• Korean Journal of Soil Science and Fertilizer
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• v.6 no.1
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• pp.53-60
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• 1973

It is well known that upland soils in Korea are of low fertility, especially if newly reclaimed. Broadcasting of a sufficient rate of fused phosphate in addition to the normal dosage of fertilizer on such soils, may produce a crop yield comparable to that on ordinary upland soils, and the broadcasting of fertilities may build up soil fertility rather quickly. Building up fertility in this way will give a good crop growth on such newly reclaimed soils even under conditions where supplies of compost are limited. Since the precipitation in Korea is mainly concentrated in the months June through September, a complete cover of the land during this period is of major importance, requiring a well considered rotation and skilful management. If this is not possible, the application of a much of about 200 kg, straw per 1/10th ha. is recommended instead. Furthermore, contour cultivation on land with slopes less than five degrees, together with contour furrows, straw mulching, strip cultivation, interplanting, and proper selection of crops which provide a good cover of the land, is recommended on slopes varying between five and fifteen degrees and in addition, bench-terraces on slopes in excess of $15^{\circ}$.

• Korean journal of applied entomology
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• v.54 no.3
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• pp.179-189
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• 2015

In 2014, surveys were conducted in Korea to study the geographical distribution, host plants, and potential habitats of Pochazia shantungensis. The occurrence of P. shantungensis was confirmed in 43 cities and counties nationwide, and identified for the first time in Gyeongsangbuk-do. P. shantungensis has a wide range of diverse host plants comprising 113 species in 53 families, including crops, fruits, and forest trees. Since the hemipteran was first reported in Korea, 138 species from 62 families have been identified as P. shantungensis host plants. This insect feeds on the following major host plants: Malus pumila, Aralia elata, Styrax japonicus, Salix gracilistyla, Broussonetia kazinoki, Albizia julibrissin, Ailanthus altissima, Castanea crenata, Robinia pseudoacacia, and Cornus officinalis. Potential habitat was analyzed in the present study using the Maxent model with 12 variables (8 climate, 1 land cover, 1 forest type, 1 ecological zoning, and 1 distance). The model ROC AUC was 0.884, indicating a high accuracy. In the present study, precipitation of warmest quater, mean temperature of warmest quarter, forest type, and land cover were the most significant factors affecting P. shantungensis distribution, and habitat.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.6 no.10
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• pp.373-382
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• 2016

Under the Agricultural technology is influenced from climate that is requisite of seasonal. So this system will cover the problems and develop the agricultural industry as well. So far, the agricultural industry is developing however, it has the points of the weakness because of natural disasters such as wind risk and heavy snow. This paper designs system to change vinyl on the greenhouse. This is a preliminary study for the real-time feedback control of greenhouse. The study developed a wireless IoT sensor system based on authentic technology capacities, to integrate with the protected horticulture Management System. These system was used to evaluate the levels of the snow cover and wind through IoT devices. The existing greenhouse uses the warm water to clear snow or to change methods. This system will recover by changing the vinyl which is covered outside of the greenhouse. The points of the system is changing vinyl to spin pipe. It is contained extra vinyl. The effects of this system are minimized labor protected crops from natural disasters. For this purpose, the study first developed a wireless IoT sensor unit that integrates an MEMS device and wireless communication module. Also, the study developed an operating program that enables real-time response measurement. It will help operational and maintenance greenhouse as a result.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.425-431
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• 2014

Most fields in highland areas are covered with rye or hairy vetch for conservation during a fallow. However, using cover crops needs an effort to sow, and this makes top soil more vulnerable to loss due to surface disturbances. The aims of this study were to develop an automatic seeding-regulator device using a low-price, extensive-use GPS sensors and a DC motors and to evaluate a working efficiency of it after adaptation to partial tillage machine for reducing seeding effort. The amount of runoff water and soil loss was evaluated with partial tillage and simultaneous-seeding after harvesting soybean, in 17% slope lysimeters. In results, the seeding amount with the machine speed was stable between $0.5{\sim}0.8m\;s^{-1}$ of working sections. The automatic control device of seeding-rate could be enough to solve the slip problems of power selecting supply system or five four-wheel drive device. In partial tillage and simultaneous seeding, runoff water was 11.6% ($1.8m^3ha^{-1}$) of the scatter-seeding control ($15.5m^3ha^{-1}$) and soil loss was 13.2% ($7kg\;ha^{-1}$) of the scatter-seeding control ($53kg\;ha^{-1}$). These results suggest that partial tillage and simultaneous-seeding methods are very effective in decreasing work effort and soil loss of sloped land.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.3
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• pp.237-243
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• 1992

