• Journal of the Korea Organic Resources Recycling Association
• /
• v.31 no.3
• /
• pp.43-53
• /
• 2023

This batch experiment evaluated the impacts of major plant nutrient releases by applying the modified Hyperbola model on the leachates and N₂O emissions from incorporated rice hull biochar with organic fertilizer materials. The treatments consisted of the control as incorporated with organic fertilizer materials, the incorporated rice hull biochar with organic fertilizer materials, and the incorporated plasma-activated rice hull biochar with organic fertilizer materials under redox conditions. The results indicated that the maximum release amount of NH₄-N was 3486.3 mg L^-1 in the control, and their reduction rates of NH₄-N, NO₃-N, PO₄-P, and K were 8.0%, 17.5% 44.3.0% and 8.7%, respectively, relative to the control. In the control, the highest soluble amount of PO₄-P was 681.0 mg L^-1. The estimations for accumulated NH₄-N, NO₃-N, PO₄-P, and K-releases in all the treatments were significantly (p<0.01) fitted with a modified Hyperbola model. For greenhouse gas emissions, the lowest cumulative N₂O was 340.4 mg kg^-1 in the soil incorporated with plasma-activated rice hull biochar, and the reduction rates were 27.8% and 86.4% in the rice hull biochar and plasma-activated rice hull biochar treatments, respectively, compared to the control. Therefore, it concluded that the incorporated rice hull biochar can be especially useful for controlling PO₄-P release and N₂O emissions for bio-fertilizer applications.

• Korean Journal of Environmental Biology
• /
• v.34 no.3
• /
• pp.169-176
• /
• 2016

Although chemical fertilizers have a quick effect and broad applicability to agricultural fields, they have caused many problems like increasing soil acidity or decreasing soil organic matters. Environmental-friendly agriculture has been attempted in various ways such as organic agriculture, natural farming, low input and sustainable agriculture. The common interest of all environmental-friendly systems is to decrease burden to agricultural environment by low input of agricultural labor and materials. This study was conducted to estimate overwintering capacity and genetic distance among Chinese Milk Vetch (Astragalus sinicus, CMV) collections based on morphological characteristics and AFLP (Amplified fragment length polymorphism) analysis. Furthermore, the effect of CMV as green manure was observed in mix-cultured paddy fields with rice, sesame and sweet-potato. An another objective of this study was also to compare the pattern of weed occurrence in paddy fields with or without CMV and different rice transplanting times. The CMV collected from Paju district in central region of Korea was successively occurring through self-reseeding without artificial management. However, there was no noticeable difference in growth habit between Paju native CMV and introduced CMV from China which is currently used in farm fields. On the basis of multi-dimensional scaling and tree analyses, there are no significant difference of agricultural growth characteristics among Paju and chinese collections only excepting leaf angle and root length. The flowering time of Gurye collection was fast for 1 week as compared to other collections. AFLP that was commonly used for plant classfication, was applied to exam the genetic variation of CMV collections. Total 579 PCR products and 336 polymorphic fragments were generated using 8 primer pairs.

• Applied Chemistry for Engineering
• /
• v.28 no.5
• /
• pp.501-505
• /
• 2017

Due to the rapid urbanization and increased population, there is an increase in airtight nature of buildings which causes serious indoor air pollution. Among several indoor air pollutants, volatile organic compounds (VOCs) emitted from paint are of major concern. Therefore, there is an urge for the development of environmental friendly paint products. In this wok, a natural wall paint (NWP) was prepared by utilizing a natural clay material "sericite" as a main component. A small chamber test was carried out to identify the toxic substances release from NWP and the results were compared with two eco-friendly commercial paints. The total VOCs were detected in trace level inside the test chamber and their concentrations were below the recommended indoor air quality standards. Toluene was not detected for NWP, whereas formaldehyde was observed in trace level. The toxicity index results were compared with two commercial paints and found that NWP exhibited less harmful gas emission. Based on certification rating of building materials, NWP can be classified as the first grade of building materials. Due to the above advantages, the use of sericite as a major component in NWP will be a useful technique to maintain the indoor air quality.

