• Korean Journal of Soil Science and Fertilizer
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• v.34 no.1
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• pp.1-7
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• 2001

Total upland area for cultivating the vegetable crops in the Alpine soils of Northeastern South Korea has been extending its limit to meet the increasing demand of vegetable food in recent decades. About 70% of these alpine soils are located in over 7% of the slope and most of vegetable crops have been cultivated intensively without practicing the best management systems. Thus, soil erosion and continuous cropping system have degenerated the soil fertility and shown detrimental effects on water quality. We initiated an intensive and extensive investigation to characterize the fertility problems encountered in these uplands. Objectives of this paper were to characterize the fertility status in the Alpine soils cultivated with vegetable crops for many years and to provide the recommendations for adequate soil management measures including fertilization and erosion control. Soils in general have good drainage with textural classes of loam or sandy loam. Their topographical characteristics tended to lead them to shallow plow layers, and the steepness of the terrain created erosion hazard. Of the soils examined, about 11% of uplands over 30% gradient was found in need of an urgent reforestation. A high content of gravel and firm hardness of soil attributed to inhibit the utilization of farm machinery and plant-root development. The average soil pH 5.6 was slightly low relative to pH 5.70 of the national average. Organic matter content was high compared with 2.0% of national average, but decreased with the prolonged cultivation periods. Available $P_2O_5$ concentration was unusually high due to the consequence of over dose application with chemical and organic fertilizers. Exchangeable cations as Ca, Mg, and K were appeared to be decreased in these regions with prolonging the cultivation periods. There were no significant differences in cation exchange capacity (CEC) and electrical conductivity (EC) among locations. Heavy metal contents were mostly lower than the threshold of danger level designated by Soil Environment Conservation Law of South Korea. Results indicated that a proper countermeasure and the best management practice should be immediately implemented to conserve the top soil and fertility in the Alpine regions.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1027-1034
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• 2011

In order to provide the basic information on the agricultural environment in Daegwallyeong Highland, the characters of weather, water, and soil quality were investigated. The meteorological characteristics was monitored by automatic weather system (AWS) at 17 sites. The quality of water for samples were collected monthly at 24 sites depending on landuse style. Soil samples were collected from a forest, grassland, and the major vegetable cultivation areas such as potato, carrot, Chinese cabbage, onion, head lettuce, and welsh onion field. The weather showed the mountain climate, and the average yearly temperature is $6.4^{\circ}C$, the average temperature in January is $-7.6^{\circ}C$ and the average temperature in July is $19.1^{\circ}C$, and the change of temperature on the districts of Daegwallyeong is severe. The yearly record of precipitation shows 1717.2 mm. The water quality of crop field was worse than forest or grassland in Daewallyeong highland. In 2005, annual T-N, T-P, SS distribution of Chinese cabbage field showed 7.4~11.3, 0.061~0.1, and $3.0{\sim}53.0mg\;L^{-1}$. The potato field showed 3.1~7.2, 0.019~0.056 and $0.5{\sim}3.0mg\;L^{-1}$, respectively. Being compared of water quality between potato field and chinese cabbage field, it showed that the water quality of Chinese cabbage field was worse than potato field. On farming, the soil of crop cultivation showed pH 5.6 to 6.8, $18.0{\sim}42.4g\;kg^{-1}$ of OM, $316{\sim}658mg\;kg^{-1}$ of Avail. $P_2O_5$. The content of cations showed $0.41{\sim}0.88cmol_c\;kg^{-1}$ of Exch. K, $3.73{\sim}7.07cmol_c\;kg^{-1}$ of Exch. Ca and $1.17{\sim}1.90cmol_c\;kg^{-1}$ of Exch. Mg.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.502-509
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• 2011

