Impacts of drought and nitrogen addition on Calluna heathlands differ with plant life-history stage

Publikation: Beiträge in ZeitschriftenZeitschriftenaufsätzeForschung

Authors

Climate change and atmospheric deposition of nitrogen (N) affect the biodiversity patterns and functions of ecosystems world-wide. While many single-factor studies have quantified ecosystem responses to single global change drivers, less is known about the interaction effects of these drivers on ecosystem functions. Here, we present the results of a three-year field and a two-year glasshouse experiment, in which we assessed responses of Calluna vulgaris heathlands to the single and combined effects of drought events (D) and N fertilization (D: 25% precipitation reduction in the field experiment and 20-50% soil water content reduction in the glasshouse experiment; N fertilization: 35 kg N ha<sup>-1 </sup>year<sup>-1</sup>). We examined the effects of D and N treatments on growth responses of the dominant dwarf shrub Calluna vulgaris (in terms of biomass production and allocation, tissue δ<sup>13</sup>C signatures and C:N ratios) in relation to two plant life-history stages and different 'ecotypes' (sub-Atlantic vs. subcontinental heathlands). Plant responses varied strongly with life-history stage, and the interaction of N and D showed lower effects than would be expected based on additive responses to single factors. While D treatments had no effects on Calluna in the building phase (ca. ten-year-old plants), seedlings (particularly one-year-old plants) were highly susceptible to drought. Differences in response patterns were attributable to the high shoot-root ratios typical of young Calluna plants. These ratios decreased with progressing life history as a result of increasing below-ground biomass investments. Below-ground biomass production and shoot-root ratios differed between plants from the different heathland sites. Tissue δ<sup>13</sup>C signatures decreased and C:N ratios increased with plant age as a result of decreasing evaporative demands (per unit root biomass). N fertilization increases the shoot-root ratios and thereby the drought susceptibility of Calluna plants. Synthesis. Our findings suggest that plant responses to global change are difficult to anticipate by means of single-factor studies or by focusing on a single life-history stage. This highlights the need for global change research to include multiple factors and life-history stages when assessing an ecosystem's susceptibility to shifts in environmental conditions.

OriginalspracheEnglisch
ZeitschriftJournal of Ecology
Jahrgang103
Ausgabenummer5
Seiten (von - bis)1141-1152
Anzahl der Seiten12
ISSN0022-0477
DOIs
PublikationsstatusErschienen - 09.2015

DOI

Zuletzt angesehen

Publikationen

  1. Konstruktive Maßnahmen zur Reduzierung der Haftreibung in tribologischen Systemen
  2. Entrepreneurship and personal initiative
  3. Misestimations as a barrier to climate action
  4. Text und Technik
  5. Infrastructures of Extraction in the Smart City Zones, Finance, and Platforms in New Town Kolkata
  6. Elbe DSS
  7. The Project Schöningen from an ecological and cultural perspective
  8. Bildersuche
  9. Realization of Data-Driven Business Models in Incumbent Companies
  10. Evaluating the effectiveness of a human factors training
  11. Prediction of roughness after ball burnishing of thermally coated surfaces
  12. Artful sustainability governance—Foundational considerations on sensory-informed policymaking for sustainable development
  13. Influence of socio-environmental risks on natural resource dependent socio-ecological systems in Central Himalaya
  14. Anger experience of cyclists in traffic
  15. Poutrus: Umkämpftes Asyl
  16. Inequality Regimes in Coworking Spaces
  17. Born to Be an Entrepreneur ?
  18. Hören, was die Maschine hört
  19. Research Gains
  20. Gesellschaftsrecht
  21. Erratum: Identity affirmation and social movement support (European Journal of Social Psychology (2007) (7) DOI10.1002/ejsp.473)
  22. Die Anwendung des Angehörigenprivilegs bei Verkehrsunfällen
  23. Bruchlinien der Raumerfahrung
  24. Die Kostenrechnung als Informationssystem der Unternehmensführung
  25. Mealtime Conversations Between Parents and Their 2-Year-Old Children in Five Cultural Contexts
  26. R&D and the agglomeration of industries
  27. PISA, NEPS und BiSta – Sind die Kompetenzmessungen in Mathematik vergleichbar?
  28. "Rebellious Subjects: The Politics of England’s 2011 Riots"
  29. Der BilWiss-2.0-Test