| Summary: | 碩士 === 國立臺灣大學 === 環境工程學研究所 === 102 === The speciations of copper and zinc, repectively, in poultry manure and soils from Yi-lan River basin have been investigated in order to establish a model to predict the movement of these two metals and to estimate the allowable rate of application of manure to farmlands. The total concentration of copper in tableland(LTt) and in riverbed(LTr) are 139.4 mg/kg and 154.9 mg/kg, respectively, which are higher than the concentration of copper in manure, 99.7 mg/kg. This observation indicates that there is accumulation of metals in the farmland soils due to the application of manure. Fifty three percent of copper and 49% of zinc in manure are associated with organic matter. Thirty five percent (35%) of total copper in riverbed soils and 39.9% of total copper in tableland soils are associated with organic matter, while most of zinc are in the form of oxide in soils. There are dynamic changes among different forms of metals in laboratory-scale soil columns with different treatment of manure.Copper and zinc were transformed from the organic form in amended manure to the exchangeable, organic or oxide-bound forms in soils, or removed from soil by infiltrating rainfall or irrigation waters. The rate of the decomposition of organic matter was strongly influence the movement of metals. By using a calibrated mathematical model, the amount of manure allowed to apply on the field was estimatedto be 1.35 kg/m2 per year, which is much less than the current application rate, 14 kg/m2 per year.
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