• Journal of The Korean Society of Grassland and Forage Science
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• v.25 no.2
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• pp.137-142
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• 2005

This study was conducted to evaluate the effects of cutting frequency and level of fertilizer application on the botanical composition and forage yield of alpine pasture. Field experiment was established at 600 m (a.s.1) altitude with two cutting frequency schedules (two and three times annually) and two levels of fertilizer application (lower level of fertilizer, 200-200-200 kg / ha and standard level of fertilizer, 280-200-240 kg / ha; N, $P_2O_5$ and $K_2O$, respectively). Higher grass to clover ratio was observed in two cutting frequencies. The clover ratio was highest as $16\%$ in thee cutting frequencies with lower level of fertilizer application End the ratio of weed was low in all treatments ($3.7 {\~} 6.7\%$). No significant difference was observed in forage dry matter (DM) yield among treatments, however forage DM yield in three cutting frequencies tended to be greater in standard level of fertilizer application compared to lower level of fertilizer application. The forage quality was greater in three cutting frequencies, but not changed with different levels of fertilizer application. This result indicates that three cutting frequency and standard level of fertilizer application system are considered to be proper management methods at alpine grassland of 600 m altitude considering the botanical composition, forage DM yield md forage quality.

• The Korean Journal of Pesticide Science
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• v.3 no.3
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• pp.45-53
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• 1999

Red sorrel (Rumex acetosella L.) is a troublesome perennial weed in the alpine grasslands of Kangwon Province of Korea. A number of soil- and foliar-applied herbicides were evaluated for their efficacy of red sorrel control. In greenhouse experiments, no soil-applied herbicides, such as pendimethalin, simazine, alachlor, metolachlor, ethalfluralin controlled red sorrel, however, foliar-applied herbicides, such as glufosinate, paraquat, glyphosate, glyphosate + 2,4-D, dicamba, mecoprop, 2,4-D, bentazone controlled more than 60% of red sorrel 2 weeks after treatments. When dicamba and 2,4-D were applied to red sorrel in different growth stages, the auxin-type of herbicides cold control red sorrel regardless of growth stage. This result implies that the auxin-type herbicides can be applied between early May (early growth stage) and mid lune (before fruit maturation) at Kangwon alpine grasslands. In a field experiment, glufosinate at 1.0 kg a.i, $ha^{-1}$, glyphosate at 3.28 kg a.i. $ha^{-1}$, dicamba at 0.96 kg a.i. $ha^{-1}$, and mecoprop at 150 kg a.i. $ha^{-1}$ controlled more than 80% of red sorrel 4 weeks for treatment, suggesting such herbicides could be applied for red sorrel control at Kangwon alpine grasslands.

• Proceedings of the Korean Society for Rock Mechanics Conference
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• 2008.10a
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• pp.3-16
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• 2008

The underground construction and mining are facing many geomechanics challenges stemming from, geological complexities and stress-driven rock mass degradation processes. Brittle failing rock at depth poses unique problems as stress-driven failure processes often dominate the tunnel behaviour. Such failure processes can lead to shallow unravelling or strainbursting modes of instability that cause difficult conditions for tunnel contractors. This keynote address focuses on the challenge of anticipating the actual behaviour of brittle rocks in laboratory testing, for empirical rock mass strength estimation, and by back-analysis of field observations. This paper summarizes lessons learned during the construction of deep Alpine tunnels and highlights implications that are of practical importance with respect to constructability. It builds on a recent presentation made at the $1^{st}$ Southern Hemisphere International Rock Mechanics Symposium held in Perth, Australia, in September this year, and includes results from recent developments.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.521-526
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• 1998

This study was initiated to build runoff plots, install soil and water quality monitoring systems and collect background data from the plots and soils to assess runoff the nonpoint source pollution and soil physical change in mountainous soils. Eleven 3 $\times$ 15 m runoff plots and monitoring systems were installed at a field of National Alpine Agricultural Experiment Station to monitor soil physical change, and discharge of nonpoint source pollutant. Corn and potato were cultivated under different fertilizer, tillage and residue cover treatments. The soil has a single-layered cluster structure that has a relatively good hydrologic properties and can adsorb a large amount of nutrient. 11 runoff plots were treated and monitored with respect to physical property of the soil, runoff and sediment discharge.

• Korean Journal Plant Pathology
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• v.14 no.4
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• pp.364-366
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• 1998

Bacterial soft rot was occurrenced on stems of cauliflower at a trial field of Alpine Agricultural Experiment Station, Kangwon-Do, Korea. the symptoms began as a small water-soaked lesion, which enlarged rapidly in diameter. The tissue within the affected region became slimy, disintegrating into a mushy mass of disorganized cells. The causal organism was isolated from the diseases lesions and was identified as Erwinia carotovora subsp. carotovora based on the morphological, physiological and chemical characteristics , and on the results of the Biolog program (Biolog Inc., U. S. A.). E. carotovora subsp. carotovora is the first described bacterium which causes bacterial soft rot on cauliflower in Korea.

