• Journal of Korean Society of Forest Science
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• v.102 no.1
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• pp.66-73
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• 2013

This study was conducted to determine the effects of rice hull cover on seed germination and tray types, soil types, shading conditions for seedling growth of Codonopsis pilosuala. We also examined the feasibility of cultivation of small seedlings transplanted in the Gyeonggi-do area for a month. Under control condition, the seed germination was 8% whereas it dramatically increased to 78% under rice hull cover treatment. Under the different conditions (tray types, soil types, and shading conditions), young seedlings showed the best quality without shading in TKS soil of 50 plug cell tray, with the growth characteristics of plant height (11.9 cm), number of leaves (71), leaf width (3.1 cm), leaf length (2.6 cm), and root length (14.3 cm). Seedling quality was the best without any shading in TKS+perlite, with the physiological characteristics of evaporation (3.9 $mmol{\cdot}m^{-2}s^{-1}$), carbon assimilation (9.1 ${\mu}mol{\cdot}m^{-2}s^{-1}$), and water use efficiency (2.2 ${\mu}mol{\cdot}m^{-2}s^{-1}$). Considering the economical, morphological, physiological and survival rate of the seedlings, it was an ideal method for transplanting seedlings in the field after they have been grown for 30-45 days in TKS and TKS+perlite of 200 plug cell tray in 0% or 30% shaded conditions. As the results of 5 months examination on the possibility to cultivate Codonopsis pilosuala in the Gyeonggi-do area, 88% to 96% of survival rate was observed with normal induced flowers. Therefore, cultivation of Codonopsis pilosuala was possible in the Gyeonggi-do area. While there were symptoms of etiolation and wilting under no shading condition, they did not appear in 30% and 70% shading conditions. Therefore, cultivation of Codonopsis pilosuala is considered to be necessary 30% or 70% shading.

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.2
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• pp.143-151
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• 2010

The impact of climate change on rice plants in Gangwon province was examined by comparing the climatic conditions during the recent 10 years (2000~2009) with those of normal (1971~2000) years, and by evaluating the rice plant responses. The daily mean air temperature increased by $0.5^{\circ}C$ while the daily range decreased by $0.1^{\circ}C$ as compared with the normal years. During the main rice growing period in field (from June to September) precipitation increased from 900 to 1,051mm and sunshine hours decreased from 704 to 619 hours. The respiration consumption effect during the rice growing period increased by 0.07 as a result of increased air temperature and reduced sunshine hours. The optimum heading date (determined by the mean air temperature for 40 days after the heading) was delayed in Chuncheon, Hongcheon, Wonju, and Gangneung compared with the normal. The maximum climatic yield potential based on mean temperature and sunshine hours for 40 days after the rice heading decreased by 94 kg/10a mainly due to the decrease in sunshine. The mean air temperature for 40 days after the rice heading from 1999 to 2009 in Chuncheon, Cheorwon, and Gangneung was generally above $22^{\circ}C$ implying that yield and quality of rice can be reduced. Therefore, it is necessary to delay the heading date by planting mid- to late-maturing varieties or by changing the transplanting date in order to produce high quality rice and to maintain rice productivity. In addition, it is also important to develop or select cultivars suitable to changing climate for each region in Gangwon province.

• Journal of Korean Society of Forest Science
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• v.76 no.4
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• pp.338-347
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• 1987

The research was carried out to investigate the related phenomena, the latent structures and synthetical characteristics in various growth factors of Phyllostachys bambusoides Sieb. et Zucc. growing at Damyang gun, Chollanamdo, using multivariate analysis. 1. By synthetical characteristics in canonical correlation between height-growth factor group and diameter-growth factor group, the former was determined by the culm height ($x_1$), and the latter by the. diameter of the largest internode($x_7$). And for those between quantitative growth factor group and qualitative growth factor group, the former was determined by the surface area($x_{10}$), and the latter by the diameter of the largest internode ($x_7$). 2. The ten growth factors of bamboo culm were simplified by two principal components on the basis of accumulated proportion aimed at 90%. The first principal component($Z_1$) as a "size factor" showed high correlation with growth factors except eye-height diameter($x_5$). The second principal component($Z_2$) as a "shape factor" showed high correlation only with $x_5$. 3. The bamboo culm, and the latent phenomenon between their growth factors could be determined by two common factors showing high communality(94.16%). The ten growth factors can be grouped into two attribute factors: quantity and quality. 4. The bamboo culms can be classified into five types: total, volume, shape-quality, inferior and middle.

