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| Titel |
Variations of soil organic C following land use change on deep-loess
hillsopes in China |
| VerfasserIn |
Xiaodong Gao, Xining Zhao, Tingting Meng |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250140126
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| Publikation (Nr.) |
 EGU/EGU2017-3474.pdf |
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| Zusammenfassung |
| Land use change is a key factor driving changes in soil organic C (SOC) around the world.
However, the changes in SOC following land use changes have not been fully elucidated,
especially for deep soils (> 100 cm). Thus, we investigated the variations of SOC under
different land uses on hillslopes of the Loess Plateau in China based on datasets in the 0-100
cm. And we quantified the contribution of deep-layer SOC (200-1800 cm) to that of whole
soil profiles (0-1800 cm). The results showed that in shallow profiles (0-100 cm) land uses
significantly (P<0.05) influenced the distribution of SOC contents and stocks in
surface layer (0-20 cm) but not subsurface layers (20-100 cm). Pearson correlation
analysis indicated that soil texture fractions and total N were significantly (P<0.05 or
0.01) correlated with SOC content, which may have masked effects of land use
change on SOC. In deep profiles (0-1800 cm), SOC stock generally decreased with
soil depth; the mean SOC stock, as a proportion of the amount in the 0-100 cm,
declined from 87.6% in the 200-300 cm to 32.7% in the 1700-1800 cm. But deep soils
showed high SOC sequestration capacity. The SOC accumulated in the 100-1800 m
equaled 90.6, 91.6, 87.5, and 88.6% of amounts in the top 100 cm under cropland,
7-yr-old grassland, 30-yr-old grassland, and jujube orchard, respectively. The results
provide insights into SOC dynamics following land use changes and stressed the
importance of deep-layer SOC in estimating total SOC inventory in deep loess soils. |
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