• Journal of agriculture & life science
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• v.43 no.2
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• pp.1-8
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• 2009

The limestone area covers the narrow range of the Korean Peninsula, and it consists of a peculiar ecosystem and topography. Therefore, this study on limestone area was carried out classification of vegetation type, physicochemical properties of forest soils and correlation between environment factors and vegetation types in order to furnish fundamental data for the forest management of limestone area. Forest vegetation was classified into two community groups such as Quercus variabilis community group and Quercus mongolica community group, and it was classified into eight vegetation units. Soil texture of survey sites showed largely silt loam and soil pH indicated the value of mean 7.55 in the A layer of soil profile. Content of exchangeable cation such as calcium ion ($Ca^{2+}$) and magnesium ion ($Mg^{2+}$) showed $26.04cmol_{c}/kg$ and $2.93cmol_{c}/kg$, respectively, which was about ten times higher than average of other regions of Korea. According to corelation between environmental factors and vegetation units, Q. variabilis community group was positively correlated to soil pH, slope degree and the rate of bare rock, and content of calcium ion ($Ca^{2+}$), and then Q. mongolica community group was positively correlated to altitude, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.6
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• pp.380-386
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• 2001

This study was conducted to investigate the influence of the root zone temperature on the changes in soil physicochemical environment and the growth of the apple trees. Root zone temperatures applied were 20. 25. 30. and $35^{\circ}C$. A pot experiment of 4-year-old fruit-bearing Fuji/M.26 apple trees was done from May 15. 1997 to August 15. 1997. Shoot length and shoot number of 4-year-old Fuji/M.26 was longest at $30^{\circ}C$ but decreased at $35^{\circ}C$. Oxygen concentrations in soil air were maintained from 17 to 18% at $20^{\circ}C$ but fluctuated from 10 to 14% at the end at $35^{\circ}C$. Carbon dioxide concentrations in soil air was highest at $35^{\circ}C$. Organic matter contents in soil decreased as root zone temperature and duration of treatment increased. Nitrate and ammonium contents in soil increased with rising root zone temperature in the beginning but nitrate contents decreased at $35^{\circ}C$ as time progressed. Nitrate content was higher in 10~15cm subsoil than in 25~30cm subsoil.

• Journal of Conservation Science
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• v.37 no.6
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• pp.748-766
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• 2021

The Iksan Ssangneung (twin tombs), a pair of tombs comprising the Daewangneung (large royal tomb) and the Sowangneung (small royal tomb), were constructed in the typical style of stone tunnel and chamber tombs in the Baekje Kingdom during the Sabi period (538 to 660 AD) of ancient Korea. Soil layers exposed during excavation of Sowangneung in a trench east of the tomb are: the bottommost layer, the ground level layer, the Panchuk (rammed earth) layer of the Baekje, the layer created by a grave robbery, and soil recovered during the Japanese colonial period. Soil samples were obtained by segmenting an easy stratigraphic horizon into sub categorized soil layers, and their material properties were analyzed; they are composed mainly of sandy loam based on the particle size distributions. In the site foundation, loamy sand is packed in the bottommost layer, and sandy loam with high sand and silty sand fills most of the overlying layer. The central and topmost portion of the Baekje layer is composed of loam with high clay content. All soil layers show geochemical behaviors similar to those of the bottommost layer. X-ray diffraction analysis verified kaolinite in all layers, also observed in soil layers displaying high crystallinity. Kaolinite and halloysite were identified by scanning electron microscopy. Thus, we conclude that the Baekje layer of the Sowangneung is composed of sandy loam containing kaolin procured from near the site. An impermeable middle to upper layer was created using viscous loam. The top of the tomb was closed tightly.

• Economic and Environmental Geology
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• v.55 no.6
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• pp.727-736
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• 2022

Ice wedges are subsurface ice mass structures that formed mainly by freezing precipitation with airborne dust and surrounding soil particles flowed through the active layer into the cracks growing by repeating thermal contractions in the deeper permafrost layer over time. These ice masses characteristically contain high concentrations of solutes and solids. Because of their unique properties and distribution, the possibility of harnessing ice wedges as an alternative archive for reconstructing paleoclimate and paleoenvironment has been recently suggested despite limited studies. It is imperative to preserve the physicochemical properties of the ice wedge (e.g., solute concentration, mineral particles) without any potential alteration to use it as a proxy for reconstructing the paleo-information. Thawing the ice wedge samples is prerequisite for the assessment of their physicochemical properties, during which the paleo-information could be unintentionally altered by any methodological artifact. This study examined the effect of thawing conditions and procedures on the physicochemical properties of solutes and solid particles in ice wedge samples collected from Cyuie, East Siberia. Four different thawing conditions with varying temperatures (4 and 23℃) and oxygen exposures (oxic and anoxic) for the ice wedge sample treatment were examined. Ice wedge samples thawed at 4℃ under anoxic conditions, wherein biological activity and oxidation were kept to a minimum, were set as the standard thawing conditions to which the effects of temperature and oxygen were compared. The results indicate that temperature and oxygen exposure have negligible effects on the physicochemical characteristics of the solid particles. However, the chemical features of the solution (e.g., pH, electric conductivity, alkalinity, and concentration of major cations and trace elements) at 4℃ under oxic conditions were considerably altered, compared to those measured under the standard thawing conditions. This study shows that the thawing condition of ice wedge samples can affect their chemical features and thereby the geochemical information therein for the reconstruction of the paleoclimate and/or paleoenvironment.

