• Proceedings of the KSEEG Conference
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• 2002.04a
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• pp.86-88
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• 2002

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1997.05a
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• pp.4-7
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• 1997

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.02a
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• pp.61-73
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• 2001

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.1024-1034
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• 2010

In order to select the demonstration farm site for agricultural investment by Korean fund, 14 sites were investigated by soil morphological characteristics and were evaluated by rating method in the Oudomxai province of Laos. Land evaluation was carried out by using eight factors, such as site accessibility, soil erosion susceptibility, easiness of farm mechanization, irrigation water obtainability, suitability of soil physical and chemical properties for crop growth, cost for establishment of farm foundation and land obtainability. In addition, one site to have been highly ranked was soil physico-chemically studied for farm planning. The site of heavy clayey soil has hydraulic conductivity of 26.27~40.64 cm $day^{-1}$, organic content of lower than 14 g $kg^{-1}$, available phosphate content of lower than 3 mg $kg^{-1}$, exchangeable cations of lower than 0.38, 11 and 3.1 cmolc $kg^{-1}$ in K, Ca and Mg, respectively. Major important limitations for establishment of demonstration farm were concluded as heavy soil-texture, high soil erodibility, low organic matter and phosphate contents, and insufficient irrigation water in the Oudomxai province of Laos.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.310-313
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• 2000

본 연구에서는 현재 사용 종료된 매립지 재사용을 위해 정비를 실시 중인 전국 매립지 중에서 충남 공주시 금홍동에 위치한 사용 종료된 매립지를 대상으로 하여 사업 지구 및 그 주변지역의 환경질 평가를 위하여 토양에 관한 오염도 조사를 실시하였다. 시료는 매립지 내 1개 지점과 주변 논 2개 지점, 밭 1지점으로 총 4개 지점에서 채취하였다. 토양시료의 분석항목은 토양환경보전법에서 제시하는 총 11개 항목으로 하였으며, 실험방법은 토양오염공정시힘방법에 준하여 실시하였다. 실험결과 토양환경보전법상 농경지에 대한 우려기준과 비교하여 전 항목이 기준에 크게 미치지 못하는 것으로 나타났다. 토양질의 면에서 된다면 이 매립지 부지는 일반적인 용도의 토지로써 사용이 가능하다고 사료된다.

• Proceedings of the Mineralogical Society of Korea Conference
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• 1996.10a
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• pp.36-52
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• 1996

유황비료의 효과는 한국에서 널리 인정퇴고 있다. 유황은 토양 산도를 낮게 하고 과실의 당도를 증가 시켜 품질을 향상시킨다. 유황비료는 논과 밭토양에서 산도를 약간 변화시키며 특히 유황분말은 토양산도 교정에 유용하다. 한국농업은 질 높은 농산물을 점차 요구함에 따라 유황비료의 시용이 필요하게 될 것이다. 앞으로 유황비료에 대한 연구는 특별한 토양조건과 작물에서 적정 유황 수준을 밝혀내는 것이다.

• Proceedings of the Korean Society of Crop Science Conference
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• 2023.04a
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• pp.145-145
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• 2023

• Proceedings of the Korean Society of Crop Science Conference
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• 2023.04a
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• pp.115-115
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• 2023

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.2
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• pp.195-202
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• 1983

Sixty paddy soil samples were collected from the different Korean agricultural climatic area to find relationship between soil physicochemical properties and soil microorganisms. The results are summarized as follows : 1. The mean numbers of microorganisms in collected paddy soils were $121.8{\times}10^5$ in bacteria (B), $22.5{\times}10^5$ in actinomycetes (A) and $32.4{\times}10^3$ in fungi (F) per gr soil. The ratios of B/F, B/A, and A/F were 385, 5.1 and 82, respectively. 2. Number of soil microorganism was lowest in Mountainous area, lower in Eastern Coast, Gyeonggi Bay and Chungcheong Continental area, but higher in Honam Plain and Southern Part. 3. The significant positive correlation were obtained between the number of microorganisms and soil chemical properties, available phosphorous, $K^+$, $Mg^{++}$, T-C and soil pH. 4. The number of soil microorganism was in the order of Clay loamy soil > Clayey soil > Loamy soil > Sandy loamy soil.

• Korean Journal of Environmental Agriculture
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• v.33 no.4
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• pp.290-297
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• 2014

BACKGROUND: The current study purposed to analyse the dissipation levels of a neonicotinoid insecticide and clothianidin in paddy and upland soils and clarify the effects of soil moisture on degradation and persistence of the insecticide. METHODS AND RESULTS: In order to achieve the research purposes, clothianidin 8% SG was applied to the paddy and upland fields at the rate of 0.024 kg a.i./10a, while the analytical standard was treated at 0.25 mg/kg soil under laboratory conditions. Based on the multiple first-order kinetics, total clothianidin in soils was dissipated with $DT_{50}$ of 6.7-16.1 and 6.9-8.2 days in the paddy and upland fields, respectively, whereas the figures under the laboratory condition became larger showing 56.3 and 19.6 days. CONCLUSION: As affected by soil moisture, some differences in degradative pathways were observed. Flooding of soil caused evidently demethylation and delayed cyclization of a major metabolite, thiazolylmethylguanidine (TMG) and methylaminoimidazole(MAI), compared to the aerobic upland condition. More than 80% and 50% of the parent compound was dissipated by the 24th day after the final application in both soils and, transformation products had constituted most of soil residues after that.