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| Titel |
Soil organic carbon accumulation in afforested/abandoned arable fields in Taiwan |
| VerfasserIn |
Yi-Han Lin, Chih-Hsin Cheng, Yu-Hsuan Huang |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250121954
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| Publikation (Nr.) |
 EGU/EGU2016-863.pdf |
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| Zusammenfassung |
| Afforestation or abandonment of arable fields has been proposed as a way to increase
terrestrial carbon storage and mitigate anthropogenic carbon emissions. When the arable
fields are afforested or abandoned, the accumulation in soil organic carbon (SOC) is a key
pool to sequestrate carbon. However, high uncertainties still exist in the tropics and subtropics
because of fast SOC turnover rates and variable land use managements in these areas. In this
study, a total of eleven sites with afforested/abandoned age over 15 years and elevation
ranging from 16 to 2,056 m were investigated. We examined the increments of SOC by
comparing with the adjacent tilled (e.g. croplands) and non-tilled (e.g. tea plantation or
orchards) fields in two sampling layers, 0 - 10 and 10 - 20 cm in depth. In addition, density
fractionation of SOC was also conducted in order to differentiate SOC into light fraction,
intra-aggregate fraction, and heavy fraction to gain more information about the
mechanism of SOC sequestration. Our results indicated that the increments of SOC
concentration and stock varied with elevation, land use management, and soil depth.
For the sites with elevation below 500 m, the SOC concentration and stock in the
abandoned fields were 14.3 ± 0.9 mg C g−1 and 14.6 ± 4.6 Mg C ha−1 higher
than the adjacent tilled fields, and 10.2 ± 6.3 mg C g−1and 6.4 ± 6.2 Mg C ha−1
higher than the adjacent non-tilled fields for surface 0-10 cm. For the sites with
elevation above 500 m, the SOC concentration in the abandoned arable fields were 22.8
± 12.8 mg C g−1 higher than the adjacent tilled fields, but the SOC stock might
not be different due to high stone content in abandoned field. Moreover, the SOC
concentration and stock in abandoned field were not different or even less than non-tilled
fields where organic amendments were frequently applied. The increments of SOC
for 10-20 cm soils were less evident than those for surface 0-10 cm soils, and the
differences were only observed in the SOC concentration in some sites. The preliminary
results from SOC fractions further indicated that the increment of SOC in the low
elevation afforested/abandoned fields were from all three fractions, but only one
or two fractions (e.g. light fraction or intra-aggregate) increments were observed
in the high elevation (> 500 m) afforested/abandoned field. More studies about
SOC fraction are still underway and will present in the General Assembly 2016. |
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