• Journal of Microbiology and Biotechnology
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• v.27 no.3
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• pp.524-534
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• 2017

The development and utilization of crop straw biogas resources can effectively alleviate the shortage of energy, environmental pollution, and other issues. This study performed a continuous batch test at $35^{\circ}C$ to assess the methane production potential and volatile organic acid contents using the modified Gompertz equation. Illumina MiSeq platform sequencing, which is a sequencing method based on sequencing-by-synthesis, was used to compare the archaeal community diversity, and denaturing gradient gel electrophoresis (DGGE) was used to analyze the bacterial community diversity in rice straw, dry maize straw, silage maize straw, and tobacco straw. The results showed that cumulative gas production values for silage maize straw, rice straw, dry maize straw, and tobacco straw were 4,870, 4,032.5, 3,907.5, and $3,628.3ml/g{\cdot}VS$, respectively, after 24 days. Maximum daily gas production values of silage maize straw and rice straw were 1,025 and $904.17ml/g{\cdot}VS$, respectively, followed by tobacco straw and dry maize straw. The methane content of all four kinds of straws was > 60%, particularly that of silage maize straw, which peaked at 67.3%. Biogas production from the four kinds of straw was in the order silage maize straw > rice straw > dry maize straw > tobacco straw, and the values were 1,166.7, 1,048.4, 890, and $637.4ml/g{\cdot}VS$, respectively. The microbial community analysis showed that metabolism was mainly carried out by acetate-utilizing methanogens, and that Methanosarcina was the dominant archaeal genus in the four kinds of straw, and the DGGE bands belonged to the phyla Firmicutes, Bacteroidetes, and Chloroflexi. Silage maize is useful for biogas production because it contains four kinds of straw.

• Journal of The Korean Society of Agricultural Engineers
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• v.59 no.2
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• pp.13-18
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• 2017

Farmers seek for high profitability by increasing the best use of land, and the selection of crops is the first and basic way to achieve their goals. When farmers select crops, the climate, price and productivity of crops are usually considered at the first stage. However, a crucial factor is to understand general characteristics of soils where the crops were grown, but many farmers are lacking in detailed knowledge about soils. The purpose of this study is to search and analyses factors based upon related soil and others in decision-making for the selection of crops. In result, the cultivated rate of the top 5 corps in the suitable areas for cultivation (SAC) is only 53 % which shows most farmers are plants their crops in unsuitable sites. To examine factors influencing on the selection of crops except for soils, surveys about their farm characteristic and Korea Soil Information System (KSIS) were conducted. The result of survey shows 20 % of farmers know KSIS. To increase that rate, there were many changes on soil's characteristic, and at the same time, climate conditions should be updated. It can be expected to increase the rate of farmers' utilization of KSIS.

• Journal of Korean Society of Rural Planning
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• v.21 no.2
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• pp.189-199
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• 2015

This study made use of 9 types of utilizing idle farmland deducted from existing research in order to examine cases by type of idle farmland, and selected representative cases by type after analyzing contents of 165 available newspaper articles. Selected Cases were assorted into agricultural use and nonagricultural use, and agricultural use are as followed. (1)Community Service/Farming type is the case of Gimhae city reported on 'Busan Ilbo', (2)High Income/Farming type is the case of cooperative unit of Geumjeong crude drug in Yeongam appeared in 'Newsis', and the case of Omija industry in Mungyeong reported on 'Hankyoreh', (3)Tourism/Landscape/Farming type is the case of rape flowers and buckwheat flowers in Gupo village reported on 'Asia News Agency', (4)Stock Raising/Farming type is the case of growing foraging crops published in 'The Daejeon Ilbo', (5)Weekend farm type is the case of utilizing idle farmlands and creating weekend farm reported on 'Mediawatch', (6)High income/Forest type is creating Mulberry cultivation areas in Hamyang-Gun published in 'Yonhap News', (7)Ecology/Landscape/Forest type is forestation project of idle land reported on 'Newsis', (8)Agricultural Experience Study type is the case of managing agricultural experience study center in Dosun elementary center published in 'Sisajeju' and the case of non-agricultural application case, (9)Ecological Environment type is the case of wetland restoration of idle farmland in Gochang. This study investigated and arranged detailed contents by the literature search and interview investigation according to investigating items such as utilizing area, main agent, purpose, utilizing item, utilizing content, etc. by case. With that, it deducted implications as well as case characteristics, and finally suggested political proposals through the case analysis.

