• Korean Journal of Agricultural and Forest Meteorology
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• 제14권4호
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• pp.196-206
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• 2012

Studies of seasonal changes in $C_3/C_4$ mixed communities are rare, particularly in Asian summer monsoon climate zones. In our present study, seasonal changes in the profile and coverage of $C_3$ and $C_4$ plants were investigated in 2009 in Haenam, Yeongdong and Cheorwon regions of South Korea (all at different latitudes). The aim was to estimate the impacts of temperature and sunshine duration on species composition and transition timing of the $C_3$ and $C_4$ plants. From our results, the number of $C_3$ plants was found to increase from early spring to mid-May, and then decrease again until September in the Haenam and Yeongdong regions, but continuously increase from early spring to September in the Cheorwon region under relatively low summer temperatures. On the other hand, the number of $C_4$ plants increased from June or July to September in all three regions. These seasonal changes in species number and ratio have a direct impact upon species diversity which is highest when there are no dominant species. The relative coverage and relative summed dominance ratio (SDR') of the $C_3$ plants decreased from spring to autumn, but increased for the $C_4$ plants during this time in an exponential fashion with increasing accumulated temperature and sunshine duration. The transition timing from $C_3$ to $C_4$ plants occurred when the sum of sunshine duration for the days with daily mean temperature above $5^{\circ}C$ was 1017 hrs for the SDR'.

• Journal of Plant Biology
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• 제18권1호
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• pp.1-10
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• 1975

Development of a model system for mode of action studies of $SO_2$ was attempted with a plant tissue. Leaf disks, 1.0cm diameter, cut from the lamina of lettuce leaves, were floated on the testing medium and placed in light or dark condition to investigate the discoloration pattern with various sources of $SO_2$. Discoloration of leaf disks tended to be more serious with higher concentrations of $SO_2$ and on exposure to the light. Leaf disks were more severely discolored at lower pH with constant SO2 concentration. These discoloration patterns were highly reproducible and similar in all sources of $SO_2$. Spectrophotometric evidence suggested that light-mediated discoloration of leaf disks in the presence of $SO_2$ might occur mainly through chlorophyll ${\alpha}$ degradation.

• Nuclear Engineering and Technology
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• 제14권3호
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• pp.116-121
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• 1982

The uptake and retention of strontium-90 from seawater by the seaweed Undaria pinnatifda(sea mustard) varied depending on the plant part, exposure time, salinity, contents of stable strontium and calcium, and presence of chelating agent in the seawater. The concentration factors attained at equilibrium were in the range of 50 and it was evident that the bioaccumulation was largely due to the adsorption of the radionuclide on the surface of seaweed.

• Proceedings of the Korea Water Resources Association Conference
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• 한국수자원학회 2018년도 학술발표회
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• pp.51-51
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• 2018

기후변화에 따른 기온이 상승 및 강수 패턴의 변화로 인하여 자연재해로 인한 피해가 증가하고 있다. 다른 자연재해들과는 달리 가뭄은 공간적 및 가뭄에 영향을 받는 사회적, 경제적, 환경적 및 심리적인 피해 등에 있어 대단히 광범위하다. 특히, 오랜 기간 동안의 무강우로 인해 자연생태계의 균형을 변화시켜 많은 물고기와 야생 생물 종에 해를 끼칠 수 있으며, 식물 성장 저하, 화재 및 곤충 발생의 증가, 물 순환 및 지방 종의 멸종 증가와 같은 환경학적 문제를 야기할 수 있다. 우리나라의 또한 폭염과 마른 날씨로 인하여 멸종위기종의 어류 서식지를 잃는 등의 문제가 발생하기도 하였다. 이러한 환경-생태학적 가뭄의 발생빈도가 증가하고 있으나, 이에 대한 많은 연구가 이루어지지 못한 질정이다. 따라서 본 연구에서는 가뭄에 따른 환경-생태학적 영향 등을 파악하고, 이에 따른 하천 수질과 식생의 변화 등을 분석하여 가뭄 상태에 따른 환경-수생태의 영향을 살펴보고자한다.

