• Journal of Korean Society of Forest Science
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• v.85 no.4
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• pp.634-646
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• 1996

This study was carried out to reveal the forest land effect on water purification in mountainous watersheds. Rainfall, throughfall, stemflow, soil and stream water were monitored by pH, electrical conductivity(EC), and dissolved oxygen(DO) in Daehan-Ri and Parkdal-Ri catchments. The results were summarized as follows; 1. Rainfall pH values of Parkdal-Ri and Daehan-Ri were 7.6 and 6.4, respectively. 2. Comparing stemflow and throughfall of Pinus densiflora with Pinus rigida, the pH values of Pinus densiflora were 4.32 and 4.22 and the pH of Pinus rigida were 3.34 and 4.81, respectively. The EC values of Pinus densiflora were $119.7{\mu}S/cm$ and $96.8{\mu}S/cm$ and EC of Pinus rigida were $230.0{\mu}S/cm$ and $82.0{\mu}S/cm$. 3. All pH values were decreased as the streamflow increased except long-term runoff in Daehan-Ri. The EC values also were increased as the streamflow increased, but EC of short-term runoff in Daehan-Ri was gradually decreased as the streamflow increased due to entrance of throughfall which has high EC values at the beginning of rainfall events. The DO concentrations of all experimental plots were elevated as the streamflow increased, because reaeration occurs at the surface of the stream as the increased discharge make turbulence. 4. pH of Stemflow and throughfall in Pinus densiflora were lower than in Quercus acutissima, but EC values were higher in Pinus densiflora. 5. Water purification was mostly influenced by forest soil in forest hydrological processes. 6. Stemflow and throughfall were more influenced by dry deposition and organic acid in crown and bark than those of wet deposition. During the stemflow and throughfall passed forest soil, these acidic stemflow and throughfall were neutralized, and stream water quality was neutral or slightly alkaline.

• The Korean Journal of Ecology
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• v.26 no.4
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• pp.189-197
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• 2003

Properties of seed production in Corydalis, spring ephemeral, group were studied during two years at Namhansansung area. Corydalis´ flower was out in the early April and its seed dispersed in the early May. The period of total seed production was 30 days. The decrease rate of sex organs was the highest between deflowering time and early fruiting time. The numbers of flower and seed per plant were in the range of 1∼13 and 0∼76, respectively. And the number of seed per fruit was from zero to twenty. In a plant, seed production was the most (11.8 seeds) in the lowest fruit and conspicuously decreased along the upward fruit. In the same plant, seed production was various by each year. The plants of small tuber size produced more seeds and those of large tuber size produced fewer seeds in the next year than this year. In the early growth season, the flowering plants/total plants rate increased in proportion to plant size (tuber volume), the rate of the smallest size class (<100 ㎣) was in the range of 5.0%(1999)∼5.4%(2000), those over the 600 ㎣ size classes were 100%. The number of flower per plant at the same size class were higher in 2000 than in 1999. Especially, at the size class of 900 ㎣≤, the numbers of flower per plant were 13.2 in 2000 and 6.5 in 1999. In the late growth season, the flowering plants/total plants rates were 13.3%in the smallest size class (<100 ㎣)and 100% over the 500 ㎣ size classes. Therefore, the flowering plants/total plants rates along the size classes were higher in the late growth season than in the early one. The bumer of fruit or seed per plant increased in proportion to the volume and dry weight of tuber, there was not significant and varied along each plant in the same size class. The number of fruit or seed per plant conspicuously increased in proportion to the leaf area. Therefore, it was thought that seed production was related to photosynthetic ability during growth season.

• Journal of Korean Society of Forest Science
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• v.38 no.1
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• pp.13-18
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• 1978

In this study, enzymatic hydrolysis of the holocellulose from Alnus hirsuta (Spach) Rupr. (8-14 yr's) was investigated using crude cellulase preparations of Trichoderma viride Pers. ex. Fr. SANK 16374. And conducted on the optimum condition of the treated substrate for saccharification. A strain of Trichoderma viride Pers. ex. Fr. SANK 16374 was found to be highly efficient for the cellulase productivity, especially in the submerged culture process. The culture medium used in this experiment was prepared from an extract of wheat bran consisting also of $KH_2PO_410$, $(NH_4)_2$ $SO_4$ 3, $NaNO_3$ 3, and $MgSO_4$ $7H_2O$ 0.5g/l. Cellulose powder (Toyo filter paper, 60 mesh) was found to be an importent factar for inducing the cellulase formation. And the cellulase produced in the culture fluid was salted out quantitatively by the use of ammonium sulfate (Fig. 1) Reducing sugar was determined by the Dinitrosalicylic acid (DNS) method, using reagents prepared according to the method of Sumner (1925). The results obtained were summerized as follows; 1. The method of delignification were treated by the Peracetic acid (PA) method, according to the method of Toyama (1970). The yield of holocellulose were decreased in accordance with increasing concentration of Peracetic acid solution; delignification of Alnus hirsuta Rupr. with 20% Peracetic acid was satisfied for 48 hours and 40%~60% peracetic acid was satisfied for 24 hrs: 2. The substrate (holocellulose) was changed easely into fine powder with enzymatic hydrolysis and cellulase exhibits optimum activity on the reducing sugar formation from substrate at the range of 60-100 mesh. 3. The reducing sugar formation increased in accordance with increasing dry temperature on holocellulose substrate was found to be $190{\pm}5^{\circ}C$. 4. The optimal heat treated time of holocellulose substrate was found to be 45 min. for the reducing sugar formation showed the best products. The reducing sugar formation did not show statisticaly significent diflerences at 5% levels by heat treated time for 45 min. and 60 min.

