• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.62.1-62.1
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• 2015

Polarization of the light reflected off the Moon provides information on the size and composition of the particles in the lunar regolith. The mean particle size of the regolith can be estimated from the combination of the albedo and degree of polarization, while the color ratio of the parallel-component polarization (CP) has been suggested to be related to the amount of nanophase metallic iron (npFe^0) inside the regolith particles. Both the mean size and npFe^0 abundance of the particles have been used as maturity indicators of the regolith since sustained impacts of high energy particles and micro-meteoroids cause comminution of particles and production of npFe^0. Based on our multispectral polarimetric observations of the whole near side of the Moon in the U, B, V, R, and I bands, we compare the maps of the mean particle size, CP, and the optical maturity (OM). We find that the mean particle size map is sensitive to the most immature (~0.1 Gyr) soil, the OP map to the intermediate immaturity (a few 0.1 Gyr) soil, and the CP map to the least immature (~1 Gyr) soil.

• Journal of Ecology and Environment
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• v.42 no.1
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• pp.12-19
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• 2018

Background: The objective of this study was to determine the relationship between soil environmental factors and halophyte distribution in the west coast of South Korea. Soils of our study sites were categorized into two groups: salt marsh and estuary marsh. Results: Salinity was higher in the salt marsh group than that in the estuary marsh group. However, total nitrogen, silt, and clay contents were higher in the estuary marsh group than those in the salt marsh group. Although altitude had a wider range in the salt marsh group, the mean altitude was higher in the estuary marsh group than that in the salt marsh group. Annual halophytes of seed propagation species were distributed parallel to the coast line on salt marsh. Higher coverage of vegetation was found in the area closer to the coast line. Plant density was higher near dead parental plants in estuary marsh, showing less difference in area that was more distant from the coast line. Conclusions: Results of canonical correspondence analysis (CCA) for vegetation distribution and sediment environmental factors and germination analysis in the coast line showed significant relationship with halophyte distribution. Therefore, they can be used as an indicator of coastal plant movement due to sea level rise.

• The Korean Journal of Ecology
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• v.20 no.2
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• pp.125-132
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• 1997

A study of forest vegetation in Mt. $T\v{o}kyu$ National Park was investigated by ordination technique. By TWINSPAN(Two-Way Indicator Species Analysis) method, 10 groups were recognized as follows: pinus densiflora, Quercus variabilis, Quercus serrata, Quercus mongolica-Rhododendron schlippenbachii, Quercus mongolica-Abies koreana, Quercus mongolica-Acer pseudo-sieboldi-amum, Quercus mongolica-Symplocos chinensis for. pilosa, Carpinus laxiflora, Fraxinus mandshurica and Taxus cuspidata groups. The floristic composition of these groups showed high correlation to soil moisture(r=0.831), altitude(r=0.784), topography(r=-0.722), organic matter(r=0.642), and pH(r=-0.509) among various environmental factors. According to the results of CCA(Canonical Correspondence Analysis) Pinus densiflora group and Quercus variabilis group were situated in a xeric area at a lower altitude where soil nutrients were poor compared with the other groups. Fraxinus mandshurica group was distributed throughout the valley with high soil moisture and good nutrients, Quercus serrata group and Carpinus laxiflora group were found in the low altitude region with good nutrients, Quercus mongolica group, at the high altitude region with good nutrients, and Quercus mongolica-Acer koreana and Taxus cuspidata at higher altitudes(1, 400-1600 m).

• Korean Journal of Environmental Agriculture
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• v.22 no.1
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• pp.41-46
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• 2003

