• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.813-827
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• 2015

This study was conducted to evaluate the effect of organic inputs on soil properties in a newly reclaimed organic soils. The soil of the experiment site was very low in soil fertility and the physico-chemical properties were poor. Several organic input treatments with different source of nutrient were placed, including compost in combination with green manures for organic agricultural practices, chemical fertilizers for conventional agricultural practices, and control without fertilizer. The experiment was conducted with continuous cropping system during 3 years. The chemical properties concentration in compost+green manure treatment was increased continually compare to control and chemical fertilizer treatment, and closed to the recommended rate of fertilizer. The organic matter value for compost+green manure treatment was increased from 0.86~0.96% to 2.00~2.29% by continuous nutrient supply of compost and green manure. However, further investigation on increasing of organic matter value for 3 years is necessary to monitor carefully during the long-term because it will help to clarify the all mechanisms of organic matter on organic input application way. The available phosphate value for compost+green manure treatment was generally increased from 21.9~27.1 mg/kg to 182.0~394.1 mg/kg. In case of exchange cation, the concentration for compost+green manure treatment was increased during 2 years within the range to the recommended rate of fertilizer, however, it is expected to cause a rather over supply for 3 years.

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.3
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• pp.180-187
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• 1990

This experiment was conducted to find a methode reducing peant empty pods when it was cultivated on a newly reclaimed upland soil in Kimjae, Jeonbuk, Korea. Liming materials, slaked lime and dolomite were applied to the soil at two levels : lime requirement amount neutralizing the soil and one of 1.5 times. The results are summarized as the followings. 1. There was a yield increase of 27% from the field applied 1.5 times amount of dolomite Compared to that of slaked lime. The number of empty pods per plant was at the lowest level with the treatment of higher amount of dolomite. 2. At the maturing stage of the plant there was a positive significant correlation observed between the content of MgO and other parameters such as no, of branchs per plant dry weight per plant, no, of pods per plant and 100 seed-weight. But the correlation between MgO content and the no of empty pods was negatively significant at 5% level. 3. The content of CaO and MgO was significantly correlated to hull and pod volumes, pod surface area, hull thickness and hull weight. 4. Correlation coefficients between yield and the contents of Ca and Mg in soil at mauring stage were $0.572^{**}$ and $0.556^{**}$ respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.6
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• pp.751-759
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• 2016

It is known that the poor soil fertility of newly reclaimed saline soils is due to the lack of organic matter and available mineral nutrients for crop production. The effect of green manuring with Sesbania aculeata in combination with five rates of urea-N treatments (N0. N25, N50, N75, N100) on the productivity of a subsequent whole-crop barley and the fertility of the reclaimed saline soil in Saemangeum was evaluated in the field during 2013-2014 growing season. Sesbania was grown during summer season (June to October). The amount of Sesbania incorporated was $16.2Mg\;ha^{-1}$. Sesbania contributed to $393kg\;N\;ha^{-1}$ to the soils when ploughed down and incorporated before whole-crop barley cultivated. The performances of whole-crop barley following sesbania incorporation were significantly affected by a combination of Sesbania manuring and different N rates. The N fertilizer equivalence without N fertilizer following Sesbania was 42.6% ($63.9kg\;N\;ha^{-1}$), compared with N100 ($150kg\;N\;ha^{-1}$) in fallow soils. The whole-crop barley yield responded to N fertilizer rates in both sesbania-amended and fallow soil. The yield response to nitrogen rates in fallow soil was linear (Y=0.0586X+3.3011, $R^2=0.9534$), whereas that in sesbania-amended soils was quadratic (Y= -0.001X2+0.1322X+5.7143, $R^2=0.9576$). The yield of whole-crop barley in sesbania-amended with increasing N rates was increased up to SN75 (115 kgN) $10.3Mg\;ha^{-1}$. Apparent N recovery (ANR) of whole-crop barely showed decreased with sesbania plus increasing rates of N fertilizer. Despite higher yield with sesbania manuring plus increasing N rates, the contributions of N from Sesbania with increasing N rates to whole-crop barley were decreased, whereas those from fertilizer increment due to excessively mineralized Nitrogen. Considering yield, ANR, N contribution from Sesbania and nitrogen fertilizer, the optimum N rate was N50 rate following sesbania incorporation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.21 no.2
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• pp.277-280
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• 1976

In order to obtain the fundamental informations on the nodulation and its effect on growth of pulse crops in volcanic soil, 6 legume crops were planted in the newly reclaimed land of Cheju-do. The attached nodule weight was in the order of senna, pea, soybean (hill), white clover and kidney beans.

