Publikationsdatum:
2015-06-04
Beschreibung:
The physical and hydrological conditions in extracted peatlands often act as barriers to the regeneration of the keystone peat-forming genus Sphagnum . Although previous work has suggested that Sphagnum mosses regenerating on cutover peat surfaces quickly become vulnerable to water stress as the thickness of the regenerated layer increases, uncertainties regarding the storage and transmission properties of this layer and how these might evolve over time have made this assertion difficult to evaluate. This study investigates the hydrophysical properties and hydrological behaviour of regenerating Sphagnum layers ranging from 3-43 years in age using both field and laboratory methods. The 〉40 year old regenerated layers had significantly (p 〈 0.001) higher bulk density and retention capacity in the 5 cm thick basal layer directly overlying the cutover peat than the newer (〈10 year old) regenerated layers. Capillarity was a much stronger control on surficial water content (θ) than precipitation, which was poorly retained in the Sphagnum canopy, suggesting that regulation of water table position is an effective method of controlling θ as a means of optimizing productivity. In general, the θ sustained at a given water table position decreased as regenerated layer thickness increased. Analysis of water table position relative to the former cutover peat surface in different areas of the site suggests that the soil water dynamics of the 〉40 year old regenerated layers may be becoming increasingly similar to those of a natural bog peatland. This article is protected by copyright. All rights reserved.
Print ISSN:
0885-6087
Digitale ISSN:
1099-1085
Thema:
Architektur, Bauingenieurwesen, Vermessung
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Geographie
