Contrasting response of grassland versus forest carbon and water fluxes to spring drought in Switzerland

Since the European summer heat wave of 2003, considerable attention has been paid to the impacts of exceptional weather events on terrestrial ecosystems. While our understanding of the effects of summer drought on ecosystem carbon and water vapour fluxes has recently advanced, the effects of spring drought remain unclear. In Switzerland, spring 2011 (March–May) was the warmest and among the driest since the beginning of meteorological measurements. This study synthesizes Swiss FluxNet data from three grassland and two forest ecosystems to investigate the effects of this spring drought. Across all sites, spring phenological development was 11 days earlier in 2011 compared to the mean of 2000–2011. Soil moisture related reductions of gross primary productivity (GPP) were found at the lowland grassland sites, where productivity did not recover following grass cuts. In contrast, spring GPP was enhanced at the montane grassland and both forests (mixed deciduous and evergreen). Evapotranspiration (ET) was reduced in forests, which also substantially increased their water-use efficiency (WUE) during spring drought, but not in grasslands. These contrasting responses to spring drought of grasslands compared to forests reflect different adaptive strategies between vegetation types, highly relevant to biosphere–atmosphere feedbacks in the climate system.

[1]  M. S. Moran,et al.  Ecosystem resilience despite large-scale altered hydroclimatic conditions , 2013, Nature.

[2]  Huadong Guo,et al.  The 2010 spring drought reduced primary productivity in southwestern China , 2012 .

[3]  J. Vogt,et al.  Development of a Combined Drought Indicator to detect agricultural drought in Europe , 2012 .

[4]  Pascal Yiou,et al.  Asymmetric European summer heat predictability from wet and dry southern winters and springs , 2012 .

[5]  A. Ditta.  How helpful is nanotechnology in agriculture? , 2012 .

[6]  Stephen J. Del Grosso,et al.  Impact of precipitation dynamics on net ecosystem productivity , 2012 .

[7]  Nathaniel A. Brunsell,et al.  Timing of climate variability and grassland productivity , 2012, Proceedings of the National Academy of Sciences.

[8]  Nina Buchmann,et al.  The Carbon Balance of Two Contrasting Mountain Forest Ecosystems in Switzerland: Similar Annual Trends, but Seasonal Differences , 2011, Ecosystems.

[9]  Benjamin L Turner,et al.  Carbon sequestration potential of tropical pasture compared with afforestation in Panama , 2011 .

[10]  Steven D. Chandler.  Radioactive waste policy and legislation: 50 years on from the 1960 Act , 2011, Journal of radiological protection : official journal of the Society for Radiological Protection.

[11]  Ricardo García-Herrera,et al.  The Hot Summer of 2010: Redrawing the Temperature Record Map of Europe , 2011, Science.

[12]  N. Q. Dinh,et al.  Summer drought influence on CO2 and water fluxes of extensively managed grassland in Germany , 2011 .

[13]  G. Sun,et al.  Effects of spring drought on carbon sequestration, evapotranspiration and water use efficiency in the songnen meadow steppe in northeast China , 2011 .

[14]  Jürg Fuhrer,et al.  Swiss Climate Change Scenarios CH2011 , 2011 .

[15]  Y. L. Li,et al.  Summer drought influence on CO2 and water fluxes of extensively managed grassland in Germany , 2011 .

[16]  P. Ciais,et al.  Influence of spring and autumn phenological transitions on forest ecosystem productivity , 2010, Philosophical Transactions of the Royal Society B: Biological Sciences.

[17]  S. Seneviratne,et al.  Contrasting response of European forest and grassland energy exchange to heatwaves , 2010 .

[18]  N. Buchmann,et al.  Contribution of advection to the carbon budget measured by eddy covariance at a steep mountain slope forest in Switzerland , 2010 .

[19]  N. Buchmann,et al.  Link between continuous stem radius changes and net ecosystem productivity of a subalpine Norway spruce forest in the Swiss Alps. , 2010, The New phytologist.

[20]  S. Seneviratne,et al.  Investigating soil moisture-climate interactions in a changing climate: A review , 2010 .

[21]  N. Buchmann,et al.  Management and climate impacts on net CO2 fluxes and carbon budgets of three grasslands along an elevational gradient in Switzerland , 2010 .

[22]  Christian Körner,et al.  Phenology Under Global Warming , 2010, Science.

[23]  Felix Naef,et al.  More frequent flooding? Changes in flood frequency in Switzerland since 1850 , 2010 .

[24]  N. Buchmann,et al.  Response of temperate grasslands at different altitudes to simulated summer drought differed but scaled with annual precipitation. , 2009 .

[25]  C. Spirig,et al.  Assessment of the nitrogen and carbon budget of two managed temperate grassland fields , 2009 .

[26]  H. Wanner,et al.  Tree phenology and carbon dioxide fluxes - use of digital photography for process-based interpretation at the ecosystem scale , 2009 .

[27]  Markus Reichstein,et al.  Temporal and among‐site variability of inherent water use efficiency at the ecosystem level , 2009 .

[28]  N. Buchmann,et al.  Conditional CO 2 flux analysis of a managed grassland with the aid of stable isotopes , 2009 .

[29]  Fredrik Lagergren,et al.  Storms can cause Europe‐wide reduction in forest carbon sink , 2009 .

[30]  Hyojung Kwon,et al.  Spring drought regulates summer net ecosystem CO2 exchange in a sagebrush-steppe ecosystem , 2008 .

[31]  Thomas Foken,et al.  Quality control of CarboEurope flux data – Part 2: Inter-comparison of eddy-covariance software , 2007 .

[32]  J. Fuhrer,et al.  The carbon budget of newly established temperate grassland depends on management intensity , 2007 .

[33]  Markus Reichstein,et al.  Evidence for soil water control on carbon and water dynamics in European forests during the extremely dry year: 2003 , 2007 .

[34]  T. Vesala,et al.  Reduction of ecosystem productivity and respiration during the European summer 2003 climate anomaly: a joint flux tower, remote sensing and modelling analysis , 2007 .

[35]  T. Andrew Black,et al.  Impact of changing soil moisture distribution on net ecosystem productivity of a boreal aspen forest during and following drought , 2006 .

[36]  C. Frei,et al.  Future change of precipitation extremes in Europe: Intercomparison of scenarios from regional climate models , 2006 .

[37]  P. Ciais,et al.  Europe-wide reduction in primary productivity caused by the heat and drought in 2003 , 2005, Nature.

[38]  T. Vesala,et al.  On the separation of net ecosystem exchange into assimilation and ecosystem respiration: review and improved algorithm , 2005 .

[39]  D. Lüthi,et al.  The role of increasing temperature variability in European summer heatwaves , 2004, Nature.

[40]  Mark A. Bacon,et al.  Water use efficiency in plant biology , 2004 .

[41]  J. Christensen,et al.  Climate modelling: Severe summertime flooding in Europe , 2003, Nature.

[42]  Wenjun Chen,et al.  Increased carbon sequestration by a boreal deciduous forest in years with a warm spring , 2000 .

[43]  T. Foken,et al.  Tools for quality assessment of surface-based flux measurements , 1996 .

[44]  Walter Senn,et al.  A cospectral correction model for measurement of turbulent NO2 flux , 1995 .

[45]  K. G. McNaughton,et al.  Stomatal Control of Transpiration: Scaling Up from Leaf to Region , 1986 .

[46]  E. K. Webb,et al.  Correction of flux measurements for density effects due to heat and water vapour transfer , 1980 .