PARENT SESSION
Contributed Oral Session 117: Biodiversity: Climate and Environmental Effects
Thursday, August 11, 8:00 AM - 11:30 AM, Meeting Room 519 A, Level 5, Palais des congrès de Montréal
Productivity gradients, range of natural variability, and bryophyte conservation in the southern boreal forest.
Frelich, Lee*,1, Janssens, Joannes2, Reich, Peter1, 1 University of Minnesota, St.Paul, MN2 Lambda-Max Ecological Research, Minneapolis, MN
ABSTRACT- Bryophyte species richness was examined on 55 0.6 ha plots in southern boreal forests of Minnesota, USA. The plots were distributed among three forest types (jack pine, aspen and black spruce) and two age classes (20-40 yr and 70-100 yr). The objectives were to examine the relationships between bryophyte species richness and environmental variables and to assess whether all forest type and age combinations are necessary to maintain bryophyte species richness. There was no relationship between bryophyte species richness and aboveground net primary productivity (ANPP), nor were there any significant differences in species richness by forest type and age. Bryophyte species richness was related to total bryophyte cover and annual litterfall (unimodal relationships), and soil depth (negative), R2 = 48.7%, p<0.001. Vascular plant richness and bryophyte richness were marginally related (r = 0.262, p = 0.053), except within the black spruce forest type (r = 0.770, p = 0.001). Despite the lack of differences in species richness among forest type and age classes, multiple response permutation procedure and indicator species analyses showed that bryophyte communities are distinct among forest types and age classes, and that bryophyte communities are more strongly tied to forest type than to ANPP. These analyses provide strong evidence that a conservation strategy for bryophytes in the boreal forest should include all forest types and age classes rather than stands along a productivity gradient.
Key words: Species richness and productivity