• Journal of Korean Society on Water Environment
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• v.28 no.3
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• pp.436-443
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• 2012

This research was focused on the effect of rice straw and rice straw mat on the reduction of upland field non-point source (NPS) pollution discharges. Six experimental plots of $5{\times}22m$ in size and 3% in slope prepared on gravelly sandy loam soil were treated with control, rice straw cover and rice straw mat cover. Radish in Spring growing seasons were cultivated. NPS pollution discharge was monitored and compared with respect to the treatments. The surface cover rate of rice straw and rice straw mat right after the treatments was 64.7% and 73.7%, respectively. Rainfall of the 16 monitored events ranged from 12.8 mm to 538.2 mm. Runoff coefficient of the events was 0.01~0.67 in control plot, 0~0.63 in rice straw plot and 0~0.45 in rice straw mat plot. The reduction of runoff compared to the control plot was 5.4~99.7% in rice straw plot and 32.9~100% in rice straw mat plot. The reduction of NPS pollution load was 52.0% for SS, 28.5% for T-N and 35.2% for T-P in rice straw plot and 79.8% for SS, 68.3% for T-N and 53.3% for T-P in rice straw mat plot. This research revealed that rice straw mat cover on the soil surface could not only increase the crop yield and farmer's income but also reduce the NPS pollution loads significantly.

• Korean Journal of Remote Sensing
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• v.22 no.2
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• pp.101-110
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• 2006

The accuracy of rural land cover using airborne multispectral images and LEAR (Light Detection And Ranging) data was analyzed. Multispectral image consists of three bands in green, red and near infrared. Intensity image was derived from the first returns of LIDAR, and vegetation height image was calculated by difference between elevation of the first returns and DEM (Digital Elevation Model) derived from the last returns of LIDAR. Using maximum likelihood classification method, three bands of multispectral images, LIDAR vegetation height image, and intensity image were employed for land cover classification. Overall accuracy of classification using all the five images was improved to 85.6% about 10% higher than that using only the three bands of multispectral images. The classification accuracy of rural land cover map using multispectral images and LIDAR images, was improved with clear difference between heights of different crops and between heights of crop and tree by LIDAR data and use of LIDAR intensity for land cover classification.

• Korean Journal of Environmental Agriculture
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• v.26 no.4
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• pp.300-305
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• 2007

Soil erosion is one of the most serious problems in alpine upland in Korea. Soil fertility has continuously decreased due to serious soil erosion. To increase soil fertility, new sources of organic matter should be inputted. Therefore, the objectives of this research were to select winter cover crop as new sources of organic matter and to investigate the effect of winter cover crop on soil property changes, major crop productivity (Chinese cabbage, potato) production in highland, and disease occurrence with different cropping systems. Among 17 candidates for winter coverage crop, rye was most suitable due to it's soil covering rate, and over-wintering rate. The optimum sowing period for rye ranged from late August to late September. Soil porosity and organic matter content increased with rye cultivation. Rye cultivation during winter increased amounts of crop (both Chinese cabbage and potato) productivity up to 8%. There was little difference on amount of crop productivity depending on cropping systems such as monoculture (Chinese cabbage or potato) and Chinese cabbage-potato rotation.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.6_1
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• pp.583-590
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• 2012

This study proposes fusion image matching method according to land cover property to generate a detailed DEM using the high resolution IKONOS-2 stereo pair. A classified image, consists of building, crop-land, forest, road and shadow-water, is produced by color image with four bands. Edges and points are also extracted from panchromatic image. Matching is performed by the cross-correlation computing after five classes are automatically selected in a reference image. In each of building class, crop-land class, forest class and road class, matching was performed by the grid and edge, only grid, only grid, grid and point, respectively. Shadow-water class was excepted in the matching because this area causes excessive error of the DEM. As the results, edge line, building and residential area could be expressed more dense than DEM by the conventional method.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.4
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• pp.308-315
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• 2003