It is important to determine optimum soil covering depths for tree survival and growth because soil covering depths for establishing tree planting bases in coastal reclaimed lands are related to the costs for soil collection, transportation and land reclamation. The objectives of this study were carried out to determine optimum soil covering depths for the normal growth of planted trees in a coastal reclaimed land. The study sites were located in Asan National Industrial Complex in Pyeongtaek City, Gyeonggi-do. Four tree species (Pinus thunbergii, Chamaecyparis pisifera, Zelkova serrata, Quercus acutissima) with one hundred eighty trees of each species were planted in various depths of soil covering (no soil covering, 0.5 m, 1.5 m, 2.0 m soil covering treatments) on April 1998, and the tree growth patterns were measured on September 2000. The change of soil properties, tree mortality rate, root collar diameter and height growth were measured from each soil covering depth treatment on September 2000. Soil pH, EC, exchangeable cations ($K^+$, $Na^+$, $Ca^{2+}$, $Mg^{2+}$), anion $Cl^-$, and base saturation increased with decreased soil covering depths. The mortality rates of tree species showed decreased with increased soil covering depths. The height growth of tree species increased with increased soil covering depths. Height growth of Pinus thunbergii was significantly different between the soil covering depth below 0.5m and other three covering depths, while the growth of other species (C. pisifera, Z. serrata, Q. acutissima) was significantly higher in soil covering depths below 1.5 m than in other soil covering depth treatments. The root collar diameter growth of all tree species showed increasing trends with increased soil covering depths. It is recommended to cover the soil depths above 1.5 m to decrease mortality and to stimulate the tree growth of C. pisifera, Z. serrata and Q. acutissima, while P. thunbergii which is a salt tolerate species could be planted in the 1.0 m soil covering depth.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.361-367
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• 2011

Soil fertility of alpine soils in Gangwon-Do has been deteriorating because of heavy input of chemical fertilizers for intensive crop production. To reduce application of chemical fertilizers, use of livestock manure compost in alpine soils increases consistently. Soil loss and runoff due to heavy rainfall in alpine area cause nutrient loss from soil, and subsequently pollute stream water. Therefore, the objective of this study was to assess nutrient efficiency and loss in Chinese cabbage cultivated soil with different livestock manure composts in several slopes. As control, chemical fertilizer was applied at the rate of $250-78-168kg\;ha^{-1}$ for $N-P_2O_5-K_2O$. Each pig-and chicken manure compost was applied at the rate of $10MT\;ha^{-1}$. Chemical fertilizer + chicken manure compost was applied as same rate. Four treatments was practiced in 5, 20, and 35% filed slopes, respectively. We monitored the amounts of soil loss and runoff water after rainfalls, and we also analyzed the contents of nutrients in soil and runoff water through lysimeter installed in alpine agricultural institute in Gangwon-Do. T-N loss due to soil loss was much greater with increasing filed slops rather than different fertilizer treatments. T-N loss has positive relationship with field slopes, which showing soil loss (MT/ha) = 1.66 slopes (%) - 3.5 ($r^2$ = 0.99). Available phosphate and exchangeable cations showed similar tendency with increasing slopes. T-N and T-P losses caused by runoff water were highest in chemical fertilizer (NPK) + chicken manure compost treated plot, while lowest in chemical fertilizer treatment. T-N contents (2.13, 1.95%) in chinese cabbage treated either pig and chicken manure composts compared to that (2.65%) of chemical fertilizer were significantly less. This could be resulted from much greater T-N loss in soil treated with pig and chicken manure composts.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.945-953
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• 2010

This study was conducted to evaluate the effect of swine liquid manure (SLM) on rice grown in Yeonggwang-gun in 2008. The treatments consisted of SLM and chemical fertilizer (CF) based on the recommended amount of nitrogen (11 kg N $10a^{-1}$). The Total N content of the SLM used was 2,881 mg $L^{-1}$. Plant height at the early stage of growth and tiller number were not significantly different between plots applied with swine liquid manure and those with chemical fertilizer in all areas. Plant height at the later stage of growth, lodging and yield were not significantly different between plots applied with swine liquid manure and those with chemical fertilizer in three areas (Baeksu, Gunnam, Beopseong). Plant height at the later stage of growth, as well as lodging were higher in SLM plots than in chemically fertilized plots in Yeonggwang and Yeomsan. However, grain yield was lower in SLM plots than in chemically fertilized plots in these areas. Soil organic matter content and exchangeable cations increased in the swine liquid manure applied plots. Moreover, heavy metal content did not increase in the plots treated with swine liquid manure. Further research to determine the suitable rate of swine liquid manure is needed to reduce lodging damage and to increase the yield and quality of rice.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.5
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• pp.371-378
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• 2009

