Chemistry of Soil Organic Matter

土壤有機質化學

Michael H. B. Hayes ； 曾聰堯(Tsung-Yao Tseng) ； 王明光(Ming-Kuang Wang)

《台灣林業科學》 22卷3期 (2007/09) Pp. 215-226

https://doi.org/10.7075/TJFS.200709.0215

摘要

土壤及水體中均存有有機物質，而腐植物質(humic substances, HSs)顯然是自然界有機化合物中含量最豐富的物質。有機碳(organic carbon, OC)在土壤有機質(soil organic matter, SOM)中的含量被廣泛接受的數值大約是(14~15)×10^17 g，若以有機碳含量15×10^17 g為基值，則由土壤有機質(SOM)所估計之量約為由陸棲生物量(biomass)所估計之量（大約5.6×10^17g）的2.5~3倍。然而在降雨量充足的森林及草生地土壤中，有機碳的蓄存量則更多。長期而言，從動、植物殘骸而生成的淨初級生產量(net primary production, NPP)的輸入，到生物轉化作用（土壤呼吸）的損失（輸出），有機碳的蓄存量（估算）大約在68×10^15g y^(-1)，呈現穩定狀態。
近年來，土壤有機質(SOM)與碳吸存（蓄存）、溫室暖化及溫室效應的關係再次被認同。土壤經營管理在碳排放及吸存上扮演重要角色，因此土壤經營管理在全球暖化議題上是一個重要的項目。
因為腐植物質在土壤及水體環境中豐富含量及其扮演的角色，因此科學上探索腐植物質之組成與結構有其重要性。在實際而長期的考量下，這些研究是基於了解腐植物質在環境中的腐植化機制及其多變的角色。

關鍵字

碳吸存 ； 全球暖化 ； 腐植物質 ； 土壤有機質

並列摘要

Humic substances (HSs) are by far the most abundant of the organic components of nature, and are present in all soils and natural waters that contain organic matter. The more widely accepted values for organic carbon (OC) in soil organic matter (SOM) are in the range of (14~15)×10^17g. On the basis of a value of 15×10^17g, then the pool of OC in SOM is (2.5~3.0)-times greater than that of the terrestrial biomass estimated to be ca 5.6×10^17g. However, in forest and grassland soils with adequate rainfall, the reserves are very much greater. In broad terms, the pool represents a steady state between the input of plant and animal debris from net primary production (NPP) and losses from biological transformations (soil respiration) of the order of 68×10^15g y^(-1).
The importance of the SOM to carbon sequestration and global warming, or the greenhouse effect, has recently been recognised. Soil management is important in relation to the role of soils as sources and sinks of C, and hence it is important in terms of global warming issues.
Because of the abundances and roles of HSs in soil and aquatic environments, studies of their compositions and structures can be justified on the basis of scientific curiosity. In terms of practical considerations, such studies are fundamental to an understanding of the mechanisms of the multifarious roles that HSs have in the environment.

並列關鍵字

carbon sequestration ； global warming ； humic substances ； soil organic matter