• Journal of Korean Society of Forest Science
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• v.24 no.1
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• pp.1-24
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• 1974

A national programme of erosion control for soil and water conservation needs to be based on factual information about rates and quantities of soil erosion and of water runoff. The best and simplest way of reducing sedimentation pollution is to prevent or control the erosion at its sources. Steeply sloping earth banks are liable to both surface erosion and land-slides and the key to the control of these form of erosion lies with drainages and dense vegetation establishment including surface mulching on the slopes. Micro-plots having $1.6m^2$ (1 metre in width and 1.6 metres in slope length, and 1:1.2 in gradient) of banking slopes on the coarse sand soil are used to establish the order of magnititude of the difference in controlling of soil erosion and water runoff, and in potentiality of execution in consideration of the values of landscapes, performed on the 2 repetetions of six-experiment plots consisted of five surface mulches including seedings and one bare slope as a control treatment. The main results obtained may be summarized as follows: 1. The significant difference is realized in the quantities of soil erosion between the measures of six treatments. 2. Excepting the differences between treatment III and VI, the significant difference is realized in the rate of surface runoff between each treatment measures. 3. Both measures of treatment II and IV are recognized as the most effective measures in controlling the soil erosion and water runoff and also in establishing the ground vegetation. (Treatment II is a measures of the coarse straw-mat mulchings on the micro-strip seedings, Treatment IV is a measures of the "SPRAY-ON method" on the micro-strip seedings). In consideration of the potentiality of execution as well as the value of landscapes, the measures of treatment II could be recommendable for establishing the vegetation cover on the denuded gentle slopes in hillsides while the measures of treatment IV could be suitable for accelerating the establishment of vegetation on steeply sloping earth banks and cuts.

• The Korean Journal of Pesticide Science
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• v.10 no.4
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• pp.279-288
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• 2006

Three different experiments were undertaken to investigate the runoff and erosion loss of diazinon and metolachlor from sloped-field by rainfall. The mobility of two pesticides and which phase they were transported by were examined in adsorption study, the influence of rainfall pattern and slope degree on the pesticide losses were evaluated in simulated rainfall study, and the pesticide losses from soybean field comparing with bare soil were measured in field lysimeter study. Freundlich adsorption parameter (K) ranged $1.6{\sim}2.0$ for metolachlor and $4.0{\sim}5.5$ for diazinon. The K values of pesticides by the desorption method were higher than those ones by the adsorption method. Another parameter (1/n) in Freundlich equation for the pesticides tested ranged $0.96{\sim}1.02$ by desorption method and $0.87{\sim}1.02$ by adsorption method. By the SSLRC's classification for pesticide mobility of diazinon and metolachlor were classified as moderately mobile ($75{\leq}Koc$ <500). Runoff and erosion losses of pesticides by three rainfall scenarios were $0.5{\sim}1.0%$ and $0.1{\sim}0.7%$ for metolachlor and $0.1{\sim}0.6%$ and $0.1{\sim}0.2%$ for diazinon. Distribution of pesticides in soil polite were investigated after the simulated rainfall events. Metolachlor was leached to $10{\sim}15$ cm soil layer and diazinon was leached to $5{\sim}10$ cm soil layer. Losses of each pesticide in the 30% of sloping degree treatment were $0.2{\sim}1.9$ times higher than those ones in the 10% of sloping degree treatment. Pesticide losses from a series of lysimeter plots in sloped land by rainfall ranged $1.0{\sim}3.1%$ for metolachlor and $0.23{\sim}0.50%$ for diazinon, and were $1/3{\sim}2.5$ times to the ones in the simulated rainfall study. The erosion rates of pesticides from soybean-plots were $21{\sim}75%$ lower than the ones from bare soil plots. The peak runoff concentration in soybean-plots and bare soil plots were $1{\sim}9{\mu}gL^{-1}$ and $3{\sim}16{\mu}gL^{-1}$ for diazinon, $7{\sim}31{\mu}gL^{-1}$ and $5{\sim}40{\mu}gL^{-1}$ for metolachlor, respectively.

