利用普魯士藍修飾電極法探討土壤固定態銨的釋放速率

Study on Release Rate of Soil Fixed Ammonium Using an Electrochemical Method with Prussian Blue-Modified Electrode

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. 1-20

https://doi.org/10.6730/JAAC.200702_8(1).0001

摘要

氮能以固定態銨離子的方式儲存在土壤中，以供作物生長時持續性地吸收與利用。同時，銨離子的固定與釋放間接也會影響到硝酸根及亞硝酸根對土壤環境及地下水的污染問題。利用普魯士藍修飾網版印刷碳電極搭配流動注入系統對銨離子有很好的偵測效果。以電化學方法可進行土壤化學研究領域中的固定態銨釋放及釋放動力論之研究，試驗結果顯示，三種土壤表底土在有無堆肥處理中的固定態銨釋放量均以秀水系為最大，在釋放速率上秀水系也大於大里系和吳厝系，本研究提出一種所謂類固定的說法，即來自雲母類和綠泥石類混層礦物對銨離子的固定，此種固定態銨較容易釋出。經由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方程式最適合描述釋放動力論，以此釋放模式的評估應可作為不同土類土壤適時適量施用氮肥上的參考與依據，以避免過量氮肥施用所造成的浪費及環境污染問題。

關鍵字

普魯士藍修飾電極 ； 固定態銨 ； 釋放動力論

並列摘要

Nitrogen can be reserved as fixed ammonium for sustaining uptake and use of crop. Fixation and release of ammonium can indirectly affect the pollution of NO2(superscript -) and NO3(superscript -) in soil environment and ground water. Soil ammonium can be detected using a Prussian blue-modified screen printed carbon electrode coupled with flow injection analysis. The released kinetics of fixed ammonium can thus be studied by electrochemical method. The experimental results indicated Shiushui Series released the largest amount with the highest results rate of fixed ammonium in surface sod and subsoil among the three soils of Shiusbui, Tali, and Wutso Series. The soil ammonium was fixed by interlayer of mixed layer from mica and chlorite, which were easily being released to solution, Elovich equation provides the best description for released kinetics of fixed ammonium among various kinetic equations. The evaluation of released kinetic model could be taken as reference and be used as the basis of applying nitrogen fertilizer in suitable time and amount for various soil groups. This could avoid both the waste and environmental pollution caused by overuse of nitrogen fertilized.

並列關鍵字

Prussian blue-modified electrode ； Fixed ammonium ； Released kinetics