Open AccessEffects of summer grazing by reindeer on composition of vegetation, productivity and nitrogen cycling
Author(s) -
Olofsson Johan,
Kitti Heidi,
Rautiainen Pirjo,
Stark Sari,
Oksanen Lauri
Publication year - 2001
Publication title -
ecography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.973
H-Index - 128
eISSN - 1600-0587
pISSN - 0906-7590
DOI - 10.1034/j.1600-0587.2001.240103.x
Subject(s) - tundra , grazing , graminoid , vegetation (pathology) , productivity , environmental science , ecology , biomass (ecology) , cycling , plant community , primary production , steppe , agronomy , ecosystem , ecological succession , biology , geography , forestry , medicine , macroeconomics , pathology , economics
In this study, we investigated the effect of reindeer grazing on tundra heath vegetation in northern Norway. Fences, erected 30 yr ago, allowed us to compare winter grazed, lightly summer grazed and heavily summer grazed vegetation at four different sites. At two sites, graminoids dominated the heavily grazed zone completely, while ericoid dwarf shrubs had almost disappeared. In the other two areas, the increase of graminoids was almost significant. At one of the sites where graminoids dominated the heavily grazed area, we also measured plant biomass, primary production and nitrogen cycling. In this site, heavy grazing increased primary production and rate of nitrogen cycling, while moderate grazing decreased primary production. These results were inconsistent with the view that the highest productivity is found at intermediate grazing pressure. These results rather support the hypothesis that intensive grazing can promote a transition of moss‐rich heath tundra into productive, graminoid‐dominated steppe‐like tundra vegetation. Moreover the results suggests that intermittent intensive reindeer grazing can enhance productivity of summer ranges.