• Korean Journal of Environmental Agriculture
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• v.16 no.4
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• pp.341-346
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• 1997

The degradation of fungicide oxadixyl in soil amended with manure, chemical fertilizers, heavy metals and detergent was studied. The degradation of oxadixyl in the soil was slow, but became to be fast after the lag phase of about 14 days. The half-life was 10.5 days. The degradation rate was accelerated largely by the amendment of manure. Potassium also promoted the degradation rate but nitrogen and phosphate did not. The heavy metals inhibited the degradation rate, in order of Ni, Cd, Cr, Cu, and Zn. The degradation rate was declined greatly with the addition of synthetic detergent. The microbial biomass and the respiration rate in the soil were increased by the amendment of manure and chemical fertilizers, but decreased by the addition of heavy metals and cleaner. The degradation rate of oxadixyl was positively correlated with the microbial biomass and the respiration rate.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.5
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• pp.492-498
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• 2015

The long-term changes in the soil properties are closely related to the policy direction and the national program for the soil management. In this study, chemical properties of paddy soils in Jeonnam province were investigated at four-year interval since 1999 and the factors affecting change of chemical properties were analyzed in relation to the soil management policies. Chemical fertilizers supplied to Jeonnam province reduced by 57% in 2013 as compared with 1999, and the ratio of Jeonnam province to the national fertilizer supply gradually decreased to 14.1% in 2013 from 17.6% in 1999 due to national policies to reduce use of chemical fertilizers in the 2000s. In the chemical analysis of paddy soils in Jeonnam province, pH value tended to increase gradually within the optimal range. Available phosphate and exchangeable potassium content were always higher than the optimal range and showed no significant difference since 1999. Organic matter, exchangeable calcium and available silicate content were found to be lower than average content in the whole country as well optimal range for rice cultivation in 1999, but were higher than average content in the whole country and optimal range in 2011 because of faster rate of increase in Jeonnam province than the other region since the mid-2000s. The cause of increase in organic matter, exchangeable calcium and available silicate contents is considered to be the increased use of green manure crops and by-products fertilizer as an alternatives for conventional application of chemical fertilizers and soil amendment such as silicate fertilizer for agronomic control of the disease and insect pest in rice cultivation of environmentally-friendly agriculture.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.473-478
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• 2011

A wide diversity of liquid fertilizers and composts produced from the livestock manure in Korea is commonly applied to agricultural lands as an alternative of chemical fertilizers. However, their effects on the crop production and environmental impacts are still vague. The current study was conducted to understand the effects of the pig manure-based liquid fertilizer on the growth of Zea mays L. and soil properties. Four different liquid fertilizers were treated to each cultivated upland plot located in Gyeong-gi province, Korea while no fertilizer (control A) and a chemical fertilizer (control B) were treated to separate plots for comparison. The liquid fertilizer treatment did not make a significant difference in the fresh weight of Zea mays L. compared to the controls. This is probably due to the nutrient residues carried over from the last year fertilization. Electric conductivity (EC) and organic matter contents in soils were increased right after the liquid fertilizer treatments compared to the controls. However, soil pH was maintained as the same as the level of control A. A long-term effect of the continuous treatment of the manure based liquid fertilizer will be carried out in the successive study.

• Journal of Korean Society on Water Environment
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• v.37 no.4
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• pp.306-314
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• 2021

The application of organic fertilizer could be accompanied by potential hazards to soil and humans due to trace metals. Livestock manure compost·liquefied fertilizer is a well-established approach for the stabilization of nutrients and the reduction of pathogens and odors in manures, which can be evaluated as compost·liquefied. In this study, the livestock manure compost·liquefied fertilizers produced at 333 liquid manure public resource centers and liquid fertilizer distribution centers were collected from May to December 2019. The nutrient content (nitrogen, phosphorus, and potassium), physicochemical properties, and heavy metal content were investigated. The livestock manure compost·liquefied fertilizer was measured using a mechanical maturity measurement device. The organic matter, arsenic, cadmium, mercury, lead, chromium, copper, nickel, zinc, E. coli (O157:H7), Salmonella, etc. of the livestock manure compost·liquefied fertilizers were analyzed. The average heavy metal content in the livestock manure compost·liquefied fertilizer was as follows: Cr 2.9 mg/kg (0.2~8.7 mg/kg), Cu 20.4 mg/kg (1.6~74.1 mg/kg), Ni 1.3 mg/kg (0.4~4.2 mg/kg), and Zn 79.8 mg/kg (3.0~340.7 mg/kg). Although large-scale organic fertilizer plants and resources recycling centers produce good organic (liquid) fertilizers with proper components, it is necessary to standardize livestock manure compost·liquefied fertilizer in order to facilitate efforts to turn livestock manure into useful resources.

