• Atmosphere
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• v.24 no.3
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• pp.303-315
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• 2014

Terrestrial ecosystem plays the important role as carbon sink in the global carbon cycle. Understanding of interactions of terrestrial carbon cycle with climate is important for better prediction of future climate change. In this paper, terrestrial carbon cycle is investigated by Hadley Centre Global Environmental Model, version 2, Carbon Cycle (HadGEM2-CC) that considers vegetation dynamics and an interactive carbon cycle with climate. The simulation for future projection is based on the three (8.5/4.5/2.6) representative concentration pathways (RCPs) from 2006 to 2100 and compared with historical land carbon uptake from 1979 to 2005. Projected changes in ecological features such as production, respiration, net ecosystem exchange and climate condition show similar pattern in three RCPs, while the response amplitude in each RCPs are different. For all RCP scenarios, temperature and precipitation increase with rising of the atmospheric $CO_2$. Such climate conditions are favorable for vegetation growth and extension, causing future increase of terrestrial carbon uptakes in all RCPs. At the end of 21st century, the global average of gross and net primary productions and respiration increase in all RCPs and terrestrial ecosystem remains as carbon sink. This enhancement of land $CO_2$ uptake is attributed by the vegetated area expansion, increasing LAI, and early onset of growing season. After mid-21st century, temperature rising leads to excessive increase of soil respiration than net primary production and thus the terrestrial carbon uptake begins to fall since that time. Regionally the NEE average value of East-Asia ($90^{\circ}E-140^{\circ}E$, $20^{\circ}N{\sim}60^{\circ}N$) area is bigger than that of the same latitude band. In the end-$21^{st}$ the NEE mean values in East-Asia area are $-2.09PgC\;yr^{-1}$, $-1.12PgC\;yr^{-1}$, $-0.47PgC\;yr^{-1}$ and zonal mean NEEs of the same latitude region are $-1.12PgC\;yr^{-1}$, $-0.55PgC\;yr^{-1}$, $-0.17PgC\;yr^{-1}$ for RCP 8.5, 4.5, 2.6.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.2
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• pp.145-156
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• 1996

The effects of priming with different polyethylene glycol (PEG 6, 000) solutions on the germination, emergence characteristics and early plant growth in rice, barley and wheat were investigated. Rice, barley and wheat seeds were subjected to various priming conditions of osmotic potentials (-0. 75, -1.00 and -1.50 MPa) of PEG, and incubation period were 5 days at 25, 20, 2$0^{\circ}C$, respectively. The percentage of water absorption was highest in barely, and lowest in rice, and all the treatments enhanced water absorption in barley, but showed no significant effects in rice and wheat. Respiration quotient was lower than none PEG treatment seeds, and those of barley and wheat were higher than rice regardless of PEG concentration, and that of rice increased with high PEG concentration. Total germination percentage of osmoconditioning seeds with PEG was higher than that of none treatment seed, and those of barley and wheat were significant. The artificially deteriorated seeds with PEG treatment seeds after ageing treatment could recover to nearly the same germination level as that of the control seeds. The effects of coating polymer were higher than osmoconditioning with PEG, and germination characteristics in rice showed varietal difference at PVP and waterlock at recoated seeds after PEG treatment. Osmoconditioning with PEG reduced mean germination and emergence time, but there was no difference among PEG concentrations. The plant height of PEG treaed seed in rice was taller and those of barely and wheat showed varietal difference, and those of polymer-coated seed after PEG treatment were different among the polymers. The dry weight of PEG treatment were different among the crops, and those were increased with the high PEG concentration. The emergence percentage of PEG-treated seed were higher than none-treated seed, and those were decreased with the increased PEG concentration, and the highest emergence percentage of rice, barley and wheat were 90, 50 and 50% soil moisture content, respectively. The time to emergence in rice was longer than barley and wheat, and those in rice was shortened in high soil moisture content, and barley and wheat were shortened in low soil moisture content.