This study was carried out to investigate the improvement effect of soil fertility by incorporation of GMC(green manure crops) at rice cropping after cultivation GMC such as the barley for alternative rye in paddy field over the past two years(2006~2007). Plots, which consisted of incorporation time of GMC as rye; heading stage, barley; heading stage, heading stage of rye and 10days after heading stage were divided by amount of applied rates; standard fertilizer fertilization, diagnosis fertilization and non-fertilization. we investigated change of soil physico-chemical properties, degree of decomposition on GMC in soil, growth and yield potential. The obtained results were summarized as follows. The fresh weight of GMC at incorporation time on heading stage of rye, heading stage and 10days after heading stage of barley were $2,715,\;2,352,\;2,867kg\;10a^{-1}$ respectively. Content of total nitrogen at three incorporation times was 1.31, 1.46, 1.38% and the C/N ratio were 33.4, 28.7, and 34.6, respectively. Some soil physical properties, such as soil hardness and bulk density tended to decrease with incorporation of GMC, while surface soil depth and porosity were increased. Some soil chemical properties, such as content of exchangeable cations and cation exchangeable capasity(CEC) were increased with incorporation of GMC compared with before experiment. Rice yields was increased 3~9% in diagnosis application plots on application of barley compared with control($559kg\;10a^{-1}$) and incorporation of barley caused to improve perfect kernel ratio 73.6~78.7% in appearance characteristics of brown rice compared with cotrol(73.0%). It was found that incorporation with 10days after heading stage of barley was more effective to reduce chemical nitrogen fertilizer and to improve soil fertility.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.852-857
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• 2010

This study was performed to explore the effect of the clay mineral illite on the improvement of bed soil and plant growth. Red pepper (Capsicum annuum L.) was used as a model vegetable crop. The experiment was performed during the whole six weeks in the glass house of the Chungbuk National University. Its seedlings were cultivated in the bed soil normally used for horticultural purpose. Of the seedlings cultured, the healthy and regular size of seed were selected and cultivated in the pots. They were treated with two forms of illite, particulate (PA) and powder (PW), at the following application rates: standard application[P1 (PA1, PW1), 1:20 (w/w)], two times[P2 (PA2, PW2), 1:10 (w/w)], and four times[P4 (PA4, PW4), 1:5 (w/w)] of standard application. Untreatment (P0) was used as a control pot. At six weeks of cultivation, their growth lengths were correspondingly increased as the application rate was increased ranging from P0, P1, P2, and to P4. Their growth length was a little greater on the application of powder illite (PW) than on the particulate illite (PA). Based on the plant analysis for the root, leaf, stem of red pepper, the uptake amounts of K, Ca, and Mg, were correspondingly increased, as the application rate was increased ranging from P0, P1, P2, and to P4, respectively. At the same application rate, their amounts taken up in the respective parts were higher on the application of PW illite than on the PA one. Especially the amounts of Ca and Mg were higher in the stem, leaf than root. Consequently, it appears that the illite treatment, especially, PW form of illite, enhance the growth of red pepper in the glass house during the whole six weeks of experiment.

• Korean Journal of Remote Sensing
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• v.37 no.6_2
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• pp.1859-1867
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• 2021

This study investigated seasonal characteristics of the particulate matter (PM) in the atmosphere and rainwater quality in Busan, South Korea, and evaluated the seasonal effect of PM₁₀ concentration in the atmosphere on the rainwater quality using multivariate statistical analysis. The concentration of PM in the atmosphere and meteorological observations(daily precipitation amount and rainfall intensity) are obtained from automatic weather systems (AWS) by the Korea Meteorological Administration (KMA) from March 2020 to August 2020. Rainwater samples (n = 216, 13 rain events) were continuously collected from the beginning of the precipitation using the rainwater collecting device at Pukyong National University. The samples were analyzed for pH, EC (electrical conductivity), water-soluble cations(Na⁺, Mg²⁺, K⁺, Ca²⁺, and NH₄⁺), and anions(Cl^-, NO₃^-, and SO₄^2-). The concentration of PM₁₀ in the atmosphere was steadily measured before and after the precipitation with a custom-built PM sensor node. The measured data were analyzed using principal component analysis (PCA) and Pearson correlation analysis to identify relationships between the concentration of PM₁₀ in the atmosphere and rainwater quality. In spring, the daily average concentration of PM₁₀ (34.11 ㎍/m³) and PM_2.5 (19.23 ㎍/m³) in the atmosphere were relatively high, while the value of daily precipitation amount and rainfall intensity were relatively low. In addition, the concentration of PM₁₀ in the atmosphere showed a significant positive correlation with the concentration of water-soluble ions (r = 0.99) and EC (r = 0.95) and a negative correlation with the pH (r = -0.84) of rainwater samples. In summer, the daily average concentration of PM₁₀ (27.79 ㎍/m³) and PM_2.5 (17.41 ㎍/m³) in the atmosphere were relatively low, and the maximum rainfall intensity was 81.6 mm/h, recording a large amount of rain for a long time. The results indicated that there was no statistically significant correlation between the concentration of PM₁₀ in the atmosphere and rainwater quality in summer.