To determine effects of simulated acid rain on the growth and yield of rice, soybean and sesame, and on the soil acidity, two cultivars of rice, soybean and sesame were exposed twice a week to one of four simulated rain acidities[pH 2. 6, 3. 6, 4. 6 and 5. 6(control)]. The plants were protected from ambient rain by a polyethylene film cover. No visible damage due to the simulated acid rain was observed at any stage of growth for either of the crops. In rice, heading date, plant height and yield components except ripening ratio were not significantly affected by the pH ofsimulated rain, but the ripening ratio and rough rice yield linearly decreased as the pH of simulated rain was decreased. In soybean, maturing date and yield components except 100 seed weight were not significantly influenced by the pH of simulated rain, but the 100 seed weight and yield linearly decreased as the pH of simulated rain was decreased. Seed yield and the other agronomic characteristics of sesame were not significantly affected by the pH of simulated rain. Soil pH after cropping rice, soybean and sesame decreased as pH of simulated rain was decreased.

• Journal of The Korean Society of Agricultural Engineers
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• v.56 no.3
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• pp.31-38
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• 2014

Four actual cultivations were prepared and a variety of soybean was cultivated. A H-flume, an automatic water level gauge and an automatic water sampler were installed at the outlet of each plot equipped for the measurement of flow rate and its water quality. The amount of rainfall of the study area in 2013 was measured as 975.6 mm which was much lower than the annual average rainfall of 1,271.8 mm, resulting in less occurrences in rainfall-runoff events. Rainfall-runoff events were occurred three times during the rainfall event of 4~5 July, 23 and 24 August. The characteristics of NPS pollution discharge of the plots and the reduction effect of the selected BMPs were analyzed during these events. The reduction effect of straw mat and soil amendments (Polyacrylamide (PAM) and Gypsum) on runoff ratio ranged between 38.2 and 92.9% (average 71.6%). The NPS pollution load reduced between 27.7 and 95.1% (average 70.0%) by the application of rice straw mat and soil conditioner when compared with that of control plot. Soybean yield (2,133.3 kg/ha) of the straw mat covered plots increased by 14.3% when compared with control (1,866.7 kg/ha). The effect of straw mat on the yield was not economically viable if the material and accompanying labor costs were considered. The data collected and analyzed on different soil textures and crops in this study are expected to be a fundamental reference for the expansion of the results to the application nationwide and the development of NPS pollution management policies.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.2
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• pp.47-57
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• 2013

This study is to assess the reduction of non-point source pollution loads for rice straw mulching of upland crop cultivation at a watershed scale. For Byulmi-cheon watershed (1.21 $km^2$) located in the upstream of Gyeongan-cheon, the HSPF (Hydrological Simulation Program-Fortran) and SWAT (Soil and Water Assesment Tool), physically based distributed hydrological models were applied. Before evaluation, the model was calibrated and validated using 9 rainfall events. The Nash-Sutcliffe model efficiency (NSE) for streamflow using the HSPF was 0.62~0.76 and the determination coefficient ($R^2$) for water quality (sediment, total nitrogen T-N, and total phosphorus T-P) were 0.72, 0.62, and 0.63 respectively. The NSE for streamflow using the SWAT were 0.43~0.81 and the $R^2$ for water quality (sediment, T-N, and T-P) were 0.54, 0.87, and 0.64 respectively. From the field experiment of 16 rainfall events, the rice straw cover condition reduced surface runoff average 10.0 % compared to normal surface condition. By handling infiltration capacity (INFILT) in HSPF model, the value of 16.0 mm/hr was found to reduce about 10.0 % reduction of surface runoff. For this condition, the reduction effect of sediment, T-N, and T-P loads were 87.2, 28.5, and 85.1 % respectively. By handling soil hydraulic conductivity (SOL_K) in SWAT model, the value of 111.2 mm/hr was found to reduce about 10.0 point reduction of surface runoff. For this condition, the reduction effect of sediment, T-N, and T-P loads were 80.0, 83.2, and 78.7 % respectively. The rice straw surface covering was effective for removing surface runoff dependent loads such as sediment and T-P.