• Korean Journal of Ecology and Environment
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• v.49 no.1
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• pp.51-61
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• 2016

This study was carried out to assess the carbon budget of two urban parks and one natural park and to prepare the plan for improving the ecological functions of the park including carbon sink. Net Ecosystem Production (NEP) of those study sites was calculated from the relationship between Net Primary Production (NPP) and soil respiration of each study site. To understand carbon budget of the whole area designated as the park, carbon budget of the urban park was analyzed by classifying the vegetated and the non-vegetated zones. NEP of the Nohae and the Sanggye parks calculated by reflecting areal size that the non-vegetated zones occupy were shown in -1.0 and $0.6\;ton\;C\;ha^{-1}yr^{-1}$, respectively. On the other hand, NEP of Mt. Bulam natural park as a reference site was in $2.3\;ton\;C\;ha^{-1}yr^{-1}$. Based on the result, the Nohae park was assessed as carbon source rather than carbon sink. On the other hand, the Sanggye park was classified as carbon sink but the role was poor compared with natural park. The result is, first of all, due to lower NPP of the vegetation introduced for the parks compared with natural vegetation. The other reason is due to wide arrangement of non-vegetated zone. To solve those problems and thereby to create the urban park with high ecological quality, selection of plant species suitable for the ecological characteristic of the park, their arrangement imitated natural vegetation, and ecological zoning were recommended.

• Journal of Wetlands Research
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• v.18 no.2
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• pp.201-207
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• 2016

In LID facilities treating stormwater runoff, various kinds of plants are applied for water circulation recovery and pollutant reduction. However, rapid changes of soil moisture due to the use of porous media and spread of deicing material during winter season cause slow plant growth that detrimentally leads to many problems including death of plants. Therefore, this study was performed to evaluate the salt resistance of plants, its effects on pollutants removal, and water circulation recovery. Eight different kinds of plants applicable to an LID facility were selected for the experiment, which were Bridal wreath (Spiraea japonica, S.J), Azalea (Rhododendron indicum, R.I), Dawn Redwood (Metasequoia glyptostroboides, M.G), Sweet flag (Acorus calamus A.C), Dwarf fan-shape columbine(Aquilegia flabellata, A.F), Pink (Dianthus chinensis, D.C), Pratia pedunculata (Pratia pedunculata, P.B) and Marigold (Tagetes patula, T.P). Woody plants such as S.P, R.I, and M.G appear to have less salt resistance compared to the other herbaceous plants. Specifically, M.G achieved the highest salt resistance among the other woody plants being followed by S.P, and R.I, respectively. For herbaceous plants, T.L and D.C have the higher salt resistances than that of A.C, P.B, and A.F, respectively. Regardless of the influence of salt to most of the plants, TN and TP were reduced more than 60% and the study suggests the M.G showed high pollutant removal efficiency and provided better water circulation by means of active photosynthesis and respiration due to higher growth.

• Journal of Korean Society of Forest Science
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• v.102 no.3
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• pp.372-381
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• 2013

The leaf growth and physiological characteristics of Forsythia saxatilis were investigated under different relative light intensities (RLI) and fertilization levels in order to find out the optimum environmental conditions for in-situ restoration. RLI and fertilization were four levels (30%, 43%, 63% of full sun and full sun) and three levels (non-fertilization, 2 times and 3 times of average forest soil in Korea), respectively. According to the increase of fertilization level under all RLI, leaf area increased and leaf dry weight and the ratio of leaf dry weight to leaf area decreased. As the fertilization level increased, photosynthetic pigment contents such as chlorophyll a, b and carotenoid under all RLI decreased. And pigment contents were the highest under full sun in the same fertilization level. Foliar nitrogen content under fertilization was higher than that under non-fertilization, and chlorophyll/nitrogen ratio decreased with the increase of fertilization level under all RLI. The increase of photosynthetic rate was observed with the increase of fertilization level at 63% of RLI and full sun, and dark respiration rate under fertilization was lower than under non-fertilization. Apparent quantum yield was lower at non-fertilization than that of fertilization, and it was highest at 63% of RLI under the same fertilization level. In conclusion, leaf growth and physiological characteristics of F. saxatilis could be improved under higher light conditions and fertilization.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.23 no.3
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• pp.163-171
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• 2017

