• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.228-234
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• 2004

In organic farming, nutrients for the crop production are mostly supplied by compost containing various organic materials. The long-term organic cultivation would result in continuous changes of soil chemical properties and fertility. The aim of this study was to investigate the contribution of long-term organic cultivation to the soil fertility in Korea focusing on the chemical properties of soil. Soil samples were collected from organic farms that had been cultivated for 8-10 years after certification of organic product through the conversion periods of 2-3 years. Thereby each organic farm had acquired optimal cultivating techniques and soil condition. We separated organic farms into three groups by cultivating crops, i.e. leaf vegetables, fruit vegetables and fruit trees. In each group, five representative farms were chosen in order to investigate the relationships between application rate of compost and nutrient contents in soil. The application rate of compost was approximately $10-15Mg\;10a^{-1}$ for the first 2-3 years at the beginning of organic farming and then reduced to a rate of $3-4Mg\;10a^{-1}$ after stabilization of organic matter content in soil with $30-50g\;10a^{-1}$. However, the continuous organic farming for 8-10 years resulted in accumulation of nutrients, especially of P, in soil probably due to the excessive amounts of compost applied. In conclusion, we suggest that the application rate and organic sources of compost should be decided on the basis of P content in soil by soil testing and thereafter the lack of soil N content for crop cultivation should be compensated by crop rotation with such as legumes. This might be an approach to the original meaning of organic farming as an environmental friendly agriculture.

• Korean Journal of Environmental Agriculture
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• v.3 no.2
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• pp.23-29
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• 1984

Agricultural soil samples collected from 121 sites (plastic film house 59, up-land 30 and orchard 32 sites) were evaluated by steam distillation and GLC-ECD analysis for organochlorine pesticides (${\gamma}-BHC$, heptachlor, p,p'-DDE, dieldrin, p,p'-DDD, and p,p'-DDT) in Jeollanam-Do area. Total residues of organochlorine pesticide in orchard, plastic film house and up-land were 0.415, 0.234 and 0.156ppm, respectively. Ninety-four percent of total residue was p,p'-DDT and its homologues (p,p'-DDE and p,p'-DDD). ${\gamma}-BHC$ was detected in all soil samples at $trace{\sim}0.050ppm$ range. Residue levels of organochlorine pesticide increased in the order of p,p'-DDE, ${\gamma}-BHC$, heptachlor, dieldrin, p,p'-DDT and p,p'-DDD.

• Journal of Practical Agriculture & Fisheries Research
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• v.20 no.2
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• pp.57-72
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• 2018

In order to extract meaningful information from the excellent farming settlement cases of young farmers published by KNCAF, we studied the key words with text mining and created a word cloud for visualization. First, in the text mining results for the entire sample, the words 'CEO', 'corporate executive', 'think', 'self', 'start', 'mind', and 'effort' are the words with high frequency among the top 50 core words. Their ability to think, judge and push ahead with themselves is a result of showing that they have ability of to be managers or managers. And it is a expression of how they manages to achieve their dream without giving up their dream. The high frequency of words such as "father" and "parent" is due to the high ratio of parents' cooperation and succession. Also 'KNCAF', 'university', 'graduation' and 'study' are the results of their high educational awareness, and 'organic farming' and 'eco-friendly' are the result of the interest in eco-friendly agriculture. In addition, words related to the 6th industry such as 'sales' and 'experience' represent their efforts to revitalize farming and fishing villages. Meanwhile, 'internet', 'blog', 'online', 'SNS', 'ICT', 'composite' and 'smart' were not included in the top 50. However, the fact that these words were extracted without omission shows that young farmers are increasingly interested in the scientificization and high-tech of agriculture and fisheries Next, as a result of grouping the top 50 key words by crop, the words 'facilities' in livestock, vegetables and aquatic crops, the words 'equipment' and 'machine' in food crops were extracted as main words. 'Eco-friendly' and 'organic' appeared in vegetable crops and food crops, and 'organic' appeared in fruit crops. The 'worm' of eco-friendly farming method appeared in the food crops, and the 'certification', which means excellent agricultural and marine products, appeared only in the fishery crops. 'Production', which is related to '6th industry', appeared in all crops, 'processing' and 'distribution' appeared in the fruit crops, and 'experience' appeared in the vegetable crops, food crops and fruit crops. To visualize the extracted words by text mining, we created a word cloud with the entire samples and each crop sample. As a result, we were able to judge the meaning of excellent practices, which are unstructured text, by character size.

