• Journal of Environmental Policy
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• v.4 no.1
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• pp.93-111
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• 2005

Defining soil quality in scopes and applications is one of the prerequisite for the sustainable management of soil environment to orient researches, strategies and policies. However, definition of soil quality is controversial depending upon a viewpoint of soil science or soil environment. Soil quality can be, irrespective of the disciplines, defined as the capacity of a soil to function within ecosystem boundaries to sustain biological productivity, maintain environmental quality and promote plant and animal health. Common to all of the soil quality concepts can be summarized as the capacity of soil to function effectively at present and in the future. The OECD includes soil quality as one of the agri-environment indicators. This article intends to i) summarize the current soil quality research, and ii) provide information on protocol of soil quality assessment. A framework for soil quality was divided into three steps: indicator selection as minimum data set (MDS), scoring of the selected indicators, and integration of scores into soil quality index. Korean government suggested possible physical and chemical indicators such as bulk density and organic matter for paddy and upland soils to OECD. The framework of soil quality assessment is not yet implemented in Korea. Countries such as USA, Canada and New Zealand have constructed the framework on soil quality assessment and developed a user-friendly version of soil quality assessment tools to evaluate the integrated effects of various soil management practices. The protocol provided in this review might help policymakers, scientists, and administrators improve awareness about soil quality and understand the way of soil environment management.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.3
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• pp.224-231
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• 1984

Four kinds of soil conditioners, such as red earth, clayey tidal deposit, silty tidal deposit and tertiary deposit were evaluated for the rice growth and for the effectiveness of soil improvement in sandy paddy soil (Gangseo series) whose percolation and nutrient leaching are usually severe. Experiment was conducted at the farmer's field in Hackpo Ri, Bugog Myeon, Changyeong Gun, Gyeong Nam Province for two years (1980-1981) with using two rice varieties, Milyang 42 for 1980 and cheongcheongbyeo for 1981. For both experimental years, the grain yields were increased on the plots that were treated with soil conditioners compared with nontreated plot. The increase in grain yield was particularly high on the plots treated with clayey tidal deposit and teritary deposit. The dry weight of the plant and the uptake amount of inorganic ingredient tended to increase on the plots of clayey tidal deposit and tertiary deposit during whole rice growing season because of the residual effect of soil conditioners in the second experimental year. Cation exchange capacity, available silicate, exchangeable potassium and active iron was increased by the treatment with the soil conditoners. Especially cation exchange capacity was highest in the tertiary deposit treatment plot. Aggregation content and plastic index were increased for the all treatment plots with soil conditioner, however, hydraulic conductivity was conspicuously decreased by the tertiary deposit and clayey tidal deposit treatments.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.207-211
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• 2004

Evaluation of wind erodibility for the Saemangeum Reclamation Project area based on the wind erosion equation, WEQ, was attempted. Climatic factor was calculated with the climatic data for the Kunsan area, and soil erodibility factor was evaluated with the 108 soil samples collected from the project area. The soil erodibility evaluated from the non erodible aggregate percentage greater than 0.84 mm for the soil samples collected was $204.1Mg\;ha^{-1}\;yr^{-1}$ ranged from 50.08 to $642.37ha^{-1}\;yr^{-1}$. The annual climate factor based on the meteorological data in Kunsan was 3.67. The average amount of wind erosion with climate factor C from the climatic data from Kunsan and soil erodibility factor l from the soil in the project area was 7.49 Mg $ha^{-1}$ $yr^{-1}$ ranged from 1.84 Mg $ha^{-1}$ $yr^{-1}$ for silty clay loam soil to 23.57 Mg $ha^{-1}$ $yr^{-1}$ for sandy soil. The intensive wind erosion control should be needed for friable sand and loamy sand soils in the area.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.1
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• pp.1-6
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• 1983