A field experiment was conducted to investigate the performance of three legume species in a zero-tillage, non-fertilized rice field in a temperate zone. Before the experiment for 5 years, from 1995 to 1999, plant growth patterns of three legume species grown as over-wintering (October-May) cover crops on a paddy field were maintained to study N balance and $\textrm{N}_2$ fixation. Decrease in plant density accelerated from after winter to flowering from 1,090, 320, and 5 to 732, 232, and 6 plants $\textrm{m}^{-2}$ in Chinese milk vetch (CMV), white clover (WC), and hairy vetch (HV), respectively. Total dry weights of plants above-ground level were 0.05, 0.11, and 2.43 g $\textrm{plant}^{-1}$. in WC, CMV and HV respectively but steeply increased at ripening up to 0.77, 2.33, and 26 g $\textrm{plant}^{-1}$. The root dry weight of HV and CMV rapidly increased while in WC, root dry weight increased slightly towards flowering. The highest nodule numbers were recorded in CMV to April thereafter WC produced the highest. Nodule size was distributed within 7mm in CMV but it was larger in HV varying from 1 to 10mm. Shoot N (g $\textrm{m}^{-2}$) greatly increased from over-wintering to flowering in CMV, HV and WC and it ranged from 1.66, 0.5 and 1.92 to 12.6, 3.1 and 13.02 g $\textrm{m}^{-2}$, respectively. After wintering, the initial shoot N content (%) was more in CMV. Root N content (%) was constant or slightly decreased in HV and WC. Soil total N in the control plot (clean fallow) was the highest on Mar. 2 then decreased rapidly to flowering. Soil N content was constant in HV plots whereas it was low in WC plots for the entire growth period except just after winter. Maximum nitrogenase activities were 9, 37.8, and 131 mol $\textrm{C}_2\textrm{H}_4$ $\textrm{plant}^{-1}$ $\textrm{hour}^{-1}$. in CMV, HV, and WC, respectively. Nitrogenase activity showed a direct correlation with nodule number, size and fresh weight. As a cover crop preceding a rice crop, CMV is more suited to colder regions due to its earlier ripening characteristics. Hairy vetch and WC are recommended for regions with a mild winter and a long summer owing to their late ripening and great N fixation activity.

• Asian Journal of Turfgrass Science
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• v.9 no.2
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• pp.101-107
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• 1995

A Zoysia japonica and Miscanthus sinensis grasslands of north-west side on Mt. Kwanak were investigated The most important species in this area were Zoysia japonica and Miscanthus sinensis These two species contributed greatly to the standing crops of live material, which were in excess of 598. 4g /$m^2$ and 698. 7g /$m^2$ during the growing season, respectively. This value would he ucreased if the production of the moss and algal mats which cover the soil surface during the growing season was included. The productive structures of the Zoysia japonica and Mliscanthus si nen sis grasslands were short and long height types of the grasslands, respectively. Key words: Standing crop, Production structure.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.1
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• pp.49-54
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• 1999

An experiment was carried out using pots to investigate the effects of Chinese milk vetch on the seedling establishment and growth in rice. Four irrigations with five-day intervals and three different levels of vetch straw were investigated. Significantly higher panicle numbers were obtained in vetch-treated pots. Vetch levels were non-treatment as checks, vetch with top removed, root plus shoot 7.5 ton/ha, and root plus shoot 3.0 ton/ha. The time for complete degradation of vetch straws was reduced from 10 days to 5 days as submerged time was delayed, and was affected by the amount of mulched vetch straws. As the mulched vetch amount increased, the time for a complete degradation was extended from 4 days to 12 days. Grain yield and its components were significantly affected by irrigation time and mulched vetch amount. Effectively controlled, lowered reduction damage from the degrading vetch straw, irrigation date and vetch amount were the most important factors for the improving of seedling establishment in direct-sown rice.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.4
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• pp.270-275
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• 2013

Hairy vetch can fix nitrogen from the atmosphere as a leguminous cover crop. This research was carried out to determine optimum seeding method of hairy vetch and application effect in paddy. Field experiment was conducted at Sinheung series (fine loamy, mixed, nonacid, mesic family of Fluvaquentic Endoaquepts) from Sep. 2011 to Oct. 2012 at the National Institute of Crop Science (NICS), RDA, Suwon, Gyeonggi province, Korea. Hairy vetch used in the study was 'Cheongpyungbora', developed by National Institute of Crop Science. Seeding methods of hairy vetch consisted of Broadcasting Before Rice Harvesting (BBRH), Partial Tillage Seeding (PTS), Minimum Tillage Seeding (MTS), No Tillage Seeding (NTS), and Drill Seeding (DS). Both MTS and NTS showed the highest biomass among the seeding methods. The rice yield of MTS and NTS significantly increased compared to conventional fertilization (CF). Also soil properties including organic matter and bulk density were improved by incorporation of hairy vetch. Therefore, we suggested that MTS and NTS could be used to produce hairy vetch and rice in paddy.

• Korean Journal of Medicinal Crop Science
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• v.28 no.4
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• pp.298-309
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• 2020

Background: Safflower (Carthamus tinctorius L.) is a useful medicinal and oil crop in Korea. However, when safflower is cultivated, the flowering period overlaps with the rainy season, and seed maturation is poor. Therefore, this study aimed to use basic research data to develop superior varieties using agronomic characteristics and crossing method. Methods and Results: A total of 34 safflower germplasms were sown and their agronomic characteristics were investigated. Based on these investigations, the cultivar 'ui-san-hong-hwa' was selected as the mother plant, and 'Myanmar safflower' (Hsu Pan) was selected as the father plant. In addition, we developed a floret-protecting cap to cover florets after emasculation during the artificial crossing. When florets were protected by the cap, the seed setting rate increased in comparison to that in the non-covered florets. Conclusions: Agronomic characteristics can contribute to developing suitable varieties. The results suggest that the protection cap will be helpful in breeding without the floral organ drying. This study contributes an efficient breeding method to develop new safflower varieties.

• 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.