• Korean Journal of Soil Science and Fertilizer
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• v.5 no.2
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• pp.53-57
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• 1972

In order to obtain some informations on the improvement of fertility of poor red yellow soils widely distributed in hilly lands of Korean peninsula, a pot culture study was made with a hill land soil in comparison with a fertile soil commonly used for vegetables. The results are as follows; 1. In addition to the normal application of phosphate, the mixing of a large dose of fused phosphate with whole soil increased the yeild of chinese cabbage remarkably, having the promotion particulary of the available phosphate level in the acidic low fertility soil. At the sometime the mixing seemed to short down the period of soil maturing to fertile for good crop. It is, however, considered that such effect of fused phosphate must also be evaluated economically through a long term experiment. 2. A relatively close relationship between the soil phosphate soluble in dilute acid and chinese cabbage growth was observed.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2008.10a
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• pp.153-161
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• 2008

Agriculture and forest are basis for livelihood in Nepal while both sectors constitute around 40 percent of the national product and over two-thirds of the economically active population is dependent on agriculture. However, radical changes in land use, depletion in crops production and food availability are major threats due to loss of soil fertilityand severe environmental degradation. In this study, we used time series data from 1986/87 to 2005/06 about food crop production and population published by Government of Nepal, Ministry of Agriculture and Cooperatives and Central Bureau of Statistics. Descriptive statistics and ArcGIS were used to assess and map the food security status of Nepalese Terai based on the local food demand and supply system. Food supply to demand ratio(FSDR) was the main idea of assessment. Our results showed that out of 20 districts, only 8 districts were categorised under secured food districts whereas 5 districts were still under food unsecured situation. The analysis further revealed that 7 districts had faced food deficit more than 8-16 times during the last 20 year periods. Data further showed that there was surplus food supply relative to the requirements dictated by FSDR. However, the average FSDR was less than 1.2(less than 20% surplus) exploring fact that most of the districts were not producing sufficient food to cope up the food shock and after 1995 it was relatively stagnant. Our prediction reveals that food supply in Terai even in the future would remain at almost the same level as now, and there will not more than 16-17% surplus by 2021 considering medium vibrant population growth. The findings thus, indicate that Terai may not be a food secure region in the future, even though the region is considered as a food storage house of Nepal. In addition, this paper suggests ways to make future comprehensive case studies more widely comparable in Terai, Nepal.

• Korean Journal of Agricultural Science
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• v.46 no.4
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• pp.791-798
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• 2019

This experiment was conducted to find out the difference between roughage productivity and feed value by using two domestic forage rice cultivars in a mid-west reclaimed rice field in Korea. During the growing period, Na⁺ content in soil showed no significant difference between the two cultivars; however, the K⁺ content in the soil was significantly lower than that in which the Mogwo was grown. The tiller number was 45.5 to 58.8, which was higher than that of Mogyeong, and the leaf number was higher than that of Mogyeong. The dry matter yield per 10 a was 1,338 kg for Moggyang and 1,532 kg for Mogwoo. At the harvest time, the crude protein yield per 10 a produced 108 kg of Mogyang and 170 kg of Mogwoo, and the total digestion nutrient (TDN) yield per 10 a also produced about 617 kg of Mogyang and 880 kg of Mogwoo. To sum up the above results, Mogwo, which has many tiller numbers and leaf numbers, has a high dry matter production, a relatively low neutral detergent fiber (NDF) and acidic detergent fiber (ADF), and a high crude protein yield and TDN yield, and it was better when cultivating the forage rice cultivars in reclaimed land.

