• Korean Journal of Agricultural Science
• /
• v.46 no.1
• /
• pp.93-102
• /
• 2019

The materials of artificial soils in the production process of container seedlings have a great influence on plant growth. Peat moss, vermiculite, and perlite have been used as major components of artificial soils for many years; however, they could decrease carbon fixation carried out by the soil and cause environmental problems such as a change in the water quality. Thus, environmental friendly materials to replace them must be developed. The purpose of this study was to verify the optimum additive materials of artificial soils and their mixed ratios for the growth and seedling quality index (SQI) of Quercus serrata. Rice husk, mushroom sawdust, and pine bark were each used as an additive material and mixed into the growth medium at 10% and 20% of the total volume. There was no significant difference in the height growth of Q. serrata. The 20% mushroom sawdust decreased the root collar diameter by 23.4% compared to the control. The total dry weight was highest with the 10% rice husk and was significantly lower by 10.3% for the 20% mushroom sawdust compared to the control. Additionally, the SQI for all the treatments showed no tendency to increase compared with the control. Thus, this study showed the possibility of recycling biomaterials from agriculture and forest for seedling production. This method could reduce environmental problems and help eco-friendly nurseries to achieve a carbon negative impact by the recycling of by-products.

• Journal of Distribution Science
• /
• v.13 no.6
• /
• pp.97-104
• /
• 2015

Purpose - The distribution of agricultural products is changing due to recent shifts in environmental free trade. Specifically, the competitiveness of domestic agricultural products has weakened as a result of the Korea-China Financial Trade Agreement. Agricultural producers are faced with increasing difficulties and organized production centers are growing in importance daily. To overcome this crisis, agricultural producer organizations are vying for environment-friendly agricultural certifications, Good Agriculture Practices (GAP) and Hazard Analysis and Critical Control Point (HACCP). In particular, as consumer demand for higher safety grows, farmers are increasing their certification rates. Therefore, this certification system is expected to help strengthen the competitiveness of agricultural producer organizations. Research design/data/methodology - Organized production centers are classified by certification. A survey was conducted with 91 organizations using factor analysis and logistic regression analysis for the examination. The factor analysis results are as follows. Raw material procurement, education·specialization, marketing, joint business, organizing ability, business management, effectiveness, certification, and larger organizations were classified as the nine types of factors. These factors affect the organized production centers and are used in the logistic regression analysis. The purpose of such research and analysis is to suggest a direction for future production center policies. Results - The basic statistical results are as follows: analysis of the producer organizations of 91 sites, average number of members per site of 1,624, and average sales of 25,961 million won. Additionally, the average income per farmer is 175 million won, and the pooling system rate is 53.5%. The factor analysis results are as follows. Factor 1 consists of contract cultivation, ongoing shipment, selection subdivision, traceability, and major retailer management. Factor 2 consists of manual cultivation, specialty selection, education program, and R&D. Factor 3 consists of advertising, various dealers, various sales strategies, and a unified sales counter. Factor 4 consists of agricultural materials co-purchase, policy support, co-shipment, and incentives. Factor 5 consists of the co-selection and pooling system. Factor 6 consists of co-branding and operating by the organization's article. Factor 7 consists of the buy-sell ratio and rate of operation of the agriculture promotion center. Factor 8 consists of bargaining power in volume and participation rate of farmer certification. Factor 9 consists of increasing new subscribers. The logistic regression analysis results are as follows. Considering the results by type of certification, the environment-friendly agricultural certification type and the GAP certification type have a (+) influence. GAP and HACCP certification types affecting the education·specialization factor have a (+) influence. Considering the results for each type of certification, the environment-friendly agricultural certification types on the effectiveness factor have (-) influence; the HACCP certification types on the organizing ability and effectiveness factor have a (-) influence. Conclusions - Agricultural producer organizations should develop plans as follows: The organizations need to secure education for agricultural production; increase the pooling system ratio for sustainable organizational development; and, finally, expand the number of agricultural producer organizations.

• Economic and Environmental Geology
• /
• v.45 no.2
• /
• pp.137-144
• /
• 2012

Soil pan typically presents the problems in soil water movement or in aeration which is not appropriate for a plant root growth, In this study physico-chemical characteristics of soils and micromorphological characteristic of clay accumulated zone were investigated to identify redox characteristic and evolution of a fragipan of Gangreung series commonly developed in coastal terraces. Gangreung series is classified as Aquic Fragiudalfs according to the USDA soil taxonomy. It is known that sedimentary ocean floor results in soil pan having parallel liner soil structure due to landscape evolution around 200 to 250 million years ago. it is considered that illite, kaolinite, and vermiculite are major clay minerals contained in a fragipan of Gangreung series. Mixed gray and reddish brown colored band around soil pores was found and would be the redoxmorphic features of fragipan. It is possibly due to accumulated illuvial clay and ferriargillans in soil pores and aggregates in reducing conditions eluding ferrous material. Therefore, mixed colored band around pores in soils of Gangreung series would be developed from the eluted ferrous materials which were accumulated in fragipan during the emerged land formation.

