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To evaluate the water quality in Juksancheon constructed wetlands for treating non-point source pollution, the removal rates of nutrients in water and the total amounts of T-N and T-P uptakes by water plants were investigated. Chemical characteristics of T-N and T-P in sediment were investigated.

This study was performed to develop extrusion pelletizer for pelletizing the compost waste food. The effect of water content on the shape of pellet, the relationship between diameter of pellet and of extrusion hole and the relationship between extrusion force and die angle were investigated. Considering the stable shape of compost pellet and the operation efficiency of pelletizer, the water content of 2~4% was considered as the best condition. And the compost pellet could not maintain it's shape at the water content of 10% or over. The strongest extrusion force was needs when the die angle had 90° in 6 mm extrusion hole diameter, on the other hand, the weakest extrusion force was need at the die angle of 45°~65°. The compression strength of pellet shows the highest strength of 9.2Mpa when we make the compost pellet after screening the compost and make it with a size of 1.18 mm(No.16) or less.

This study was conducted to investigate the application effect of liquid fertilizer using pig cadavers on potato and corn cultivations in upland field. Field experiments were designed with control (Cn), liquid fertilizer (LF), inorganic fertilizer (IF), and LF + IF treatments. Crop yields in potato and corn cultivations were higher in the order of LF + IF ≧ IF ≧ LF > Cn treatments. The potato and corn yields in LF + IF treatment were 237% and 29% greater than those in Cn treatment, respectively. Following crops harvest, soil status was improved, showing greater soil chemical properties in the LF treated areas compared to those in the Cn treatment. In addition, total CO 2 fluxes in LF + IF treatment during potato and corn cultivations were significantly increased compared with Cn and IF treatments. Therefore, these results suggest that LF application was effective on crop cultivation and improvement of soil fertility.