Obermeier, W.; Lehnert, L.; Ivanov, M.; Luterbacher, J. & Bendix, J. (2018): <b>Reduced summer aboveground productivity in temperate C3 grasslands under future climate regimes</b>. <i>Earth's Future</i> <b>6</b>(5), 716-729.
Resource Description
Title:
Reduced summer aboveground productivity in temperate C3 grasslands under future climate regimes
FOR816dw ID:
316
Publication Date:
2018-05-07
License and Usage Rights:
FACE2FACE
Resource Owner(s):
Individual:
Wolfgang Obermeier
Contact:
email:
wolfgang.obermeier <at> geo.uni-marburg.de
Germany
Individual:
Lukas Lehnert
Contact:
email:
lukas.lehnert <at> staff.uni-marburg.de
Germany
Individual:
Martin Ivanov
Contact:
email:
webmaster <at> lcrs.de
Individual:
Jürg Luterbacher
Contact:
email:
webmaster <at> lcrs.de
Individual:
Jörg Bendix
Contact:
email:
bendix <at> staff.uni-marburg.de
Deutschhausstraße 12
Room No. 02 A 48
35032 Marburg
Faculty of Geography
Germany
Abstract:
Temperate grasslands play globally an important role, for example, for biodiversity conservation, livestock forage production, and carbon storage. The latter two are primarily controlled by biomass production, which is assumed to decrease with lower amounts and higher variability of precipitation, while increasing air temperature might either foster or suppress biomass production. Additionally, a higher atmospheric CO2 concentration ([CO2]) is supposed to increase biomass productivity either by directly stimulating photosynthesis or indirectly by inducing water savings (CO2 fertilization effect). Consequently, future biomass productivity is controlled by the partially contrasting effects of changing climatic conditions and [CO2], which to date are only marginally understood. This results in high uncertainties of future biomass production and carbon storage estimates. Consequently, this study aims at statistically estimating mid-21st century grassland aboveground biomass (AGB) based on 18 years of data (1998–2015) from a free air carbon enrichment experiment. We found that lower precipitation totals and a higher precipitation variability reduced AGB. Under drier conditions accompanied by increasing air temperature, AGB further decreased. Here AGB under elevated [CO2] was partly even lower compared to AGB under ambient [CO2], probably because elevated [CO2] reduced evaporative cooling of plants, increasing heat stress. This indicates a higher susceptibility of AGB to increased air temperature under future atmospheric [CO2]. Since climate models for Central Europe project increasing air temperature and decreasing total summer precipitation associated with an increasing variability, our results suggest that grassland summer AGB will be reduced in the<br/>
future, contradicting the widely expected positive yield anomalies from increasing [CO2].
Keywords:
| central Europe | biomass | climate change | climate variability | Free Air CO2 Enrichment ( FACE ) | Grassland ecology | AGB | elevated CO2 |