• Journal of Wetlands Research
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• v.26 no.2
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• pp.168-181
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• 2024

Constructed wetlands (CWs) deliver a range of ecosystem services, including the removal of contaminants, sequestration and storage of carbon, and enhancement of biodiversity. These services are facilitated through hydrological and ecological processes such as infiltration, adsorption, water retention, and evapotranspiration by plants and microorganisms. This study investigated the correlations between microbial populations, soil physicochemical properties, and treatment efficiency in a horizontal subsurface flow constructed wetland (HSSF CW) treating runoff from roads and parking lots. The methods employed included storm event monitoring, water quality analysis, soil sampling, soil quality parameter analysis, and microbial analysis. The facility achieved its highest pollutant removal efficiencies during the warm season (>15℃), with rates ranging from 33% to 74% for TSS, COD, TN, TP, and specific heavy metals including Fe, Zn, and Cd. Meanwhile, the highest removal efficiency was 35% for TOC during the cold season (≤15℃). These high removal rates can be attributed to sedimentation, adsorption, precipitation, plant uptake, and microbial transformations within the CW. Soil analysis revealed that the soil from HSSF CW had a soil organic carbon content 3.3 times higher than that of soil collected from a nearby landscape. Stoichiometric ratios of carbon (C), nitrogen (N), and phosphorus (P) in the inflow and outflow were recorded as C:N:P of 120:1.5:1 and 135.2:0.4:1, respectively, indicating an extremely low proportion of N and P compared to C, which may challenge microbial remediation efficiency. Additionally, microbial analyses indicated that the warm season was more conducive to microorganism growth, with higher abundance, richness, diversity, homogeneity, and evenness of the microbial community, as manifested in the biodiversity indices, compared to the cold season. Pollutants in stormwater runoff entering the HSSF CW fostered microbial growth, particularly for dominant phyla such as Proteobacteria, Actinobacteria, Acidobacteria, and Bacteroidetes, which have shown moderate to strong correlations with specific soil properties and changes in influent-effluent concentrations of water quality parameters.

• Korean Journal of Environment and Ecology
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• v.34 no.1
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• pp.85-92
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• 2020

The purpose of this study is to provide base information that can be utilized in surveying the status of landscape management within apartment complexes and grasping the conditions of the soil for planting plants, as a way to improve the quality of green spaces by repairing poorly vegetated spaces within apartment complexes and remodeling them with diverse species of plants. Considering that trees and shrubs of equal sizes are simultaneously planted upon the completion of apartment complexes, they were divided based on their completion year at the interval of 5 years and differences in the growth of trees and the components of soil over time were analyzed. Out of the species of trees planted in all the 9 apartment complexes surveyed in this study, the growth of 4 species of needleleaf trees and 4 species of broadleaf trees were surveyed. Juniperus chinensis 'Kaizuka' and Pinus densiflora Siebold & Zucc. out of the needleleaf trees and Malus floribunda Siebold ex Van Houtte out of the broadleaf trees showed the highest growth rate when over 5 years passed after planting and their growth rate decreased when over 10 years passed. Platycladus orientalis and Acer palmatum Thunb. in the apartment complexes that were built over 10 years ago showed the highest growth rate, which indicates that the species require a relatively long period of time for growth. The hardness of the soil at the areas where trees were planted but their soil surface was bare was analyzed. When over 5 years passed after the completion of apartment complexes, over 20 mm of the soil was found to be stamped. The physicochemical properties of soil were also surveyed and the pH level was found to have been continuously high ever since the completion. The organic content in the surveyed soil was about 1/3 of the content in fertile soil, which means that additional fertilization is required. These results indicate that the stamped soil and the health of soil can be restored, when replanting plants in bare areas, by adding plans to improve soil, such as designing drain ways around the planted areas, transporting soil for the 50 cm depth of the ground and mixing organic matters such as chaff, and simply by planting groundcover plants in the lower part of tress and shrubs.

