• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.2
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• pp.128-133
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• 1993

This experiment was carried out to evaluate the germination characteristics of Korean red rice seeds. Ten lines of the long grain and ten lines of the short grain Korean red rices were tested for dormancy, shoot emergence rate at different water and soil depth. Both the long and short grain type seeds of Korean red rice germinated over than 99% immediately after harvest, so that no dormancy was observed in the Korean red rices. Shoot emergence rate of the long grain red rices at 7cm of water depth and that of the short grain red rices at 11cm were 83.3% and 83.5% respectively, while those of the indica check Samgangbyeo and japonica check Seomjinbyeo were 0%. Shoot emergence rates of the long and short grain red rices at 7cm of soil depth were 71.1% and 73.9% respectively, while those of the check varieties Samgangbyeo and Seomjinbyeo were 40.0% and 28.0% respectively. Thus, the Korean red rices were expected to be useful germplasm source for direct seeding.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.458-462
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• 2013

A drainage ditch is normally a component of drainage networks in farming systems to remove surplus water, but at the same time, it may act as a major conduit of agricultural nonpoint source pollutions such as sediment, nitrogen, phosphorus, and so on. The hybrid turbidity reduction system using biodegradable check dam and synthetic polymer was developed in this study to manage pollutant discharge from agricultural farmlands during rainfall events and/or irrigation periods. The performance of this hybrid system was assessed using a laboratory open channel sized in 10m-length and 0.2m-width. Various check dams using agricultural byproducts (e.g., rice straw, rice husks, coconut fiber and a mixture of rice husks and coconut fiber) were tested and additional physical factors (e.g., channel slope, flowrate, PAM dosage, turbidity level, etc.) affecting on turbidity reduction were applied to assess their performance. A series of lab experiments clearly showed that the hybrid turbidity reduction system could play a significant role as a supplementary of Best Management Practice (BMP). Moreover, the findings of this study could facilitate to develop an advanced BMP for minimizing nonpoint source pollution from agricultural farmlands and ultimately to achieve the sustainable agriculture.

• Korean Journal of Environment and Ecology
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• v.29 no.2
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• pp.279-291
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• 2015

This study analyzed the growth characteristics of multi-layer planted trees through their growth analysis and attempted to present a management strategy. The subject of research is the Citizen's Forest Area of Seoul Forest Park located in Seoul City. Field surveys were conducted three times over eight years from 2005 when the Seoul Forest Park was created through 2013. Labels were attached to all trees in the target area, and their species, height and DBH were investigated. To identify the growth differences by trees in each area, a detailed tree location map was drawn up for use in the analysis. To check soil health, soil organic matter, soil pH and soil microbial activities were analyzed. It turned out that the growth of the multi-layer planted trees in the target area of research was higher than that of the trees in existing urban parks, and that it was similar to that of trees in natural forests. Through a field survey in the area with a remarkably low growth, high-density planting problem, soil was found to have excess-moisture and there was the problem of Pueraria lobata covering. As a result of the analysis of the soil, it was found that its organic content in the soil was lower; soil pH was higher; and microbial activities in the soil were lower when compared to that of natural forests.

• Earthquakes and Structures
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• v.3 no.3_4
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• pp.549-561
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• 2012

Many building foundations are embedded, however it is not easy to compact the backfill around the foundation especially for the deeply embedded ones. The soil condition around the embedded foundation may affect the seismic response of a building due to the weak contact between the soil and the foundation. In this paper, the response accelerations in the short-period range and at the period of 1 second (in the long-period range) for a seismic design spectrum specified in the IBC design code were compared considering perfect and poor backfills to investigate the effect of backfill compaction around the embedded foundation. An in-house finite-element software (P3DASS) which has the capability of horizontal pseudo-3D seismic analysis with linear soil layers was used to perform the seismic analyses of the structure-soil system with an embedded foundation. Seismic analyses were carried out with 7 bedrock earthquake records provided by the Pacific Earthquake Engineering Research Center (PEER), scaling the peak ground accelerations to 0.1 g. The results indicate that the poor backfill is not detrimental to the seismic response of a building, if the foundation is not embedded deeply in the soft soil. However, it is necessary to perform the seismic analysis for the structure-soil system embedded deeply in the soft soil to check the seismic resonance due to the soft soil layer beneath the foundation, and to compact the backfill as well as possible.