• Korean Journal of Environmental Biology
• /
• v.39 no.3
• /
• pp.329-335
• /
• 2021

Chinese cabbage fields have been damaged by cyst nematodes in highland of Gangwon province in Korea since the year 2011, and clover cyst nematode (CCN) is one of the most problematic cyst nematodes in the crop. To investigate the plant resources for breeding new Chinese cabbage cultivar, which is resistant to CCN, screening for resistance of fifty-seven Brassicaceae plant resources to CCN was conducted. Among the plant resources, fifty-four plant resources (Brassica rapa subsp. pekinensis, B. rapa, Brassica sp., B. juncea, B. carinata, B. rapa subsp. nipposinica, B. rapa subsp. narinosa, B. rapa var. perviridis, B. rapa var. perviridis, B. napus var. napobrassica, and Eruca sativa) were very susceptible to CCN and the number of females on roots was more than 300. Two plant resources (B. carinata and B. tournefortii) with more than 100 females on roots were susceptible to CCN. However, African mustard (B. tournefortii, Korean Genebank accession no. IT218058) was resistant to CCN because of the small number of females (4±1.8) on roots. This study showed that African mustard (IT218058) was valuable as a breeding material for Chinese cabbage, which is resistant to CCN.

• Journal of Korean Elementary Science Education
• /
• v.30 no.3
• /
• pp.271-281
• /
• 2011

The environmental education is based on the assumption that accurate knowledge and attitude could be linked to real action, but those have no effect on changing the behavior. To effect the change in behavior, we need to consider the reflective thinking which can make people change their behavior. The strategies to accelerate the reflective thinking are five steps of the reflective thinking process and the interaction through the discussion of students. And also, it is more proper if the contents are based on the real experiences of the students. Thus, this study tried to know whether the improvement of reflective thinking was able to affect to the environmental behavior. The environment education program was applied to the 60 elementary school 6th grade students in Gyeonggi-do and the survey methods were presented in the general experimental curriculum. To study 6th subjects (energy, harmful chemical material, heavy metal and agricultural chemicals, food additive, environmental friendly consumption, and recycle) was developed. This study shows the effect of the program on the environment knowledge, the environment behavior, the level of reflective-thinking and communication ability.

• Korean Journal of Environmental Agriculture
• /
• v.30 no.3
• /
• pp.234-242
• /
• 2011

BACKGROUND: Cultivation of winter cover crops is strongly recommended to increase land utilization efficiency, animal feeding material self-production, and to improve soil and environmental quality. METHODS AND RESULTS: Four major winter crops (barley, Chinese milk vetch, hairy vetch, and rye) having different C/N ratio were seeded in silt loam paddy soil in the November 2007 and the aboveground biomass was harvested on the late May 2008 to evaluate its effectiveness as green manure, and root biomass distribution was characterized at the different depth (0-60 cm) to study its effect on physical properties and carbon sequestration in soil. During this experiment, the naturally growing weed in the rice paddy soil in Korea, short awn foxtail (Alopecurus aequalis Sobol), was considered as control treatment. Above-ground biomass of all cover crops selected was significantly higher than that of the control treatment (2.8 Mg/ha). Comparatively higher above-ground biomass productivity of rye and barley (15.8 and 13.5 Mg/ha, respectively) suggested that these cover crops possibly had the highest potential as a green manure and animal feeding material. Root biomass production of different cover crops followed the same trend as that for their above ground biomass. Rye (Secale cereal) might have the highest potential for soil C accumulation (7893 C kg/ha) by root biomass development, and then followed by barley (6985 C kg/ha), hairy vetch (6467 C kg/ha), Chinese milk vetch (6671 C kg/ha), and control (5791 C kg/ha). CONCLUSION(s): Cover crops like rye and barley having high biomass productivity might be the most effective winter cover crops to increase organic carbon distribution in different soil aggregates which might be beneficial to improve soil structure, aeration etc. and C sequestration.

• Journal of Animal Environmental Science
• /
• v.18 no.sup
• /
• pp.65-72
• /
• 2012

This study was conducted to investigate the effects of bedding thickness of sawdust on feed intake, blood metabolites concentration and environmental condition of cowshed floor for Hanwoo. Feed intake was increased at thicker bedding groups (15 or 20cm), compared with thinner bedding group (10cm). The thicker bedding had a positive effect on concentration of serum total protein, high density lipoprotein (HDL)-cholesterol, low density lipoprotein (LDL)-cholesterol and ${\gamma}$-glutamyltransferase (GGT). Moisture content and the number of E. Coli in the bedding material were remarkably lower in 15 and 20 cm groups, compared with 10 cm group. Based on the data obtained in this study, approximately 20 cm bedding thickness or at least over 15 cm would be maintained to improve the health condition of Hanwoo and hence to enhance the productivity.