• Journal of Bio-Environment Control
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• v.9 no.2
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• pp.85-93
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• 2000

This study was carried out to investigate the effects of several substrates and ratio of NO3--N to NH4--N in nutrient solution on growth, yield and mineral uptake of sweet pepper(Capsicum annuum L.) in bag culture. The content of minerals such as P, K, Ca and Mg showed difference in concentration among media: P and Mg were the highest in vermiculite in vermiculti+rice hull, K in perlite+vermiculite and Ca in perlite+peatmoss; with the lowest in the single perlite medium respectively, Ca of mineral made fairly higest level in concentration compared with the others in all of the media. The concentration of mineral content was lower in the ratio of 8:2 than that of 10:0. Admitting that the pH made difference depending on the kind of substrates and ratios of NO3--N to NH4--N. The pH of 10:0 ratio in all the substrates was higher and more stable than that of 8:2. The range of EC in all the substrates showed from 1.78ds·m-1 to 2.10 ds·m-1, which was optimum range for growth of sweet pepper, and range of EC is larger in 8:2 ratio than that in 10:0 ratio. Plant height and stem diameter were nothing to do with the kind of substrates, but leaf area was the largest at vermiculite+rice hull of the 8:2 ratio, fresh and dry weights were heavier at peatmoss+carbonized rice hull, but were the lightest at perlite. All indexes related to the growth which had something to do with the kind of substrates higher in 8:2 ratio than those in 10:0 ratio. The number of fruit and fresh weight related to the ratio of the 8:2 were the highest as 17.5 at vermiculite+rice hull with 1,588g of fresh weight, while the yield from perlite was the lowest. The number of fruit was the highest as 16.4 at virmiculite+rice hull, yield was the higest as 1,394a at perlite+ peatmoss. The yield of 8:2 ratio at all substrates was higher than that of 10:0 ratio. Of the mineral content related to the plant part, K+ and Mg2+ were higher in concentration at leaf; Ca2+ were higher at root; PO4- was higher at stem and fruit; The content of mineral showed no difference between the ratio of the 8:2 and the ratio of the 10:0 with no regrading to the difference of mineral content among substrates; and K+, Ca2+, and Mg2+ uptake of sweet pepper were higher at 10:0 ratio than that of 8:2; 2while PO4- uptake of sweet pepper was lower at 10:0 ratio than that of 8:2 ratio.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.371-380
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• 2018

Aim of this study was to investigate the effects of different nutrient solutions and various light qualities generated by LED on the growth and glucosinolates contents of watercress (Nasturtium officinale) grown under hydroponics for 3 weeks. The seeds of watercress were sown on crushed rockwool media and raised them for two weeks. They were transplanted in a semi-DFT (deep flow technique) hydroponics system. A controlled-environment room was maintained at $20{\pm}1^{\circ}C$ and $16{\pm}1^{\circ}C$ temperatures and $65{\pm}10%$ and $75{\pm}10%$ relative humidity (day and night, respectively), with a provided photosynthetic photon flux density (PPFD) of $180{\pm}10{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and a photoperiod of 16/8h. To find out the best kinds of nutrient solutions for growing watercress, Otsuka House 1A (OTS), Horticultural Experiment Station in Korea (HES), and Netherland's Proefstaion voor Bloemisterij en Gasgroente (PBG) were adapted with initial EC of $1.0-1.3dS{\cdot}m^{-1}$ and pH of 6.2, irradiating PPFD with fluorescent lamps (Ex-1). Either monochromatic (W10 and R10) or mixed LEDs (R5B1, R3B1, R2B1G1, and W2B1G1) were irradiated with a differing ratio of each LED's PPFD to understanding light quality on the growth and glucosinolates contents of watercress (Ex-2). Although significant difference in the shoot growth of watercress was not found among three nutrient solutions treatments, but the root fresh weight increased by 13.7% and 55.1% in PBG and OTS compared to HES, respectively. OTS increased the gluconasturtiin content by 96% and 65% compared to PBG and HES. Compared with the white light (W10), the red light (R10) showed a 101.3% increase in the shoot length of watercress. Increasing blue light portion positively affected plant growth. The content of total glucosinolates in watercress was increased by 144.5% and 70% per unit dry weight in R3B1 treatment compared with R2B1G1 and W10 treatments, respectively. The growth and total glucosinolates contents of the watercress were highest under R3B1 among six light qualities.