• Journal of Bio-Environment Control
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• v.21 no.3
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• pp.286-293
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• 2012

This study was initiated to find out the suitable perennial ground covers naturally grown in thirteen organic orchards in Chonnam Province as a organic nutrient source for maintaining annual fruit tree growth. The ground covers were observed in April, June, and August in the orchards. Agropyron tsukusinense and Panicum virgatum observed in April and June, respectively, produced the highest dry weight, which increased amounts of N, $P_2O_5$, and $K_2O$, mineralizing from the residue in the ground covers. The occurrence of perennial ground covers in August decreased compared to April and June. Amount of residue in mowed Agropyron tsukusinense and Panicum virgatum satisfied nutrient demand (N; 20 kg/10a, $P_2O_5$; 11 kg/10a, and $K_2O$; 19 kg/10a) to achieve the annual growth of twenty-year old fruit tree.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.4
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• pp.71-80
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• 2001

In order to evaluate the effectiveness of the organic and natural farming techniques, the actual conditions of the techniques were surveyed and some crops were cultivated in situ. The contents of available $P_2O_5$, exchangeable $Ca^{2+}$ and organic matter of the organic and natural farming soil as well as soil pH were higher than those of the non-organic and non-natural farming soil, and especially the content of organic matter amounting 54.0 g/kg was dominant. Income of the farmers cultivating the different crops with the organic and natural farming was high in order of red pepper in vinyl house > cucumber in vinyl house > fruit(pear) > lettuce in vinyl house > rice. The agricultural materials used in organic and natural farming were ranged from 22 to 25 kinds, representing low pH amounted from 2.9 to 4.5 and low contents of fertilizer ingredients. The expense for purchasing the materials was from three to five times higher than that of soil testing plot. The yields of test crops in the organic and natural farming plots were lower than those of soil testing plot, and the efficiencies of the disease and pest control by the application of the substitutes for pesticide were lower than those by pesticides.

• The Korean Journal of Pesticide Science
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• v.12 no.4
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• pp.375-381
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• 2008

A new disease causing skin sooty dapple symptoms on fruits, leaves, and young shoot of Asian pear occurred in Korea. However, no chemical control approaches has been developed to control this disease. To investigate ecological aspects of this disease, we conducted field surveys in the high or low disease occurred orchards. The years with heavy rainfall caused severe occurrence of the skin sooty dapple disease than the years with lower rainfall during all growth stages of pear fruit. Different fruit-wrapping bags did not prevent occurrence of skin sooty dapple disease, and lesion numbers were higher in lower parts of fruit equatorial line inside of fruit-wrapping bags. There is a direct correlation between occurrence of the skin sooty dapple disease and frequency of fungicide application in the orchards. Among the tested commercial fungicides, thiophanate-methyl WP and penconazole WP completely inhibited the growth of the Cladosporium sp. in in vitro studies but little protection was observed in the field following fungicide applications. However, application of lime sulfur combined with the use of fruit-wrapping bags most effectively reduced incidence of the disease in the field. Our results suggest that skin sooty dapple disease could be a serious problem in sustainable organic pear farms and effective control methods for this disease urgently required.

• Korean Journal of Organic Agriculture
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• v.14 no.1
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• pp.55-67
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• 2006

A survey of 31 organic farmers were conducted to investigate the actual conditions of organic matter application. The amounts of organic matter application in the fields were higher in order of fruit, vegetable and rice farm. The average was 50 ton/ha in vegetable farms. In the green vegetable farms saw dust and animal manure were mainly utilized to make compost. Rice straw, wood chip, and forest bushes were also used for composting. In the fruit vegetable farms materials relatively lower in nitrogen content such as rice straw and cattle manure were used in vegetative period and materials higher in nitrogen content such as oil cake and wild grass were used in reproductive phase. Nutrient balance investigated in the farm in Icheon region who produce lettuce, angelica, and kale continuously in one cropping year indicated surplus in three major nutrients. Nitrogen and phosphorous were in excess by 29 and 10 kg respectively in the organic rice farm in yang-pyoung region. While soil chemical properties in the organic farms are within the adequate range in open field, it is much higher than the limits in the greenhouse soils. Overall application of organic matter is in an oversupply state. This results suggested that the organic matter management should be based on the soil conditions for sustainable cultivation. Chemical composition of organic matters and soil test reports should be considered prior to the application of organic matter.