The suitability of the life Cycle Assessment (LCA) methodology to analyze the environmental impact of rice cultivation with different fertilizing systems is investigated. The arst part of an LCA is an inventory of parameters used and emissions released due to the system under investigation. In the following step, the Life Cycle Impact Assessment the inventory data were analyzed and aggregated in order to finally get one index representing the total environmental burden. For the life Cycle Impact Assessment (LCIA) the Eco-indicator 95 method has been chosen because this is well documented and regularly applied impact assessment method. The resulting index is called Eco-indicator value. The higher the Eco-indicator value the stronger is the total environmental impact of an analyzed fertilizing system. The rice field experiment conducted in middle parts of korea was chosen as an example for the life cycle impact analysis. In this experiment the treatments were consisted of none fertilizer plot (NF), standard fertilizer plot (SF) applied chemical fertilizers based on soil chemical analysis before rice transplanting, and efflux fertilized plot (EF) applied with pig wastes fermented as the same rates of SF plot as basis on total nitrogen content. The obtained Eco-indicator values were clearly different among the treatments in the rice trial. The total Eco-indicator values for SF and EF have been observed 58 and 38% relative to the NF, respectively. For all the treatments the environmental effects of eutrophication contributed most to the total Eco-indicator value. The results appeared that the LCA methodology is basically suitable to assess the environmental impact associated with different fertilizer applications for rice cultivation. A comparative analysis of the fertilizing system's contribution to global warming and eutrophication is possible.

• Journal of Korean Society of Forest Science
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• v.109 no.2
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• pp.157-168
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• 2020

The sensitivity of forest soil to acidification in the Republic of Korea (ROK) was evaluated based on pH_H2O, cation exchange capacity (CEC), and base saturation (BS). Sensitivity to acidification was categorized into three grades: adequate level (AL, pH ≧ 4.2, CEC ≧ 15cmol/kg, BS ≧ 15%), caution level (CL, at least one indicator is below AL), and severe Level (SL, all three indicators are below AL). Soil samples were collected from the 65 stationary monitoring plots (40 × 40 ㎢), distributed throughout ROK. Only 19% of soil samples were classified as AL, while 66% and 15% were CL and SL, respectively. The median of pH_H2O, CEC, BS, and Ca/Al indicator in AL soils was pH 4.64, 20.7cmol/kg, 29%, and 6.3, respectively. Moreover, BC_ex (K⁺, Mg²⁺, Ca²⁺) and available phosphorus (AP) concentration compared with a threshold value and molar ratio of BC_ex and AP to total nitrogen (TN) was high. This indicates that AL soils have a good nutrient condition. The molar Ca/Al ratio, an indicator for toxicity of exchangeable aluminum (Al_ex), was more than 1, indicating no negative impact of Al_ex on plant growth. On the contrary, the median of pH_H2O, CEC, and BS in SL soils was pH 4.02, 13.2cmol/kg, and 10%, respectively. The Ca/Al index was less than 0.6, which indicates that negative impacts of Al_ex on plants were high. Furthermore, both the concentration of BC_ex in SL soils and the BC_ex/TN ratio were the lowest among the three acidity degrees. This shows that SLsoils can be degraded by soil acidification compared with less acidic soils.

• Journal of the Korea Organic Resources Recycling Association
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• v.30 no.1
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• pp.5-11
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• 2022

This research evaluated the long-term application effects of different soil amendments on yield, dissolved organic carbon, nitrogen and soil organic carbon stock in rice paddy. The experiment consisted of four different fertilizations; Inorganic fertilization (NPK), NPK+Lime (NPKL), NPK+Silicate (NPKS), NPK+Compost (NPKC). There was no significant difference in rice yield between the treatment groups in 1995, but the rice yields in the NPKL and NPKC treatments in 2019 increased by 4.3% and 14.3% compared to NPK. In terms of soil properties, the pH of NPKS(6.7) and NPKL(6.4) in 2019 increased the most compared to the soil pH before experiment(5.2). The organic matter(OM) content from NPKC treatment increased upto 34 and 27 g kg^-1 in year of 1995 and 2019, respectively, compared to before the test. In NPKS and NPKL treatment, labile carbon and nitrogen content, used as a soil quality indicator, increased by 1.1-1.9 times over the control. From these result, it is suggested that type and application rate of soil amendment should be determined based on the soil analysis before cultivation for sustainable agricultural environment and productivity.

