• Korean Journal of Soil Science and Fertilizer
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• v.35 no.1
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• pp.1-11
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• 2002

Root distribution was monitored in the root zone of corn fields on several soil series in central Illinois during three growing seasons in order to find the effect of soil series and tillage system on root growth. A minirhizotron technique was used to videotape each soil profile in weekly intervals to a depth of 75 cm under conventional tillage (CT) and no tillage (NT) systems of cultivation. Root distribution near soil surface generally increased during the early stages of the growing season, but declined as surface soil moisture was depleted in late summer. Even though root distribution was not significantly different between soil series in this experiment. differences in root distribution between soil series were associated with the increases in root-available water storage capacity. Root population in the top 30 cm of NT plots. where increased water infiltration rates and saturated flow of soil moisture into the subsoil, was generally higher than that of CT plots in Illinois corn fields. Foots appeared in the deeper layers later in the growing season, with root penetration into subsoil layers occurring as much as 2-3 weeks earlier on the NT plots than in CT plots. In conclusion, root distribution was significantly affected by the tillage systems, but not different by soil series.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.72-72
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• 2017

국내 농업에서 토양의 반전, 쇄토, 배토, 가능한 복합작업기인 무동력 디스크해로우 방식의 경운과 배토 고효율 복합작업기의 수요가 증가 하고 있다. 경운작업에서 일련의 과정은 작물의 생육과 관리차원에서 큰 의미를 지니며 작물재배의 첫 단계로 중요시 다루어져야할 과정이다. 이러한 작업기의 성능 시험에서 포장시험을 통해 복합기의 신뢰도와 실제 필드에서 발생하는 문제들을 포괄적으로 해결 할 수 있는 방안이 필요하다. 토양 경작을 위한 농업기기의 작업 저항은 식물 생산에서 유용성을 평가하는 가장 중요한 지표중 하나이다. 작업 저항(수평, 수직 방향의 힘)은 트랙터의 힘에 의해 생성된 동작을 방해하므로 토양 경운 시 에너지 소비를 결정하고 설계 매개 변수 측면에서 최적의 작업 조건을 결정하는 데 중요한 영향을 미친다. 따라서 본 연구에서는 경상대학교 내 위치한 실험동에서 Soil-bin에 이송장치를 설치한 후, 이송장치에 디스크 해로우 (Multidisc Vario, Tulip Agri., Netherlands)를 부착하여 실험을 진행하였다. 디스크 해로우의 원주 평면과 수직 평면 사이의 각 a(토양 표면에 수직)와 디스크의 해로우의 원주 평면과 작업 방향 사이의 각 b의 값을 독립 변수로 두고 a, b를 변화 시키면서 발생하는 이송장치의 견인력을 측정하여 농가 및 효율적인 경운작업 시 기초자료로 활용하고자 한다.

• Korean Journal of Environmental Agriculture
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• v.3 no.2
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• pp.23-29
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• 1984

Agricultural soil samples collected from 121 sites (plastic film house 59, up-land 30 and orchard 32 sites) were evaluated by steam distillation and GLC-ECD analysis for organochlorine pesticides (${\gamma}-BHC$, heptachlor, p,p'-DDE, dieldrin, p,p'-DDD, and p,p'-DDT) in Jeollanam-Do area. Total residues of organochlorine pesticide in orchard, plastic film house and up-land were 0.415, 0.234 and 0.156ppm, respectively. Ninety-four percent of total residue was p,p'-DDT and its homologues (p,p'-DDE and p,p'-DDD). ${\gamma}-BHC$ was detected in all soil samples at $trace{\sim}0.050ppm$ range. Residue levels of organochlorine pesticide increased in the order of p,p'-DDE, ${\gamma}-BHC$, heptachlor, dieldrin, p,p'-DDT and p,p'-DDD.

• Korean Journal of Environmental Agriculture
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• v.21 no.2
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• pp.117-121
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• 2002

This study was conducted to find out the effect of municipal sewage sludge on the growth and heavy metal content of rose and soil chemical properties. Municipal sewage sludge was applied to soil at rate of 0, 3, 5, 10 and 15 ton/10a, the plant height, flower number and stem size of rose were found to be increase in the treatments of sewage sludge. Contents of mineral nutrients in rose stem were determined to be higher at municipal sewage sludge application plots than those of no application. But, there were not any significant increases of heavy metal contents in soil and rose stem with the sludge applications. from the results of this study, it is apparent that the application of municipal sewage sludge would not increase available heavy metals in soil.

• Journal of Soil and Groundwater Environment
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• v.21 no.1
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• pp.94-103
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• 2016

Landfarming that supplies aerobic biodegradation condition to indigenous microbes in soils is a biological remediation technology. In this research, volatilization and biodegradation rate by indigenous microbes in the soil contaminated with total petroleum hydrocarbons (TPH) were measured. Soils were contaminated with diesel artificially and divided into two parts. One was sterilized by autoclave to remove indigenous microorganism and the other was used as it was. Various moisture contents and number of tillings were applied to the soil to find out proper condition to minimize volatilization and enhance bioremediation. Volatilization of TPH was inhibited and biodegradation was enhanced by increase on moisture content. Tilling was usually used to supply air for microbes, but tillings did not affect the growth of microbes in our study. Enough moisture content and proper aeration are important to control volatilization in landfarming. Also, TPH degradation was a function of the microbe counts (x₁), numbers of tilling (x₂), and moisture content (x₃) from the application of the response surface methodology. Statistical results showed the order of significance of the independent variables to be microbe counts > numbers of tilling > moisture content.