• Korean Journal of Organic Agriculture
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• v.14 no.2
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• pp.205-217
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• 2006

This research was carried out to investigate the effects of some organic materials such as rice straw, compost, hairy vetch, phosphate rock, magnesium lime powder and ash in the organic paddy fields, and also to develope the new technique for better soil management using described materials. The results are as follows; Height and tiller of rice plants were higher in chemical fertilizer than rice straw or compost, however, those of rice plants in hairy vetch-rice cropping system reached to chemical fertilizer. The Eh value of soil has decreased consecutively since on 30th, May because of the rising of soil temperature by an increase in the activity of microbes. As a result of measuring yield and yield components, there is not significant difference between treatment. The application of organic materials enriched the contents of available phosphorus, exchangible potassium and calcium in soil, and, also improved the physical properties such as pore space rates and bulk density. From the viewpoint of soil management technology in organic paddy fields, the application of rice straw or organic compost might cause the decrease of yield compared with conventional cultivation system, chemical fertilizer, however, the application of hairy vetch residues of soil compensated for growth and yield as well as improved the physicochemical property. Therefore, it is assumed that the cultivation of hairy vetch for winter season can be one of the useful methods for organic farming system.

• Korean Journal of Environmental Agriculture
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• v.42 no.4
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• pp.331-337
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• 2023

Physiological disorders in pear fruit are mainly caused by problems during the growing season, such as lack of calcium in the soil, poor drainage, low porosity, vigorous pruning, and excessive fruiting. In this study, soil physicochemical properties and leaf characteristics were analyzed in pear orchards in four regions of Korea where chlorosis symptoms occurred to determine the causes of chlorosis. The color of chlorotic leaves was diagnosed using the naked eye or SPAD and Hunter values. The soil of the chlorotic orchard had a significantly higher soil pH than that of the regular orchard. Although adequate soil depth was not significantly associated with chlorosis, combined with over-fertilization of the soil with lime, it could potentially impair plant iron uptake. Chlorotic leaves had significantly lower iron and calcium contents and significantly higher magnesium contents than those of regular leaves. Therefore, the intensive occurrence of chlorosis during secondary shoot development around June and July when it is hot and humid may be due to impaired iron and calcium absorption, leading to physiological disorders. To solve this problem, avoiding the over-application of lime and applying foliar fertilizers containing chelated iron is recommended.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.2 no.1
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• pp.33-40
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• 1969

1. Physicochemical properties of sea water and soil of Korean tidal flats densely populated with species of Mactra veneriformis, Cyclina sinensis, Meretrix lusoria, and Tapes philippinarum, were investigated in order to find out the index of environmental factors in marine bivalve culture. 2. The turbidity varied with the change in concentrations of organic matter, silicate, and the exchangeable copper in sea water. All of these concentrations in Inchon, Kunsan, and Hansando were higher than those in Yusoo. In the 5 areas investigated the lowest were ditected at Kangnung. 3. The minerals and organic matter content in sea water dia not vary significantly among the different bivalve beds. And it was presumed that the soil texture was one of the most important environmental factors for the density of the bivalves in tidelands. 4. The soil texture index of the different bivalve beds was obtained as follow: 5. There were no significant differences of pH, the exchangeable calcium, and the exchangeable copper contents of bottom soils in the 4 different bivalve beds. As important factors in these areas, it seems that the amount of chemical properties might not affect the distribution of bivalve species. 6. Among the 4 beds the soil organic matter content was highest at the T. philippinarum bed and varied with the total nitrogen content. 7. Among the different bivalve beds, it was significant that the water holding capacity and available phosphorus content were highest at the M. veneriformis bed.

• The Korean Journal of Pesticide Science
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• v.9 no.4
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• pp.316-329
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• 2005

Mobility of pesticides can be occurred by run-off and leachate or soil erosion. It is one of the most important factors for environmental contamination, particularly in steep sloped-land as Gangwon alpine region. In this study, the mobility of seven pesticides in different slopes and soil textures was investigated by simulated rainfall under controlled conditions. Simulated rainfall subjected to 60 mm $hr^{-1}$ was treated using rainfall simulator after 12 hr of pesticide treatment. Amounts of the pesticides were measured in run-off and leachate samples. The soil samples collected after rainfall from upper and lower parts and three different depths of sloped-plot were also analyzed. At result, all pesticides from the un-off samples collected from Taebaek(silty clay loam) and Heongseong(sandy loam) soils were detected maximum 96% within 60 minutes after first collection except carbendazim and cypermethrin which have the lowest water solubilities. From the leachate samples, a similar pattern was shown as run-off samples but amount of pesticides was lower than those of run-off samples. In soil samples, the order of the amount of pesticide residues was $0{\sim}5$ > $5{\sim}10$ > $10{\sim}15$ cm of soil depth and no pattern was shown in upper and lower, and different slopes. Comparing to mobility of pesticides in water and soil samples, pesticides in soil samples were higher than those of water samples in Taebaek soil. However, the results using Heongseong soils were in contrast to those of Taebaek soil. These results revealed that mobility of pesticides can be dependant mainly on soil textures and physicochemical properties of pesticides. Therefore, it can be suggested that selection of pesticides should be considered for soil texture and properties of pesticide in the alpine and sloped-land.