Effects of different packaging methods for maintaining the shelf life and postharvest quality of iceberg lettuce (Lactuca sativa L.) were studied after harvesting in summer season. Lettuce heads were packaged in plastic crate with or without different films such as (A) Individual lettuce head sealed packaging with linear low density polyethylene (LLDPE) film; (B) Packaging lettuce head in plastic crate and wrapped with LLDPE film; (C): Individual lettuce head sealed packaging with perforated high density polyethylene (HDPE) film; (D) Packaging lettuce head in plastic crate and wrapped with perforated HDPE; and (E) Packaging lettuce head in plastic crate without any film (control), and stored at $2^{\circ}C$ for 35 days. Several quality parameters such as fresh weight loss, SPAD (soil & plant analyzer development) meter value, respiration rate, moisture content and appearance of lettuce were investigated. The lettuce wrapped with individually-sealed LLDPE film showed the lowest weight loss and the highest SPAD value rendering the best appearance index among the treataments throughout the three-week storage period at $2^{\circ}C$. Extending the freshness of iceberg lettuce during low temperature storage will definitely increase the salability potential in the domestic market even during summer season.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.2
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• pp.176-187
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• 1983

Volatile flavor components of garlic and factors which influence on its flavors were reviewed. Growth, storage and processing conditions influence on the flavor intensity of garlic. To intensify garlic flavors, it is desirable that sufficient sulfate nutrition be supplied to the soil of growing garlic and that the suggested proportions of mineral composition and water content be considered. And to maintain the flavor intensity of post harvested garlic, flavor losses taken place during over inter storage mainly due to respiration, sprout and decay, have to be minimized. Among the various storage methods, combination method of post harvest hot-air drying and low temperature ($0^{\circ}C$), low humidity (RH 70-75%) is useful. The flavor of processed garlic is very much decreased as compared with that of fresh, and the decreasing rate of flavors depends on processing method. The synthetic garlic flavors were obtained by three types based on intermediate thiosulfinate, S-alk(en) yl-$\small{L}$-cyteine sulfoxlde-alliinase fission products and $\small{L}$-5-alk (en)yl thiomethylhydantoin ${\pm}$ S-oxides. These synthetic garlic flavors may be promised to be applied to food additives.

• Korean Journal of Hazardous Materials
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• v.2 no.1
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• pp.18-26
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• 2014

We analyzed the demand of competent authorities requiring adequate technical information for initial investigation of chemical accidents. Reflecting technical reports on chemical accident response by environmental agencies in the U.S. and Canada, we presented information on environmental diffusion and toxic effects available for the first chemical accident response. Hydrogen fluoride may have the risk potential to corrode metals and cause serious burns and eye damages. In case of inhalation or intake, it could have severe health effects. The substance itself is inflammable, but once heated, it decomposes producing corrosive and toxic fume. In case of contact with water, it can produce toxic, corrosive, flammable or explosive gases and its solution, a strong acid, may react fiercely with a base. In case of hydrogen fluoride leak, the preventive measures are to decrease steam generation in exposed sites, prevent the transfer of vapor cloud and promptly respond using inflammable substances including calcium carbonate, sodium bicarbonate, ground limestone, dried soil, dry sand, vermiculite, fly ash and powder cement. The method for fire fighting is to suppress fire with manless hose stanchions or monitor nozzles by wearing the whole body protective clothing equipped with over-pressure self-contained breathing apparatus from distance. In case of transport accident accompanied with fire, evacuation distance is 1,600m radius. In cae of fire, fire suppression needs to be performed using dry chemicals, CO₂, water spray, water fog, and alcohol-resistance foam, etc. The major symptoms by exposure route are dyspnoea, bronchitis, chemical pneumonia and pulmonary edema for respiration, skin laceration, dermatitis, burn, frostbite and erythema for eyes, and nausea, diarrhea, stomachache, and tissue destruction for digestive organs. In atmosphere, its persistency is low, and its bioaccumulation in aquatic organism is also low.

