• Korean Journal of Soil Science and Fertilizer
• /
• v.49 no.6
• /
• pp.760-767
• /
• 2016

Food waste (FW) has been recognized as a critical problem in Korea and many research was conducted to efficiently utilize or treat FW. Main purpose of this research was to evaluate a feasibility for producing fermented organic fertilizer with vegetable waste (VW). Three different organic materials (saw dust, coco peat, and waste mushroom media) were mixed with VW at the rate of 30, 40, 50% respectively. Total days of composting experiment were 35 days and each sub samples were collected at every 5 days from starting of composting. Result showed that inner temperature of composting was increased to $60{\pm}4^{\circ}C$ within 5~10 days depending on varied organic materials and mixing ratio. Among different treatment, the highest increase of inner temperature was observed when 30% of saw dust was mixed with VW. After finishing composting experiment, maturity of each compost was evaluated with solvita and germination test. Maturity index (MI) of each treatment was ranged between 5~7 indicating that manufactured fertilizer was curing or finished stage. Calculated germination index (GI) was at the range of 57.83~101.16 depending on organic materials and mixing ratio. Both MI and GI showed that manufactured fertilizer was met for fertilizer criteria while control (VW only) was not adequate for composting. Overall, VW can be utilized for making organic fertilizer mixing with saw dust, coco peat and more research should be conducted to make high quality of organic fertilizer with vegetable waste.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2000.11b
• /
• pp.430-437
• /
• 2000

Fertilizer impaction mechanism was simulated using a commercial program RecurDyn$^{(R)}$ a dynamic program that could handle contact problems. Even if there had been numerous papers on modeling of fertilizer applicator, the performance predictions were not satisfactory due to simplification in modeling. The most significant simplification was assumption of fertilizer particles as a solid particle. The assumption would eliminate rotation of fertilizer particles during the impaction mechanism. However, impaction of rotating body would be different from that of a solid particle. This paper introduced how the impaction was modeled using RecurDyn$^{(R)}$. In order to simulate, restitution coefficient and contact time was measured. A stiffness coefficient and a damping coefficient of a fertilizer was theoretically estimated using the measured data. Validity of the simulation result was not proved yet, but judged to be promising.ged to be promising.ing.

• Clean Technology
• /
• v.22 no.1
• /
• pp.29-34
• /
• 2016

Field cultivation of corn and microbial cell viability tests using Pseudomonas putida K-5 were performed to assess the toxic effect of kelp seaweed biochar (KBC) and fir wood biochar (FBC) produced by pyrolysis. After 63 days growth, FBC increased corn growth by 4.9% without fertilizer and by 7.6% with fertilizer, while KBC decreased it by 20.2% without fertilizer and by 27.9% with fertilizer. Physico-chemical characterization of the biochars such as ICP, CHON, and proximate analyses showed that KBC contained large amount of metals and ashes which could be responsible for its inhibition to corn growth. Upon exposure of K-5 cells for 1 h to biochar extracts, the cell viability in KBC extracts was 48.2% and quite lower than that (78.6%) in FBC. Washed KBC biochar with water at 1:10 w/v % increased the cell viability to 54.0%. The results indicated that seaweed biochar may be careful to be used for plant growing additives due to its high concentrations of metals and ashes. This toxic effect could be reduced by proper washing method with water.

• Korean Journal of Soil Science and Fertilizer
• /
• v.42 no.spc
• /
• pp.1-3
• /
• 2009

Silver nanoparticles have been used in agricultural practice because of their biocide effect. However, limited information is available for the effect of silver nanoparticles on soil quality. Therefore, the main purpose of this study was to evaluate effect of silver nanoparticle application on soil especially when fertilizer is applied. To simulate potassium fertilizer, potassium chloride was mixed with silver nanoparticles in soil. Concentration of silver and chloride was measured and result showed that concentration of both compounds was decreased at the range of $3.4mg\;kg^{-1}$ and 78-84% respectively after treatment. In addition, analysis of microbial population after treatment showed that microbial population was increased when silver nanoparticles and KCl were mixed. Those results indicated that application of fertilizer has impact on biocide effect of silver nanoparticles in soil.

• Applied Biological Chemistry
• /
• v.44 no.2
• /
• pp.129-132
• /
• 2001

• Asian Journal of Turfgrass Science
• /
• v.18 no.2
• /
• pp.71-76
• /
• 2004

Solid typed organic fertilizer from cattle manure may Increase plant root growth with the residual effect on soil fertility if it was applied directly into root system. It may also increase labour efficiency by simplifying the work process of manure application to soil. This research was carried out from May to October 1999 to study the fertility prolongation effects of bar typed organic fertilizer from poultry manure by analysing plant growth model compare with those of the chemical fertilizer or powder typed manure. The results showed that the bar typed organic fertilizer increased growth rates of shoot and root system with extending the effect of its fertility by slow releasing on pepper plant. Especially, solidifying organic manure into the bar type made possible the application of cattle manure under plastic mulching. And it also has benefits on simplifying the application process of the fertilization and effect on an extending soil fertility.

