• Korean Journal of Soil Science and Fertilizer
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• v.4 no.2
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• pp.155-159
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• 1971

1. Based upon an fertilizer experiment done in a farmer's field, with a medium maturity variety, Jinheung, (in 1969) a method of determination of nitrogen to be additionally given, at tillering and reproductive stages was studied. In this experiment, four kilograms of nitrogen per 0.1 ha was applied as basal dressing to all experimental treatments at transplanting time. 2. The application of nitrogen at the reproductive stage of paddy increased the yield remarkably and cut down the amount of nitrogen to be given at the tillering stage. The yield of paddy, 670kg/0.1 ha obtained by the application of 6.82kg N/0.1 ha at the reproductive stage far exceeded the yield, 644kg/0.1ha obtained when over 8kg N/0.1ha of N is applied at tillering stage alone. This emphasizes the importance of nitrogen top dressing at the reproductive stage. 3. As the amount of nitrogen to be given at both stages, reproductive and tillering, would be the reflection of soil fertility of the field, a correlative study between the amount of nitrogen to be given at both stages and soil analysis is suggested to be undertaken. 4. A study on the relationship between the amount of fertilizer to be given at stages different growth and yield components is suggested to be undertaken for the purpose of establishing a better fertilizer use technique.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.5
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• pp.333-343
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• 2003

This experiment was carried out to improve the utilization of liquid pig manure (LPM) for rice at the two textures of valley soil in 2000 and 2001. The soil textures were coarse loamy and fine loamy in Sachon and Jisan series, respectively. Treatments consisted of no fertilized plot, chemical fertilized plot, LPM 150%, LPM 100%, LPM 100%+NK (top dressing) 30%, LPM 70%+NK 30%, LPM 50%+NK 50% plot. LPM was applied as basal fertilizer compare to nitrogen of chemical fertilized plot. Total N contents in the LPM were 6.0 and $4.5g\;kg^{-1}$ in 2000 and 2001, respectively. After the experiment, P and K contents of soils were not difference between chemical and LPM application plots. But heavy metal contents in soils were slightly higher in LPM application plots than in chemical fertilized plot. Immediately after LPM application, ammonia gas content was $18mg\;kg^{-1}$ in LPM 150% plot, but it was $3mg\;kg^{-1}$ in LPM 50% plot. Two days after LPM application, ammonia gas content was 3 times higher in coarse loamy than in fine loamy soil. After rotary tillage, ammonia gas was not detected at all LPM treatments. This result suggests that rotary tillage can reduce the nasty smell of LPM quickly. Inorganic nitrogen, $NO_3$ and $NH_4$, contents in water of paddy was higher at coarse loamy soil from rice transplanting to tillering stage. After that season, inorganic nitrogen contents of water were not different according to soil texture and treatments. Content of $NH_4-N$ in soil solution was higher at LPM plots than chemical fertilizer plot. Total nitrogen contents in rice plant after harvesting were higher at chemical fertilization plot than LPM application plot, but K contents showed an opposite tendency. Rice yield was decreased only in LPM plots at two soil textures. But yield was not significantly difference between chemical fertilizer and LPM+top dressing plots at coarse loamy soil and increased 5% at LPM 50%+NK 50% plot at fine loamy soil in 2001.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.2
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• pp.81-92
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• 2017