• Korean Journal of Soil Science and Fertilizer
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• 제45권2호
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• pp.248-252
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• 2012

To evaluate the possibility of water plant wastes in composting for agricultural recycling, Phragmites communis (PHRCO), Typha orientalis (TYHOR) and Zizania latifolia (ZIZLA) were used as a compost materials. In composting basin, cumulative oxygen consumptions of the compost used by water plant wastes were rapidly increased at the early stage and slightly decreased in around 15 days. Cumulative oxygen consumptions under different water plant wastes were higher in the order of TYHOR > ZIZLA > PHRCO. Temperature changes during composting process were rapidly increased at the early stage and then slowly decreased to $30{\sim}40^{\circ}C$. The maximum temperatures were higher in the order of ZIZLA ($72.2^{\circ}C$ at 11 days after starting composting) > TYHOR ($70.2^{\circ}C$ at 10 days after starting composting) > PHRCO ($66.5^{\circ}C$ at 7 days after starting composting). Oxygen consumptions at maximum temperature were higher in the order of TYHOR ($12,485mg\;O_2\;kg^{-1}$) > ZIZLA ($12,400mg\;O_2\;kg^{-1}$) > PHRCO ($9,340mg\;O_2\;kg^{-1}$). Organic matter contents, moisture contents and OM/N rates in the compost ranged 39.5~44.8%, 29.6~35.6% and 27.9~32.9, respectively. Considering that water plant waste can supply some of the nutrient requirements of crops and is a valuable fertilizer.

• Journal of Plant Biotechnology
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• 제42권3호
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• pp.257-264
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• 2015

To determine whether metabolite fingerprinting for whole cell extracts based on Fourier transform infrared (FT-IR) spectroscopy can be used to discriminate and compare metabolic equivalence, standard medicinal parts from four medicinal plants (Cynanchum wilfordii Hemsley, Atractylodes japonica Koidz, Polygonum multiflorum Thunberg and Astragalus membranaceus Bunge) and their in vitro-produced adventitious roots were analyzed by FT-IR spectroscopy. The principal component analysis (PCA) and partial least square discriminant analysis (PLS-DA) from the FT-IR spectral data showed that the whole metabolic pattern from Cynanchum wilfordii was highly similar to Astragalus membranaceus. However, Atractylodes japonica and Polygonum multiflorum showed significantly different metabolic patterns. Furthermore, adventitious roots from Cynanchum wilfordii and Astragalus membranaceus also showed similar metabolic patterns compared to their standard medicinal parts. These results clearly show that mass proliferation of adventitious roots may be applied to aquire novel supply of standard medicinal parts from medicinal plants. However, the whole metabolic pattern from adventitious roots of Atractylodes japonica and Polygonum multiflorum were not similar to their standard medicinal parts. Furthermore, FT-IR spectroscopy combined with multivariate analyses established in this study may be applied as an alternative tool to discriminate the whole metabolic equivalence from several standard medicinal parts. Thus, we suggest that these metabolic discrimination systems may be applied for metabolic standardization of herbal medicinal resources.

• Journal of Nutrition and Health
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• 제50권1호
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• pp.10-24
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• 2017

Purpose: GST (glutathione S-transferase) M1 and T1 gene polymorphisms are known to affect antioxidant levels. This study was carried out to evaluate genetic susceptibility by measuring the effect of DNA damage reduction in the Korean diet by vegetable food according to GST gene polymorphisms using the ex vivo method with human lymphocytes. Methods: Vegetable foods in the Korean diet based the results of the KNHANES V-2 (2011) were classified into 10 food groups. A total of 84 foods, which constituted more than 1% of the total intake in each food group, were finally designated as a vegetable food in the Korean diet. The Korean diet applied in this study is the standard one-week meals for Koreans (2,000 Kcal/day) suggested by the 2010 Dietary Reference Intakes for Koreans. Ex vivo DNA damage in human lymphocytes was assessed using comet assay. Results: In the Korean food group, the DNA damage protective effect of GSTM1 and GSTT1 was found to be greater in mutant type and wild-type, respectively. and the DNA damage protective effect according to the combined genotype of GSTM1 and GSTT1 was different depending on the food group. On the other hand, in Korean Diet, the DNA damage protective effect appeared to be larger in GSTM1 wild-type than in mutant type and was found to not be affected by GSTT1 genotype. Conclusion: These results can be used as basic data to demonstrate the superiority of the antioxidant function of Korean dietary patterns and food groups. Furthermore, it may be a starting point to begin research on customized antioxidant nutrition according to individual genes.

