http://cfs.nrcan.gc.ca/authors/read/21379?format=title Publications by H.A. Cole en-ca 2009-05-14 00:00:00 MST 2009-05-14 00:00:00 MST webmaster@nofc.cfs.nrcan.gc.ca http://cfs.nrcan.gc.ca/publications?id=29490 The Green River spacing trials were established between 1959 and 1961 to study the long-term growth and development of balsam fir (Abies balsamea (L.) Mill.) and red spruce (Picea rubens Sarg.) in response to precommercial thinning (PCT). Three nominal spacings (1.2 m, 1.8 m, 2.4 m) and an unthinned control were applied in a randomized complete block design with 5 replicates to regenerating stands, an average of 8 years after harvest. Our study examines floristic diversity associated with these treatments approximately four decades later. Floristic diversity was assessed with several alpha diversity indices as well as multivariate analysis to compare community compositino. Specific a priori contrasts compared plant diversity among a) control and average of the wider spacings (1.8 m and 2.4 m), b) control and the narrowest spacing (1.2 m), and c) the narrowest spacing and the widest spacing. Our results indicate that there were no appreciable differences among the treatments across all measures of plant diversity investigated. As such, we conclude that the forest understory, as represented by the unthinned plots, was analogous in the thinned plots at time of stand maturity. Vegetation response to PCT treatments is inconsistent in the published literature, but this can be attributed to differences in thinning intensities, recovery age or the type of forest ecosystem studied. We conclude that PCT is a variable silvicultural tool that could be used to attain both economic productivity and biodiversity conservation goals. Thu, 14 May 2009 http://cfs.nrcan.gc.ca/publications?id=29490 http://cfs.nrcan.gc.ca/publications?id=29176 As forest management intensifies, the conservation of forest biodiversity is a growing concern. Bryophytes are known to represent a considerable portion of plant diversity within northern forests. This is because bryophyte diversity is closely associated with microhabitat diversity. In this study, the influence of microhabitats on bryophyte diversity was investigated by comparing eight different boreal mixedwood microhabitats. The results indicate that bryophyte diversity (species richness, abundance, and evenness) is quite variable among microhabitats. The accumulation of species richness with microhabitat quantity within a forest stand also varies among microhabitats. ß-diversity analyses indicate that the variety of microhabitats has considerable influence on community structure. Frequency analysis identified bryophytes that are restricted to or prefer particular microhabitats. Although all microhabitats are important to bryophyte diversity, decayed logs and rocks supported the greatest number of microhabitat-specific species, and rock microhabitats supported the largest total number of species. Recommendations for forest management, one of which emphasizes the need to recognize and manage the natural variety of microhabitats, such as downed woody material, found within the forests to conserve or restore bryophyte diversity are provided. Thu, 08 Jan 2009 http://cfs.nrcan.gc.ca/publications?id=29176