Effects of large herbivores on biodiversity of vegetation and soil microarthropods in low Arctic Greenland
Aastrup,P., K. Raundrup, J. Feilberg, P. H. Krogh, N.M. Schmidt and J.Nabe-Nielsen. 2014. Danish Centre for Environment and Energy
Abstract
This report summarizes the results of a project that aims at documenting long term
effects of grazing by comparing baseline data inside and outside exclosures. We
collected data on vascular plants, mosses, lichens, microarthropod abundance and
food-web structure, soil nutrients, decomposition, and soil temperature. Data provide
a significant basis for understanding the interaction between large herbivores and
vegetation in Greenland. The report contains documentation of data collected in
2009 and 2012 as well as documentation of data from 1984-2004 made available
by Jon Feilberg.
The study took place in South Greenland, and in Akia north of Nuuk in
West Greenland. The southern Greenland localities are grazed by domestic
sheep (Ovis aries), whereas Akia is grazed by caribou (Rangifer tarandus groenlandicus).
Generally there was a high similarity in plant species composition in grazed
and un-grazed plots %u2013 even after more than 25 years. Few species only ap-
pearing inside or outside the exclosures, might indicate that grazing could
have effects on the species composition. The cover of shrubs, herbs, and lit-
ter appeared to be favoured by not being grazed.
The nutrient content in soil was similar in grazed and un-grazed plots and
generally, soil nutrients were at the same level in Akia and Kiattuut.
Generally temperatures were highest outside the exclosures and the cold
season with temperatures below 0°C was longer in Akia than in Kiattuut.
The rate of decomposition was much higher in south Greenland than in
West Greenland. The differences in decomposition rate between grazed and
un-grazed plots were not significant in both Akia and Kiattuut.
The average diversity of microarthropods was highest in plots not being
grazed.
Our dataset offers unique possibilities for analysing the relations between
grazing, climate change and biodiversity in the low Arctic. Further in-depth
analysis of the data collected will shed more light on the future effects of the
large herbivores in the Arctic.
Key Words
Vegetation, biodiversity, microarthropod, herbivores, sheep, caribou