• 한국공간정보시스템학회:학술대회논문집
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• 2005.05a
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• pp.243-248
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• 2005

우리나라의 농업은 주곡의 지속적인 자급기반을 마련하고 이제 단순한 농사형태에서 벗어나 새로운 소득작목을 개발하고 합리적인 경영개선을 통하여 소득을 높이는 상업농시대에 접어들게 되었다. 따라서 상업농시대에는 농업도 새로운 기술을 바탕으로 질 높은 농산물을 안정적으로 생산공급할 수 있는 기술의 확보가 더욱 요구되고 있다. 최근 농산물수입개방 시대에 접어들게 되면서 우리 농산물도 국제경쟁력향상을 위한 품질향상 및 새로운 소득작물의 개발이 절실히 요구되는 시점에 와있다. 여러 지방지치단체에서 그 지방에 알맞은 소득작물을 개발하여 많은 소득을 올리고 있는 사례를 많이 볼 수 있다. 예로서 보성의 녹차, 무안의 무화과, 구례의 오이 등이 대표적인 예라고 할 수 있다. 여러 농업연구기관에서도 과학적인 토양연구로 세부정밀토양조사를 실시하고 작물재배의 부적지에 대해서는 토양개량방법을 연구하고 있으며 그에 따른 시비추천과 소득작물의 적지적작추천을 하고 있다. 국내에서도 GIS의 발전 및 RS의 발전과 더불어 친환경농업의 일환으로 정밀농업분야에 많은 관심이 집중되고 있다. 정밀농업은 농업생산기술 분야에서 아직 생소한 접근방법으로서 여기에서는 지구측위시스템(GPS)와 지리정보시스템(GIS), 원격탐사(RS)기법들이 많이 응용되고 있다. 또한 농업의 1차(식량생산)적인 목적에서 2차, 3차(소득증대 및 부가가치 증대)적인 목적으로 변화되고 있다. 각 지자체에서 그 지역에 적합한 농산물 재배를 위한 재배단지 확산방안 연구가 진행중에 있으며, 과거 토양속성인자를 가지고 재배적지 선정을 해왔으나, 본 연구에서는 GIS와 RS을 중첩하여 적지선정에 관한 최적의 시스템을 구현하였다. 이런 적지 선정을 통하여 유기농업의 실현을 도모하여 소비자의 욕구에 맞는 작물 생산 및 농촌관광단지 조성을 통해 부가가치증대 및 소득증대를 꾀함으로 농촌문제 해결에 도움이 될 것으로 기대된다. 본 연구를 통해 GIS 와 RS의 기술이 농촌분야에 더 효율적으로 적용될 것으로 기대되며, 농업기술센터를 통한 정보제공을 함으로써 대농민 서비스 및 농업기관의 위상이 제고 될 것으로 기대된다.

• Korean Journal of Environmental Agriculture
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• v.1 no.1
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• pp.1-13
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• 1982

Composite soil samples from 236 sites representing paddy field, up-land, orchard and plastic film house were examined for organochlorine residues by GLC-ECD. Detection frequencies and residual levels of most persistent organochlorine residues in the soil samples were found to depend on the cropping practices. Highest organochlorine residues were found in orchard soils and followed, in decreasing order, plastic film house, up-land and paddy field soils. ${\alpha}-Endosulfan$, dieldrin, p,p'-DDD and p,p'-DDT were responsible for the observed high organochlorine residues in the orchard soils. ${\alpha}-BHC$ and ${\gamma}-BHC$ were detected in all 236 soil samples. The mean residue levels of both BHC isomers were, however, remained fairly low. Residues of PCNB and ${\alpha}-endosulfan$ in native soils are reported, for the first time, in present work. PCNB was present in up-land plastic film house soils while ${\alpha}-endosulfan$ was found in all agricultural soils studied. High levels of p,p'-DDT and dieldrin were discussed in relation to crops cultivated, amount and duration of the pesticides usage. Need for continued observations on the persistent residue of pesticides in soils, already banned for general use, is emphasized.

• Korean journal of applied entomology
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• v.59 no.3
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• pp.257-264
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• 2020

The purpose of this study was to investigate the attraction distance range of pheromone traps used in the control of stink bugs, which are a problem in persimmon orchards, and the effects of sticky traps in increasing the efficiency of pheromone traps. Labeled individuals were released and then recaptured on pheromone and sticky traps. Riptortus clavatus was attracted to pheromone traps up to 60 m away. The capture rates of R. clavatus on sticky traps were 35%, 27%, 34%, 2.9%, and 0.6% after 0, 1, 2, 3, and 4 weeks To improve clarity, II have added this information from the details shown in the figures. Please check whether you agree.of exposure of the traps to the environment, respectively. Besides, when both pheromone and sticky traps were used at the same time following the release-recapture method, the capture rate of R. clavatus was 12 times higher than that by using pheromone traps only.