Lichenological evidence for the recognition of inland rain forests in western North America
- Author:
- Goward T. & Spribille T.
- Year:
- 2005
- Journal:
- Journal of Biogeography
- Pages:
- 32: 1209-1219
- Url:
Aim The coastal temperate rain forests of north-western North America are
internationally renowned as the archetypal expression of the temperate rain forest
biome. Less well documented is the existence of somewhat similar forests 500–
700 km inland on the windward slopes of the Columbia and Rocky Mountains.
Here we attempt to show that these inland ‘wetbelt’ forests warrant rain forest
status.
Location North-western North America.
Methods We use tree-dwelling macrolichens to assess the degree of
environmental congruence between the coastal temperate rain forests and their
inland counterparts.
Results We report three key findings: (1) 40% of oceanic, epiphytic
macrolichens found in Pacific coastal rain forests occur also in inland regions;
(2) epiphytic species richness decreases with decreasing latitude, such that
roughly 70% of disjunct oceanic species are restricted to regions north of 51 N;
and (3) the southward decline in lichen diversity is correlated with a parallel
decrease in summer precipitation, but not with mean annual precipitation.
Main conclusions These observations are consistent with the recognition of an
inland rain forest formation between 50 and 54 N. Inland rain forests represent a
small, biologically significant ecosystem whose continued fragmentation and
conversion to tree plantations warrant close scrutiny.
Keywords
British Columbia, climate, epiphytes, lichens, summer moisture deficit,
temperate rain forests.
- Id:
- 1241
- Submitter:
- zdenek
- Post_time:
- Tuesday, 30 November -0001 00:57