• Korean journal of applied entomology
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• 제50권2호
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• pp.97-105
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• 2011

Understanding the metapopulation structure and movement of a species are required for conserving the species. In this paper, migration patterns and connectivity of patches of a threatened butterfly, Parnassius bremeri Bremer, were postulated using the mark-release-recapture (MRR) technique in a habitat located in the mid-southern region of the Korean peninsula. A total of 194 individuals were captured (137 males and 57 females) and, of them, 93 individuals (73 males and 20 females) were recaptured during the MRR experiment. The migration analysis showed 23-150% immigration and 28-53% emigration. There were high correlations between the migrating individuals and the distance between patches, but there was no correlation between migrating individuals and patch size or between migrating individuals and the number of host plants. Consequently, the migration of butterflies occurred frequently between closer patches, while patch size and quantity of the food plant had minor effects on migration behavior. Additionally, males migrated more frequently than females. Analysis of the migration patterns of P. bremeri showed that the central patch played an important role on linking patch groups and more frequent migrations were monitored between nearby patches than between the remote patches. This study suggested that active migrations take place between the neighboring multiple patches and these are accelerated if there is a stepping-stone patch between them.

• Korean Journal of Plant Taxonomy
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• 제42권1호
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• pp.50-63
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• 2012

A comparative study of the petiole anatomy in the tribes Forsythieae (Abeliophyllum, Forsythia) and Fontanesieae (Fontanesia), including one related genus Myxopyrum belonging to Myxopyreae, was carried out using light microscopy. The anatomical characteristics of the distal, medial and proximal parts of the petiole were studied to document any differences. We are described in detail based on their quantitative and qualitative characteristics. Three crystal types (acicular, druse, and prismatic crystals) were found in both Fontanesia and Myxopyrum within all of the studied taxa. Uni-cellular non-glandular trichomes were found in Abeliophyllum and three Forsythia taxa (F. europaea, F. giraldiana, and F. japonica). All features were compared and the vascular patterns of the petiole were distinguished in two types: Type 1A: Trace continuous arc - without crystals (Abeliophyllum, Forsythia), 1B: with crystals (Myxopyrum), Type 2: Trace invaginating at ends with crystals (Fontanesia). A detailed anatomical description of the studied taxa is provided, and its systematic importance is also briefly discussed. In conclusion, some petiole anatomical characteristics (e.g., the main vascular patterns, the presence/absence of crystals) can be useful for diagnostic features as well as partly for supporting the recently proposed molecular phylogeny.

• Journal of the Korean Geographical Society
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• 제49권1호
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• pp.45-56
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• 2014

Data composite methods have been typically applied to satellite-based vegetation index(VI) data to continuously acquire vegetation greenness over the land surface. Data composites are useful for construction of long-term archives of vegetation indices by minimizing missing data or contamination from noise. In addition, if multi-sensor vegetation indices that are acquired during the same composite periods are used interchangeably, data stability and continuity may be significantly enhanced. This study evaluated the influences of sensor geometry on MODIS vegetation indices and investigated data compatibility of two difference vegetation indices, the Normalized Difference Vegetation Index(NDVI) and the Enhanced Vegetation Index(EVI), for potential improvement of long-term data construction. Relationships between NDVI and EVI turned out statistically significant with variations among vegetation covers. Due to their curvilinear relationships, NDVI became saturated and leveled off as EVI reached high ranges. Correlation coefficients between Terra- and Aqua-based vegetation indices ranged from 0.747 to 0.963 for EVI, and from 0.641 to 0.880 for NDVI, showing better compatibility for EVI compared to NDVI. In-depth analyses of VI outliers that deviated from regression equations constructed from the two different sensors remain as a future study to improve their compatibility.