Abstract
Models predict that global warming may increase aridity in water-limited ecosystems by accelerating evapotranspiration. We show that interactions between warming and the dominant biota in a grassland ecosystem produced the reverse effect. In a 2-year field experiment, simulated warming increased spring soil moisture by 5-10% under both ambient and elevated CO2. Warming also accelerated the decline of canopy greenness (normalized difference vegetation index) each spring by 11-17% by inducing earlier plant senescence. Lower transpirational water losses resulting from this earlier senescence provide a mechanism for the unexpected rise in soil moisture. Our findings illustrate the potential for organism-environment interactions to modify the direction as well as the magnitude of global change effects on ecosystem functioning.
Original language | English (US) |
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Pages (from-to) | 9892-9893 |
Number of pages | 2 |
Journal | Proceedings of the National Academy of Sciences of the United States of America |
Volume | 100 |
Issue number | 17 |
DOIs | |
State | Published - Aug 19 2003 |
ASJC Scopus subject areas
- General