• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.4
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• pp.1-10
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• 2011

This study was conducted to compare the growth of Zoysia japonica depending on different soil treatments in Saemangeum sea dike, which is filled with dredged soil. Zoysia japonica was planted using sod-pitching method on the control plot. On plots which were treated with forest soil and soil improvement, Zoysia japonica seeds were sprayed mechanically. Sixteen months after planting, coverage rate, leaf length, leaf width, and root length were measured and analyzed. Also, three Zoysia japonica samples per plot were collected to analyze nutrient contents. Coverage rate was 100% in B treatment plot(dredged soil+$40kg/m^3$ soil improvement+forest soil), in C treatment plots (dredged soil+$60kg/m^3$ soil improvement+forest soil), and D treatment plots (dredged soil+$60kg/m^3$ soil improvement), while only 43% of the soil surface was covered with Zoysia japonica on control plots. The width of the leaf on C treatment plots (3.79mm) was the highest followed by D treatment (3.49mm), B treatment (2.40mm) and control plots (1.97mm). Leaf and root length of D treatment was 30.18cm and 13.18cm, which were highest among different treatments. The leaf length of D treatment was highest followed by C, B, and A treatments. The root length of D treatment was highest followed by C, A, and B treatments. The nitrogen and phosphate contents of the above ground part of Zoysia japonica were highest in C treatment, followed by D, B, and A treatments. The nitrogen and phosphate contents of the underground part of Zoysia japonica were highest in D treatment, followed by C, A, and B treatments. C and D treatments showed the best results in every aspect of grass growth. The results of this study could be used to identify the cost effective way to improve soil quality for soil surface fixation on reclaimed areas using grass species.

• Journal of Korea Foundry Society
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• v.15 no.3
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• pp.209-219
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• 1995

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2007.11a
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• pp.151-152
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• 2007

개량된 플라즈마 전해산화 기술(Advanced Plasma Electrolytic Oxidation; APEO)을 사용하여 마그네슘((Mg)기판표면을 경면처리한 후 내마모 특성을 조사하였다. 시편의 마찰계수 거동과 시간에 따른 마모깊이의 변화를 조사하여 APEO 처리 후 마모특성의 변화를 관찰하였다.

• Journal of the Korean Wood Science and Technology
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• v.34 no.1
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• pp.61-67
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• 2006

The purpose of this study was to develop soil conditioner using wood decay fungus. The effect of soil conditioner treated with SJ-28 fungus was tested by lettuce cultivation. Cultivating efficiency was investigated by the yield of lettuce. In the plot of soil conditioner treated with SJ-28 fungus (FPG) showed weight of lettuce leaves 4425 g of total yield which was greater than 2434 g shown in the control. Also the numbers of actinomyces and fungi were increased in the plot of soil conditioner treated with SJ-28 fungus (FPG), beneficial for soil. The number of bacteria showed decrease in FPG plot. FPG showed possibility as a soil conditioner.

• Journal of the Korean GEO-environmental Society
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• v.20 no.5
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• pp.39-46
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• 2019

Most of the soil used for reclamation is marine clay generated from dredging construction.The soft ground made of dredged clay has high water content and high compressibility, so the bearing capacity of the ground is very weak and it is difficult to enter the ground improvement equipment. Therefore, surface hardening treatment method is used to enter equipment prior to full-scale civil engineering work, and stabilizer is mainly used for cement series. Cement-based stabilizers have the advantage of improving the ground in a short period of time and have excellent economic efficiency, but they are disadvantageous in that they cause environmental problems due to leaching of heavy metals such as hexavalent chromium. In this study, environmental effects evaluation of dredged clay mixed with normal portland cement and environmentally friendly stabilizer was evaluated, and uniaxial compressive strength test and indoor model test were conducted to confirm the bearing capacity characteristics of the solidified layer.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2008.09a
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• pp.77-89
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• 2008