• Korean Journal of Ecology and Environment
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• v.52 no.3
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• pp.245-265
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• 2019

Biotope, which represents the characteristic habitats of living organisms, need to be identified as essential for the efficient creation and sustainable management of urban ecosystems. This study was carried out to provide the basic information for ecological urban planning by analyzing types and attributes of the biotop established throughout the whole area of the Pohang city, a representative industrial city in Korea. The biotop established in Pohang city is composed of 12 types including forests (coniferous, deciduous, and mixed forests), agricultural fields (rice paddy and upland field), green facilities, river, reservoir, bare ground, residential area, public facilities, commercial area, industrial area, roads, and schools. As a result of analyzing the properties according to biotop types, industrial, commercial and residential areas, which represent urban areas, was dominated by introduced vegetation. Moreover the introduced vegetation is usually composed of exotic plants or modified forms for landscape architecture and horticulture rather than native plants, which reflects ecological property of both region and site. As the distance from the urban center increases, the agricultural field showed a form of typical farmland, whereas the closer it is, the more form of greenhouse farming. Natural green spaces were divided into riparian vegetation established along the stream and forest vegetation. Forest vegetation is consisted of secondary forests (seven communities) and plantations (three communities). The urban landscape of Pohang city is dominated by the industrial area. Among them, the steel industry, which occurs large amounts of heat pollution and carbon dioxide, occupies a large proportion. On the other hand, green space is very insufficient in quantity and inferior in quality. This study proposed several restoration plans and further, a green network, which ties the existing green spaces and the green space to be restored as a strategy to improve the environmental quality in this area.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.2
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• pp.61-70
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• 2023

In order to select high-quality winter cereal crops with high yield and to increase self-sufficiency rate of forage, their growth, yield, and feeding value of several cereal crops cultivated in winter were investigated in the paddy field of the southern region. Four wheat cultivars and green barley headed in early and mid-April, while oat and Italian ryegrass headed in early May. Fresh forage yields of wheats, green barley, and oat were significantly higher than that of Italian ryegrass, and dry forage yields of wheats and green barley were significantly higher than those of not only Italian ryegrass but also oat. In particular, the yield of a wheat cultivar 'Cheongwoo' was the highest. Mineral contents of wheat forages, even though low, were in the range 27.8~33.7mg·g^-1 DW suitable for feeding cattle and young female cows. Crude protein content of a wheat cultivar 'Cheongwoo' was high up to 7.6%, similarly to 7.0% requiring for feeding cattle. Feeding values such as total digestible nutrients (TDN) and relative feed value (RFV) of wheats and green barley were superior to those of oat and Italian ryegrass. In addition, dry matter rates of 4 wheat cultivars and green barley were in the range 30~40%, indicating that wheat cultivars and green barley could be used for various feeding purposes such as green or dried forage, and silage. Based on these results, wheat cultivars including 'Cheongwoo' and green barley could be encouraged to be cultivated in paddy fields, as high-quality winter forage crops with high yield.

• The Journal of Engineering Geology
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• v.23 no.2
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• pp.95-104
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• 2013

This study proposes an efficient management plan for improving the water quality of agricultural reservoirs. Hongdong reservoir is located in an area that includes farmland, forest, residential housing, and livestock farms. The levels of pollutants in Hongdong reservoir were investigated with the aim of improving the water quality in the reservoir. The potential concentrations of total nitrogen (T-N) and total phosphorus (T-P) in Hongdong reservoir were 1.06-3.67 and 0.52-1.12 $g/m^2-d$, respectively. An analysis of leaching characteristics was performed under anaerobic conditions for 72 hours at $20^{\circ}C$. The concentrations of T-P and $PO_4$-P were measured by general leaching for a set period. In the case of T-P, the leaching was measured by irregular leaching due to denitrification of nitrite nitrogen ($NO_2$-N) and nitrate nitrogen ($NO_3$-N). A very small amount of $NH_3$-N on nitrogen ($N_2$) was measured due to the low pH in the column, as a consequence of the anaerobic conditions.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.12
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• pp.641-646
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• 2016