The results of COLE(Coefficient of Linear Extensibility) measurement on various paddy soils in Korea are summarized as follows; 1. The COLE values of paddy soil in Korea varied from 0.024 to 0.094 in the surface soil while in the sub-surface soils those were ranging from 0.022 to 0.115. The poorer the relative drainage and the finer the texture caused, the greater the COLE values. 2. The matured clayey soils on fluvio-marine plains and local alluvium derived from the Tertiary materials have COLE values more than 0.09 which is demonstrated that the necessity of COLE measurement throughout profiles so that could be considered the characteristic in the characteristic of those soils. 3. The clay content has the highest positive correlation (r=0.81~0.76) values. The content of organic matter, water content at 1/3 bar, Atterberg limits, water stable aggregate etc. also have significant positive correlation with COLE values while the context of sand and silt show negative correlation. 4. Although the COLE values measured on horizontal linear bases were slightly greater than those measured on volume bases practicability was for granted. For more accurate measurement of COLE, it is reasonable to have the average values of COLE calculated from the horizontal and vertical bases.

• Journal of Korean Society of Rural Planning
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• v.11 no.4 s.29
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• pp.93-98
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• 2005

A aggregate size distribution of soils is an important in successful crop production in reclaimed tidelands. The aggregate size distribution for this study were determined of 0.1mm, 0.25mm, 0.5mm, 1.0mm, and 2.0mm by wet sieving method. Agricultural activity, period of reclamation showed significant effects on aggregate size distribution in reclaimed tidelands. Aggregate MWD was greater in SS and KH(above 1.0m) than in YSG, GHD, SMG, and DH(below 0.5mm) reclaimed tidelands and tidelands. The percentage of aggregates less than < 2mm for SMG, GHD, and SM reclaimed tidelands and tidelands were ranged 8.9%, 36.7%, and 38.0%, respectively. The percentage of > 0.1mm aggregates for SMG, GHD, and SM reclaimed tidelands were ranged 9.0%, 26.0%, and 48.9%, respectively. Results indicated that aggregate size distribution of reclaimed tidelands and tidelands under various agricultural systems vary with reclamation period and soil type.

• Korean Journal of Soil Science and Fertilizer
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• v.26 no.3
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• pp.151-154
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• 1993

The magnitute of CEC of the reaction product which was produced by the treatment of the natural zeolite power(CEC : 67me/100g) with 3N-NaOH at $80^{\circ}C$ for 30 hours was determined to be about 260me/100g, which was the highest value in all reaction products. By the NaOH-treatment the contents of major clay minerals in natural zeolite was shown to be decreased and it is apparent that new phillipsite was synthesized. Furthermore it is interesting that the phillipsite contents was increased with longer reaction time and higher temperature. After 30 hours treatment the dorminant clay mineral in the reaction product was found to be phillipsite.

• Journal of Ginseng Research
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• v.13 no.1
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• pp.84-91
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• 1989

This study was conducted to Investigate the effects of physico-chemical soil properties on the growth and yield of ginseng. 1 In the field survey, the yields of 6 year old ginseng were 2.46 Kg/3.3$m^2$, 2.13 Kg/3.3$m^2$, 1.44 Kg/3.3 $m^2$ in clay loam, loam and sandy loam soils, respectively 2. The missing plant rate for il year old ginseng were 33.6% and 51.6% in clay loam and sandy loam soils, respectively : the stem length and stem diameter of ginseng plants in sandy loam soil were smaller than those in clay loam soil. 3. Soil aggregation and porosity we're slightly higher in 6 year old ginseng fields than in 2 year ones. 4. Inorganic-N increased in 2 year and 3 year old ginseng fields reaching up to 100-120ppm, however it 1 decreased to 75 ppm, 34 ppm and 25 ppm in 4, 5 and 6 year old ginseng fields, respectively, It varied 1 more greatly in sandy loam soil than in clay loam. 5. The $P_2O_5$, K, Ca, and Mg contents differed little with plant age. Sandy loam had high N and $P_2O_5$ contents but low cation contents. 6. The yield of 6 year old ginseng fields were significantly correlated with clay contents and porosity. The missing Plant rate of 6 year old ginseng had a positive correlations with sand. and N contents.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.2
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• pp.90-95
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• 1984