• The Journal of Natural Sciences
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• v.14 no.1
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• pp.139-149
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• 2004

It was aimed to find out an efficient method of drying hot pepper, of which powder is used as one of the main ingredients in Korean dish preparation including Kimchi. Before sun or heat drying fruits harvested were horizontally cut into three pieces punched with an auger of 4 mm in diameter, or used as the whole fruit. Various drying methods were used including sun drying, drying under a plastic house, sun drying after heat drying for 5 hours at $70^{\circ}C$, $80^{\circ}C$, or $90^{\circ}C$, heat drying only at $50^{\circ}C$, $60^{\circ}C$, or $70^{\circ}C$, and changing temperature of $70^{\circ}C$, $5hours+60^{\circ}C$ until coplete dry, $80^{\circ}C+60^{\circ}C$, or $90^{\circ}C+60^{\circ}C$. The results are summarized as follows. With sun drying of the whole fruit, in required about 10days to reach the satisfactory level of dryness as indicated by its moisture content of below 10% in general. In case of heat drying combined with sun drying, it required 5 to 7 days. For cut fruits, it required 1 or 2 days less than for whole or pinholed fruits until drying. Under heat of alternation temperature drying, cut fruits also dried 15-20 hours earlier compared with whole of pinholed fruits. There were not significant differences for the recovery rate of the fruit with various drying methods. The occurrence of white fruits, which are caused by one of physiological disorders during drying, and rotten fruits was reduced with the cut fruit drying. The damages were very high with the PE house drying, but very little with the heat drying.

• Korean Journal of Environment and Ecology
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• v.27 no.1
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• pp.99-112
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• 2013

This study aims to show the changes of characteristics of vegetation structure for 20 years(1991~2010) in Naejangsan National Park. As a result of analysis of actual vegetation, the mixed community of Quercus variabilis and Quercus serrata was distributed with 56.1%, and Q. variabilis community showed in southern steep slope with 17.6%. Pinus densiflora community(5.8%) was observed on the ridge and Carpinu tschonoskii community distributed in the slope of the valley with 6.6%. Zelkova serrata and Prunus sargentii community were distributed in valley. The classification by TWINSPAN, ordination by DCA considering importance percentage and property of vegetation class were divided into 4 communities, which are community I(P. densiflora-Q. variabilis community), community II(Q. variabilis community), community III(C. tschonoskii community) and community IV(Mixed deciduous broad-leaved trees community). The age of Pinus densiflora was 32years old and Q. serrata was 36 years old in the community I, that of Q. variabilis was 64 years old in the community II, Q. serrata was 46 years old and C. tschonoskii was 45 years old in the community III, and Acer palmatum was 54 years old and Cornus controversa was 47 years old in the community IV. As the result of Shannon's index of species diversity, the community Iwas ranged from 0.9751 to 1.4199, community II was ranged from 1.0765 to 1.3278, community III was ranged from 1.0353 to 1.2881, and community IV was ranged from 1.1412 to 1.3807. The change of vegetation structure analyzed through the comparison with results of studies carried out 20 years ago were natural selection of P. densiflora, expansion of Quercus spp. and increase of C. tschonoskii. Especially, A. palmatum is dominated by Q. variabilis in canopy layer like the result of study 20 years ago. A. palmatum was analysed by 14.6% in the canopy layer of only mixed deciduous broad-leaved trees community. As a result of analysis of habitat property of Q. variabilis and A. palmatum, Q. variabilis was distributed in dry area with the low value of pH, O.M., exchangeable cations and Avail. P, and A. palmatum was located in the wet valley with huge value of nourishment. The tendency of reduction of bio-diversity by Sasa borealis is same as previous study but, the distributed areas were reduced in Naejangsan area.

