physical properties were improved by application of rice bran and charcoal compared to chemical fertilizer application (control) by 8~14% in bulk density and 5~9% in soil porosity. Changes in the biological ratio indexes of fatty acids in the soils were detected depending on the inputted materials. Especially in application of rice bran including mixture with charcoal, much more fungi and less bacteria were detected and the ratio of fungi to bacteria was increased, suggesting the more organic carbon metabolically active in these treatments. The high ratio of aerobe to anaerobe suggested the better aerobic conditions were in the soil inputted wood charcoal. From these results, it is important and possible to select some materials for the organic pepper cultivation, which may improve the poor condition soil.

• 한국작물학회지
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• 제49권3호
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• pp.194-198
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• 2004

본 연구는 남서해안 간척지에서 토양 염농도(저염; 0.1%, 중염; 0.3∼0.4%)별로 쌀 품질 향상을 위한 적정 질소 시비량을 구명하기 위하여 시험한 결과를 요약하면 다음과 같다. 1.유추분화기의 초장은 질소 시비량이 많을수록 컸고, 토양염농도간에는 저염 토양에서 켰다. 2. 출수기는 저염 토양에서는 표준비인 N20kg/10a에 비해 N8-N16kg/10a까지는 같았으나 N24kg/10a에서는 1일 늦었고, 중염 토양에서는 N8-N16kg/10a 까지는 1일이 삘랐고 N24kg/10a에서는 같았으며, 토양 염농도간에는 저염 토양에서보다 중염 토양에서 4일 정도 늦었다. 3. 질소시비량이 많을수록 간장이 크고, 포장도복이 심했다. 4. 저염 토양에서 질소시비량이 많을수록 $\textrm{m}^2$ 당 립수는 많았으나 등숙비율이 낮아져 발 수량은 N12kg/10a이상에서는 유의차가 없었으며, N12kg/10a이하에서 현미의 완전미율이 높고 단백질 함량이 낮았다. 5.중염 토양에서는 질소시비량이 많을수록 $\textrm{m}^2$ 당 립수가 많고 등숙비율이 비슷하여 발 수량은 질소시비량이 많을수록 높았으나 N20kg/10a 이상에서는 유의차가 없었고, 현미의 완전미율과 단백질함량은 질소시비량간에 비슷하였다. 따라서 남서해안 간척지에서 쌀 수량 및 미질 등을 고려해 볼 때, 저염 토양에서는 N12kg/10a, 중염 토양에서는 N20kg/10a이 적당할 것으로 생각된다