• Korean Journal of Soil Science and Fertilizer
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• v.11 no.4
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• pp.247-262
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• 1979

Majority of reclaimable soils in hillside lands in Korea are red yellow soils, with exception in Jeju island, where most of reclaimable hillside lands are composed of volcanic ash soils. Songjeong, Yesan and Samgag series are the major soil series of red yellow soils which are available for the reclamation. When observed in the fields, they are distinguished as reddish brown clay loam, red yellow sand loam and yellowish brown sand loam. They have moderately good physical properties but their chemical properties are generally poor for crop cultivations. The chemical properties of red yellow soils, as compared to long time cultivated (matured) soils, are characterized by very low pH, high in exchangeable Al content and phosphorus fixation capacity. Also extraodinary low available phosphorus and organic matter contents are generally observed. On the other, the chemical properties of volcanic ash soils are characterized by high armophous Fe and Al hydroxides and organic matter contents, which are the causative factors for the extremely high phosphorus fixation capacity of the soils. The phosphorus fixation capacity of volcanic acid soils are as high as 5-10 times of that of red yellow soils. Poor growth of crops on newly reclaimed red yellow soils are mainly caused by very low available P and pH and high exchangeable Al. Relatively high P fixation capacity renders the failure of effective use of applied P when the amount of application is not sufficient. Applications of lime to remove the exchangeable Al and relatively large quantity of P to lower the P fixation capacity and to increase the available P are the major recommendations for the increased crop production on red yellow hillside soils. Generally recommendable amounts of lime and P to meet the aforementioned requirements, are 200-250kg/10a of lime and $30-35kg\;P_2O_5/10a$. Over doses of lime. frequently induces the K, B, arid Zn deficiencies and lowers the uptake of P. In volcanic ash soils, it is difficult to alter the exchangeable Al and the P fixation capacity by liming and P application. This may be due to the peculiarity of volcanic ash soil in chemical properties. Because of this feature, the amelioration of volcanic ash soils is not as easy as in the case of red yellow soils. Application of P as high as $100kg\;P_2O_5/10a$ is needed to bring forth the significant yield response in barley. Combined applications of appropriate levels of P, lime, and organic matter, accompanied by deep plowing, results in around doubling of the yields of various crops on newly reclaimed red yellow soils.

• Korean Journal of Soil Science and Fertilizer
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• v.14 no.4
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• pp.190-194
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• 1982

The differences in soil productivity between the cut site and the fill site in a newly reclaimed land were compared with the experimental results conducted during 1978 to 1980 under soybean-barley and sweet potato-barley cropping systems. The results were summerized as follows; The bulk density of the cut site was near $1.5g/cm^3$ with the hardness above 23mm by Yamanaka method and that of the fill site was $1.3g/cm^3$ with the hardness of 14mm at the first year of reclaiming. The bulk densities and soil hardnesses asymptotically approched to $1.4g/cm^3$ and 19mm, respectively. The chemical productivity of the fill site was also significantly higher than that of the cut site. Differently from the bulk density and hardness, chemical compositions of the fill site maintained high untill the third year of cropping. The yields of soybean, sweet potato and barley from the cut site at the first year were very poor and, thereafter, were remarkably increased by 2 to 9 times at the third year of cropping while those from the fill site maintained high from the first year to the third year of cropping.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.2
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• pp.145-150
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• 2007

