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| Titel |
The effect of peat swamp forest degradation on greenhouse gas fluxes in the
Peruvian Amazon |
| VerfasserIn |
Jeffrey van Lent, Kristell Hergoualc'h, Louis Verchot, Jan Willem van Groeningen, Oene Oenema |
| 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 |
250153801
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| Publikation (Nr.) |
 EGU/EGU2017-18822.pdf |
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| Zusammenfassung |
| Carbon-dense peat swamp forests in Peru are recurrently harvested for M. flexuosa fruits,
which is typically performed by cutting down entire palms. This research aimed to
evaluate how biogeochemical cycles are affected by this type of forest degradation.
Total soil respiration (Rs), heterotrophic respiration (Rh), CH4 and N2O fluxes,
litterfall and environmental parameters were monitored monthly for two years in an
undisturbed (UD), a moderately disturbed (MD), and a highly degraded site (HD).
The experimental setup entailed measurements in hollows and hummocks with
standing live or dead palms. Rh rates were higher in hummocks than in hollows (UD:
25.9±0.5 and 17.5±0.3, MD: 14.1±1.3 and 12.4±1.2, HD: 26.8±4.7 and 18.8±3.0 kg
C-CO2 ha−1 d−1, respectively). Unexpectedly, CH4 fluxes did not vary significantly
between hummocks and hollows, whereas N2O fluxes followed the same trend
as Rh. GHG fluxes from hummocks with a standing live or a standing dead palm
were similar. However, degradation did reduce the relative hummock area (relative
areas: 18, 10 and 4% for UD, MD, and HD, respectively). As a result, the overall
weighted average Rh in the MD site (12.4±1.6 kg C-CO2 ha−1 d−1) was lower
than the UD one (18.4±1.0 kg C-CO2 ha−1 d−1), while litter input was higher
(12.2±0.3 and 9.3±0.4 kg d.w. ha−1 d−1in the MD and UD, respectively). The HD site
exhibited Rh (17.5±1.2 kg C-CO2 ha−1 d−1) and litter input (9.4±0.2 kg d.w. ha−1
d−1) rates similar to those of the UD site. CH4 fluxes were 0.75±0.10, 0.62±0.08,
0.89±0.05 kg C-CH4 ha−1 d−1 and N2O fluxes 1.7±0.2, 1.2±0.1, 2.0±0.3 g N-N2O
ha−1 d−1 in the UD, MD and HD site, respectively. These findings suggest that
differentiating hummocks and hollows in GHG flux assessments and accounting
for changes in relative hummock areas are essential for evaluating degradation
impacts on peat C and N cycling in Amazonian peat swamp forests. These results
contribute to building knowledge on emission factors for tropical peat regions outside
of Southeast Asia and ultimately might be helpful for supporting conservation. |
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