• Journal of Korean Society of Forest Science
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• v.111 no.3
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• pp.405-417
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• 2022

The purpose of this study was to describe the photosynthetic features of Prunus maximowiczii and Prunus serrulate Lindl. var. pubescens (Makino) Nakai in response to drought stress. Specifically, we studied the effects of drought on photosynthetic ability and photosystem II activity. Drought stress (DS) was induced by cutting the water supply for 30 days. DS decreased the moisture contents in the soil, and between the 10th and 12th days of DS, both species had 10% or less of x., After the 15th day of DS, it was less than 5%, which is a condition for disease to start. We observed a remarkable decrease of maximum photosynthesis rate starting from 10th day of DS; the light compensation point was also remarkable. Dark respiration and net apparent quantum yield decreased significantly on the 15th day of DS, and then increased on the 20th day. In addition, the stomatal transpiration rate of P. maximowiczii decreased significantly on the15th day of DS, and then increased on the 20th day. Water use efficiency increased on the 15th day of DS, and then decreased on the 20th day. The stomatal transpiration rate of P. serrulate decreased significantly on the 20th day of DS, and then increased afterward, while its water use efficiency increased on the 20th day of DS, and then decreased afterward. These results indicate that the closure of stoma prevented water loss, resulting in a temporary increase of water use efficiency. Chlorophyll fluorescence analysis detected remarkable decreases in the functional index (PI_ABS) and energy transfer efficiency in P. maximowiczii after the 15th day of DS. Meanwhile, photosystem II activity decreased in P. serrulate after 20 days of DS. In addition, Ts-Ta, PI_ABS, DI_O/RC, ET_O/RC followed similar trends as those of the soil moisture content and photosynthetic properties, indicating that they can be used as useful variables in predicting DS in trees.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.4
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• pp.227-234
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• 2019

This study was performed to investigate the effect of heat-stressed environment on rumen microbial diversity in Holstein cows. Rectal temperature and respiration rate were measured and rumen fluid was collected under normal environment (NE; Temperature humidity index (THI)=64.6) and heat-stressed environment (HE; THI=87.2) from 10 Holstein cows (60±17.7 months, 717±64.4 kg) fed on the basis of dairy feeding management in National Institute of Animal Science. The rumen bacteria diversity was analyzed by using the Illumina HiSeq^TM 4000 platform. The rectal temperature and respiratory rate were increased by 1.5℃ and 53 breaths/min in HE compared to that in NE, respectively. In this study, HE exposure induced significant changes of ruminal microbe. At phylum level, Fibrobacteres were increased in HE. At genus level, Ruminococcaceae bacterium P7 and YAD3003, Butyrivibrio sp. AE2032, Erysipelotrichaceae bacterium NK3D112, Bifidobacterium pseudolongum, Lachnospiraceae bacterium FE2018, XBB2008, and AC2029, Eubacterium celulosolvens, Clostridium hathewayi, and Butyrivibrio hungatei were decreased in HE, while Choristoneura murinana nucleopolyhedrovirus, Calothrix parasitica, Nostoc sp. KVJ20, Anabaena sp. ATCC 33047, Fibrobacter sp. UWB13 and sp. UWB5, Lachnospiraceae bacterium G41, and Xanthomonas arboricola were increased in HE. In conclusion, HE might have an effect to change the rumen microbial community in Holstein cows.