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Titel |
Responses of soil respiration and its temperature/moisture sensitivity to precipitation in three subtropical forests in southern China |
VerfasserIn |
H. Jiang, Q. Deng, G. Zhou, D. Hui, D. Zhang, S. Liu, G. Chu, J. Li |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1726-4170
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Digitales Dokument |
URL |
Erschienen |
In: Biogeosciences ; 10, no. 6 ; Nr. 10, no. 6 (2013-06-18), S.3963-3982 |
Datensatznummer |
250018295
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Publikation (Nr.) |
copernicus.org/bg-10-3963-2013.pdf |
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Zusammenfassung |
Both long-term observation data and model simulations suggest an increasing
chance of serious drought in the dry season and extreme flood in the wet
season in southern China, yet little is known about how changes in
precipitation pattern will affect soil respiration in the region. We
conducted a field experiment to study the responses of soil respiration to
precipitation manipulations – precipitation exclusion to mimic drought,
double precipitation to simulate flood, and ambient precipitation as control
(abbr. EP, DP and AP, respectively) – in three subtropical forests in
southern China. The three forest sites include Masson pine forest (PF), coniferous
and broad-leaved mixed forest (MF) and monsoon evergreen broad-leaved forest
(BF). Our observations showed that altered precipitation strongly influenced
soil respiration, not only through the well-known direct effects of soil
moisture on plant and microbial activities, but also by modification of both
moisture and temperature sensitivity of soil respiration. In the dry season,
soil respiration and its temperature sensitivity, as well as fine root and
soil microbial biomass, showed rising trends with precipitation increases in
the three forest sites. Contrarily, the moisture sensitivity of soil
respiration decreased with precipitation increases. In the wet season,
different treatments showed different effects in three forest sites. The EP
treatment decreased fine root biomass, soil microbial biomass, soil
respiration and its temperature sensitivity, but enhanced soil moisture
sensitivity in all three forest sites. The DP treatment significantly
increased soil respiration, fine root and soil microbial biomass in the PF
only, and no significant change was found for the soil temperature
sensitivity. However, the DP treatment in the MF and BF reduced soil
temperature sensitivity significantly in the wet season. Our results
indicated that soil respiration would decrease in the three subtropical
forests if soil moisture continues to decrease in the future. More rainfall
in the wet season could have limited effect on the response of soil
respiration to the rising of temperature in the BF and MF. |
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