Sentences with phrase «tundra sites studied»
All lichen - tundra sites studied were formerly forested according to abundance of spruce charcoal at the soil surface.
http://rstb.royalsocietypublishing.org/ Not exact matches
(iv) Sites with charcoal macrofossils beneath, in, and above the current organic horizon (corresponding to the large majority of the remaining sites of the study area) are treeless stands composed of a much scattered cover (generally < 1 %) of black spruce shrubs — i.e. sites burned probably more than twice since initial forest establishment, without successful tree regeneration and currently forming lichen - shrub tundra.
Woodland and krummholz cover 30 % of the study area, whereas lichen - tundra communities occupy the remaining well - drained sites up to the highest altitude, approximately 215 m a.s.l. Several sandy lichen - tundra sites along the river bank are also occupied by sand dunes, largely controlled by fire (Saint - Laurent & Filion 1992).