Plant diversity, composition, and rarity in the southern boreal peatlands of Manitoba, Canada

Abstract

Plant diversity and rarity have been relatively well studied for bryophytes in Canadian western boreal peatlands, but little information exists for vascular plants. Diversity, community composition, and rarity of bryophytes and vascular plants were determined and relationships examined among these and environmental variables in five peatland types at Duck Mountain, Manitoba: wooded bogs, black spruce swamps, wooded moderate-rich fens, open moderate-rich fens, and open extreme-rich fens. Total diversity was 298 species comprising 86 bryophytes and 212 vascular plants. Mean diversity followed a unimodal distribution over a bog – rich fen gradient. Wooded moderate-rich fens (59.0) and black spruce swamps (53.4) had the highest mean diversity, whereas wooded bogs (32.3) and open extreme-rich fens (34.7) had the lowest mean diversity. Occurrences of locally rare species followed the same general pattern, and provincially rare vascular plants were found primarily in wooded moderate-rich fens and black spruce swamps and were mostly orchids. Reasons for these patterns are complex, but high diversity appears to be related to high habitat heterogeneity and moderate environmental variables, e.g., pH and alkalinity, and low diversity appears to be related to environmental extremes, e.g., pH and alkalinity. Boreal wooded moderate-rich fens and black spruce swamps have comparatively high plant diversity and rarity and require consideration if the focus is biodiversity conservation. This will become increasingly important in landscapes where development pressures are high.

Regional and Vegetation-Ecological Patterns in Northern Boreal Flark Fens of Finnish Lapland: Analysis from a Classic Material

“…The high species richness of the heath plot is best explained by the high environmental heterogeneity of the site. Environmental heterogeneity (occurrence of microhabitats) has been shown to correlate positively with the species richness in various habitats (Eriksson et al 1995, Locky & Bayley 2006, Økland et al 2008, Vitt et al 1995, Whitehouse & Bayley 2005.…”

Plant diversity in wooded moderate-rich fens across boreal western Canada: an ecoregional perspective

“…Compared to other peatland types, WM-R fens have the greatest plant diversity (Vitt et al 2003;Locky and Bayley 2006) and they are commonly forested with marketable size trees Locky and Bayley 2007). For this study, sites were chosen in the Mid-Boreal Uplands Ecoregion at Utikuma Lake, Alberta (AB), Prince Albert National Park region, Saskatchewan (SK), and Duck Mountain, Manitoba (MB) (Fig.…”

“…Generally, these variables have been compared over regions of varying size in different peatland types (Vitt and Chee 1990;Anderson et al 1995;Vitt et al 1995;Locky et al 2005;Locky and Bayley 2006). Glaser (1992) examined patterns of plant community composition or diversity within using bogs at the landscape scale, but not at the ecoregion scale with discrete boundaries.…”

“…Wooded moderate-rich (WM-R) fens are one of the most common wetland types across the boreal plain of western Canada (NWWG 1988;Locky 2005), with comparatively discrete abiotic and plant community attributes Locky and Bayley 2006). They also have the highest diversity (i.e., richness and rarity) of bryophytes and vascular plants (Locky and Bayley 2006).…”

“…They also have the highest diversity (i.e., richness and rarity) of bryophytes and vascular plants (Locky and Bayley 2006). The purpose of the present study is to examine patterns of environmental variables and aspects of the plant community in a single wetland type, WM-R fen, in three locations along a longitudinal and a latitudinal transect within the Mid-Boreal Uplands Ecoregion of Canada.…”