• 作者： 莊作權
• 作者服務機構： 國立中興大學土壤研究所
• 中文摘要： 本研究供試實驗之土壤共採用臺灣西部七大土類之十二種農地土壤，抽取出粘粒，將其中之碳酸鹽類、有機質、游離氧化鐵均去除。本研究之目的即在探討溫度處理及乾濕效應在土壤銨固定土之影響。 經由0，10 ，10 ，1.0 M等不同銨離子濃度平衡結果，以枯板岩新沖積土及臺灣粘土的固定性銨為最高，而以大埔美紅壤為最低。土壤中原有的固定態銨含量從最低之大埔美紅壤(1.73 cmol/kg soil)至最高的枯板岩新沖積土(5.59 cmol/kg soil)。交換性銨與固定性銨之比值隨外加銨濃度之增加而提高，提高之程度則受土壤CEC和粘粒含量等所影響，故土壤對銨固定量與粘粒含量及膨脹性粘土礦物含量有密切關係。 用25℃，40℃，70℃等三種溫度處理結果，發現其對土壤及粘粒之固定性銨影響甚小，但加溫至110℃時固定銨之量顯著增加，其中以大埔美紅壤增加12.9%至岸內砂頁岩新沖積土增加98.7%，此顯示加溫至110℃可移去粘土礦物間層水分，使粘粒對銨的固定量增加。 考慮經1M (方程式無法摘錄) 處理後之固定性銨扣除原有固定性銨後，發現以砂頁岩沖積土及臺灣粘土所增加的固定性銨較多，此二土類所含的膨脹性粘土礦物含量亦較多。
• 英文摘要： Twelve soil samples representing seven soil groups of cultivated land of western Taiwan were collect-ed and used in this study. The clay fraction was separated and O.M.,free iron oxides and carbonates wereremoved. The objective of this study was to investigate the effects of temperature and drying-wettingtreatments on ammonium fixation in soils. Equilibrated with ammonium solution of different concentrations,e.g., 0, 10 , 10 ,l.0M, thehighest amount of flxed ammonium was found in Recent Slate Alluvial soils and Taiwan Clays, and thelowest in Latosol of Ta-Pu-Mei. The native fixed ammonium in soils ranged from 1.73 cmol kg soil inLatosols to 5.59 cmol kg soil in Recents, ate Alluvial Soils. The ratio of Exch.-NH to fixed-NH in soi1and clay increased with increasing NH concentrations. The extent of the increase in fixed-NH in soilvaried with soil CEC and clay content. The fixed ammonium in soil highly correlated with the clay contentand the amount of expanding clay minerals. Treatment with temperature at 25℃, 40℃ and 70℃ had little influence on the fixed ammoniumin both the soil and clay. With heating to 110℃, the fixed ammonium in the clay increased significantly.There was a 12.9％ increase in Latosol of Ta-Pu-Mei, and up to a 98.7％ increase in Recent Sandstone-Shale Alluvial Soil of An-Nei. This indicates that increasing temperature to 110℃ may remove more watermolecules flom the interlayer of the clay minerals, thus increasing the amount of fixed arnmonium in theclay fraction. In considering deduction of native fixed ammonium from apparent fixed ammoniurn（after treatedwith 1M NH Cl solution）, the net increase in fixed ammonium was found to be higher in Sandstone-ShaleAlluvial soils and Taiwan Clay. The higher amount of expanding clay minerals also was found in these twogroups of soil.
• 中文關鍵字： ammonium fixation; dry-wetting effect; clay minerals
• 英文關鍵字： --