• Magazine of the Korean Society of Agricultural Engineers
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• v.16 no.2
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• pp.3430-3437
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• 1974

.It is very importaut to know the water consumption of crops in planning irrigation works and practicing suitable soil moisture management. For the purpose of making it clear that how much water be consumed to cultivate the Chinese cabbage, Chamber method has been applied. Main equipments in the transpiration chamber are flowers, manometer and electric thermograph. The chamber made of vynyl plate has a small entrance at the base and an exit at the top, and the ventilation in the chamber was carried out by a flower through the entrance and exit. Air-flow adjusted by an orifice manometer enters the chamber from the outside over the crop canopy through the pipe like a chimney and finally goes out to the outside. Two sets which consist of a pair of dry and wet bulb made by thermistor are installed in the entrance and exit tube, and record air temperature automatically. Evapotranspiration amount is computed from the air-flow quantity and difference in absolute humidity between at the entrance and exit of the chamber by the following equation: ET=(X2-X1)${\times}$Q where ET=evapotranspiration amount X1=absolute humidity at the entrance(g/㎥) X2=absolute humidity at the exit(g/㎥) Q=air-flow quantity(㎥) This study was carried out at the upland farm of the Institute of Agriculture Engimeering and Utilization, Suwon, Korea. from 1971 to 1973. The results obtained in this experiment are as follows: 1. The total amount of evapotranspiration of Chinese Cabbage that is cultivated in autumn is 408.1mm during growth period. 2. Chinese cabbage rapidly grows up in the second ten days of September, 40th to 50th days after seeding. At the same time, the maximum amount of evaportranspiration of Chinese cabbage is 61.6mm/10 days 3. The correlation between Pan-evaporation and evapotranspiration is high, coefficient of correlation r=0.88**, and can be shown as The following regression equation: ET=0.913E+20.273 4. Evapotranspiration is closely related with meteorological factors: r=0.85**, for insolation, r=0.76** for air temperature, respectively. 5. The percentage of evapotranspiration amount, at the beginning of growth stage, gradually increases in proportion as the Chinese Cabbage grows but is largely affected by meteorological factors after the green cover formation. 6. By Blaney and Griddle formula, evaportranspiration coefficient "K" are within from 0,85 to 1.27.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.8
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• pp.1252-1264
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• 2020

Objective: To effectively utilize crop by-product resources to address the shortage of animal feed during the dry season in Africa, the community of natural lactic acid bacteria (LAB) of corn stover and sugarcane tops and fermentation characteristics of silage were studied in Mozambique. Methods: Corn stover and sugarcane tops were obtained from agricultural field in Mozambique. Silage was prepared with LAB inoculant and cellulase enzyme and their fermentation quality and microbial population were analyzed. Results: Aerobic bacteria were the dominant population with 10⁷ colony-forming unit/g of fresh matter in both crops prior to ensiling, while 10⁴ to 10⁷ LAB became the dominant bacteria during ensiling. Lactobacillus plantarum was more than 76.30% of total isolates which dominated silage fermentation in the LAB-treated sugarcane top silages or all corn stover silages. Fresh corn stover and sugarcane tops contain 65.05% to 76.10% neutral detergent fiber (NDF) and 6.52% to 6.77% crude protein (CP) on a dry matter basis, and these nutrients did not change greatly during ensiling. Corn stover exhibits higher LAB counts and water-soluble carbohydrates content than sugarcane top, which are naturally suited for ensiling. Meanwhile, sugarcane tops require LAB or cellulase additives for high quality of silage making. Conclusion: This study confirms that both crop by-products contain certain nutrients of CP and NDF that could be well-preserved in silage, and that they are potential roughage resources that could cover livestock feed shortages during the dry season in Africa.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.6
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• pp.644-652
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• 2017

Clover, a legume crop, is a landscape crop and green manure crop that can be sowing in spring. Clover serves various roles such as landscape composition, weeds suppressing, prevention of soil loss and nutrients on sloping, atmosphere purification, and supplying nitrogen in soil. Thus, in order to utilize this crop in agricultural land, we observed its effect on growth and carbon uptake in upland soil. The plant height of clover species increased with late harvesting time and was 46.0~55.0 cm at 90 days after seeding (DAS) and the longest in red clover. The dry matter increased at 85 DAS, after that, decreased slightly. The dry matter of white clover and red clover was $3.0Mg\;ha^{-1}$ and $3.1Mg\;ha^{-1}$, respectively, and crimson clover was $2.5Mg\;ha^{-1}$, significantly lower than other clover. Crops bloomed at 90 DAS were white clover and crimson clover, the period from sowing to flowering was 78 days for crimson clover and 85 days for white clover. The nitrogen content of the clover species was $12.0{\sim}29.3g\;kg^{-1}$, with the highest of $29.3g\;kg^{-1}$ for white clover. The carbon content of clover species was similar in all clover species, but carbon uptake was high in white clover and red clover, and lowest in crimson clover. The carbon uptake of the plant increased to 85 DAS and then decreased. Based on the clover growth and carbon uptake, white clover and red clover were promising when sown in spring.