• The Korean Journal of Pesticide Science
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• v.11 no.4
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• pp.299-304
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• 2007

Surveying, laboratory and field trial were performed to elucidate the causes of non-spinning syndrome of silkworm, Bombyx mori, abnormal symptoms of silkworm instars observed in certain sericultural fanning region. Mortality and growth of silkworm was still influenced by feeding the mulberry leaves sprayed with 10,000 fold diluted solution of standard spray of diflubenzuron WP (25%). Mortality and growth of silkworm fed with diflubenzuron-sprayed mulberry leaves with recommended spray solution were entirely affected even six weeks after spraying irrespective to the instars. Larval period of 5th instar and cocooning duration of silkworm was not affected in case 50m of buffer zone has maintained in near-by orchard field sprayed with diflubenzuron WP (25%). However, survival rate of pupae was not influenced in case 100 m of buffer zone has kept. Insect growth regulating insecticides were required to keep a certain distance of buffer zone when sprayed with water-diluted solution, 100 m from the application site at least in order to prevent contamination of the spraying drift by the chemicals.

• Korean journal of applied entomology
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• v.53 no.4
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• pp.323-329
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• 2014

Population of fruit flies was monitored by using methyl eugenol trap during 2010-2011 in Yezin, Myanmar. Population numbers were analyzed with meteorological factors including rainfall, temperature, relative humidity and duration of sunshine. Samples of mango, guava, and jujube fruits were collected from orchards. The fruits were kept in containers so that the species of flies infesting the fruit could be identified when the adult insects emerged and to assess damage caused by fruit flies. Regression analyses indicated that populations of fruit flies were observed to be positively correlative with rainfall, minimum temperature and relative humidity, and negatively correlative with the duration of sunshine. Eleven species of fruit flies, Bactrocera arecae, B. carambolae, B. correcta, B. dorsalis, B. kandiensis, B. latilineola, B. malaysiensis, B. neocognata, B. raiensis, B. verbascifoliae, and Carpomya vesuvina, were identified. B. correcta and B. dorsalis were the most abundant and accounted for 29.3% and 28.6% of total emerged adults in the different fruit samples. The highest percentage of fruit damage was observed on guava ($59{\pm}15.4$), followed by mango ($35.5{\pm}12.1$) while the lowest was recorded on jujube ($18.5{\pm}7.9$).

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.3
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• pp.280-287
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• 1997

This study was carried out to investigate agricultural status and soil fertility of Bonghwang-cheon watershed area which is located at Chodong-myeon, Milyang-si. The acreage of arable land was about 1,209ha, and the population was 3,706 people. Out of total arable land, paddy was 64.4%, upland 19.6% and orchard 16.0%. Chicken was the largest in the number of livestock and poultry, but pig seems to contribute most severly to water pollution. The geology in the lower stream was alluvium but andesite and derivated materials from it were occupied most upland areas. Tuff was scattered in the small area near by the alluvium of Nakdong river, and diorite and granodiorite were located at the low hill and mountains respectivately. The principal paddy soils in the area were Geumgog, Jisan and Imgog series etc of fine loamy on sloped valleys and fans. The Pyeongtaeg series, fine silty family of imperfectly drained on plain was irrigated by Chodong reservoir. The clayey Honam series on alluvium was distributed along the low hill while Gyuam series, coarse silty alluvial soil way close to Nakdong river. In chemical properties of soils, the vinyl house soils were higher in EC, and orchard soils in OM, $P_2O_5$, exchangeable canons than other soils.

• Weed & Turfgrass Science
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• v.5 no.2
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• pp.71-81
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• 2016

This study was conducted to investigate the weed occurrence and distribution on the orchard fields (apple, pear, peach, grape) at 387 sites in Chungbuk province of Korea from May to September in 2015. From the result of this survey, 200 weed species in 47 families were identified and classified to 82 annuals, 40 biennials and 78 perennials. Based on the occurrence ratio, the most dominant weed species in Chungbuk province orchard fields were higher in order of Digitaria ciliaris (4.12%), Echinochloa crus-galli (3.60%), Stellaria aquatica (3.45%), Artemisia princeps (3.07%) and Chenopodium album (3.06%). The composition of major occurred weed families, Compositae, Poaceae, Leguminosae and Cyperaceae were 21, 9, 6 and 6%, respectively. Coefficient of similarity between a various orchards based on the degree of dominance were ranged from 68.7-91.8%. The most important weed species at apple, peach, grape was Digitaria ciliaris while these for pear was Poa annua. Fifty-one exotic weed species were also identified. The results of this study could be useful information for estimation of future weed occurrence, weed population dynamics and establishment of weed control methods on the orchard fields in Chungbuk province of Korea.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.9 no.3
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• pp.257-265
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• 2016

