Name:
Gaylussacia spp. / Trichophorum cespitosum / Sphagnum spp. Maritime Acidic Graminoid Bog & Fen Alliance
Reference:
NatureServe Biotics 2019
Description:
This maritime bog community occurs in the coastal region of northern New England and the adjacent maritime provinces of Canada. It has an ombrotrophic nutrient regime and occurs in both coastal bogs and as thin peat blankets over sloping bedrock (3-10% slope); the two settings may be contiguous. Most known sites are within 24 km (15 miles) of the ocean. Peat accumulation isolates this community from groundwater influence. Conditions are highly acidic, with pH usually below 5.0. There are two subtypes of this alliance. The dwarf-shrub bog contains low or matted dwarf-shrubs, often less than 20 cm tall; trees and tall shrubs are absent or at most widely scattered. Herbs are likewise sparse. The bryoid layer is essentially continuous and forms the vegetation substrate. <i>Empetrum nigrum</i> and <i>Gaylussacia dumosa</i>, often with scattered <i>Juniperus communis</i>, are the diagnostic shrubs; other bog ericads are often present, such as <i>Chamaedaphne calyculata, Kalmia angustifolia, Kalmia polifolia, Ledum groenlandicum, Rhododendron canadense</i>, and <i>Vaccinium oxycoccos</i>. <i>Rubus chamaemorus</i> is often present. Characteristic herbs include <i>Calopogon tuberosus, Drosera rotundifolia, Eriophorum vaginatum var. spissum, Rhynchospora alba, Sarracenia purpurea, Solidago uliginosa, Trichophorum cespitosum</i>, and <i>Trientalis borealis</i>. The bryophyte layer is a carpet of primarily <i>Sphagnum fuscum</i>, with other species including <i>Sphagnum rubellum, Sphagnum affine, Sphagnum flavicomans, Sphagnum magellanicum</i>, and lichens of the genus <i>Cladonia</i> (<i>Cladonia rangiferina, Cladonia arbuscula</i>, and others). The dwarf-shrubs <i>Empetrum nigrum, Gaylussacia dumosa</i>, and <i>Rubus chamaemorus</i>, the sedge <i>Trichophorum cespitosum</i>, and the moss <i>Sphagnum affine</i> differentiate this subtype.<br /><br />The sedge-dominated form occurs on the central, raised, relatively drier portions of maritime peatlands. The substrate is <i>Sphagnum</i> peat, usually saturated, and is acidic, around pH 4.5. Trees and shrubs are absent to sparse; dwarf-shrub cover is variable, from sparse to (rarely) over 80%. Even where dwarf-shrubs are abundant, however, their short stature allows the sedge lawns to visually dominate the vegetation. The bryoid layer is continuous. The peatland "lawns" are characterized by abundant <i>Trichophorum cespitosum</i>. Scattered low shrubs include <i>Gaylussacia dumosa</i> and <i>Chamaedaphne calyculata</i>, as well as occasional <i>Andromeda polifolia var. glaucophylla, Empetrum nigrum, Kalmia angustifolia, Kalmia polifolia, Ledum groenlandicum, Rubus chamaemorus</i>, and <i>Vaccinium oxycoccos</i>. Other associates include <i>Arethusa bulbosa, Calopogon tuberosus, Drosera rotundifolia, Eriophorum vaginatum var. spissum</i>, and <i>Solidago uliginosa</i>. The bryophyte layer is dominated by <i>Sphagnum rubellum</i> and <i>Sphagnum fuscum</i>, as well as <i>Sphagnum magellanicum</i> and <i>Sphagnum flavicomans</i>. Fruticose lichens characterize and distinguish this subtype and include <i>Cladonia rangiferina, Cladonia mitis, Cladonia arbuscula, Cladonia terrae-novae, Cladonia uncialis</i>, and <i>Cladonia crispata</i>. Diagnostic characters are its location in maritime peatlands and the relative abundance of <i>Trichophorum cespitosum</i> with other peatland plants. <i>Empetrum nigrum</i> and <i>Rubus chamaemorus</i> are also good indicators.
Accession Code:
urn:lsid:vegbank.org:commConcept:38768-{061563DA-9FC3-4510-8811-66D9CCA4D833}
Plot-observations of this Community Concept:
0
|
