土壤銨離子潛在緩衝能力與固定態銨釋放速率之研究

Study on Potential Buffering Capacity of Soil Ammonium and Release Rate of Fixed Ammonium

吳宇鑫(Yu-Hsin Wu) ； 陳鴻基(Horng-Ji Chen) ； 曾志明(Jyh-Myng Zen)

《中華農學會報》 8卷1期 (2007/02) Pp. 83-104

https://doi.org/10.6730/JAAC.200702_8(1).0006

摘要

氮是作物生長所需的首要元素，在土壤氮循環中土壤對銨離子的固定與釋放，掌控著氮養分的供應與防止氮淋洗流失的重要角色，間接也可減少因硝酸根與亞硝酸根離子對土壤環境及地下水所造成的污染問題。本試驗選用三種不同土類土壤，利用銨離子的吸附與脫附試驗由銨離子總量／強度圖求取銨離子吸附與脫附潛在緩衝能力，就不同土壤成分與性質比較施用堆肥處理對銨離子潛在緩衝能力與脫附速率上的影響。試驗結果指出三種土類土壤在未處理下對銨離子之潛在緩衝能力大小認大里系＞秀水系＞吳厝系。吳厝系土壤在堆肥處理後銨離子之潛在緩衝能力明顯提高。在脫附潛勢方面，吳厝系士壤在堆肥施用後其脫附潛勢明顯大於未處理。銨離子的吸附潛在緩衡能力與脫附潛在緩衝能力之間有明顯的相關關係存在(r^2=0.942(上標 **))。三種土系在固定態銨總釋放量上的大小順序與脫附潛在緩衝能力的大小顯序有相同的趨勢，顯示由銨離子脫附潛在緩衝能力可預估固定態銨總釋放量。由將固定態銨釋放量與時間代入各種釋放動力論模式的結果，顯示Elovich方程式最適合描述三種土類土壤表底土有無堆肥處理土壤固定態銨的釋放動力論，未來可以此作為評估土壤固定態銨之釋放量與適時適量供應氮以供作物吸收的參考。

關鍵字

固定態銨 ； 潛勢緩衝量 ； 釋放動力論

並列摘要

Nitrogen is the primary element for growing crops; both ammonium fixation and release of soil nitrogen play an important role in supplying nitrogen nutrient and preventing nitrogen loss that indirectly decrease pollution of NO2(superscript -) and NO3(superscript -) in soil environment and ground water. Adsorptive and desorptive potential buffering capacity from quantity/intensity diagrams and release rate of ammonium in three different soil groups are presented in this study. The results have indicated that the order of potential buffering capacity for ammonium in three soils with blank of compost treatment was Tali Series ＞ Shiushui Series＞ Wutso Series. Compost treatment, on the other hand, can largely increase the potential buffering capacity of ammonium in Wutso Series. The desorptive potential buffering capacity of ammonium in compost treatment was more than that of blank treatment for Wutso Series. The relationship between adsorptive and desorptive potential buffering capacity of ammonium was obvious (r^2=0.942(superscript **)). The order of release amounts of fixed ammonium for three soil series showed the same order as those of desorptive potential buffering capacity, which indicated that the release amounts of fixed ammonium could be estimated by desorptive potential buffering capacity of ammonium. Among various released kinetic models for release amounts of fixed ammonium and time, Elovich equation showed the most appropriate description for release kinetics of fixed ammonium in three soils with blank and compost treatment. Most important of all, the model could be used to estimate the release amounts of fixed ammonium and as a reference of applying appropriate nitrogen for growing crops in the future.

並列關鍵字

Fixed ammonium ； Potential buffering capacity ； Release kinetics