In this study, an optimal design for motor-driven track type traveling system applied into high clearance working machineries in orchard is proposed. Tractive performance and hill climbing ability were predicted and evaluated for the optimal motor traveling system by taking into account of soil characteristics in orchard utilizing the high clearance working machineries. Design criteria for tractive performance were based on the traction force calculated from tractive effort subtracted by motion resistance, while hill climbing ability had its design criteria that fulfill the climbing 20% slope ground at a speed of 3km/h. Based on the evaluation results of traction and climbing ability, two DC48V, 4500rpm, 1.6kW AC motors were independently applied to both left and right side of orbits; each motor is designed to transmit power on driving sprocket of track type traveling system via 50:1 reduction gear ratio. The motor-driven track type traveling system developed in the study found to have 396 kgf of tractive force, which is 12.5% higher than climbing resistance at orchard soil having 20% slope ground (352 kgf), demonstrating sufficient tractive performance and hill climbing ability.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.2
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• pp.122-128
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• 2013

This study was carried out to evaluate the soil dehydrogenase activity and microbial biomass C with soil type and land use in cropland of JeJu region. Soil chemical properties, dehydrogenase activity, and microbial biomass C were analyzed after sampling from upland (50 sites), orchard (50 sites), paddy (30 sites), horticultural facility (30 sites) in March. Average pH values was at 6.3 in upland soil, however soil chemical properties showed a large spatial variations in both orchard and horticultural facility soil. The Zn and Cu contents increased by the continuous application of pig manure compost in some citrus orchard soil. Soil dehydrogenase activity and microbial biomass C were higher in non-volcanic ash than in volcanic ash soil regardless of land use type. Soil dehydrogenase activity was two to four times higher in upland than in the others. It was at 38.7 ug TPF $24^{h-1}g^{-1}$ in non-volcanic ash of upland soil. Microbial biomass C content was very high in horticultural facility soil and it showed at 216.8 $mg\;kg^{-1}$ in non-volcanic ash. Soil dehydrogenase activity showed a positive correlation with organic matter ($r^2$=0.59), Zn ($r^2$=0.65), and Cu ($r^2$=0.66) in non-volcanic ash horticultural facility soil. There was a negative correlation ($r^2$=0.57) between soil organic matter and dehydrogenase activity in volcanic ash upland soil.

• Korean Journal of Environmental Biology
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• v.36 no.4
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• pp.567-575
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• 2018

The soil physical quality is a core factor in achieving two of sustainable agriculture's goals: productivity and environment. The purpose of this study was to assess changes in soil physical properties for nearly a decade through periodic monitoring of three cultivation types: upland, orchard, and paddy. Field surveys and lab analysis were conducted to determine the soils physical properties after every 4 years; upland (2009, 2013, and 2017), orchard (2010 and 2014), and paddy (2011 and 2015). In each year soil samples from 162-338 sites were collected. The bulk density of upland subsoil decreased from $1.53Mg\;m^{-3}$ to $1.50Mg\;m^{-3}$ while the plowing depth and subsoil organic matter increased from 13.7 cm to 19.5 cm and from $12.6g\;kg^{-1}$ to $18.3g\;kg^{-1}$ respectively during the period 2009-2017. Plowing depth for orchard increased from 16.7 cm to 18.9 cm. However, organic matter content decreased from $15.9g\;kg^{-1}$ to $15.4g\;kg^{-1}$ during the 2010-2014 period. For paddy, plowing depth and subsoil organic matter decreased from 17.5 cm to 16.7 cm and from $17.5g\;kg^{-1}$ to $15.8g\;kg^{-1}$ respectively. The subsoil bulk density increased from $1.47Mg\;m^{-3}$ to $1.52Mg\;m^{-3}$ from 2011-2015. Excess ratio for soil physical standards increased from 16% to 22% in orchard, 56% to 62% in paddy, and decreased from 41% to 29% in upland. The overall soil physical quality had been ameliorated for upland, but degraded for paddy. Improved tillage practices and application of appropriate organic matter is necessary to enhance the quality of soils, especially in the paddy field.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.348-356
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• 2016