• Journal of Korean Society of Forest Science
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• v.29 no.1
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• pp.54-101
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• 1976

This study was conducted on the major factors affecting soil erosion and surface run-off. In order to investigate the processes and mechanisms of soil erosion on denuded forest-land in Korea, and to systematize the magnitudes of influences and interactions between individual factors, the five major factors adopted in these experiments are soil textures (coarse sand and clay loam), slope steepness ($10^{\circ}$, $20^{\circ}$, $30^{\circ}$ and $40^{\circ}$), rainfall intensities (50, 75 and 100mm/hr), slope mulching methods (bare, coarse straw-mat mulching, grass mulching and anti-erosion liquid mulching) and vegetation densities (sparse, moderate and dense). The processes and mechanisms of soil erosion, and the effects of mulchings on soil erosion as well as surface run-off rates were studied algebraically with four parts of laboratory experiments under the simulated rainfall and another part of field experiment under the natural rainfall. The results in this study are summarized as follows: 1. Experiment factors and surface run-off rates The surface run-off rates under the natural rainfall were resulted about 24.7~28.7% from the bare slopes, about 14.0~16.4% from the straw-mat mulched slopes, about 7.9~9.1% from the liquid mulched slopes, and about 5.6~7.2% from the grass mulched slopes respectively. The surface run-off rates under the simulated rainfall differed greatly according to the rainfall intensity and the mulching method. 2. Magnitudes of influences and interactions of the individual factor on the surface run-off rates. The experimental analyses on the major factors(soils, slopes, rainfalls, mulchings and vegetations) affecting the rates of surface run-off, show that the mean differences of surface run-off rate are significant at 5% level between the soil texture factors, among the slope steepness factors, among the rainfall intensity factors, among the mulching method factors, and among the vegetation density factors respectively. The interactions among the individual factor have a great influence(significant at 1% level) upon the rate of surface run-off, except for the interactions of the factors between soils and slopes; between slopes and vegetations; among soils, slopes and rainfalls; and among soils, slopes and mulchings respectively. On the bare slopes under the simulated rainfall, the magnitude of influences of three factors(soils, slopes and rainfalls) affecting the rate of surface run-off is in the order of the factor of rainfalls, soils and slopes. The magnitude of influences of three factors (soils, rainfalls and mulchings) affecting the rate of surface run-off, on the mulched slopes under the simulated rainfall is in the order of the factor of mulchings, rainfalls and soils and that of influences of the factor of soils, slopes and mulchings is in the order of the factor of mulchings, soils and slopes. On the vegetation growing slopes under the simulated rainfall, the magnitude of influences of three factors (soils, slopes and vegetations) affecting the rate of surface run-off is in the order of the factor of vegetations, soils and slopes. In the same condition of treatments on the field experiment under the natural rainfall, the order of magnitude of influences affecting the rate of surface run-off is the factor of mulchings, soils and slopes. 3. Experiment factors and soil losses The soil losses of the experiment plots differed according to the factors of soil texture, slope steepness, rainfall intensity and mulching method. The soil losses from the coarse soil were increased about 1.1~1.3 times as compared with that of fine soil under the natural rainfall, while the soil losses from the fine soil were increased about 1.2~1.3 times compared with that of coarse soil under the simulated rainfall. The equation of $E=aS^b$ (a, b are constant) between the slope steepness (log S) and soil losses (log E) under the simulated rainfall were developed. The equation of $E=aI^b$ (a, b are constant) between the rainfall intensity (log I) and soil losses (log E) were developed, and b values have a decreasing tendency according to the increase of the slope steepness and rainfall intensity. The soil losses under the natural rainfall were appeared about 38~41% from the coarse straw-mat mulched slopes, about 20~22% from the liquid mulched slopes, about 14~15% from the grass mulched slopes as compared with that of the bare slopes respectively. The soil loss from the vegetation plots showed about 7.1~16.4 times from the sparse plot, about 10.0~17.9 times from the moderate plot and about 11.1~28.1 times from the dense plot as compared with that of the bare slopes. 4. Magnitudes of influences and interactions of the individual factor on the soil erosion. The experimental analyses on the major factors(soils, slopes, rainfalls, mulchings and vegetations) affecting the soil erosion, show that the mean differences of soil losses are highly significant between the soil texture factors, among the slope steepness factors, among the rainfall intensity factors, among the mulching method factors and among the vegetation density factors respectively. The interactions among the individual factor have mostly great influences upon the soil erosion. The magnitude of influences of three factors (soils, slopes and rainfalls) affecting the soil erosion on the bare slopes under the simulated rainfall is in order of the factor of rainfalls, soils and slopes. On the mulched slopes under the simulated rainfall, the magnitude order of influences of three factors(soils, rainfalls and mulchings) affecting the soil erosion is the factor of mulchings, rainfalls and soils, and the order of influences of factor of soils, slopes and mulchings is the factor of mulchings, soils and slopes. On the vegetation growing slopes under the simulated rainfall, the magnitude of influences of three factors (soils, slopes and vegetations) affecting the soil erosion is in the order of the factor of slopes. vegetations and soils. In the same condition of treatments on the field experiment under the natural rainfall, the order of magnitude of influences of three factors (soils, slopes and mulchings) affecting the soil erosion is the factor of mulchings, of slopes and of soils.

