臺灣博碩士論文加值系統

腐植質於土壤中為不定形及非均質性的有機化合物，係由於微生物新陳代謝死亡的細胞資材的產物，基於以上發現到目前為止，顯示有多種對植物新陳代謝的影響，可依它們的來源、分子量大小、化學特性和濃度而定。然而在自然環境中不斷有許多的路徑造成土壤中有機物質的累積，故本研究欲探討土壤中穩定的有機物直接與新鮮的有機資材接觸所產生之變化，是否可由此生成存於土壤中穩定的有機物質。因此本研究以腐植酸(humic acid)分別與醣類葡萄糖(glucose)與玉米澱粉(corn starch)進行反應，並研究反應產物以了解有機物的變化的特性。主要的分析方法為元素分析(EA)、傅立葉散反射紅外光譜(FTIR-DRIFT)與衰減式全反射紅外光譜分析(FTIR-ATR)、固態核磁共振光譜分析(13C-NMR)以及二氧化碳釋放速率之穩定性分析。由EA可知腐植酸含有高量的羧酸基(-COOH)，而FTIR與13C-NMR光譜顯示反應產物的架構變化很明顯，腐植酸與醣類反應之後，醣類會受到腐植酸之羧酸基團的修飾，可使反應產物成為穩定的有機物質。依據13C-NMR光譜分析結果，計算可得腐植酸的芳香度為56.2%，腐植酸與澱粉反應產物之芳香度可達53.4%。反應產物的二氧化碳釋放速率(42.09-44.20 mg g-1 d-1)均低於澱粉(47.25 mg g-1 d-1)，顯示與腐植酸與澱粉反應後的產物，確實有趨於穩定的性質。本研究結果顯示腐植酸與新鮮的有機物質直接接觸時，可藉由本身之特性官能基修飾，並且使得有機物質穩定化，此種反應將有助增加土壤中的有機碳含量的累積。

The humic substance (HS) is heterogeneous organic compounds formed in the soil as by-products of microbial metabolism on dead cell materials, were found up to now to exhibit a range of different effects on plant metabolism. It is depending on their organic, molecular size, chemical characteristics and concentration. However, there are many ways by which organic matter can be accumulated in natural soil environment. The objective of this research is to investigate the stable organic matter in the soil, which is change in direct contact with the fresh organic matter, whether stable of organic matter was formed. For this reason, through the reaction of humic acid (HA) and carbohydrate (corn starch and glucose), and reaction products were studied in order to characterize the variation of organic matter. The main analytical methods were elemental analyzer (EA), Fourier transform infrared spectroscopy (FTIR) connected with diffuse reflectance Fourier transform infared (DRIFT) and attenuated total reflectance (ATR), respectively; and solid state 13C nuclear magnetic resonance spectroscopy (13C-NMR), and stability analysis of the release speed of carbon dioxide. The EA demonstrated that HA contain a high amount of carboxyl (-COOH), as well FTIR and 13C-NMR spectra of reaction products were indicated that a high rate of change in structure. The reaction products were modified by carboxyl from HA which was become stable organic matter. Accordingly to the integration of quantitative analysis of 13C-NMR spectra, the value of aromaticity of HA was 56.2%, and the reaction products were reached 53.4%. The stability analysis part of the carbon dioxide release speed, the reaction products were (42.09-44.20 mg g-1 day) lower than corn starch (47.25 mg g-1 day) that show in tending become to stable matter. In conclusion, carbohydrate could be modified by function groups of HA, and which can increase the organic carbon accumulation in the soil.

中文摘要 IV
英文摘要 V
目錄 VI
表次 VII
圖次 VIII
壹、前言 1
貳、文獻回顧 3
一、土壤有機質之分類與效應 3
二、腐植質概述 4
三、泥炭土之形成 11
四、醣類之概述 12
參、材料與方法 13
一、研究架構 13
二、研究之材料及方法 14
三、腐植酸與醣類反應及其產物之特性分析方法 20
肆、結果與討論 25
一、泥炭土基本性質分析 25
二、腐植酸萃取量 25
三、腐植酸與醣類反應條件測試 25
四、腐植酸與醣類之反應分析結果 27
伍、結論 60
陸、參考文獻 61

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