• Korean Journal of Mineralogy and Petrology
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• v.34 no.3
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• pp.157-167
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• 2021

Lead (Pb) is one of the key trace elements, exhibiting a peculiar partitioning behavior into silicate melts in contact with minerals. Partitioning behaviors of Pb between silicate mineral and melt have been known to depend on melt composition and thus, the atomic structures of corresponding silicate liquids. Despite the importance, detailed structural studies of Pb-bearing silicate melts are still lacking due to experimental difficulties. Here, we explored the effect of lead content on the atomic structures, particularly the evolution of silicate networks in Pb-bearing sodium metasilicate ([(PbO)_x(Na₂O)_1-x]·SiO₂) glasses as a model system for trace metal bearing natural silicate melts, using ²⁹Si solid-state nuclear magnetic resonance (NMR) spectroscopy. As the PbO content increases, the ²⁹Si peak widths increase, and the maximum peak positions shift from -76.2, -77.8, -80.3, -81.5, -84.6, to -87.7 ppm with increasing PbO contents of 0, 0.25, 0.5, 0.67, 0.86, and 1, respectively. The ²⁹Si MAS NMR spectra for the glasses were simulated with Gaussian functions for Qⁿ species (SiO₄ tetrahedra with n BOs) for providing quantitative resolution. The simulation results reveal the evolution of each Qⁿ species with varying PbO content. Na-endmember Na₂SiO₃ glass consists of predominant Q² species together with equal proportions of Q¹ and Q³. As Pb replaces Na, the fraction of Q² species tends to decrease, while those for Q¹ and Q³ species increase indicating an increase in disproportionation among Qⁿ species. Simulation results on the ²⁹Si NMR spectrum showed increases in structural disorder and chemical disorder as evidenced by an increase in disproportionation factor with an increase in average cation field strengths of the network modifying cations. Changes in the topological and configurational disorder of the model silicate melt by Pb imply an intrinsic origin of macroscopic properties such as element partitioning behavior.

• Korean Journal of Environment and Ecology
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• v.33 no.4
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• pp.453-461
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• 2019

This study was conducted to monitor the soil characteristics and growth of Pinus densiflora and to determine the effect of soil characteristics on growth rate five years after an ecological restoration project in Baekdudaegan ridge including Ihwaryeong, Yuksimnyeong, and Beoljae sites. The ecological restoration project was executed with the forest of P. densiflora in 2012-2013. In April 2018, we collected soil samples from each site and measured the height and the diameter at breach height (DBH) of P. densiflora. Although there was no significant change of soil pH compared to the early stage of restoration (one year after the project), it was high in Ihwaryeong, and Beoljae with values of 7.7 and 6.4, respectively. Also, the organic matter decreased by 70-80%, and the available phosphorus (P) was unchanged in three restoration sites. The decreased organic matter can be attributed to restriction of inflow and thus decomposition of litter in the early stage after the restoration. The tree height growth rate ($m\;yr^{-1}$) of P. densiflora in Yuksimnyeong was the highest at 1.02, followed by Beolja at 0.75 and Ihwaryeong at 0.17. The height growth rate showed negative relationships with soil pH and cations, including Na and Ca concentrations and a positive relationship with available phosphate. The low growth rate in the Ihwaryeong site, in particular, might result from the poor nutrient availability due to high soil pH and the decrease in water absorption into the root due to high Na and Ca concentrations. The substantial reduction of organic matter after five years indicates that the need for soil improvement using chemical fertilizer and biochar.