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| Titel |
Phosphorus addition can trigger strong priming of soil organic matter decomposition |
| VerfasserIn |
Na Qiao, Doug Schaefer, Xiaoming Zou |
| Konferenz |
EGU General Assembly 2015
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250114727
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| Publikation (Nr.) |
 EGU/EGU2015-15540.pdf |
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| Zusammenfassung |
| Atmospheric dust and nitrogen deposition may alter phosphorus (P) availability in soils.
Understanding how P affects decomposition of soil organic matter (OM) is important to
unravel relationships between P and carbon (C) cycles. To examine P priming effect on
decomposition of OM, we added P at three levels on a basis of organic C content (0.0156%,
0.0625% and 0.25% of organic-C contents) to four types of OM (leaf litter, wood
litter, organic and mineral soils collected from a subtropical forest) in a microcosm
experiment over a 3-day period. We detected P priming effect on decomposition of
all four types of OM and the magnitude of this priming effect varied with both
OM types and P addition levels. Efflux of CO2 from decomposing leaf litter was
decreased by 18.4% with the low-level P addition but increased by 11.9% in the
intermediate-level P addition treatments. High-level P addition did not change CO2 efflux
from decomposing leaf-litter. For the wood OM, the low-level P addition reduced
CO2 efflux by 10.2%, intermediate-level P addition had no effect, but high-level P
addition increased CO2 efflux by 17.0%. Positive P priming effect on CO2 efflux
occurred in both organic and mineral soils at all three-level P additions and the
magnitude of this priming effect increased with P addition levels. The high-level P
addition treatment increased CO2 effluxes by 66.3% in the organic soil and by
25.4% in the mineral soil. We conclude that increase in P availability may trigger
strong priming effect on CO2 efflux in forest soils, consequently produce C-climate
feedbacks.
Keywords: Priming effect, available phosphorus, plant litter, soil organic matter |
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