Soil organic matter (SOM) is an important soil component releasing nutrients to the plants and reducing risks of soil contamination to the human and ecosystem. Much attention has been recently paid to SOM investigation and management because SOM holds the most of carbon in the earth and sequestrate carbon as a sink tank. The first objective of the study was to investigate SOM of 495 soil samples taken at the Korea Soil Quality Monitoring Network. Soil samples were collected from 16 regions and 8 land use types. The second objective of the study was to find a relationship between the Tyurin method and loss-on-ignition (LOI) method for SOM. The means of SOM by Tyurin and LOI methods were 1.90 and 2.92 % (w/w), respectively. Land uses such as forest, religious area and park where organic matters continuously supply to normally showed higher SOMs than residential and school areas having sandy soils. A regression equation of the relationship between Tyurin and LOI methods was y(Tyurin) = 0.6257x(LOI) + 0.0602 (P-value < 0.001). The coefficient of determination was $R^2=0.749$, relatively linearly related. Although LOI may result in higher SOMs than the Tyurin method, LOI may be a preference for the SOM investigation if various kinds of land uses and many soil samples should be measured.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.8
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• pp.1381-1384
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• 2004

In order to help the preservation of the cherry tomatoes, antimicrobial paper incorporating grapefruit seed extract and zeolite was applied to packaging fruits. The fruits were packed with a paper bag of 15.5${\times}$24 cm and then stored at 1$0^{\circ}C$. During the storage, weight loss, pH, total acidity, soluble solid content, microbial load and decay were measured as quality indices. Steady weight loss due to the transpiration was observed to slightly increase the solid content during the storage with little difference between the packaging treatments. There were little change in pH and acidity of the stored fruits. The microbial loads of total aerobic bacteria, and yeast/mold counts were significantly suppressed during 10 day storage by the antimicrobial paper packaging, which also contributed to reducing the decayed fruits observed after 15 days.

• Journal of Life Science
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• v.17 no.9 s.89
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• pp.1290-1293
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• 2007

The nutritional composition of fruiting body of Sparassis crispa has been analyzed for medicinal and edible uses. Minerals in S. crispa were found to be as follows; potassium (1,299.44 mg), phosphorus (104.73 mg), sodium (98.21 mg), magnesium (54.86 mg), calcium (8.39 mg), iron (7.61 mg), zinc (6.37 mg), copper (1.31 mg) and manganese (0.63 mg) based on 100 g of mushroom dry weight. In 20 kinds of total amino acids found in S. crispa, sum of glutamic acid and glutamine content was the highest (1,960 mg/l00 g) and sum of aspartic acid and asparagine, tryptophan, leucine and alanine were followed. Concerning free amino acids, glutamic acid, tryptophan, glutamine and aspartic acid were dominant. Among 8 vitamins detected, the vitamin E content was the highest (408.5 mg) based on 100 g of mushroom dry weight, then vitamin C, niacin and pantothenic acid were followed.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.7
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• pp.952-959
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• 2010

This study was conducted to evaluate growth, behavior and carcass traits of fattening Hanwoo (Korean native cattle) steers managed in different group sizes. A total of 48 animals, 6 months of age, were allocated to one of three group sizes and the experiment was conducted from 12 to 30 months of age. Groups were balanced for weight and the group sizes consisted of 4, 8, or 12 steers which were named 4sG, 8sG and 12sG, respectively. When animals were 12 months of age, initial fasted body weight (BW, $304.51{\pm}12.40\;kg$) was measured. All animals were housed at a constant space allowance of $8.82\;m^2$ per animal, and a feeder and drinker were provided per 4 animals. The whole fattening stage was divided into three phases: phase I (from 12 to 18 month of age), phase II (from 19 to 24 month of age), and phase III (from 25 to 30 month of age). Steers managed in 12sG showed low (p<0.05) growth rate and feed conversion rate (FCR) in phase I and phase II when compared to other treatment groups. However, this difference was not observed for the whole fattening phase (p>0.05). Steers managed in 4sG had a thick (p<0.05) ultrasound back fat thickness at 15 and 18 months of age. However, group size had no effect on meat yield and quality traits of area and marbling score. Animals managed in 8sG yielded a better meat grade of "A" than the "B" grade in other treatment group sizes. Lean color, fat color, firmness and maturity scores did not differ among group sizes. Hanwoo steers housed under 12sG spent less time on eating concentrate, relevant higher eating rate, less frequency of allogrooming, and more time on walking (p<0.05). It could be concluded that a large group size retarded growth rate and back fat thickness in the fattening stage, which was mainly focused on 15 and 18 months of age.