• Korean Journal of Environmental Agriculture
• /
• v.33 no.4
• /
• pp.395-402
• /
• 2014

BACKGROUND: Azadirachta indica Extract(AIE) containing azadirachtin as active ingredient have been used worldwide as environment-friendly organic material having pest control properties. However, the extracts prepared with different solvent and from different plant site is very diverse and have different toxicity. METHODS AND RESULTS: In this study, the four week repeated oral dose toxicity test of aqueous AIE in Sprague-Dawley rats was carried out to investigate the toxic effect of liver, main toxicity target organ of AIE. The male and female rats were divided into 4 groups, respectively; control(0 g/Kg bw), low-dose group(0.5 g/Kg bw), middle-dose(1.0 g/Kg bw) and high-dose group(2.0 g/Kg bw). As a results, relative liver weight increased with dose-dependent of AIE(p<0.05). Serum LDH in all AIE-treated groups were significantly lower than the control in male rats(p<0.05). However, serum GOT and GPT were significantly increased in all male AIE-treated groups in male rats(p<0.05) and, in particular, increase of serum GPT in dose-dependent manner raise the possibility of liver damage. Even through serum GLU was increased significantly in high-dose group in male rats compared to control, there were no significant differences of urinary GLU among all groups(p<0.05). In addition, histopathological examination of the liver did not reveal any lesions in all AIE-treated groups. CONCLUSION: In conclusion, 4 weeks of the repeated oral administration of AIE 2.0 g/Kg to rats has resulted no toxic response in liver. Therefore, AIE was no indicated to have any toxic effect in the SD rats, when it was orally administrated below the dosage 2.0 g/Kg/day for 4weeks.

• Korean Journal of Soil Science and Fertilizer
• /
• v.38 no.2
• /
• pp.108-117
• /
• 2005

Pharmaceutical byproduct sludge and cosmetic industry wastewater sludge can be used as a raw material of compost. Effects of three types of pharmaceutical byproduct sludge and one type of cosmetic industry wastewater sludge on soil properties and red pepper growth were investigated in a field based concrete pot ($2{\times}2m$). These sludges and pig manure ($5Mg\;ha^{-1}$, dry basis) were incorporated into the upper of loam soil 30 days prior to transplanting red pepper. Changes in soil properties and contents of heavy metals and toxic organic compounds in soil and plant were measured. And also plant growth measurement and bioassay of soil phytotoxicity were included. Contents of heavy metals were increased in the soils treated with the sludges. Plant growth in the sludge treatments were mostly inferior to that of NPK treatment, especially in early stage. Content of N in plant was lower in all sludge treatments at early and middle growth stages, and it was especially caused by characteristics and concentration of nitrogen and organic matter of sludges. Total yield of red pepper was highest in the NPK treatment and followed by pharmaceutical sludge 3, pig manure, pharmaceutical sludge 1, and pharmaceutical sludge 2, and the yield of cosmetic sludge treatment was considerably lower than others. HEM and PAHs contents in soil of cosmetic sludge treatment were $4.80mg\;kg^{-1}$ and $2,263.2{\mu}g\;kg^{-1}$, respectively. Root elongation of lettuce exposed to the water extract of soil treated with cosmetic sludge was about 20% of that found in the test with soil extract of non fertilization treatment. At present, raw materials of compost were authorized according to the contents of organic matter, heavy metals and product processing. Toxic organic compounds analysis and bioassay would be helpful for authorization and assessment of suitability of raw materials of compost.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.50 no.4
• /
• pp.281-285
• /
• 2005

Pod dehiscence (PD), defined as the opening of pods along both the dorsal and ventral sutures, causes the seed to shatter in the field before harvesting and results in loss of seed yields. However, breeding for resistance to PD is difficult due to the complicated genetic behavior and environmental interaction. The objective of the present research was to analyze the genetic behavior of PD for improving the breeding efficiency of resistance to PD in soybean. PD after oven-drying the sampled pod at $40^{\circ}C$ for 24 hours was the most reliable to predict the degree of PD tested in the field. Keunolkong, a dehiscent parent, was crossed with non-dehiscent parents, Sinpaldalkong and Iksan 10. Using their $F_1\;and\;F_2$ seeds, PD was measured after oven drying the pod at $40^{\circ}C$ for 24 hours. The gene conferring PD behaved in different manners depending on the genetic populations. In the Keunolkong$\times$Sinpaldalkong population, PD seemed to be governed by single major recessive gene and minor genes, while several genes were probably involved in the resistance to pod dehiscence in the Keunolkong$\times$Iksan 10 population. Heritability for PD estimated in F2 population showed over $90\%$ in the two populations. High heritability of PD indicated that selection for resistance to PD should be effective in a breeding program. In addition, genetic mapping of quantitative locus (QTL) for PD in both populations may reveal that genes conferring PD are population-specific.