• International Journal of Computer Science & Network Security
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• v.23 no.4
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• pp.146-150
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• 2023

In areas where water is scarce, water management is critical. This has an impact on agriculture, as a significant amount of water is used for that purpose. Electronic measurement equipment are essential for regulating and storing soil data. As a result, research has been conducted to manage water usage in the irrigation process. Many equipment for managing soil fertility systems are extremely expensive, making this type of system unaffordable for small farmers. These soil fertility control systems are simple to implement because to recent improvements in IoT technology. The goal of this project is to develop a new methodology for smart irrigation systems. The parameters required to maintain water amount and quality, soil properties, and weather conditions are determined by this IoT-based Smart irrigation System. The system also assists in sending warning signals to the consumer when an error occurs in determining the percentage of moisture in the soil specified for the crop, as well as an alert message when the fertility of the soil changes, since many workers, particularly in big projects, find it extremely difficult to check the soil on a daily basis and operate agricultural devices such as sprinkler and soil fertilizing devices.

• The Korean Journal of Soil Zoology
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• v.10 no.1_2
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• pp.42-54
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• 2005

Herein, 20 species of the ground beetles are reported from Jejudo. Of these, 5 species, Agonum mandli $Jedli{\check{c}}ka$, 1933, Agonum subfuliginosum Habu, 1978, Cymindis kuznevowi Sundukov, 2001, Dicheirotrichus punctatellus (Reitter, 1894), and Harpalus rubripes(Duftschmid. 1812) are listed for the first time from the Korean Peninsula.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.14
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• pp.147-157
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• 1973

I. The effect of excessive soil moisture(at the time of germination) on germination of barley and crop damage of herbicides was investigated. Machete(Butachlor) and TOK(Nitrofen) were treated, respectively, at the rate of 150g ai/10a on each pot whose different soil moisture content was controlled by suppling 30, 40, 50 and 60ml of water per 100gr of air-dried soil, respectively. The results are summarized as follows: 1. Excessive soil moisture beyond field moisture capacity caused great inhibition, from 20 to 100%, of the germination of barley even at untreated pots(check pots). Also, further development of root and growth of barley were greatly inhibited even though the seeds germinated. 2. The same tendency in inhibition of germination and growth as at untreated pots was observed at treated pots, too. As a whole, however, the damage were heavier at treated pots. II. Wanju naked spring barley was seeded on four different soils and covered with soil to a depth of 1 em, and then Machete, TOK, Saturn and HE-314 were treated at the rate of 180, 150 and 200, 150, and 250g ai/10a, respectively, and the effect of soil texture on crop damage of the herbicides was investigated. The results are summarized as follows: 1. Machete(emulsion and granule, at 180g ai/10a) The degree of crop damage was quite different from one soil texture to another: while almost no crop damage was observed on a clay loam soil regardless of the type of formulation, the damage became heavier as the soil texture became sandier as sandy clay loam, volcanic ash loam and sandy loam, and great inhibition of growth was observed on sandy loam soil. In general heavier damage was caused by the application of emulsion than by granular formulation. 2. TOK(Wettable powder, at 150, 250g ai/l0a) Almost the same tendency as in the application of Machete was observed, and the damage became heavier as the application rate increased. 3. Saturn(at l50g ai/l0a) No great difference in crop damage among soil textures was observed. 4. HE-3l4(at 250g ai/l0a) Almost no difference in crop damage among soil textures was observed at this rate of 250g ai/l0a. III. To study a difference of crop damage on soil covering depth(4 levels), 9 herbicides(TOK, MO, HE-3l4, Machete, Saturn, Simetryne, Simazine, Gesaran, Lorox) were treated on the pots with two different soils, and the effect of soil covering depth on crop damage of the herbicides was investigated. The results obtained in this experiment are summarized as follows: Light Clay Soil 1. The growth of barley in relation to depth of soil covering at check pots followed the order vigorous to weak; lcm>1.5cm>0.5cm>0cm. And in case of 0 and 0.5cm covering the growth of barley was very poor. 2. The damage at 0 and 0.5cm covering at treated pots was very severe, but Saturn, Machete, MO and TOK at 100 to l50g ai/l0a, respectively and He-3l4 at 250 to 375g ai/l0a were relatively safe to barley at the depths of lcm and above. 3. Simazine, Lorox and Simetryne caused slight damage even at 1.5cm covering. Sandy Loam Soil The growth of barley in relation to depth of soil covering at untreated pots followed the order, from vigorous to weak; 1.5cm 0.5cm 3cm 5cm. While MO was safe to barley at 1.5cm covering, for other chemicals more than 3cm covering was require for safe use. Machete and Saturn at 100g ai/l0a, and HE-3l4 at 250g ai/l0a was relatively safe at more than 3cm covering. Simazine, Lorox, Simetryne and Gesaran were unsafe on sandy soil regardless of covering depth.