Recently, agricultural lands have decreased sharply, which was caused by huge housing site, urbanization, land consolidation, and road construction etc. In particular, Yangju city near Seoul city has the most severe land use change in Korea. Therefore, we analyzed changes of land use, soil properties, and soil information in order to provide the basic soil information and soil management practices in this city. The area of crop cultivated land in Korea (2015) reduced by 12,090 ha compared to ones from the previous year (2014). The paddy field decreased by 25,421 ha but, upland field increased by 13,331 ha. One of the reasons for the reduction of the paddy field was converting paddy field to upland (20,916 ha) > others (3,056) > building (2,571) > public facilities (847) > idle land (217). But, reasons for increase of upland field were switching paddy to upland (20,916 ha) > land developed (634). The main reason of converting paddy field to upland was changing from rice to more profitable speciality crops or pulses. The cropland area (paddy fields, upland, orchard) of Yangju city reduced by 1,412 ha (2015/2014). The ratio of cropland area in each city reduced by 22.9% dramatically compared 2015 to 1999. The paddy fields located in alluvial plains in Yangju city were changed into upland or green house. The drainage classes of soil have been deteriorated because the flows of water were intercepted by road construction and other disturbance to water flows. In particular, paddy fields have been changed to not only upland, orchard, greenhouse cultivation but also to fallow and soil dressing on paddy in Yangju city. To analyze result of soil survey of Yangju city, 858 soil codes (soil phases) were used and the area was 105.17ha. The number of soil series increased from 60 to 65, and that of soil phase increased from 105 to 124. The largest increased area was Noegog soil series. 125.7ha of Neogog soil series was incorporated from the existing Sachon, Yecheon and Eungog soil series. The soil suitability class of paddy field in Ogjung huge housing site of Yangju city was the 4th grade for 32.6% of the area. The soil suitability classes of upland were 2nd and 3rd grade for 72.4% of the area. Farm land with high quality should be conserved by related law.

• Korean Journal of Agricultural Science
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• v.50 no.2
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• pp.273-281
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• 2023

Ammonia (NH₃) emitted from the use of fertilizers during agricultural practice generates particulate matter and odors. The application of carbonized rice husk, an eco-friendly material, is one of the measures used to reduce NH₃. The objective of this study was to evaluate the effect of the application rate and pH of carbonized rice husk on NH₃ emissions and soil quality. An experiment to assess NH₃ emissions was performed in a glasshouse using a static chamber method. The pH of the carbonized rice husk was divided into acidic, neutral, and basic groups, and the carbonized rice husk application rates were 1, 3, and 5% of the soil weight. NH₃ emissions showed a sharp increase within three days after the inorganic fertilizer was applied. Subsequently, NH₃ emissions decreased rapidly after basal fertilization compared to primary and secondary top-dressing. When carbonized rice husks were applied to soil, NH₃ emissions decreased in all treatments, and neutral carbonized rice husk was the most effective in comparison with acidic and basic carbonized rice husk. The application rate of carbonized rice husk and NH₃ emissions showed a negative correlation, and the lowest emissions were found in units with a 5% application rate. Also, there was no statistically significant difference between NH₃ emissions according to the application rate of carbonized rice husk, and when carbonized rice husks were applied at a 5% rate, soil OM increased excessively. Therefore, it is recommended to apply only 1% neutral carbonized rice husk to most effectively reduce NH₃ emissions in the soil.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.6
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• pp.351-356
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• 2006

A long-term experiment was initiated in 1979 at Experiment Farm of Honam Agricultural Research Institute, to investigate the effects of continued use of organic matter (rice straw and compost) along with different levels of nitrogen fertilizer in rice cultivation. The soils of experimental plots is classified as Jeonbug series developed on Fluvio-marine deposits. The application rates of rice straw and compost were 5 Mg/ha/year and 10 Mg/ha/per year, respectively. The fertilizer N application rates per season were 0, 100, 150, 200, and 250 kg/ha. In 2002, after 24 years of experiment, the effect of different treatments on soil pH, characteristics soil organic matter, soil N and P were investigated. The results of the study is summarized as following. The continue use of organic matter tended to lower the soil pH, to increase organic matter and available phosphate contents. The rice straw tended to lower soil pH more than compost, while the effect of compost was greater in increasing soil organic matter and available soil P then rice straw. The application of organic matter resulted in the increase in total organic N in the soil. Such effect was greater in compost application than in rice straw application. In organic N, greatest was amino acid-N, followed by unidentifiable organic N. The least was amino sugar-N. The application of organic matter with and without nitrogen fertilizer affected the in organic fractions of P, particularly Fe-P and Al-P. The application of rice straw tended to increase Ca-P.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.6
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• pp.361-371
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• 2002