• Korean Journal of Environment and Ecology
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• v.35 no.2
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• pp.135-153
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• 2021

The demilitarized zone (DMZ) is a border barrier with 248 kilometers in length and about 4 kilometers in width crossing east to west to divide the Korean Peninsula about in half. The boundary at 2 kilometers to the south is called the southern limit line. The DMZ has formed a unique ecosystem through a natural ecological succession after the Armistice Agreement and has high conservation value. However, the use of facilities for the military operation and the unchecked weeding often damage the areas in the vicinities of the southern limit line's iron-railing. This study aimed to prepare basic data for the restoration of damaged barren vegetation. As a result of classifying vegetation communities based on indicator species, 10 communities were identified as follows: Duchesnea indica Community, Hosta longipes Community, Sedum kamtschaticum-Sedum sarmentosum Community, Potentilla anemonefolia Community, Potentilla fragarioides var. major Community, Prunella vulgaris var. lilacina Community, Dendranthema zawadskii var. latilobum-Carex lanceolata Community, Dendranthema zawadskii Community, Plantago asiatica-Trifolium repens Community, and Ixeris stolonifera-Kummerowia striata Community. Highly adaptable species can characterize vegetation in barren areas to environment disturbances because artificial disturbances such as soil erosion, soil compaction, topography change, and forest fires caused by military activities frequently occur in the barren areas within the southern limit line. Most of the dominant species in the communities are composed of plants that are commonly found in the roads, roadsides, bare soil, damaged areas, and grasslands throughout South Korea. Currently, the vegetation in barren areas in the vicinities of the DMZ is in the early ecological succession form that develops from bare soil to herbaceous vegetation. Since dominant species distributed in barren land can grow naturally without special maintenance and management, the data can be useful for future restoration material development or species selection.

• Journal of Korean Society of Forest Science
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• v.61 no.1
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• pp.69-79
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• 1983

To develope the fundamental models suitable for slope stabilization and scenic effect improvement of the roadside slopes, this study has continuously been conducted for last about 10 years through the field survey and observations on the roadside slopes of 100 plots located in the Capital region. The results obtained could be summarized as follows: 1) In general, due to unsuitable treatments and constructions to the man-made bare slope characteristics of the roadsides, the treatment aims for stabilizing and improving the scenic beauty of the slopes have not been successfully reached in the surveyed regions. 2) Particularly, because of insufficiency of the follow-up maintenance techniques to the roadside slopes treated, denudations of slope scenery established as well as the withering of the vegetation planted have been accelerated for the most part of the slopes treated. 3) 6 fundamental models for the roadside slope treatments have been developed and could be edaptable to the nation-wide purposes. The fundamental models are the model of forest scenery match plantation, roadside scenery establishment, denuded land rehabilitation, rock slope greenification, absolute stabilization, and environmental plantation belt establishment, respectively.