• Journal of Korean Society on Water Environment
• /
• v.25 no.5
• /
• pp.727-734
• /
• 2009

This study was carried out to evaluate the high rate biological reactor such as lab scale reactor before the application in site, and to get the basic data for possibility using liquid fertilizer with the effluent from biological reactor when the centrifugal machine was applied. The total volume of this reactor in 6 L, in composted of anoxic reactor (2 L), aerobic reactor (2 L), and nitification reactor (2 L). BOD removal efficiency rates when centrifugal machine was applied after effluent from biological reactor are over than 95%. This biological reactor was required post process to satisfy the effluent standards, and was need centrifugal machine to control the washout of microbes in the reactor. T-N removal efficiency rate in HRT 24 hr with centrifugation is 80.0%, and it is desirable to operate less than $1.3kgN/m^3{\cdot}d$ for 70% of T-N removal efficiency rate. T-P removal efficiency rate in HRT 24 hr is 68.2%, and become higher 71.3% after centrifugation. Considering in the 28.6% T-N removal efficiency rate, the nitrogen contents of the effluent from reactor is 0.34% to satisfy the liquid fertilizer.

• Korean Journal of Soil Science and Fertilizer
• /
• v.50 no.6
• /
• pp.588-597
• /
• 2017

Food waste has been recognized as a critical problem in Korea and many research was conducted to efficiently reutilize or treat food waste. Main purpose of this research was to evaluate a feasibility for producing fermented organic fertilizer with mixture of earthworm cast (EC). Four different treatments were mixed with food waste and EC at the rate of 0, 10, 20, and 30%, respectively. Total days of composting experiment were 84 days and each sub samples were collected at every 7 days from starting of composting. Results showed that inner temperature in composting was increased to $70{\pm}4^{\circ}C$ within 5~10 days depending on mixing ratio of EC. Among different treatment, the highest increase of inner temperature was observed in treatment mixed with food waste and EC 30%. After finishing composting experiment, maturity was evaluated with solvita and germination test. Maturity index (MI) of each treatment was ranged between 5~7 indicating that manufactured fertilizer was curing or finished stage. Calculated germination index (GI) was at the range of 104~116 depending on mixing ratio of EC. Both MI and GI showed that manufactured fertilizer was suitable for fertilizer criteria while control (FW only) was not adequate for composting. Overall, earthworm cast can be utilized for improving compost maturity by mixing with food waste and more research should be conducted to make high quality of food waste compost with earthworm cast in agricultural fields.

• BMB Reports
• /
• v.56 no.2
• /
• pp.56-64
• /
• 2023

Nitrogen (N) is an essential macronutrient required for plant growth and crop production. However, N in soil is usually insufficient for plant growth. Thus, chemical N fertilizer has been extensively used to increase crop production. Due to negative effects of N rich fertilizer on the environment, improving N usage has been a major issue in the field of plant science to achieve sustainable production of crops. For that reason, many efforts have been made to elucidate how plants regulate N uptake and utilization according to their surrounding habitat over the last 30 years. Here, we provide recent advances focusing on regulation of N uptake, allocation of N by N transporting system, and signaling pathway controlling N responses in plants.

• Korean Journal of Environmental Agriculture
• /
• v.36 no.4
• /
• pp.223-229
• /
• 2017

BACKGROUND: Tillage systems and fertilization play an important role in crop growth and soil improvement. This study was conducted to determine the effects of tillage and fertilization on the microbial biomass C and dehydrogenase activity of soils in a field under cultivation of soybean. METHODS AND RESULTS: An experimental plot, located in the temperate climate zone, was composed of two main sectors that were no-tillage (NT) and conventional tillage (CT), and they were subdivided into four plots, respectively, in accordance with types of fertilizers (non fertilizer, chemical fertilizer, hairy vetch, and liquid pig manure). Microbial biomass C and dehydrogenase activity were evaluated from May to July in 2016. The microbial biomass C and dehydrogenase activity of NT soils were significantly higher than those of CT in all fertilizer treatments, and they were further increased in hairy vetch treatment than the other fertilizer treatments in both NT and CT. The dehydrogenase activity was closely related to microbial biomass C. CONCLUSION: It is concluded that application of green manure combined with no-tillage can provide viable management practices for enhancing microbial properties of soil.