Multifunctionality of agriculture has been an important international issue in terms of environmental benefits and public concerns. We calculated soil loss mass in national basis using the USLE, and attempted to evaluate its economical benefits by replacement cost method. Soil loss mass ranged from 1.4 to $18MT\;ha^{-1}\;yr^{-1}$ was fairly fitted to measured values for 13 cropping systems. In national basis, the factors in USLE were evaluated as: 429.4 for rainfall and runoff factor. R, 0.15 for soil erodibility factor, K, 1.72 for topographic factor, LS, 0.275 for cover and management factor, C, and 0.856 for support practice factor, P. The soil loss estimated from upland farming using the USLE was $26.1MT\;ha^{-1}\;yr^{-1}$, but soil loss from the bare soil was $110.8MT\;ha^{-1}\;yr^{-1}$, the ratio of soil loss from upland farming to bare soil was 23 percents. Function of reducing soil loss in comparison with the bare soil was $84.7MT\;ha^{-1}\;yr^{-1}$, of which national soil loss mass was 62.6 million MT per annum in south Korea. Agriculture economic replacement cost of soil loss reduction was 497 billion Wons(398 million dollars) for the cost of upland soil dressing. For conservational purposes to increase the environmental benefits of upland farming, the agricultural practice including contour, strip cropping, terracing and division ditches should be implemented.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.749-759
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• 2012

A field experiment was conducted to selection of ground-based remote sensor and reflectance indices to estimate rice production, estimation of suitable season for ground-based remote sensor and N top dressing fertilizer application rate in 2010. Fertilizer application was determined by "Fertilizer management standard for crops" (National Academy of Agricultural Science, 2006). Four levels of N-fertilizer were applied as 0%, 70%, 100% and 130% by base N-fertilizer application and were fertilized as 70% of basal dressing and 30% as top dressing. Rice (Oryza sativa L.) of Chucheong and Joonam (Korean cultivar) were planted on May 22, 2010 in sandy loam soil and harvested on October 6, 2010. Reflectance indices were measured 7 times from July 5 to August 23 by Crop circle-amber and red version and GreenSeeker-green and red version. Remote sensing angle from the sensor head to the canopy of rice was adjusted to $45^{\circ}$, $70^{\circ}$ and $90^{\circ}$ degree because of difference in the density of plant and the sensing angle. The reflectance indices obtained ground-based remote sensor were correlated with the biomass of rice at the early growth stage and at the harvest with $70^{\circ}$ and $90^{\circ}$ degree of sensor angle. The reflectance indices at the 52th Day After Transplanting (DAT) and the 59th DAT, critical season, were positively correlated with dry weight and nitrogen uptake. Specially NDVI at the 59th was significantly correlated with the mentioned parameters. Based on the result of this study, rNDVI by GreenSeeker on $70^{\circ}$ degree of angle at the 59th DAT in Chucheong and rNDVI by Crop Circle on $70^{\circ}$ degree of angle and gNDVI by GreenSeeker on $70^{\circ}$ degree of angle at the 59th DAT in Joonam can be useful for estimation of dry weight and nitrogen uptake. Moreover, sufficiency index estimated by reflectance index at the 59th DAT can be useful for the estimation of N-fertilizer level application and can be used as a model for N-top dressing fertilizer management.

