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Oecologia

, Volume 182, Issue 3, pp 653–665 | Cite as

Effects of long-term nutrient additions on Arctic tundra, stream, and lake ecosystems: beyond NPP

  • Laura Gough
  • Neil D. Bettez
  • Karie A. Slavik
  • William B. Bowden
  • Anne E. Giblin
  • George W. Kling
  • James A. Laundre
  • Gaius R. Shaver
Concepts, Reviews and Syntheses

Abstract

Primary producers form the base of food webs but also affect other ecosystem characteristics, such as habitat structure, light availability, and microclimate. Here, we examine changes caused by 5–30+ years of nutrient addition and resulting increases in net primary productivity (NPP) in tundra, streams, and lakes in northern Alaska. The Arctic provides an important opportunity to examine how ecosystems characterized by low diversity and low productivity respond to release from nutrient limitation. We review how responses of algae and plants affect light availability, perennial biotic structures available for consumers, oxygen levels, and temperature. Sometimes, responses were similar across all three ecosystems; e.g., increased NPP significantly reduced light to the substrate following fertilization. Perennial biotic structures increased in tundra and streams but not in lakes, and provided important new habitat niches for consumers as well as other producers. Oxygen and temperature responses also differed. Life history traits (e.g., longevity) of the primary producers along with the fate of detritus drove the responses and recovery. As global change persists and nutrients become more available in the Arctic and elsewhere, incorporating these factors as response variables will enable better prediction of ecosystem changes and feedbacks in this biome and others.

Keywords

Fertilization Habitat Light Oxygen Temperature 

Notes

Acknowledgments

We thank Josh Beneš and Fiona Jevon for help with data collection and summaries. Constructive comments by Phaedra Budy, Just Cebrian, Elsa Cleland, Byron Crump, Jennie McLaren, and Ed Rastetter improved earlier versions of the manuscript. The Arctic LTER is funded by the National Science Foundation in multiple grants to the Marine Biological Laboratory including DEB-1026843.

Author contribution statement

LG conceived of the study and wrote the manuscript with NB and KS. All co-authors contributed essential ideas, data, and specific analyses that were critical to the development of this manuscript and edited the manuscript as it evolved.

Supplementary material

442_2016_3716_MOESM1_ESM.pdf (1.2 mb)
Supplementary material 1 (PDF 1278 kb)

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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  1. 1.Department of Biological SciencesTowson UniversityTowsonUSA
  2. 2.Cary Institute for Ecosystem StudiesMillbrookUSA
  3. 3.University of Michigan Biological StationAnn ArborUSA
  4. 4.Rubenstein School of Environment and Natural Resources, University of VermontBurlingtonUSA
  5. 5.Marine Biological Laboratory, Ecosystems CenterWoods HoleUSA
  6. 6.Department of Ecology and Evolutionary BiologyUniversity of MichiganAnn ArborUSA

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