Studies of boreal Peatland ecosystems in Britain and newfoundland

Abstract

Using the Zurich-Montpellier survey methods, 12 peatland associations were determined from Central Newfoundland and positioned along an ombrotrophic-minerotrophic gradient. For the major associations, regional floristic differences are discussed andcomparisons made with their analogous vegetation units in Northern Europe. The widespread occurrence of the associations Kalmieto-Sphagnetum fusci (raised bogs) and Calamagrostieto-Sphagnetum fusci (fen hummocks), in the study region indicate more continental conditions than experienced elsewhere on the Island. Analysis of nutrient status and related physical peatcharacteristics were undertaken for each major peatland type, with results showing a correlation between the underlying peat substrata and species composition of vegetation layer, particularly through total Ca, N, Fe, Mn and available Ca concentrations. The potential of peatland utilization in Newfoundland is discussed, and a field key for detection of associations is provided. A more intensive site analysis, emphasizing production and mineral distribution within delineated vegetation units was undertaken on Moorthwaite Moss, a small bog in Northwestern England. The vegetation units are described using Z-M techniques, and physiochemical properties determined from related peat substrata. Production analyses included estimates of peak standing crop from 7 vegetation units. Individual species performance, taken as a measure of one years growth, was determined for dominant mosses. Because of its dominance, Sphagnum recurvum studies were stressed. It was found that its growth ranged in mean length from 3.5 cm/plant (fen site) to 7.5 cm/plant (bog hollows) and in mean weight from 18.0 mg/plant (fen) to 36.0 mg/plant (bog mat). Estimates of standing crop and/or net annual production were assessed for herbs Marthecium ossifragum, Eriophorum angustifolium. Eriophorum vaginatum and shrubs Calluna vulgaris, Erica tetralix and Vaccinium myrtillus Nutrient concentrations within the main plant groups, mosses, herbs and shrubs, were determined. It was found that each group differs greatly in their demands on particular nutrients. It was further noted that a close relationship exists between nutrient content in certain plant tissues and available nutrient supplies in corresponding peat substrata.