Carbon dioxide ($CO_2$) gases concentration in atmosphere has been growing since preindustrial times. By sequestering a large amount of atmospheric carbon (C), terrestrial ecosystems are thought to offer a mitigation strategy for reducing global warming. Woody agro-ecosystems such as fruit tree are among the least quantified and most uncertain elements in the terrestrial carbon cycle. $CO_2$ and energy fluxes were measured by the eddy covariance method on a 15-year old apple orchard of South Korea in 2006. Environmental parameters (net radiation, precipitation, etc.) were measured along with fluxes. The results showed that during late June, the ability to sequestrate C was significant at an apple orchard ecosystem and it reached on the peak of $-6.5g\;C\;m^{-2}\;d^{-1}$. We found that in the apple orchard, the daily average of net ecosystem exchange of $CO_2$ (NEE) and cumulative NEE on a yearly basis were $-1.1g\;C\;m^{-2}$ and $-396.9g\;C\;m^{-2}$, respectively. These results reveal that there is high carbon sequestration in the apple orchard of South Korea, which is the same magnitude with repect to that of a natural forested ecosystem of the same biome rank (temperate-humid deciduous forest).

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.10a
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• pp.375-379
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• 2010

우리나라는 국토의 70%가 산림인 관계로 주택, 축사, 과수원, 비닐하우스에서 쓰레기 소각장, 주유소, 가스저장소 등 위험 시설까지 많은 시설물 들이 산림에 인접하여 위치하고 있다. 이러한 시설물은 산불의 발생 원인이 될 수 있으며, 동시에 산불 발생 시 심각한 위험에 노출될 수도 있다. 본 연구에서는 이러한 시설물의 산불 위험에 대하여, 지자체 산림 담당 공무원과 소방서 공무원의 인식에 대하여 설문조사를 실시하였다. 향후, 본 연구의 결과를 통해 산불 예방정책의 기본 자료로 삼고자 한다.

• Korean Journal of Organic Agriculture
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• v.10 no.3
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• pp.67-77
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• 2002

This study was conducted to investigate an effects on ago-chemical alternative materials such as the wood vinegar, a lactic acid bacteria serum, the fermented plant juice, the brown rice vinegar and a Chitosan used for amount and qualities of fruits and to examine the pest protection efficiency for their uses in the apple and pear orchard farms. An apple yields in the orchard cultivated with using the ago-chemical alternative materials without appling the fertilizer and pesticides were decreased at 56% relative to the conventional farming practice method. Also, it was indicated that there was difficult to produce the fruits with marketability because the small sizes of fruits were produced. For the quality of fruits, the brix of apple produced in the orchard cultivated with using the ago-chemical alternative materials was similar, but Vitamin C content was greater than that of the conventional farming practice method. As a results of treating with the wood vinegar, a lactic acid bacteria serum, the fermented plant juice, the brown rice vinegar and a Chitosan instead of applying pesticides, the fruit disease in the Chitosan treatment was a little decreased, but was great occurred in the other treatments compared with the conventional farming practice mehod. However, it observed that brix and Vitamin C content of apple produced in the Chitosan, brown rice vinegar, fermented plan juice and fish amino acid treatments and in the Chitosan, brown rice vinegar, charcoal power and peat moss treatments were greater than those of the conventional farming practice method, respectively. Over all, it considered that there was very difficult to manage the orchard depended on the ago-chemical alternative materials without appling the chemical fertilizer and pesticides in the apple orchard, but it might be proper to use the ago-chemical alternative materials as an auxiliary means to decrease the appling amount of chemical fertilizer and pesticides. Furthermore, the general effects on the ago-chemical alternative materials to the perennial fruits should be investigated with considering the changes of soil fertility, soil microbial status and natural enemy creatures after treating them for a long time.