• Journal of Soil and Groundwater Environment
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• v.29 no.1
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• pp.51-62
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• 2024

A study was performed to investigate the positive impacts of humic substances (HS) on the growth of green barley, a type of green manure plant. The study was conducted in a pot culture using two different types of reclaimed soils that had been treated by land farming (DDC) and thermal desorption (YJ) methods, respectively. The experimental conditions consisted of three treatments: plant only (P), plant plus 2% HS, and no plant (control). After 89 days of culture in a controlled growth chamber, the growth of spring barley and activity of seven soil enzymes were measured. The results indicated that the addition of HS had a substantial (p<0.10) positive effect on shoot biomass in both types of soil. Furthermore, the addition of HS notably (p<0.05) enhanced all seven soil enzyme activities in both soils. Both the aboveground and belowground parts of barley plants were returned to soil and aged for 10 weeks in the same growth chamber, which resulted in notable enhancement in soil health indicators. These improvements included an increase in organic matter, a drop in bulk density, and an increase in the activity of seven different soil enzymes. When lentil seeds were planted in the aged soils, the development of the seedlings was more vigorous than that in the control in both soils, although allelopathy of barley suppressed lentil germination in soil with pH 7.0 but not in soil with pH 8.5.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1586-1590
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• 2006

In order to calculate the actual erosion according to the universal soil loss equation (USLE) and to estimate the impact of land use on soil erosion in Saemangeum, it is important to know the C-factor. Based on the USLE crop-growth stages, the cover-management C-factors were calculated for the main crop and crop rotation systems by National Institute of Agricultural Science and Technology. Combining this result with statistical data about crop cultivation area and crop rotation systems, C-factors of each administrative district in Saemangeum watershed were calculated. The range of C-factors were between 0.28 and 0.35. High C-factor value was obtained with Gimje (C = 0.35) and small C-factor values were found in Wanju (C = 0.28) and Jeongeup (C = 0.29). With this result, calculated annual soil loss was 2,804,483 ton per year. Because of the lack of sufficient statistical data about crop rotation systems, further studies are required on collecting field survey data.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.306-306
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• 2022

2015년부터 2019년까지 우리나라에서는 평균 18,521 ha의 경작지에 가뭄피해가 발생하였다. 이 중 평균 11,260 ha는 밭으로 피해의 60% 이상이 밭에서 발생하는 것으로 나타났다. 밭 가뭄 피해는 2016년과 2018년에 크게 발생하였으며, 제주에서 가장 큰 피해가 발생하였다. 또한 강원도, 충청남도의 여러 지역에서 지속적인 피해가 나타났다. 농업 가뭄을 대응하기 위하여 저수지와 지하수 관정 등을 활용하고 있지만, 밭에 대한 구체적이고 체계적인 가뭄 대응 방안은 미비하다. 따라서 본 연구에서는 밭 가뭄에 대한 취약성을 지역별로 평가하고 이를 기반으로 우선 관리지역을 선정하는 방안을 검토하였다. 밭 가뭄 취약성 평가에는 위협 요인, 피해 요인, 해소 요인을 평가 기준을 설정하였다. 밭 가뭄에 대한 위협 요인은 토양 수분량의 정도로 제시할 수 있으며 본 연구에서는 1995년부터 2014년까지 20년간의 강수량, 증발산량 등의 기상 및 토양 자료를 활용하여 분석하였다. 피해 요인은 피해를 입는 밭이 대상으로 행정구역 단위로 평가를 수행함에 따라 행정구역별 밭 비율을 산정하여 활용하였다. 해소 요인은 가뭄 피해를 감소시킬 수 있는 활동을 반영하는 평가 기준으로서 본 연구에서는 저수지와 지하수관정 등 밭 가뭄 저감에 활용할 수 있는 요소를 반영하였다.

• The Korean Journal of Pesticide Science
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• v.15 no.2
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• pp.160-165
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• 2011

Monitoring of pesticide residues were conducted at three sites in the Southern Area of Seoul, Korea (Gang-nam, Gang-dong and Song-pa). We measured pesticide residues within soil samples using multi-pesticide residues analysis. Samples were collected at the three sites with 60 sampling spots. The amount of pesticide residues in the soil samples were as follows [(minimum-maximum), mg/kg] endosulfan 0.002-0.999, procymidone 0.002-1.200, diazinon 0.003-0.024, metalaxyl 0.012-0.075. In soil treated with 0.445 mg/kg of endosulfan, the pesticide absorbed by chamnamul, was 0.157 mg/kg (Absorption rate : 35.3%). However, in soil treated with 0.358 mg/kg of endosulfan, the pesticide absorbed by lettuce, was 0.004 mg/kg (Absorption rate : 1.1%).

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.2
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• pp.59-64
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• 2006

To analyze the changes of soil physico-chemical properties after reclamation, we carried out an experiment for 75 samples of representative saline soils in South Korea. The more the years after reclamation is proceeded, the blighter the soil color is, soil horizon differentiation and structure is developed, but electrical conductivity(EC) decreased. After the soil survey, coarse textured soils were more quickly de-salined than the fine textured soils. In case of fine loamy textured Poseung series, it could be estimated that the series had Salic horizons in sub-order level of taxonomical classification. In other case of coarse loamy textured soil series, it could be estimated that the series had Sodic properties in sub-group level. Sodium contents of fine loamy textured soils were not decreased after reclamation, but those of coarse loamy textured Gwanghwal series reclaimed about 76 years ago were reclassified because of desalinization. To be desalined low to 4 dSm-1 of EC, it presumably takes about 108, or 12 years for fine loamy and coarse loamy textured soils, respectively.