• Research in Plant Disease
• /
• v.27 no.3
• /
• pp.91-98
• /
• 2021

The current social demand for organic, sustainable, and eco-friendly approaches for farming, while ensuring the health and productivity of crops is increasing rapidly. Biocontrol agents are applied to crops to ensure biological control of plant pathogens. Research on the biological control of white root rot disease caused by a soil-borne pathogen, Rosellinia necatrix, is limited in pears compared to that in apple and avocado. This pathogenic fungus has an extensive host range, and symptoms of this disease include rotting of roots, yellowing and falling of leaves, wilting, and finally tree death. The severity of the disease caused by R. necatrix, makes it the most harmful fungal pathogen infecting the economical fruit tree species, such as pears, and is one of the main limiting factors in pear farming, with devastating effects on plant health and yield. In addition to agronomic and cultural practices, growers use chemical treatments to control the disease. However, rising public concern about environmental pollution and harmful effects of chemicals in humans and animals has facilitated the search for novel and environmentally friendly disease control methods. This review will briefly summarize the current status of biocontrol agents, ecofriendly methods, and possible approaches to control disease in pear orchards.

• Journal of Adhesion and Interface
• /
• v.21 no.4
• /
• pp.156-161
• /
• 2020

Waterborne pressure sensitive adhesives (PSA) has been received much attentions from both academia and industries as an environmental friendly-technology because it can significantly reduce use of hazardous organic volatile solvents. However, in the process of the mass production of waterborne PSAs, hazardous phenol type amphiphilic compounds have essentially been used as surfactants for the emulsion polymerization. For the reason, tremendous research efforts have been made to develop environment-friendly organic surfactant which can replace the phenol type surfactants. In this study, we verify the potential of a new class of surfactants based on the styrenated phenol derivatives as an alternative to the phenol type surfactants.

• Research in Plant Disease
• /
• v.14 no.3
• /
• pp.182-186
• /
• 2008

Recently organic farming practice of rice has been emerged in Korea, but one of the major limiting factor is the no effective environmental-friendly agro-materials to control major plant diseases. Bordeaux mixture has been used effectively as a preventive agro-chemical. The aim of this study was to investigate efficacy of Bordeanux mixture on control of rice blast caused by Magnaporthe grisea which is one of the disruptive rice diseases in world-wide. In greenhouse experiment, pre-treatment of 6-6 type of Bordeaux mixture before inoculation of spore suspension of M. grasea showed 71 % of control value. In field experiment, preventive applications of 4-8 and 6-6 types of Bordeaux mixture showed over 71 % of the control value. Chemical injury on rice leaves were not found in the application concentrations of all types of Bordeaux mixture, but observed in applications of Bordeaux mixtures between 30 and 100 diluted concentrations. This results indicate Bordeaux mixture can be used as an effective environmental-friendly agro-chemical to control rice blast disease in the field.

• Resources Recycling
• /
• v.20 no.4
• /
• pp.65-70
• /
• 2011

Environmental friendly leaching process for the recovery of cobalt and lithium from the $LiCoO_2$ was investigated by organic acids as a leaching reagent. The experimental parameters, such as organic acid type, concentrations of leachant and hydrogen peroxide, reaction time and temperature as well as the pulp density were tested to obtain the most effective conditions for the leaching of cobalt and lithium. The results showed that the latic acid was the most effective leaching reagent for cobalt and lithium among the organic acids and was reached about 99.9% of leaching percentage respectively. With the increase of the concentration of citric acid, hydrogen peroxide and temperature, the leaching rate of cobalt and lithium increased. But the increase of pulp density decreased the leaching rate of cobalt and lithium.

• Korean Journal of Organic Agriculture
• /
• v.30 no.3
• /
• pp.409-422
• /
• 2022

Southern blight caused by Sclerotium rolfsii is a serious soilborne disease in economically important crops including pepper. In this study, we conducted a selection of antagonistic bacterial strains and organic materials to biologically control the disease. Out of 39 strains isolated from soils at Jinju in Korea, strain JJ2-01 showed the highest mycelial growth inhibition; garlic oil among various organic materials significantly reduced disease incidence and severity. When a combination of strain JJ2-01 and garlic oil, or each was drenched into the pepper plants, combined treatment and garlic oil significantly suppressed the disease development, however, acid phosphatase activity in garlic oil-treated plants decreased. In the case of combined treatment, the soil activities did not affect by treatment, while soil urease activity was significantly increased by the combined treatment. Therefore, given soil quality and health for sustainable agriculture, the combination of strain JJ2-01 and garlic acid was an effective application for environmental-friendly control of Southern blight in pepper plants.

