Plant and Soil

, Volume 372, Issue 1, pp 235–251

Precipitation variability does not affect soil respiration and nitrogen dynamics in the understorey of a Mediterranean oak woodland

  • Marjan Jongen
  • Xavier Lecomte
  • Stephan Unger
  • David Fangueiro
  • João Santos Pereira
Regular Article

DOI: 10.1007/s11104-013-1728-7

Cite this article as:
Jongen, M., Lecomte, X., Unger, S. et al. Plant Soil (2013) 372: 235. doi:10.1007/s11104-013-1728-7

Abstract

Background and aims

Future climate scenarios for the Mediterranean imply increasing precipitation variability. This study presents a large-scale water manipulation experiment simulating changes in precipitation variability, aiming at a better understanding of the effects of rainfall patterns on soil C and N cycling and understorey productivity in a Mediterranean oak woodland.

Methods

We used rain-out shelters to achieve (1) a normal dry period (7 days), and (2) a dry period increased three-fold (21 days), without altering total annual precipitation inputs.

Results

The temporal patterns of soil respiration (Rs) and soil inorganic N were not affected by treatment. However, water infiltration and N leaching increased with large infrequent watering events. Rs and soil NH4+-N correlated with soil temperature, with soil NO3-N being influenced by leaching.

Conclusions

The lack of significant treatment effects on either Rs or soil inorganic N can be explained by (1) minor differences in plant productivity between the treatments, suggesting equal plant N demand, and (2) the absence of moisture dependence of Rs and soil NH4+-N. Increased N leaching with large infrequent precipitation events may have longer-term consequences for ecosystem functioning. Our results contribute to an improved understanding of possible climate change effects on key ecosystem processes in Mediterranean ecosystems.

Keywords

Soil CO2 fluxSoil inorganic NUnderstorey vegetationMediterranean ecosystemPrecipitation manipulationClimate change

Copyright information

© Springer Science+Business Media Dordrecht 2013

Authors and Affiliations

  • Marjan Jongen
    • 1
  • Xavier Lecomte
    • 1
  • Stephan Unger
    • 2
  • David Fangueiro
    • 1
  • João Santos Pereira
    • 1
  1. 1.Instituto Superior de AgronomiaUniversidade Técnica de LisboaLisbonPortugal
  2. 2.Department of Experimental and Systems EcologyUniversity of BielefeldBielefeldGermany