• Korean Journal of Agricultural Science
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• v.47 no.4
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• pp.1021-1027
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• 2020

The amount of food waste generated in Republic of Korea has been increasing alongside an increasing population and booming economy as such, research on effective treatment and recycling is required. Food waste recycling is complicated by its inferior characteristics such as high levels of water and concern that its continuous application to farmland can lead to salt accumulation and concomitant damage crops. In the present study, therefore, dehydrated food waste powder (FWP), which contains a large amount of organic matter and nutrients, but which may require additional improvements was mixed in various ratios with organic fertilizers and the mixtures were tested for their effects on the growth of the leaf lettuce. A control was set up with inorganic fertilizers alone while a treatment with only FWP was also included. The mixture of FWP and organic fertilizers produced better leaf lettuce growth in all the treatments than the control and FWP. The fresh weight of the leaf lettuce produced with a mixture containing 60% FWP was 50% higher than that of the control. The results from this study indicate, therefore, that FWP mixed with other organic supplements in appropriate amounts positively impacts crop growth and development.

• Korean Journal of Agricultural Science
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• v.49 no.3
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• pp.397-405
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• 2022

Castor oil cake is widely used as a raw material for organic fertilizers (OF) in Korea. Compared to other fertilizer raw materials, it is highly dependent on imports. In terms of replacing raw materials, dehydrated food waste powder (FDP) and castor oil cake have similar nutritional content, and if 30% is replaced, about 20% of the raw material cost can be saved. However, few studies on the effects on crop growth and soil properties when organic fertilizer and dry food waste powder are mixed and applied to the soil have been reported. The effects of an organic fertilizer made by mixing the commercial available organic fertilizer with dehydrated food waste (OF + FDP) on soil properties and the growth of two types of leafy vegetables (lettuce and young radish) were evaluated and compared with the performance of OF. The fresh weights of lettuce and young radish were the highest with OF amendment and stood at 114.3 and 119.0 g·plant^-1, respectively. These were followed by OF + FDP amendment, which produced 103.1 and 109.6 g·plant^-1, respectively. Compared to the control, OF and OF + FDP increased the lettuce fresh weights by about 69% and 52%, respectively, while the fresh weights of the radish were increased by about 223% and 207%, respectively. The soil pH, EC, total carbon content, and organic matter content in OF and OF + FDP increased. The mixture of dehydrated food waste powder and organic fertilizers is expected to improve soil quality and facilitate stable production of crops and contribute to the substitution of imported organic fertilizer raw materials.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.2
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• pp.183-188
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• 1993

This experiment was conducted to investigate the effect of sulfur containing fertilizers on growth, yield and nutritive quality of soybean as affected by lime application at reclaimed soil. Lime application for neutralization requirements showed the effect of increased grain yield about 32% compared to the non application at newly opened land of red and yellow soil. In case of lime application, the sulfur containing fertilizers combined with super phosphate, ammonium sulfate, and gypsum increased the grain yield by 31%, 11%, and 3%, respectively. When lime was not applied, magnesium carbonate application increased the yield by 47%, super phosphate by 22%, and gypsum by 15%. The protein content of grain was higher at lime application than those of non lime application and was increased by the application of sulfur containing fertilizer. But lipid content was not affected by lime or sulfur application. From the above results obtained it was concluded that sulfur fertilizer effect under lime application was significant when combined with super phosphate or ammonium sulfate application. Magnesium carbonate or super phosphate application was the best combination with sulfur-containing fertilizer.