• Journal of Distribution Science
• /
• v.13 no.11
• /
• pp.59-67
• /
• 2015

Purpose - The number of consumers adopting a lifestyle of health and sustainability has recently increased with the rise of trends in healthy living. The size of the organic agricultural product market has also increased given that these consumers prefer consuming environmentally friendly products that promote family health. However, awareness of organic agricultural products remains insufficient because of the characteristics of the Korean organic agriculture system, which only focuses on food safety inspection. The object of this research is to suggest a policy approach to increase understanding and to expand the purchasing of organic agricultural products by analyzing the influence of customer recognition of such products on their willingness to repurchase. Research design, data, and methodology - This study used binomial logistic regression analysis with the aim of explaining the effects of consumers' socio-demographic characteristics, their awareness of the equivalence arrangement for organic food and of the abolishment of low-pesticide agricultural product certification, and their viewing of negative broadcasts about organic agricultural products on their repurchase intention of such products. A questionnaire survey was conducted with 655 respondents who were in their 20s, lived either in Seoul or in its metropolitan area, and had purchased organic agricultural products. Result - From the results of the analysis, the majority of the respondents recognized organic agricultural products, but they found their prices to be expensive. The majority of the respondents were also aware of the certification system and the reliability of organic agricultural products. However, the results indicate that efforts need to be made to recover consumer trust as many respondents stated that their trust levels in these products were low. In general, those purchasing organic agricultural products were satisfied, but those answering "very satisfied" were not in the majority. Binomial logistic regression analysis results revealed that repurchase intention decreased as consumers viewed a greater number of negative broadcasts about these products. On the other hand, repurchase intention increased as they became more aware of the abolishment of low-pesticide certification. Repurchase intention also increased as income increased, as the number of family members decreased, and when a consumer was a member of a consumer organization. In addition, the older the consumers were who watched the TV programs, the smaller the number of family members that were aware of the abolishment of low-pesticide agricultural product certification and, the higher the income of the consumers aware of organic equivalence arrangement, the greater their repurchase intention. Conclusion - External stimuli, such as negative TV programs on organic agricultural products and the abolishment of the low-pesticide agricultural product certification, relevant social issues and systems, influence consumer repurchase intention. To that end, positive environmental and ecological broadcasting about organic agricultural products would contribute to an increase in purchasing. Additionally, this could be used for promotion and marketing plans as the results indicate that trust in organic agricultural products would cause a positive repurchasing effect.

• Korean Journal of Organic Agriculture
• /
• v.22 no.1
• /
• pp.155-166
• /
• 2014

Organic forage production system is one of the most important aspects in organic livestock production. Animals in the organic farming system are also essential for manure to be used for organic forage production. Both organic forage and animals are essential to maintain the cycle of organic agriculture system. In this paper we introduce the organic forage production system in Korea. Summer and winter crops are getting popular in Korea because of their high forage yield and cultivation in double cropping systems. Common cropping system for forage production in Korea is the double cropping system with legume and grass mixture. Forage sorghum and sudangrass are the most popular ones of annual summer forage corps because of their high production with low cost in the double cropping systems. In the mixture of forage crops, inter cropping is more suitable in the corn and sorghum cropping system because of high lodging resistance and forage yield, and low weed population. Forage sorghum and sudangrass are difficult to preserve as direct-cut silage due to the fact that its high moisture content causes excessive fermentation during ensiling. Corn grain addition to sorghum silage could be recommended as the most effective treatment for increasing quality and reducing production cost. It is recommended that corn grain could be added up to 10% of total amount of silage. And agriculture by-products also can be added at the time of ensiling to minimize losses of effluent and have the additional advantage of increasing quality. Agriculture by-products as silage supplements increased DM content and quality, and decreased the production cost of sorghum silage. Field pre-wilting treatment of forage crops also increased DM content and quality of the silage. Wilting sorghum${\times}$sudangrass hybrid before ensiling was the effective method for reducing effluent and increasing pH and forage quality more than direct cut silage. Optimum prewilting period of sudangrass silage was 1 or 2 days. In organic forage, the most important factor is the enhancement of organic forage sufficiency in relation to the environmental-friendly and organic livestock. Consequently, there are many possibilities for animal production and organic forage production in Korea. No forages no cattle concept should be emphasized in organic farming system.