• Title/Summary/Keyword: plastic silt

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Effect of long-term organic matter application on physico-chemical properties in rice paddy soil -2. The effect of some physical properties of paddy field by the long-term application of rice straw and compost (논토양(土壤)의 이화학적(理化學的) 성질(性質)에 미치는 유기물(有機物)의 연용효과(蓮用效果) -II. 생고(生藁) 및 퇴비(堆肥) 연용(蓮用)이 논토양(土壤)의 몇가지 물리적(物理的) 성질(性質)에 미치는 영향(影響))

  • Yoo, Chul-Hyun;Kim, Jong-Gu;Park, Keong-Ho;Kim, Seong-Jo
    • Korean Journal of Soil Science and Fertilizer
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    • v.21 no.4
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    • pp.373-379
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    • 1988
  • This experiment was carried out to investigate the effects of long-term applications of rice straw and compost on the physical and mechanical properties of paddy fields and the yearly variation of rice yield in Fluvio-Marine plain of Jeonbug series. Amounts of rice straw and compost applied in this experiment were 500kg/10a, 1,000kg/10a respectively, and the nitrogen levels were 0, 15 and 20kg/10a. This experiment were continued for 9 years from 1979 to 1987. The results are summarized as follows: 1. Clay and silt ratios were decreased but versa in sand ratio, by the long-term application of rice straw and compost. 2. Bulk density in the long-term application of organic matter was lower in surface soil of non-application than nitrogen application (15kg/10a) and in rice straw than compost. 3. Solid ratio went down, but liquid and gaseous ratio went up especially, by organic matter application liquid ratio were increased by compost and gaseous ratio were increased by in rice straw. 4. Aggregates of bigger than 2mm were increased by long-term application of organic matter, and the effects was better in rice straw than compost. Accumulative aggregate of 2mm was 66.5% in nitrogen of 15kg/ 10a with rice straw, which showed the increase of 9.1% in comparison with the non-application of nitrogen and organic matter. 5. Liquid limit, plastic limit and plastic index were high in order of rice straw, compost and control, and liquid index was lower in compost than in rice straw. 6. Cole value was higher in vertical than horizontal and highest in the application of rice straw with nitrogen of 15kg/10a. Cone and shearing resistance were lowest in the application of rice straw with nitrogen. In total vertical pressure friction was higher in the long-term application of organic matter than control. 7. The change of yield index was higher in the long-term application of compost than rice straw in non-nitrogen and it showed the yearly competitive variation between the long-term application of compost and rice straw in nitrogen of 10kg/10a. In nitrogen application of 20kg/10a, it was increased from 6th year by rice straw application.

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The Development and Characteristics of Diluvial Soils on the Catena (홍적층(洪積層) Catena에서 토양(土壤)의 발달(發達)과 특성(特性))

  • Rim, Sang-Kyu;Choi, Jyung
    • Korean Journal of Soil Science and Fertilizer
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    • v.17 no.3
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    • pp.200-206
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    • 1984
  • This study was conducted to examine the morphological, physical and chemical characteristics of the Bancheon, Gopyeong, Hwadong and Deogpyeong series derived from diluvium in Korea. The results were as follows. 1. The sequence of the Bancheon, Gopyeong, Hwadong and Deogpyeong series consists of the soil catena. Thus, the Bancheon and Gopyeong series are weil drained, the Hwadong and Deogpyeong series moderately well drained due to the influence of topography and irrigation water. 2. The surface soils of the Bancheon and Gopyeong series are yellowish red, dark yellowish brown fine silty texture and the subsoils are yellowish red, red and strong brown fine clayey with moderate to strong angular blocky or subangular blocky structure with clayey cutans on the structural face. The surface soils of the Hwadong and Deogpyeong series are dark grayish brown, grayish brown fine silty texture and the subsoils are strong brown, light olive brown and brownish yellow fine silty or fine clayey with moderate to strong prismatic, angular blocky or subangular blocky structure with clayey cutans on the structural face. The consistences of all the subsoil horizons are extremely compact and hard, whereas sticky and plastic when wet. 3. The lower the topography, the higher the silt/clay ratio, soil reaction, organic matter, available water and phosphate content but the higher the topography, the higher the active iron content. 4. These soils are classified as Hapludalfs by Soil Taxonomy in U.S.D.A. 5. These soils must be applied with much lime, phosphate and compost to improve the soil fertility.

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Effects of Expeller Cake Fertilizer on Soil Properties and Tah Tasai Chinese Cabbage Yield in Organic Greenhouse Farm (유기농 시설하우스 토양에서 유박 시용이 토양특성 및 다채 생육에 미치는 영향)

  • Kim, Kab-Cheol;Ahn, Byung-Koo;Ko, Do-Young;Kim, Ju;Jeong, Seong-Soo
    • Korean Journal of Environmental Agriculture
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    • v.33 no.3
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    • pp.149-154
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    • 2014
  • BACKGROUND: To evaluate the application level of expeller cake fertilizer(ECF), we have investigated soil chemical properties, leaf mineral contents and yield of tah tasai Chinese cabbage in a plastic film greenhouse. METHODS AND RESULTS: Five levels of fertilizer were applied as 0%(ECF 0), 50%(ECF 50), 75%(ECF 75), 100% (ECF 100) and 150%(ECF 150) by base 1,848 kg/ha of ECF. In 2012, tah tasai Chinese cabbage was planted on April 28 in a silt loam soil and harvested on July 12. Commercial yields were measured 10 times from May 10 to July 12. Electrical conductivity (2.24~3.09 dS/m), available $P_2O_5$(484~581 mg/kg) and exchangeable cations($K^+$, $Ca^{2+}$ and $Mg^{2+}$) were tended to increase by the application of ECF. However, the range of those was not significant. The contents of T-N, K, Ca and P of tah tasai Chinese cabbage leaves were 62.2~66.5 g/kg, 44.3~48.7 g/kg, 5.1~5.9 g/kg and 5.6~6.2 g/kg, respectively. The nitrogen utilization rate of tah tasai Chinese cabbage was 39.4~51.6%, and it was decreased with increased application amount of ECF. The yield of tah tasai Chinese cabbage was 9,806 to 12,730 kg/ha on the basis of application amount of ECF and it was not increased in spite of increased ECF. CONCLUSION: The optimum dose of application of ECF for cultivation of tah tasai Chinese cabbage was ranged from 924 kg/ha(as ECF 50) to 1,386 kg/ha(as ECF 75). Environment-friendly and economical amount of applied fertilizer is more important than yield for cultivation of tah tasai Chinese cabbage.