• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.875-886
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• 2015

The upland soils (56 samples) from organic farms in Gyeonggi-do (12 sites), Gangwon-do (8 sites), Chungcheong-do (14 sites), Gyeongsang-do (4 sites), Jeollado (18 sites) in Korea were collected and their physical and chemical properties were analyzed by RDA's methods. In the results of physical property, the bulk density of soils averaged $1.14Mgm^{-3}$ (surface soil), $1.38Mgm^{-3}$ (subsoil), respectively. The porosity of them was 57%, 48%. Organically managed soil's (OS) bulk density was lower than conventional soil's but OS's porosity was a little higher than conventionally managed soil in surface soil. The depth of plough layer in organically managed soils was 21.2 cm indicating that the organic farming had good effect on soil physical property. In the results of chemical property, the surface soil pH was 6.9 and the contents of organic matter (OM) was $26gkg^{-1}$, available phosphate (Avail. $P_2O_5$) was $554mgkg^{-1}$, exchangeable calcium (Exch. Ca) was $8.9cmol_ckg^{-1}$, exchangeable potassium (Exch. K) was $0.89cmol_ckg^{-1}$, exchangeable magnesium (Exch. Mg) was $2.0cmol_ckg^{-1}$. The subsoil pH was 6.8 and the contents of OM was $21gkg^{-1}$, avail. $P_2O_5$ was $491mgkg^{-1}$, exch. Ca was $7.9cmol_ckg^{-1}$, exch. K was $0.68cmol_ckg^{-1}$, exch. Mg was $1.8cmol_ckg^{-1}$. The nutrient accumulation emerged in organic farming. Compared to the optimum nutrient range for the conventional upland soils, the exceed rate of pH, OM, available phosphate, and exchangeable Ca, K, and Mg was 79, 52, 64, 84, 66% and 55%, respectively, which mainly resulted from the over-application of lime materials or livestock manure compost. With these results it is suggested that organic farm need to reduce the use of inputs, which make soil alkalification or nutrient accumulation. More study on effects of inputs on lowering soil pH from alkalification could help organically managed soil to be improved.

• Agrochemical news magazine
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• v.22 no.8 s.171
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• pp.14-17
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• 2001

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.300-300
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• 2009

화학비료를 이용할 수 없는 유기농업에서의 양분관리를 위해서 녹비, 퇴비, 유박 등을 주 원료로 하는 유기질비료 등 다양한 유기물이 농경지에 투입되고 있다. 그러나 다양한 성분 및 탄소/질소비로 이루어진 유기물은 토양 중에서 분해되는 속도가 다르고, 토양수분함량, 통기성, 온도 등과 같은 토양조건에 따라서도 분해속도가 크게 차이가 난다. 본 실험에서는 유기농업에서 시비원으로 자주 이용하는 퇴비, 유박비료, 녹비조건의 알팔파 등을 이용하여 무기화율 및 양분이용률을 화학비료와 비교하였다. 농경지 투입시 유기물은 질소양분양(21kg N/10a)을 동일하게 투입하였으며 화학비료는 기비(전체량의 1/3)만을 투입하였는데 알팔파, 유박비료의 경우 노지조건에서 토양처리 후 1달 내에 가장 높은 무기화율을 보였으며 수분조건이 제한된 무기화통내에서의 무기화도 2개월 내에 대부분 이루어지는 것으로 나타났다. 수딘그라스를 2개월 재배한 결과 화학비료 질소 양분이용율은 70%, 탄질비가 낮은 유박 및 알팔파는 40%내외, 탄질비가 높고 분해가 어려운 가축분 왕겨퇴비는 10%에 불과했다. 즉 화학비료 대비 유기물 양분(질소)의 비효화 율은 알팔파는 60%, 유박비료는 54%, 퇴비는 14% 였다. 또한 화학비료(100%) 대비 인산 이용률(유박: 296%, 알팔파: 660%, 퇴비: 36%로, 인산의 이용율이 높은 것은 유기물로 투입된 인산의 량이 화학비료보다 낮아 상대적으로 유기물질에 의한 작물의 인산이용율이 높고, 화학비료는 토양중 고정화가 작물생육 초기에 일어나는데 비하여 유기물질은 서서히 분해되면서 작물에 흡수되어 인산이용율이 높은 것으로 추정된다. 수단그라스 1차수확 후 포장침수로 인한 생육불량으로 전 생육 과정을 통한 양분흡수율은 측정할 수 없었다.

• Agrochemical news magazine
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• v.22 no.6 s.169
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• pp.6-7
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• 2001

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2011.06a
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• pp.117-127
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• 2011

The paper outlines farming systems, including organic, in the UK, and provides a context for the use of biological nitrogen (N) from legumes, especially clovers, and manure in organic grassland systems. As N is dynamic within organic ruminant/grassland systems its pathway is described, including its loss and resultant environmental impact. Improvements in the predictability of response to biological N, its role in reducing the carbon footprint of ruminant products and potential to improve its efficiency are discussed.

• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.813-827
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• 2015

This study was conducted to evaluate the effect of organic inputs on soil properties in a newly reclaimed organic soils. The soil of the experiment site was very low in soil fertility and the physico-chemical properties were poor. Several organic input treatments with different source of nutrient were placed, including compost in combination with green manures for organic agricultural practices, chemical fertilizers for conventional agricultural practices, and control without fertilizer. The experiment was conducted with continuous cropping system during 3 years. The chemical properties concentration in compost+green manure treatment was increased continually compare to control and chemical fertilizer treatment, and closed to the recommended rate of fertilizer. The organic matter value for compost+green manure treatment was increased from 0.86~0.96% to 2.00~2.29% by continuous nutrient supply of compost and green manure. However, further investigation on increasing of organic matter value for 3 years is necessary to monitor carefully during the long-term because it will help to clarify the all mechanisms of organic matter on organic input application way. The available phosphate value for compost+green manure treatment was generally increased from 21.9~27.1 mg/kg to 182.0~394.1 mg/kg. In case of exchange cation, the concentration for compost+green manure treatment was increased during 2 years within the range to the recommended rate of fertilizer, however, it is expected to cause a rather over supply for 3 years.

• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.767-779
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• 2015

soil microbial activities and diversities in a newly reclaimed soil. Soil chemical properties, population of microbe, microbial biomass, and properties of microbial community were investigated under 4 different treatment (animal manure compost+green manure, chemical fertilizer, and without fertilizer). The experiment was conducted for 3 years from 2012 to 2014. The most of chemical properties in the animal manure compost+green manure treatment were increased continually compare to chemical fertilizer and without fertilizer. The population of bacteria and fungi were higher in the animal manure compost+green manure treatment, however, there was no difference on actinomyces. Soil microbial biomass C content was higher in the animal manure compost+green manure treatment than in chemical fertilizer and without fertilizer. Biolog examination showed that catabolic diversities of bacterial communities were higher in the treatment of animal manure compost+green manure. It was showed that principle component analysis of the Biolog data differentiated the organic matter amended soils from NPK and control. These results indicated that application of animal manure compost+green manure had a beneficial effect on soil microbial properties.

• Korean Journal of Organic Agriculture
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• v.25 no.1
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• pp.161-170
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• 2017

To investigate the influence of long-term organic cultivation on soil characteristics, chemical properties of 35 soils in the national scale organically managed over 10 years were analyzed. 57% of soils which were managed by the materials containing livestock manure have higher nutrient concentration than the materials not containing livestock manure. The decomposed composts (containing livestock manure) had higher amount of $P_2O_5$, CaO, $K_2O$ than organic fertilizers (not containing livestock manure). In the results, the nutrient concentration of soils in long-term organically managed was higher than optimum range of upland soil, especially pH 6.9, available phosphorus (Av. $P_2O_5$) 744 mg/kg, exchangeable calcium $9.4cmol_c/kg$, potassium 2.51 cmolc/kg. On the other hand, more than 50% of soils had lower concentration of exchangeable magnesium than optimum range (soil nutrient distribution was unbalanced). It is suggested that farmers have to be careful to apply organic materials, especially containing livestock manure.

• Korean Journal of Organic Agriculture
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• v.3 no.1
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• pp.1-9
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• 1994

한국의 급속한 경제발전과 공업화 과정에서 특히 연령층이 20∼49세의 젊은 농촌의 여성들이 대단히 많이 도시로 이동하였다. 농촌에서 농작업에 종사하는 여성들은 주로 수도, 채소 및 과수재배에서 많은 육체적인 노동을 하고 있다. 특히 농촌에서 농약을 산포하는 일은 여성들이 많이 하고 있다. 1960년도 이후 1992년도에 달하는 지난 32년 기간동안에 국민소득 수준이 1%증가됨에 따라서 농촌여성이 667명씩 감소되었다는 사실이 단순회귀 분석에 의하여 증명되었다. 그리고 농약을 산포한 여성들의 암에 의한 사망률이 산포하지 아니한 여성들 보다 높다는 사실이 실증적으로 증명되었다. 1968년도에 2정보의 농경지 규모에서 전체 노동시간 가운데 여성의 노동시간이 차지하는 비율이 55,72%로서 나타나고 있다. 그런데 1992년도에 동일규모에서 여성들이 노동시간이 차지하는 비율은 44.58%로서 감소되고 있다. 앞으로 건전한 농촌의 환경을 지속적으로 보존하기 위하여서는 여성들의 귀중한 생명을 보존하고 동시에 소비자들의 건강을 보호하는 유기농법이 실천되어야 할 것이다.

• 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.