Substrate Form Determines the Fate of Bryophytes in Riparian Buffer Strips

Abstract

Substrate form determines the fate of bryophytes in riparian buffer strips.Ecological Applications, http://dx.doi.org/10.1890/04-0570Access to the published version may require subscription. N.B. When citing this work, cite the original published paper. Abstract. Studies on the effectiveness of forest buffer strips left along streams after logging have long overlooked the biota of the buffers themselves, despite their high species richness. We investigated mosses and liverworts (bryophytes), abundant and species-rich groups in boreal forests, before and 2.5 years after logging along 15 small streams. In each site, two 1000-m 2 (20 ϫ 50 m) plots along the stream were inventoried; one plot in an area subjected to clear-cutting, and another in a buffer strip (10 m wide on each side of the stream). Ten plots along small streams in forest reserves in the same region were used as references. We found that less than half as many bryophyte species per plot disappeared after logging in the buffer strips compared to the clearcuts. The changes in bryophyte cover and in species composition were smaller in the buffer strips, and the species that were negatively affected in the clearcuts were less affected in the buffer strips. However, there was a significant change in species composition in the buffer strips compared to the references. Substrate form and taxonomic group were important factors in understanding this turnover. Many species growing on substrates with a convex form (e.g., logs, tree bases, and mesic ground) decreased or disappeared, while species on concave substrates were rather unaffected. This held for both mosses and liverworts, although liverworts were generally more sensitive than mosses. The difference in response of assemblages on convex vs. concave substrates makes changes in microclimate due to logging a likely explanation. The species in most need of protection (i.e., the red-listed species) were among the ones with strongest declines in the 20 m wide buffer strips. In order to function optimally for bryophyte conservation, forests along small streams need to be protected from high windthrow frequency and strong edge effects. Increasing the width of buffer strips at sites with known or potential values (e.g., large amounts of woody debris or boulders) should be considered a better strategy than using narrow buffer strips with a fixed width.

Partial harvests in the boreal forest: response of the understory vegetation five years after harvest

“…Bryophytes may be particularly sensitive to this factor, as indicated by the drop in cover in two dominant bryophytes: Pleurozium schreberi (moss) and Ptillidium ciliare (L.) Hampe (liverwort). The relatively higher sensitivity of bryophytes to changes in micro-climate has been well documented in the literature (Fenton and Frego 2005, Hylander et al 2005, Dovčiak et al 2006) and these species may be the best indicator of microclimatic change after forest harvest.…”

Slope Aspect Modifies Community Responses to Clear-Cutting in Boreal Forests

“…However, in contrast to our hypothesis 4 and to So¨derstro¨m (1981), we did not find greater richness of liverworts and species associated with wood and bark in north-facing forests. This may be an effect of our studied forests being managed and poor in convex substrates such as CWD, structures that are vital for boreal forest liverworts and wood inhabiting species (e.g., Hylander et al 2005). Consequentially, richness of these groups was low compared to that of old-growth forests also in our north-facing forests.…”

Macroinvertebrate Community Structure in Three‐Gorges Reservoir, China

“…We performed multi-response permutation procedures (MRPP), with Euclidean distance as the distance measure, to examine significant differences in community structure between groups determined by TWINSPAN. MRPP is a nonparametric statistical method for testing the hypothesis of no difference in community structure between two or more a priori groups (BESTELMEYER and WIENS, 2001;HYLANDER et al, 2005). In addition, the TWINSPAN classification results were applied as the second matrix in Detrended Correspondence Analysis (DCA).…”