Warming has a larger and more persistent effect than elevated CO2 on growing season soil nitrogen availability in a species-rich grassland
| Autor: | Paul C. D. Newton, Yui Osanai, Mark J. Hovenden |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
0106 biological sciences
Soil Science chemistry.chemical_element Growing season Plant Science complex mixtures 01 natural sciences Grassland chemistry.chemical_compound Nitrate 2. Zero hunger geography geography.geographical_feature_category Ecology Global warming Biosphere Biogeochemistry Carbon sink 04 agricultural and veterinary sciences 15. Life on land Nitrogen chemistry Agronomy 13. Climate action 040103 agronomy & agriculture 0401 agriculture forestry and fisheries Environmental science 010606 plant biology & botany |
| Zdroj: | Plant and Soil. 421:417-428 |
| ISSN: | 1573-5036 0032-079X |
| DOI: | 10.1007/s11104-017-3474-8 |
| Popis: | The terrestrial biosphere’s ability to capture carbon is dependent upon soil nitrogen (N) availability, which might reduce as CO2 increases, but global warming has the potential to offset CO2 effects. Here we examine the interactive impact of elevated CO2 (eCO2) and warming on soil N availability and transformations in a low-fertility native grassland in Tasmania, Australia. Using ion exchange membranes, we examined soil nitrogen availability during the growing season from 2004 to 2010 in the TasFACE experiment. We also estimated soil N transformation rates using laboratory incubations. Soil N availability varied strongly over time but was more than doubled by experimental warming of 2°C, an impact that was consistent from the fifth year of the experiment to its conclusion. Elevated CO2 reduced soil N availability by ~28%, although this varied strongly over time. Treatment effects on potential N mineralisation also varied strongly from year to year but tended to be reduced by eCO2 and increased by warming. These results suggest that warming should increase soil N availability more strongly than it is suppressed by eCO2 in low fertility grasslands such as this, stimulating terrestrial carbon sinks by preventing eCO2-induced nitrogen limitation of primary productivity. |
| Databáze: | OpenAIRE |
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