Please use this identifier to cite or link to this item:
http://hdl.handle.net/2067/30824
Title: | Biotic degradation at night, abiotic degradation at day: positive feedbacks on litter decomposition in drylands | Authors: | Gliksman, D. Grunzweig Jm Rey, A. Seligmann, R. Dumbur, R. Sperling, O. Navon, Y. Haenel, S. De Angelis, Paolo Arnone Ja |
Journal: | GLOBAL CHANGE BIOLOGY | Issue Date: | 2017 | Abstract: | The arid and semi-arid drylands of the world are increasingly recognized for their role in the terrestrial net carbon dioxide (CO2) uptake, which depends largely on plant litter decomposition and the subsequent release of CO2 back to the atmosphere. Observed decomposition rates in drylands are higher than predictions by biogeochemical models, which are traditionally based on microbial (biotic) degradation enabled by precipitation as the main mechanism of litter decomposition. Consequently, recent research in drylands has focused on abiotic mechanisms, mainly photochemical and thermal degradation, but they only partly explain litter decomposition under dry conditions, suggesting the operation of an additional mechanism. Here we show that in the absence of precipitation, absorption of dew and water vapor by litter in the field enables microbial degradation at night. By experimentally manipulating solar irradiance and nighttime air humidity, we estimated that most of the litter CO2 efflux and decay occurring in the dry season was due to nighttime microbial degradation, with considerable additional contributions from photochemical and thermal degradation during the daytime. In a complementary study, at three sites across the Mediterranean Basin, litter CO2 efflux was largely explained by litter moisture driving microbial degradation and ultraviolet radiation driving photodegradation. We further observed mutual enhancement of microbial activity and photodegradation at a daily scale. Identifying the interplay of decay mechanisms enhances our understanding of carbon turnover in drylands, which should improve the predictions of the long-term trend of global carbon sequestration. |
URI: | http://hdl.handle.net/2067/30824 | ISSN: | 13541013 | DOI: | 10.1111/gcb.13465 |
Appears in Collections: | A1. Articolo in rivista |
Files in This Item:
File | Size | Format | |
---|---|---|---|
2017_GCB_Gliksman_et_al_DSPACE.pdf | 405.56 kB | Adobe PDF | View/Open |
SCOPUSTM
Citations
5
80
Last Week
0
0
Last month
1
1
checked on Mar 24, 2024
Page view(s)
73
Last Week
0
0
Last month
0
0
checked on Mar 27, 2024
Download(s)
41
checked on Mar 27, 2024
Google ScholarTM
Check
Altmetric
All documents in the "Unitus Open Access" community are published as open access.
All documents in the community "Prodotti della Ricerca" are restricted access unless otherwise indicated for specific documents