To improve the physico-mechanical characteristics of heavy clayey paddy soils(Hwadong series) on Diluvial terrace after application of fine sand and briquette ashes, barley and rice were cultivated for 2 years. The influences of sand and briquette ashes on soil properties and on the crops were summarized as follows: 1. Application of the adding materials could not affect the yield of rice but barley yields were increased significantly about 18-19% in the plots of sand 100t/10a(clay 15% adjusted) and in the plots of briquette ashes. 2. The porosity and the content of water stable aggregates were decreased in the plots of sand and briquette ash adding. The chemical properties were slightly decreased in the plots of sands while the contents of av. $SiO_2$: and extr K were increased in the plots of briquette ashes. 3. Soil mechanical properties such as cone penetration resistance, shearing resistance and plastic index etc. were decreased while the friction resistance increased in the plots of sand and briquette ash treatments. Consequently, the adaptability to mechanization was increased. 4. The content of rice roots in subsoils (10-20cm) were increased in the plots of sand and briquette ash treatments.

• Korean Journal of Environmental Agriculture
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• v.28 no.1
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• pp.25-31
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• 2009

The effect of application of gypsum (G), popped rice hulls (PRH), and zeolite (Z) in exchangeable cations concentrations of reclaimed tideland soil in Kyehwado was investigated for 3 years from 2004 to 2006 in a pot experiment with bermuda grass (Cynodon dactylon). Treatments with three soil conditioner and with three applications were established with three replications; G1 (1,550 kg $10a^{-1}$), G2 (3,100), and G3 (6,200) for gypsum, H1 (1,000), H2 (2,000), and H3 (3,000) for PRH, and HZ1 (200), HZ2 (400), and HZ3 (800) for co-application of zeolite with PRH at the 1,500 kg $10a^{-1}$. At 60, 90, 120 days after treatment (DAT), exchangeable cations ($K^+$, $Na^+$, $Mg^{2+}$, and $Ca^{2+}$) were analyzed Gypsum application significantly decreased $k^+$, $Na^+$, $Mg^{2+}$ in the soil probably due to exchange and subsequent leaching of these cations by $Ca^{2+}$ from the gypsum applied. Overall, $K^+$ concentration was gradually decreased by continuous application of soil conditioners and was in the order of 2004>2005>2006 regardless of the kinds and application rate of soil conditioners. Comparing $K^+$ concentrations among the soil conditioners in the same year, its concentration was in the order of gypsum$Na^+$ concentration; i.e. $Na^+$ concentration was in the order of gypsum$\ll$PRH$Mg^{2+}$ also showed a similar pattern to $Na^+$. Gypsum application significantly increased $Ca^{2+}$ concentration and in the gypsum treated soil $Ca^{2+}$ concentration increased with years.

• Economic and Environmental Geology
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• v.45 no.2
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• pp.121-135
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• 2012

Soil dispersion and heavy metal leaching with two heavy metal-contaminated soils were studied to derive the optimal dispersion condition in the course of developing the remedial technology using magnetic separation. The dispersion solutions of pyrophosphate, hexametaphosphate, orthophosphate and sodium dodecylsulfate (SDS) at 1 - 200 mM and the pH of solutions was adjusted to be 9 - 12 with NaOH. The clay content of suspension as an indicator of dispersion rate and the heavy metal concentration of the solution were tested at the different pHs and concentrations of the dispersion solution during the experiment. The dispersion rate increased with increasing the pH and dispersion agent concentration of the solution. The dispersion efficiency of the agents showed as follows: pyrophosphate > hexametaphosphate > SDS > orthophosphate. Arsenic leaching was sharply increased at 50 mM of phosphates and 100 mM of SDS. The adsorption of $OH^-$, phosphates and dodecysulfate on the surface of Fe- and Mn-oxides and soil organic matter and the broken edge of clay mineral might decrease the surface charge and might increase the repulsion force among soil particles. The competition between arsenic and $OH^-$, phosphates and dodecylsulfate for the adsorption site of soil particles might induce the arsenic leaching. The dispersion and heavy metal leaching data indicate that pH 11 and 10 mM pyrophosphate is the optimum dispersion solution for maximizing dispersion and minimizing heavy metal leaching.