3 Works

Data from: Urine is an important nitrogen source for plants irrespective of vegetation composition in an Arctic tundra: insights from a 15N-enriched urea tracer experiment

Hélène Barthelemy, Sari Stark, Anders Michelsen & Johan Olofsson
1. Mammalian herbivores can strongly influence nitrogen (N) cycling and herbivore urine could be a central component of the N cycle in grazed ecosystems. Despite its potential role for ecosystem productivity and functioning, the fate of N derived from urine has rarely been investigated in grazed ecosystems. 2. This study explored the fate of 15N-enriched urea in tundra sites that have been either lightly or intensively grazed by reindeer for more than 50 years. We...

Data from: Consequences of grazer-induced vegetation transitions on ecosystem carbon storage in the tundra

Henni Ylänne, Johan Olofsson, Lauri Oksanen & Sari Stark
1. Large herbivores can control plant community composition and, under certain conditions, even induce vegetation shifts to alternative ecosystem states. As different plant assemblages maintain contrasting carbon (C) cycling patterns, herbivores have the potential to alter C sequestration at regional scales. Their influence is of particular interest in the Arctic tundra, where a large share of the world’s soil C reservoir is stored. 2. We analysed how grazing mammals influence tundra vegetation and how grazer-induced...

Data from: Grazing decreases N partitioning among coexisting plant species

Hélène Barthelemy, Sari Stark, Minna-Maarit Kytoviita & Johan Olofsson
1. Herbivores play a key role in shaping ecosystem structure and functions by influencing plant and microbial community composition and nutrient cycling. 2. This study investigated the long-term effects of herbivores on plant resource acquisition. We explored differences in the natural δ15N signatures in plant, microbial and soil N pools, and examined mycorrhizal colonization in two tundra sites that have been either lightly or heavily grazed by reindeer for more than 50 years. The study...

Registration Year

  • 2017

Resource Types

  • Dataset


  • University of Lapland
  • Umeå University
  • The Arctic University of Norway
  • University of Copenhagen
  • University of Oulu
  • University of Jyväskylä
  • University of Turku