• Research in Plant Disease
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• v.15 no.2
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• pp.106-111
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• 2009

Before transplanting Chinese cabbage seedlings, two kinds of eggshell powder were blended into the soil of cabbage field where the club root pathogen, Plasmodiophora brassicae, was infested. The incidence of clubroot disease, the shoot and root growth of cabbages, and soil pH were examined four times at 10 to 13 days interval from transplanting Chinese cabbage. As results, the cabbages treated with eggshell powder without membrane showed the fastest growth in above ground part, and the lowest disease index for clubroot disease. The cabbages treated with eggshell powder with membrane showed better growth than the cabbages of non-treated check, but lower growth than those treated with eggshell powder without membrane. Soil pH started to increase from 3 weeks after soil blending of eggshell powder, and it reached to above 8.0. However, the soil pH of non-treated check stayed at around 6.8. In the experiment to compare the effect of eggshell powder with other calcium compounds, soil-blending of $CaCO_3$ resulted the lowest disease incidence of 1.7 and the registered fungicide, 'flusulfamide', and the resistant variety 'CR Green cabbage' followed with the incidence of 1.9. Cabbages of non-treated check scored the highest disease incidence, 3.4, and that of eggshell powder without membrane was as high as 2.7. However, the growth of Chinese cabbage showed the different pattern to the disease incidence. Chinese cabbages treated with eggshell without membrane recorded the highest average growth, around 2.1 kg. On the other hand, the average growth of CR Green Chinese cabbage was about 2.0 kg, that of flusulfamide-treatment plot was 1.7, and that of non-treated check was as low as 1.3 kg. Soil blending of eggshell powder without membrane did not inhibit the development of clubroot, but increased the growth of cabbage to a great extent. Therefore, it was confirmed that soil blending of eggshell powder before transplanting makes the Chinese cabbage culture possible even in the field infested with club root pathogen.

• Korean Journal of Weed Science
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• v.6 no.1
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• pp.76-84
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• 1986

All combinations of oxyfluorfen in 5 dosages and glyphosate in 4 dosages were used to assess the onto-drifting pattern of herbicide inactivation in three different type, such as check soil ($O^-M^-$), organic soil ($O^+M^-$), and micro-organism soil ($O^+M^+$). The plant used for bioassay was rape-hybrid. From the results, it was recognized that the herbicide inactivation is strongly achieved in order of $O^+M^+$ > $O^+M^-$ > $O^-M^-$ soil. Also, the inactivation of oxyfluorfen in soil tended to depend rather on soil microorganisms than organic matter, and to be promoted earlier by paraquat mixture than by that of glyphosate. Average 50 and 95% inactivated time (in days) of herbicides were getting shorten in order of $O^+M^+$, $O^+M^-$, $O^-M^-$, rather prolonged in mixture than in oxyfluorfen single treatment, and rather prolonged in high dose than in low dose, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.1
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• pp.1-6
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• 1999

To find the latent effect of paper mill sludges (PMS) with and without alum, and alum paper mill sludge compost(PMSC) on aluminum toxicity of crops, the pH buffer capacity and the acidification resistance index (ARI) for PMSs and PMSC were investigated, comparing to upland soil. Buffer capacities of PMS with and without alum, and PMSC were significantly higher than $2.5cmol^+kg^{-1}$ of check soil as 137, 250, and $147cmol^+kg^{-1}$, respectively. Owing to such high buffer capacity of PMS and PMSC, they showed to be well-resisted to acidification.