본 연구는 유기흑염소 생산에 기초적인 자료를 얻고자 유형이 다른 산지 초지에 방목하여 흑염소의 발육과 육질에 미치는 영향을 조사하였다. 공시축은 흑염소 40두를 4처리구(개량목초구, 유기목초구, 산야초구, 수엽류구)로 나누어 처리구당 10두씩 공시하여 2007년 5월 15일부터 2007년 11월 5일까지 174일간 농촌진흥청 축산과학원 가축유전자원시험장 방목지에서 수행하였다. 그 결과는 다음과 같다. 일당증체량은 개량목초구가 다른 시험구 보다 유의하게 높았다(p<0.05). 도체율은 개량목초구와 유기목초구가 산야초구와 수엽류구 보다 유의하게 높게 나타났다(p<0.05). 정육율은 개량목초구가 유의하게 높게 나타났다(p<0.05). 흑염소 고기의 조지방은 산야초구가 높은 경향이었다. 고기의 리놀레산과 리놀렌산은 개량목초구 보다 유기목초구, 산야초 및 수엽류구가 높은 경향이었으며, 아라키돈산은 산야초와 수엽류구가 다른 시험구 보다 높은 경향으로 나타났다. 전단력은 산야초구가 낮은 경향이었으며, 관능검사 결과 중 다즙성과 연도는 유기목초구와 산야초구가, 풍미는 산야초구와 수엽류구가 우수한 경향으로 나타났다. 이상의 결과를 종합해 보면, 산지에 방목 사육된 유기흑염소는 다소 생산성과 도체특성은 낮으나 육질 및 물리적 특성이 우수한 경향으로 나타나 고품질 유기축산물 생산으로 농가소득 증대뿐만이 아니라 소비자 요구충족에도 가능성이 높은 것으로 기대된다.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.123-131
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• 2009

The study decided the improvement depth of soft ground of deep mixing method through 2 and 3 dimension finite element method and following results were acquired. 1. 2 dimension analysis shows settlement 10% more estimated than 3 dimension analysis. 2. When the rate of replacement is under 5%, the settlement sharply increased. 3. The most economical design for the levee was decided 3.0m for width direction, 6.0m for length direction and 8.0m for improvement depth. 4. When the soft ground is developed through deep mixing method, the decision of improvement should be decided through 3 dimension analysis than 2 dimension analysis.

• 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.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.3
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• pp.242-247
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• 1997

This study was conducted to investigate the combined effects of oyster shell, fly ash and gypsum on rice yield and quality. The four treatments of soil amelioration were oyster shell 4, fly ash 80, fly ash 56 + gypsum 24 and oyster shell 0.8 + fly ash 40 + gypsum 24 ton/ha. Rice yield were in the order of oyster shell, fly ash and control plats. The pH, EC values and OM, Ca, $SO_4$, moisture contents of the top-soil after rice harvesting in soil amelioration treatments were increased, while Mg, Na, Fe, Zn and Al were decreased than those of control. Rice quality was the best in the fly ash plat due to lower T-N and higher Mg/K ratio.

• Ecology and Resilient Infrastructure
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• v.4 no.3
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• pp.180-185
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• 2017

Restoration of min-impacted arable land is often performed through stabilization of trace elements by amendment treatment combined with (clean) soil covering on the surface. Recently, soil loss problem from sloping remediated agricultural lands has risen as an emerging concern. In this study, efficacy of aggregation formation was assessed by single and binary treatments of four potential amendments (bentonite, lime, organic matter, and steel slag) applied on three cover soils having different clay contents (9.4, 14.7, and 21.2% for A, B, and C soils respectively). In results of single treatments, 5% organic matter for A soil and 5% lime for B and C soils were found most effective for the aggregation formation compared to the respective controls (without amendments). Among nine binary treatments, 3% organic matter + 1% lime for A soil and 1% organic matter + 3% lime for both B and C soils led to the highest formation of aggregation (30.4, 25.0, and 36.5% for A, B, and C soils). For a site-application, the soil erodibility difference between the cover soils (0.045, 0.051, and 0.054 for A, B, and C soils, respectively) and the national average of arable land (0.032) was assumed to be compensated by amendment addition, which is equivalent to 29.1% aggregation formation. To achieve the aggregation goal, 5% lime for A and B soils and 3% lime for C soil were best in the consideration of benefit/cost, thereby effectively and economically reducing soil loss from sloping remediation site. Soil alkalinity induced by lime treatment was not considered in this work.