• KCID journal
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• v.10 no.2
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• pp.62-70
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• 2003

Three small-scale sediment traps were built on sloping potato fields at the alpine belt in Korea to examine the sediment and non-point source pollutant reducing capabilities of the traps. Throughout the research period from January 2002 to December 2002,

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.1242-1246
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• 2010

호우기간 동안 내리는 빗방울의 타격에 의해 흙 입자는 침출수와 함께 이동하여 지표 아래 공극을 막는다. 다져진 지표면은 유출과 토양 유실의 원인이 된다. 발생원으로부터 유실되는 토양을 Polyacrylamide(PAM)과 지표피복재를 이용하여 저감하는 연구를 하였다. PAM은 토양 입자의 결합력을 강화시키고 이탈을 방지하여 토양 유실을 감소시키는데 효과적이다. 이 연구의 목적은 PAM을 덧붙인 볏짚거적, 볏짚거적+톱밥, 볏짚거적+왕겨 등을 이용하여 인공강우 동안 토양 유실을 저감하는 효과를 조사하는 것이다. 실험은 1시간 동안 강우를 모의했으며, 실험 도중에 6~7회 수질 샘플을 채취하였다. 초기유출시간은 총 4차 실험중에 2차를 제외한 나머지에서 볏짚거적+왕겨+PAM이 가장 느리게 유출되었다. SS와 탁도 항목에서 1차 실험을 제외한 나머지 실험에서 볏짚거적+톱밥+PAM이 효과적이었다. 단순히 PAM을 사용하는 것보다 잔여물(residue)을 같이 혼합한 피복재료가 토양 유실과 유출을 저감하는데 더욱 효과적인 것으로 나타났다. 본 연구 결과는 향후 농촌지역에 토양 유실저감에 필요한 자료로 활용할 수 있을 것이라 판단된다.

• Journal of The Korean Society of Agricultural Engineers
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• v.53 no.5
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• pp.9-16
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• 2011

Curve Numbers (CN) for the combination of land use and hydrologic soil group were regionalized at Imha Watershed using Long-term Hydrologic Impact Assessment (L-THIA) coupled with SCE-UA. The L-THIA was calibrated during 1991-2000 and validated during 2001-2007 using monthly observed direct runoff data. The Nash-Sutcliffe (NS) coefficients for calibration and validation were 0.91 and 0.93, respectively, and showed high model efficiency. Based on the criteria of model calibration, both calibration and validation represented 'very good' fit with observe data. The spatial distribution of direct surface runoff by L-THIA represented runoff from Thiessen pologen at Subi and Sukbo rain gage station much higher than other area due to the combination of poor hydrologic condition (hydrologic soil C and D group) and locality heavy rainfall. As a results of hydrologic condition and treatment for land use type based on calibrated CNs, forest is recommended to be hydrologically modelled dived into deciduous, coniferous, and mixed forest due to the hydrological difference. The CNs for forest and upland showed the poor hydrologic condition. The steep slope of forest and alpine agricultural field make high runoff rate which is the poor hydrologic condition because CN method can not consider field slope. L-THIA linded with SCE-UA could generated a regionalized CNs for land use type with minimized time and effort, and maximized model's accuracy.

• Journal of The Korean Society of Agricultural Engineers
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• v.49 no.2
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• pp.49-60
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• 2007

The alpine agricultural activities are usually performed at higher and steep areas in nature. Thus, significant amounts of soil erosion are occurring compared with those from other areas. Thus, the soil erosion induced environmental impacts in these areas are getting greater. The Doam watershed is located at alpine areas and it has been well known that the agricultural activities in the watershed are causing accelerated soil erosion and water quality degradations. Many modeling approaches were employed to solve soil erosion and water quality issues. In this study, the Soil and Water Assessment Tool (SWAT) model was utilized to simulate the hydrologic and sediment behaviors in the Doam watershed. In many previous modeling studies, the digital soil map and its corresponding soil properties were used without modification to reflect soil conditioning at many agricultural fields of the Doam watershed. Thus, the soil sample was taken at the agricultural field within the Doam watershed and analyzed for its physical properties. In this study, the digital topsoil properties in the agricultural fields within the Doam watershed were replaced with the soil properties for reconditioned soil analyzed in this study to simulate the impacts of using soil properties for reconditioned soil in hydrologic and sediment modeling at the Doam watershed using the SWAT model. The hydrologic component of the SWAT model was calibrated and validated for measured flow data from 2002 to 2003. The $R^2$ value was 0.79 and the EI value was 0.53 for weekly simulated data. The calibrated model parameters were used for hydrologic component validation and the $R^2$ value was 0.86 and the EI value was 0.74 for weekly data. For sediment comparison, the $R^2$ value was 0.67 and the EI value was 0.59. These statistics improved with the use of soil properties of the reconditioned soil in the field compared with the results obtained without considering soil reconditioning. The simulated sediment amounts with and without considering the soil properties of the reconditioned soil were 284,813 ton and 158,369 ton, respectively. This result indicates that there could be approximately 79% of errors in estimated sediment yield at the Doam watershed, although the model comparison with the measured data gave similar satisfactory statistics with and without considering soil properties from the reconditioned soil.

• The Korean Journal of Pesticide Science
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• v.10 no.1
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• pp.50-55
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• 2006

A field-resistant strain of the diamondback-moth(Plutella xylostella L.), collected from Chinese cabbage alpine farmland at Gangwon-do, Korea, was used for determination of the characteristics of resistance to chlorpyrifos using the activities of esterases and glutathione-S-transferase(GST), protein sequestration and AChE insenstivity. Although the activities of esterases extracted from resistant strain and susceptible strain were not significantly different, isozyme bands shown on the electrophoresis were different. GST activity from field resistant strain was 1.5-fold higher than that of susceptible. No differences were shown between resistant and susceptible ones in protein sequestration. The insensitivities of AChE to chlorpyrifos, however, extracted from susceptible strain was 460-fold higher than those of resistant. These results indicated that the insensitivity of AChE is the major factor for developing the resistance and activities of GST might be a minor factor.