Summary: | 碩士 === 國立屏東科技大學 === 環境工程與科學系所 === 97 === The carbon stock of an independent ecosystem is able to reflect the carbon storage capability of such ecosystem, but this also depends on the accurate estimation of carbon stock in order to serve as a reliable baseline. This study collected a total of 544 cultivated and forest soil pedons in nine soil orders (Inceptisols, Entisols, Vertisols, Mollisols, Spodosols, Andisols, Alfisols, Ultisols and Oxisols) at different regions in Taiwan to estimate their organic carbon stock within the depth of 0-30 cm, 0-50 cm and 0-100 cm. Meanwhile, it has also probed into the effects on soil natures, soil types and vegetation types toward soil organic carbon stock; and explored the soil organic carbon stock of Taiwan in comparison to that in other countries to serve as a reference in the issues of soil management and global warming.
The experimental results indicate that the respective pH, Bd and organic carbon contents of four soil orders of Inceptisols, Entrosols, Ultisols and Alfisols have shown a significantly (p<0.05) negative correlation, while clay and organic carbon contents have shown a negative correlation, and only Ultisols has shown a significant confidence at p<0.001. The soil organic stock range of different soil orders (nine kinds of soil orders) of within 1 m below the topsoil is 8.86 -36.62 kg/m2, and among them, the highest range goes to Spodosols, and the lowest, Oxisols. A high coefficient of variation of organic carbon stock of topsoil at different depths below 0-30 cm, 0-50 cm and 0-100 cm demonstrates a large spatial variation of site conditions of soil organic carbon stock. The 0-30 cm soil depth accounts for 55% average value of total organic carbon rate found within 1m of topsoil; and that 0-50 cm soil depth accounts for an average value of 73%. This shows that most of Taiwan’s soil organic carbon is stored within 0-50 cm soil depth. Among them, the rate of organic carbon stored within 0-30 cm soil depth is even higher, and that the organic carbon stock of all soil orders increase significantly following an accumulation of soil depth. In Taiwan, the total soil organic carbon stocks pool of within 1 m soil depth is approximately 396 Tg, and among them, 172 Tg is found in cultivated soils and 224 Tg in forest soils. The total soil organic carbon stocks pool of within 1 m of Taiwan’s topsoil is only higher than Hong Kong, and lower than the Brazilian River Basin and Ohio in the United States.
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