Beitrag
Classification, ecological characterization and development of montane mires (Kleinwalsertal, Austria)
Schrautzer, Joachim; Bork, Hans-Rudolf; Christ, Lydia; El-Balti, Nadja; Martens, Tjark; Kempke, Max; von Scheffer, Clemens; Unkel, Ingmar
Phytocoenologia Band 49 Heft 3 (2019), p. 263 - 285
66 Literaturangaben
veröffentlicht: Oct 29, 2019
Online veröffentlicht: Jul 8, 2019
Manuskript akzeptiert: Mar 18, 2019
finale Ms. Revision erhalten: Mar 13, 2019
Manuskript-Revision angefordert: Nov 15, 2018
Manuskript erhalten: Sep 21, 2018
ArtNo. ESP024004903003, Preis: 29.00 €
Abstract
Aims: To classify and characterize montane mires and deduce management strategies based on their current state and long-term development. Location: Kleinwalsertal, Austria. Methods: Vascular plants and bryophytes were recorded in a field study of 274 relevés. Abiotic parameters (groundwater dynamics, water and soil characteristics) were measured at 35 sites. Macro-remain analyses of 42 soil profiles were used to reconstruct the long-term development of mires. Vegetation was differentiated by using conventional (Braun-Blanquet) and multivariate methods (Cluster analysis, Ordination). A combination of hydrogenetic criteria, chemical composition of peat and soil water, botanical composition of peat and current vegetation was applied to classify mire types. Results: Eight vegetation types were delimited and characterized pertaining to their ecological conditions. An acidity-alkalinity gradient was documented for the different vegetation types. Hydrological data indicated differences in human impact on mires. All transitions between soligenous, ombro-soligenous and ombrogenous mires were found along transects including shallow bogs on hilltops via base-rich fens on slopes, to transition mires at the onset and deeper bogs in the center of terraces. Analysis of short and long-term successional processes revealed that this sequence of mire types has been affected by human impacts at many locations. Thus, the discharge of base-rich subsurface water at the base of hillsides by ditches caused a) the ombrotrophication of transition mires and the expansion of secondary bog vegetation in the terraces and b) the development of straw meadows (Molinion) or wet meadows (Calthion) on the slopes at the expense of base-rich fens (Caricion davallianae). The increasing abandonment of species-rich fens is a problem for nature conservation. Conclusions: The analysis of vegetation development on various temporal scales is helpful to define restoration targets. In the study area, management should focus predominately on restoring the typical hydrology of mires and maintaining biodiversity of fen meadows by mowing or grazing. Taxonomic references: Amann (2016) for vascular plants; Schröck et al. (2013) for bryophytes. Syntaxonomic references: Mucina et al. (2016) for classes, orders and alliances; Grabherr & Mucina (1993) and Mucina et al. (1993) for associations. Abbreviations: EC (electrical conductivity), NMDS, non-metric multidimensional scaling, PMC = peat moss community, SSR = small sedge reeds.
Schlagworte
Alpine region • bog • fen • human impact • macro-remain analysis • mire classification • restoration • succession