Comparison of the Ground Vegetation in Spruce Plantations and Natural Forest in the Greater Fundy Ecosystem, New Brunswick
Keywords:forestry, plantations, clear-cutting, plant communities, ground vegetation, environmental impact, New Brunswick
AbstractWe studied changes in ground vegetation associated with the conversion of natural, mature, mixed-species forest into conifer plantations in southeastern New Brunswick. This was done to determine the degree to which plant-associated biodiversity was affected by this forestry practice. Species of lichens, bryophytes, and vascular plants were examined in a 21-year chronosequence of 12 Black Spruce (Picea mariana) plantations and compared to 8 stands of natural forest of the type replaced. The richness, diversity, and density of species were greatest during younger stages of the plantation sere, with as many as 170 species occurring in a 6-year-old stand. Species occurred in successional stages according to their abilities to: (a) survive disturbances associated with clear-cutting and plantation establishment; (b) regenerate vegetatively; (c) re-establish from a persistent seedbank; (d) invade disturbed habitat by dispersed seeds; and/or (e) tolerate environmental stress imposed by the overtopping canopy during stand development. Multivariate analyses suggested that successional factors had the strongest influence on differences in the ground vegetation among stands of various ages. Gaps in the canopy of reference forest and older plantations provided microsite conditions similar to those of early seral stages, allowing some ruderal species to persist in older stands. Nonindigenous species were almost entirely limited to younger plantations. Some species of natural forest were rare or absent from plantations and may be at risk from the extensive development of these agroforestry habitats in our study region; these included Acer pensylvanicum, Cephaloziella spp., Chiloscyphus spp., Fagus grandifolia, Lepidozia reptans, Nowellia curvifolia, Odontoschisma denudatum, and Viburnum alnifolium.
Copyright for Canadian Field-Naturalist content is held by the Ottawa Field-Naturalists' Club, except for content published by employees of federal government departments, in which case the copyright is held by the Crown. In-copyright content available at the Biodiversity Heritage Library is available for re-use under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 (CC BY-NC-SA 4.0) licence. For usage of content at the BHL for purposes other than those allowed under this licence, contact us.
To request use of copyright material, please contact our editor, Dr. Dwayne Lepitzki: editor -at- canadianfieldnaturalist -dot- ca