• Korean Journal of Agricultural Science
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• v.35 no.2
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• pp.119-126
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• 2008

This study was carried out to find the botanical characters and effect of weed control for herbicides treatment after barley sowing. Barley variety used in study was "Yuyeon", hood-type awn for whole crop forage use, which developed at RDA in 2004. Sowing date was on 10th October, 2007, and was drilled as $60{\times}20cm$. Herbicides were treated on 2th day after barley sowing. Measured items were number and kinds of weeds at each treatment and growth characteristics and grain yield in barley. Cerastium holosteoides var. hallaisanense among weeds surveyed at tillering stages in Butachlor treatment were highly appeared, but Alopecurus aequalis var. amurensis did not appeared while Alopecurus aequalis var. amurensis was 39 plants and Capeslla bursa-pastoris was 37 plants in check. Occurrence of the Capeslla bursa-pastoris at primary survey and Cerastium holosteoides var. hallaisanense in ripening stage were high, while Alopecurus aequalis var. amurensis did not emerged. Botanical characteristics of barley each as plant height, number of tillers and spiklets per plant. surveyed at ripening stage were higher than check. Grain yield per 10a was the highest at Alachlor among treatments, while dry matter of leaf and culm were similar among treatments. Therefore, effect of yield increasing of barley by herbicide after sowing was reconfirmed through this study. Especially, effect of Alachlor was lightly high compared with others.

• Korean Journal of Plant Resources
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• v.24 no.4
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• pp.413-418
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• 2011

This study was carried out to establish a proper cultivation site and diagnose the drought-tolerance of Aster scaber and Synurus deltoides leaves by using Pressure-volume curves. In order to measure pressure-volume (P-V) curves, Aster scaber and Synurus deltoides were cut off above ground part and the tip of the cutting were placed in water, which was covered with a plastic bag. Samples were kept overnight (about 12 hours) in darkness at room temperature (20~25$^{\circ}C$) to achieve maximal turgor (full saturation). The pressure in the chamber was gradually increased from 0.3MPa to 1.8MPa by nitrogen gas. After measured, leaf samples were dried at 80$^{\circ}C$ for 48 hours and dry weight of each samples were determined. The result of the original bulk osmotic potential at maximum turgor ${\Psi}^{sat}_o$ sat was lower -0.8 MPa in Aster scaber leaves than -0.7 MPa Synurus deltoides leaves. Also the osmotic potential at incipient plasmolysis ${\Psi}^{tlp}_o$ in Aster scaber leave was -0.9 MPa. In contrast, the value of maximum bulk modulus of elasticity $E_{max}$ of Aster scaber leaves were approximately two folds higher than that of Synurus deltoides leaves. The values of the relative water content at incipient plasmolysis $RWC^{tlp}$ are all above 90% showing that the function of osmoregulation is somewhat better, and Vo/DW, Vt/DW, Ns/DW of Synurus deltoides leaves were approximately 1~2 times higher than that of Aster scaber leaves. Thus, responses to water relations of Aster scaber and Synurus deltoides such as ${\Psi}^{sat}_o$, ${\Psi}^{tlp}_o$, $E_{max}$, ${\Psi}_{P,max}$, $RWC^{tl}$ were shown that the Aster scaber leaves was slightly higher drought-tolerance than Synurus deltoides leaves. However, in both of Aster scaber and Synurus deltoides, occurring incipient plasmolysis at the high water content, have a relatively lower drought-tolerance property indicating that growth of these plants are cultivated appropriate in high moisture soil sites.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.3
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• pp.301-308
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• 2012

Near infrared reflectance spectroscopy (NIRS) has become increasingly used as a rapid and accurate method of evaluating some chemical compositions in forages. This study was carried out to explore the accuracy of near infrared spectroscopy (NIRS) for the prediction of chemical parameters of Italian ryegrass silages. A population of 267 Italian ryegrass silages representing a wide range in chemical parameters and fermentative characteristics was used in this investigation. Samples of silage were scanned at 2 nm intervals over the wavelength range 680~2,500 nm and the optical data recorded as log 1/Reflectance (log 1/R) and scanned in intact fresh condition. The spectral data were regressed against a range of chemical parameters using partial least squares (PLS) multivariate analysis in conjunction with spectral math treatments to reduced the effect of extraneous noise. The optimum calibrations were selected on the basis of the highest coefficients of determination in cross validation ($R^2$) and the lowest standard error of cross validation (SECV). The results of this study showed that NIRS predicted the chemical parameters with very high degree of accuracy. The $R^2$ and SECV were 0.98 (SECV 1.27%) for moisture, 0.88 (SECV 1.26%) for ADF, 0.84 (SECV 2.0%), 0.93 (SECV 0.96%) for CP and 0.78 (SECV 0.56), 0.81 (SECV 0.31%), 0.88 (SECV 1.26%) and 0.82 (SECV 4.46) for pH, lactic acid, TDN and RFV on a dry matter (%), respectively. Results of this experiment showed the possibility of NIRS method to predict the chemical composition and fermentation quality of Italian ryegrass silages as routine analysis method in feeding value evaluation and for farmer advice.