• Research in Plant Disease
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• v.18 no.3
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• pp.225-230
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• 2012

Bacteriophages of Pectobacterium carotovorum subsp. carotovorum which causes soft rot on diverse vegetables had been isolated from 6 major Chinese cabbage cultivation areas in Korea. In order to isolate bacteriophages, total 15 different strains of P. carotovorum subsp. carotovorum isolated from nation-wide of Korea had been used as a host. When we tested 30 different soil samples individually from Pyeongchang and Taebaek with 15 different strains as a host, Taebek soil samples showed bacteriophage plaques with almost all different indicator strains but Pyeongchang soil samples showed plaques only with P. carotovorum subsp. carotovorum Pcc2 and Pcc3 strains. Especially, P. carotovorum subsp. carotovorum Pcc3 strain was able to produce plaques with almost all soil samples. Thus, this strain can be used as an indicator strain for P. carotovorum subsp. carotovorum bacteriophage screening. Electron microscope observation revealed P. carotovorum subsp. carotovorum bacteriophages isolated in Korea were belonged to three different families, Myoviridae, Siphoviridae and Podoviridae in order Caudovirales.

• Korean Journal of Environment and Ecology
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• v.38 no.2
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• pp.156-168
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• 2024

This study was carried out to provide fundamental data for forest land and the environment by investigating the vegetation structure and soil properties of forest land where Sarcodon impricatus are present. The study area was divided into the Quercus mongolica community, dominated by Q. mongolica and the Quercus variabilis community, a mixed forest with Q. variabilis, Q. mongolica and Pinus densiflora. Also, Calamagrostis arundinacea in the former community and Disporum smilacinum and Carex siderosticta in the latter community showed significant levels as indicator species. Both communities showed a strong correlation between available phosphate and pH, sand, and clay, and the high organic matter content and slightly acidic pH of the soil are believed to be related to the development of S. impricatus. The species appearing at the lower layer continue to dominate because the species appearing at the upper layer have secured realized niches. The site was distributed in a relatively humid place in a north-east direction, and soil was developed with a thin litter layer and low rock exposure. In the selected S. impricatus growing areas, vegetation centered on highly adaptable species to disturbance or external interference was developed. Therefore, it is expected to be used as fundamental data to promote the occurrence of S. impricatus during artificial cultivation, as it is possible to identify the stand where S. impricatus occurs indirectly.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.4
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• pp.280-288
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• 2009

To identify controlling factors for spatial variation of vegetation in reclaimed tidal flats, plant stands were investigated in a newly reclaimed as well as three matured tidal flats, and a natural tidal flat in the midwest coast of Korea. Electrical conductivity of saturated soil extract (ECe) was measured to assess soil salinity. Soil salinity differed significantly among plant stands. Depending on soil salinity, plant species showed different niches: glycophyte predominated low saline spots, halophyte predominated high saline spots. Soil salinity for each plant habitats was in order of as follow: bare soil or plant wilted > mixed pioneer halophyte > pioneer halophyte > mixed with pioneer halophyte and facultative halophyte > mixed facultative halophyte > facultative halophyte > mixed with facultative halophyte and glycophyte > glycophyte > mixed glycophyte stands. These results suggested that plant distribution might have been influenced by spatial edaphic gradient (soil salinity), and thus it could be utilized as an indicator for field soil salinity gradient. Relationship between soil salinity and plant distribution was not different among the aged reclaimed tidal flats, suggesting that the vegetative population might have changed into a similar direction since the reclamation.

• Korean Journal of Environmental Biology
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• v.17 no.4
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• pp.421-426
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• 1999

Species composition, species diversity, standing biomass and soil properties of the grasslands, which are developed in the vicinity of Yoch’on Industrial Complex, were investigated. The grassland divided into three types, mugwort (Artemisia princeps var. orientalis) community, porkweed (Phytolacca americana) community and eulalia (Miscanthus sinensis) community by physiognomy Standing biomass of mugwort community, porkweed community and eulalia community was 5,645 g/$m^2$, 2,827 g/$m^2$ and 9,048 g/$m^2$, respectively. Species diversity of mugwort community, porkweed community and eulalia community was 1.03, 0.54 and 0.26, respectively. Total N, available P, total S and soluble S of the top soil in this grassland were much higher than those in other areas. Most of the species in this grassland are indicator species of soil eutrophication.