This study was conducted to evaluate the application effects of phospho-gypsum fertilizer (PGF) as reclamation material in the newly reclaimed paddy fields located in Goheung and Youngam, Jeonnam province in Korea. The PGF used in this experiment was produced by Namhae Chemical Co. as the name of Soil-Saver$^{TM}$. Prior to rice transplanting, the PGF was applied as soil amendment as the amount of $3,000kg\;ha^{-1}$. The PGF increases rice plant height and number of tiller at the heading stage by 119.9 cm and 9.1, respectively, in Youngam area. The harvest index of brown rice increased up to 5 and 13% more in the PGF applied paddy field from both sites than in the non-application of PGF at paddy field before rice transplanting, and the ripening ratio in increased in both sites to 81 and 90%. Protein content of brown rice was also greater than in the non-application of PGF at the both sites. For the effects of the reclamation by PGF in the paddy field soils, we found that PGF reduced exchangeable Na to 18 and 28% for both sites, respectively, and increased exchangeable Ca and $SO_4$. And we found relatively higher amounts of $K_2O$, CaO and MgO in the rice plants from both sites applied with PGF.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.1065-1072
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• 2010

The excavation site in the new city of inchon songdo is distributed with soft reclaimed soil and marine deposit. So, the general ground anchor is not applied to this layer of soft ground as the earth retaining support system, because of settlement. And then, Jacket pack anchor which is newly developed in order to increasing the pullout resistance by certain grout bulb formation and expansion effect in soft ground is applied to this site instead of the general ground anchor. Though the maximum horizontal displacement shows about 30mm~100mm (The maximum horizontal displacement/excavation depth$\fallingdotseq$0.32~1.0%) according to excavation sequence, generally excavation work finished stably. Also, load cell after setting shows almost increasing trend with increasing horizontal displacement. It means that the settlement of Jacket pack anchor in soft ground is good. From the result of this case, we knew that Jacket pack anchor was able to use the earth retaining support system in soft ground. Using Jacket pack anchor in soft ground, The allowance of the horizontal displacement is applied more than general value considering soil factors.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.6
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• pp.492-499
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• 2009

Effect of drip irrigation on soil salinity control and growth of vegetable crops was studied in the three reclaimed lands of Korea in 2007. Drip irrigation was done one or two times per month for reduction of salt stress by using vinyl hose with tiny holes laid on ridge surface under black plastic film mulch during growing season of cabbage and chinese cabbage. It was observed that drip irrigation was generally effective to soil salinity control, but soil salinity variation of some place was not fully solved to lower down under level of free salt stress. It is also considered that high salinity of runoff water spilled out from cultivation ridge plays another key role for soil salinity management. Consequentially, this soil salinity variation might be one of factors brought low average yield and low commercial ratio of agricultural products. Relation between soil salinity and head growth of cabbage and chinese cabbage was well expressed as logarithmic function. Surface soil EC to reach at 50% of growth reduction to the heaviest head can be estimated was $6.1dS^{\circ}{\S}m^{-1}$ for cabbage and $5.7dS\;m^{-1}$ for chinese cabbage transplanted at optimum season.

• Applied Biological Chemistry
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• v.17 no.1
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• pp.31-41
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• 1974

This study was conducted to determine the effects of soybean cultivation on yield and other characters in a newly reclaimed soil. Four factois - (1) plant density (2) compost application (3) innoculation of nodule bacteria (Rhizobium japonicum) combined with lime application (4) NPK application-were examined in a 24 factorial experiments arranged in randomized complete block design with 4 replicates. Kangio variety was used and the results obtained are summarized as follows; (1) Dense plant population, Application of Compost and application of fertilizer (NPK) gave the yields 1.7, 1.4 and 2.1 times the check respectively. The Combinations of, dense $population{\times}compost$, dense $compost{\times}fertilizer$ (NPK), $population{\times}compost{\times}fertilizer$ (NPK), and dense $population{\times}compost{\times}nodule$ bacteria with $lime{\times}fertilizer$ (NPK) increased the yields by 2.0, 3.0, 2.6 and 5.4 times than the check respectively. But little effect on yield was noted in the treatment inoculated with nodule bacteria with lime. (2) In the case of higher yield, the increased weight of 100 seeds was found. (3) A markedly increased PH was observed in all of the plots under study after the completion of experiment. (4) The compost treatment and the ferttilizer (NPK) treatment greatly increased the organic matter, total nitrogen and the available phosphorus in the soil. (5) The variation in the grain yield appeared to have a close correlation with the content of available $P_2O_5$ in the soil.