• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.2
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• pp.43-52
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• 1999

This study was carried out to verify results of the nursery seedbeds. From November of 1997 to September of 1998, the artificial banking slopes in the greenhouse of the College of Agriculture and Life Sciences, Seoul National University were seeded with the mixtures of those species. Most of exotic species showed relatively poor development of root as short as 30cm. Also the green weight of root biomass of the native species was more than two times than that of the exotic species. On the other hand, it was found that the exotic species have relatively well-developed fine roots. Thus, it was concluded that the seed-mixture of the native species with long and thick roots and the exotic species with fine roots be the most effective method for topsoil erosion control on banking-slopes. The artificial rainfall system treatment(30mm/hr, 60mm/hr, 100mm/hr) on $30^{\circ}$ banking-slopes did not cause any significant change in the amount of soil loss by erosion. The root system was best developed in the plot of 1,000 seedlings per square meter and it performed well for soil erosion control. Consequently, in the case of seeding of single herbaceous species without mixing any woody seeds, the expected seedlings were 1,000 to 2,000 per square meter.

• Journal of The Korean Society of Agricultural Engineers
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• v.59 no.2
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• pp.91-99
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• 2017

The objective of this research was to investigate runoff characteristics of suspended solid (SS) and chemical oxygen demand (COD) from a paddy field watershed during storm events in the growing and non-growing seasons. Average of event mean concentration (EMC) of pollutants were 56.9 mg/L for SS and 23.9 mg/L for COD in the non-growing season and 50.3 mg/L for SS and 11.9 mg/L for COD in the growing season. The average EMC of SS in the study area was much lower than that in the uplands irrespective of cultivation, suggesting that paddy fields control soil erosion. This may be because flooding and wet soil in the growing season, and rice straw residue and stubble on the topsoil in the non-growing season reduce soil erosion. The changing tillage practice from fall tillage to spring tillage avoids soil erosion due to shortening of the tilled fallow period. However, the average EMC of COD in the non-growing season was about twice as much that in the growing season likely due to the runoff of organics like rice straw residues. The relationship between SS and COD loads and stormwater runoff volume was expressed by power function. The exponent for SS was higher than that for COD, suggesting that SS load increased with stormflow runoff more than COD load did. The mean SS and COD loads per storm during the non-growing season were much lower than those in the growing season, and therefore non-point source pollution in the growing season should be managed well.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.725-732
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• 2012

There is relatively high vulnerability of soil erosion in slope highland agriculture due to a reclamation of mountain as well as low surface covering during early summer with high rainfall intensity. Especially, in soybean cultivation, soil disturbance by conventional tillage and exposure of topsoil at the early stage of soybean have intensified soil loss. The aim of this study was to evaluate various surface covering methods for reducing soil loss in highland soybean cultivation. The experiment was conducted in 17% sloped lysimeter ($2.5m{\times}13.4m$) with 8 treatments. Amount of runoff water and eroded soil, and soybean growth were investigated. Surface covering through sod culture and plant residue showed 3.4~45.0 runoff water amount with $177{\sim}2,375m^3\;ha^{-1}$ compared with control ($5,274m^3\;ha^{-1}$). And the amount of eroded soil was also reduced by 95% in surface covering treatment with $0.02{\sim}1.94Mg\;ha^{-1}$ than control with $40.72Mg\;ha^{-1}$. Yields of soybean pod showed $0.3Mg\;ha^{-1}$ in rye sod culture, $1.3Mg\;ha^{-1}$ in Ligularia fischeri var. spiciformis Nakai, $0.7Mg\;ha^{-1}$ in Aster koraiensis Nakai, $0.2Mg\;ha^{-1}$ in red clover and $2.0Mg\;ha^{-1}$ in non-covering, on the other hand, covering with cut rye showed $3.8Mg\;ha^{-1}$. Conclusively, covering the soil surface with cut rye were beneficial for reduction of soil loss without decreasing soybean yield in highland sloped fields.