• Journal of Practical Agriculture & Fisheries Research
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• v.8 no.1
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• pp.73-96
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• 2006

Today, producers of ginseng spray prohibited fertilizers or use excessive amount of fertilizers whereas distributers either claim that they are selling domestic ginseng when in fact they are selling imported ginseng, cheat on the age or weight of ginseng, or mix domestic and imported ginseng. In terms of quality in comparison with foreign ginseng, 90% of the people surveyed responded that domestic ginseng is more efficacious. When asked whether they would purchase foreign ginseng products when they become available in the market, only one of the respondents responded that he or she would purchase foreign ginseng whereas 50 respondents or 81% of the total surveyed responded that they wouldn't purchase foreign ginseng. About half of the respondents answered that when Chinese red ginseng, ginseng, or wild ginseng products cultivated with harmful fertilizers become available in the market, they would either reconsider purchasing ginseng products or stop purchasing ginseng products all together. In order to develop the ginseng industry 20 respondents (25%) chose the establishment of the standards, 33 respondents (42%) chose marking the place of origin, 15 respondents (19%) quality improvement, 7 respondents (9%) research on the efficacy, and 4 respondents (5%) said improvement on the storage methods as the important factors of the ginseng industry. Considering the fact that 77% of the respondents selected either the standardization or marking of the place of origin, the consumers seem to be demanding reliability in the distribution of ginseng products. Therefore, those people who work in the industry such as the producers, distributors and others should have a sense of mission to develop ginseng, which is a gift from God, and do their best to produce and distribute ginseng products.

• Safety and Health at Work
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• v.15 no.1
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• pp.110-113
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• 2024

Numerous studies have indicated that organic fertilizers (OFer) might contain heavy metals (HMs) that present health risks to organic farmers (OFar). This study compared the concentrations of six HMs (Zn, Ni, Cd, Cu, Pb, Cr) in the blood of two distinct groups of farmers: 30 OFar from a designated organic area in eastern Taiwan, and 74 conventional farmers (CFar) from neighboring non-organic designated regions. The findings revealed that the OFar exhibited higher levels of Zn (1202.70 ± 188.74 ㎍/L), Cr (0.20 ± 0.09 ㎍/L), and Ni (2.14 ± 1.48 ㎍/L) in their blood compared to the CFar (988.40 ± 163.16 ㎍/L, 0.18 ± 0.15 ㎍/L, and 0.77 ± 1.23 ㎍/L), respectively. The disparities in Zn, Cr, and Ni levels were measured at 214.3 ㎍/L, 0.02 ㎍/L, and 1.37 ㎍/L, respectively. Furthermore, among the OFar, those who utilized green manures (GM) displayed significantly elevated blood levels of Zn (1279.93 ± 156.30 ㎍/L), Cr (0.24 ± 0.11 ㎍/L), and Ni (1.94 ± 1.38 ㎍/L) compared to individuals who exclusively employed chemical fertilizers (CFer) (975.42 ± 165.35 ㎍/L, 0.19 ± 0.16 ㎍/L, and 0.74 ± 1.20 ㎍/L), respectively. The differences in Zn, Cr, and Ni levels were measured at 304.51 ㎍/L, 0.05 ㎍/L, and 1.20 ㎍/L, respectively. As a result, OFar should be careful in choosing OFer and avoid those that may have heavy metal contamination.

• Korean Journal of Soil Science and Fertilizer
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• v.15 no.1
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• pp.2-15
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• 1982

In this report, a total domestic demand for major commercial fertilizer for crop production in Korea up to 1996 was estimated. The agricultural products and area for demand for both 1982 and 1986 was quoted from the estimate of the 5th Five-year Economic plan. And the demands estimated for 1991 and 1996 reflected possible changes of diet from cereal to meat and their indirect effects on the increase of cereal consumption. As the advanced countries followed, consequently, the demands for soybean, corn and other feed grains were expected to be increased as well as the land for growing those crops. 1. Total annual demands for nitrogen, phosphorus and potassium fertilizers were estimated 1,050,000M/T, 1,110,000M/T, 1,280,000M/T and 1,010,000M/T for the year 1982, 1986, 1991, and 1996 respectively. 2. It was assumed that there would be difficulties in self-sufficiency of grains at the cost of the maximum utilization of land and fertilizers in 1996. 3. It was clear that the increase of the productivity per unit area is possible by improving the conditions of arable land which could resulted a self-sufficiency of food in Korea. As a consequence, the demand for fertilizers at that time would exceed the level of estimates. 4. The recent decrease in demand for commercial fertilizers (currently estimated 850,000M/T) was due to an inadequate application of fertilizers for respective crop reqirement. This inadequacy should be checked and encouraged the consumptions of fertilizers to be increased by supporting the price of grain.