Plant species composition across several natural edge types in Nova Scotia

Abstract

Forest edges, anthropogenic and natural, experience edge effects which influence the surrounding species and abiotic factors. The amount of effect on the forest depends on a variety of factors including how the edge was made (or if it exists naturally), severity of contrast between adjacent habitat and forest, forest type and age. Many studies have looked in depth on anthropogenic edges but there is a lack of knowledge about natural edges, specifically looking at multiple natural edges and comparing them. My objectives were 1) to compare different edge types in Nova Scotia and 2) look at differences in species composition between the edge, forested and non-forested areas of each study. The data set used in this study spans a ten-year period and includes lakeshore, bog, barren, coastal, insect and fire edges. Cover estimates of vascular plants were taken within quadrats along a transects perpendicular to the edges and varied in length from 100 to 200m. I conducted a correspondence analysis to compare species composition. The bog, lakeshore and barren edges had patterns of distinction between the edge, forested and non-forested categories. The coastal, insect and fire sites had a lack of distinction in species composition at these three distance categories. This was related to disturbance with coastal, insect and fire being frequently/previously disturbed and thus with less complex species composition. Overlap in species composition were seen between forest and edge at all six edge types and there was also overlap with the edge and non-forested area, less so. The natural inherent sites shared more similarities to each other. The naturally created sites were not like each other nor to the naturally inherent sites. The edge and forested sites had similar species composition, as did non-forested and edge sites. The non-forested and forested species composition was distinct from each other.