• Journal of the Korean Society of Tobacco Science
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• v.2 no.1
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• pp.37-52
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• 1980

Two-year experiment was conducted to investigate the effect of phosphorous, lime, increased compost, and/or boron application on the yield and quality of leaf tobacco growm in the results are summarized as follows; 1) Compared to the conventional treatment, plants grown in the treated plots in the second year showed much better growth and their yield components such as leaf area index and unit leaf weight were much greater. 2) At the end of first year crop, the pH and amount of exchangeable cations in the treated plots reached those in mature soil, but the amount of organic matter and of available phosphorous were still below those of the mature soil. Application of additional compost was more effective in enhancing soil fertility than was additional phosphorous application. 3) The yield of tobacco grown in the second year was 15-20% higher in the treated plots, compared to conventional plot, with high statistical significance. Though the quality of leaf tobacco was not significantly different among treatments, the increase of 3-7% was obtained in the treated plot. The highest total income(yield x price/kg) came from the plot treated with additional compost and phosphorous application (adjusted at 3% level on the basis of phosphorous absorption coefficient), which produced 34% more than the conventional plot.

• Journal of Environmental Science International
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• v.20 no.8
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• pp.977-986
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• 2011

This study analyzed the characteristics of stormwater runoff in the orchard areas and quantitatively estimated effluence of nonpoint source pollutants for the volume of runoff. Two target areas under vine cultivation were each $2,000m^2$ and $1,800m^2$, located in Gyeongju City. Since grape was the only crop on the target area, the characteristics of stormwater runoff at vineyard could be evaluated independently. A total of 51 rainfall events in the vineyard area during two years(2008-2009) was surveyed, and 19 of them became stormwater runoff, with rainfall ranging 16.5 - 79.7 mm and antecedent dry period of 1-13 days. The pollutant runoff loads by volume of stormwater runoff showed BOD ranging 19.5 - 45.3% in 30% of runoff volume. The average pollution discharge rate was 32.4%, indicating small first flush effect of BOD. The range of SS concentrations was 5 - 52.0% in 10% of runoff volume, showing the average 28.7% of discharge rate, about 3 times more than rainfall effluent. TOC and TN appeared to be similar to the results of BOD, the average discharge rate of 30.9% and 30.6% for TOC and TN, respectively, for 30% of stormwater runoff volume. Average discharge rate of COD and TP in the same runoff volume was 35.1% and 36%, respectively, showing comparatively high discharge ratio. As the targeted vineyard area was permeable land, the pollution load ratio against rainfall-runoff volume appeared to be 1:1, implying no strong first flush effect for all the survey items.

• Korean Journal of Plant Resources
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• v.30 no.5
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• pp.549-555
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• 2017

The production of ginseng cultivation is decreasing due to shortage of cultivated land and climate change, so additional methods are needed. Therefore, the physiological and morphological characteristics of finebubble were analyzed by applying them to ginseng cultivation which is the representative crop of Korea. The application of fine bubble water to 2 year old ginseng showed that stem length and leaf were increased, and weight increased as main root increased in root. In particular, it is shown that the weight of roots increases with the increase of leaf size. This is because the total chlorophyll content is high and it is judged to be related to the increase of photosynthesis efficiency. When the results of this study were confirmed, it was confirmed that ginseng cultivation using fine bubbles showed no inhibition of growth of ginseng. According to the results of physiological characteristics and subdividing results, It was confirmed that the growth of about 10% to 15% of the growth was increased and that the growth of ginseng was increased by applying the fine bubble when growing ginseng.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.1
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• pp.147-157
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• 2013

Rice is a main crop and rice field is the most important farmland in Korea. This study was conducted to propose the methodology assessing impact and vulnerability on rice production by climate change at the regional and national level in Korea. We evaluated a vulnerability of rice paddy according to the outbreak of a main disease and pest of a rice plant. As results, Jeju-do, Gyeongsangnam-do, and Jeollanam-do were more vulnerable area than others. In contrast, the southern central region including Gyeonggi-do was less vulnerable than others. The vulnerable index was significantly higher in 2050s (0.5589) than in present (0.3500). This result showed that the vulnerable to the disease and pest enlarge in the future. The adaptive capacity highly contributed to the vulnerability assessment index. The daily maximum temperature of June and the daily average temperature from May to August also contributed the climate exposure index. The area of occurring sheath blight, rice leaf blast and striped rice borer was related to the system sensitivity index. The ability of water supply (readjustment area of arable land per paddy field area) and rice production technique (rice yield per hectare) were the highly contributed variables to the adaption capacity index.