• Journal of The Korean Society of Grassland and Forage Science
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• v.8 no.2
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• pp.92-98
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• 1988

With a purpose of finding out the effects of magnesium and boron enriched organic-compound fertilizer application on the dry matter yield, yield components and changes in the botanical composition on the hilly pasture, a field experiment was arranged with five different treatments as a randomized block desigh and lasted from September, 1984 to the end of growing season in 1986. The results obtained are summarized as follows: 1. As a early plant growth and development, winter hardiness, growth vigour and coverate of grasses at the plots with organic-compound fertilizer application were better comparing to single dressing. 2. Average dry matter yields for two years were shown significantly high due to increasing amount of fertilizer. This trend was same both single and organic-compound fertilizer. And dry matter yields with organic-compound fertilizer application of low (8,693.1 kg/ha) and conventional level (12,758.7 kg/ha) were appeared to increase by 10 and 15% than those of single dressing of Low (7,930.6 kg/ha) and conventional level (11,122.6 kg/ha), respectively. But it was not significant difference. 3. Dry matter yield of grasses was significantly gained by increasing amount of fertilizer. The yield of legumes at the plots with organic-compound fertilizer application the yields of grasses were a litle more increased by 8-14%, and legumes were much more gained by 26-29% than those of the same species groups with single dressing, but it was not significant between the differnet kinds of fertilizer in the same fertilizing level. 4. At the grassland management, the rate of legumes tended to dominate at the plot without fertilization gradually. On the other hand, the botanical compositions and the rates of grasses were much better maintained at the plots with fertilization. But the rates of legumes with organic-compound fertilizer application tended to increase a little more than those of single dressing gradually. 5. All of the soil chemical properties after the experiment were much more improved comparing to before the experiment. But the average contents of soil organic matter and available $P_2O_5$ were slightly higher at the plot with organic-compound fertilization, on the other hand, pH and exchangeable cations tended to a little less than those of single dressing.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.245-250
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• 2004

Farmers typically apply the dressed soil (coarse saprolite) for various reasons in the sloped upland with high altitude in Kangwon province. However, little researches on the impacts of application of dressed soil in uplands were conducted. Therefore, it is necessary to assess soil quality in this area and to study adverse effects on soil and water due to application of dressed soil. Coarse saprolite itself showed signiScantly poor chemical properties, Particularly P and organic matter contents were not enough for crops to grow. With respect to biological qualities such as enzyme activity and microbial population, coarse saprolite itself showed poor qualities. For example, bacterial population in coarse saprolite contains six times or ten times smaller populations. Based on survey at Jawoon-ri in Hongchon-gun, this region is susceptible for soil erosion due to massive amounts of coarse saprolite application, undesirably long slope length, etc. When weestimated soil loss, more than 40% of farming field in this region exceeded $11.2MT\;ha^{-1}\;yr^{-1}$. According to experiment by installing sediment basins. the sediment basin with up-down tillage and application with dressed soil had the highest soil loss and runofT, while the sediment basin with contour tillage and without soil dressing showed the lowest soil erosion and runoff.

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.3
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• pp.37-44
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• 2020

The Project supporting organic fertilizer started in 1999 as a national policy. In farmhouse, over application of mixed organic compound fertilizer(OC) caused salt accumulation in plastic film house soil. To replace inorganic fertilizer with OC fertilizer, this study was investigated the effect of OC application on yield and soil chemical properties for lettuce cultivation in plastic film house. The OC fertilizer was applied at 50(OC50+N50), 100(OC100), and 150(OC150) % level of the basal amount of nitrogen fertilizer in soil testing recommendation. And these were compared to NPK(nitrogen, phosphat, and potash fertilizer) and PK treatment. The yield of lettuce in OC100 was similar to that of NPK treatment. In OC 50, 100 and 150 treatments, pH had a tendency to increase than that of NPK treatment. Nitrate nitrogen(NO₃-N) and electrical conductivity(EC) were similar to NPK treatment. These showed that nutrients from OC fertilizer were less likely to accumulate in soil than NPK. Also, use efficiency of nitrogen in OC100 treatment were similar to NPK treatment. These results suggest that OC application as the basal dressing at the 100% level could be best to prevent a nutrient accumulation of soil and to increase the yield and commercial quality for lettuce.