Late Subatlantic history of the ombrotrophic Misten Bog (Eastern Belgium) based on high resolution pollen, testate amoebae and macrofossil analysis
Maurice STREEL,
PPP, Département de Géologie, Université de Liège, Allée du 6 Août, B18 Sart Tilman B4000-Liège, Belgium
Jérémie BEGHIN,
PPP, Département de Géologie, Université de Liège, Allée du 6 Août, B18 Sart Tilman B4000-Liège, Belgium
Philippe GERRIENNE,
PPP, Département de Géologie, Université de Liège, Allée du 6 Août, B18 Sart Tilman B4000-Liège, Belgium
Marie-Noëlle HINDRYCKX,
Didactique des sciences biologiques, Département des sciences de la vie, Université de Liège, Allée de la chimie 3, B6 CIFEN Sart Tilman B4000-Liège, Belgium
Cedric LUTHERS,
Cellule « Qualité de l’air », ISSeP, rue du Chéra 200, B4000-Liège, Belgium
Mona Court-Picon,
Earth and Life History Division, Archaeosciences Unit, IRSNB, Rue Vautier 29, B1000-Bruxelles, Belgium
Philippe FRANKARD,
Département de l'Etude du Milieu naturel et agricole, DGOARNE, Avenue Maréchal Juin 23, B-5030 Gembloux, Belgium
Mohammed ALLAN,
AGEs, Département de Géologie, Université de Liège, Allée du 6 Août, B18 Sart Tilman B4000-Liège, Belgium
Nathalie FAGEL,
AGEs, Département de Géologie, Université de Liège, Allée du 6 Août, B18 Sart Tilman B4000-Liège, Belgium
Abstract
Misten Bog has through time received homogeneous pollen rain dominated successively by Fagus, Quercus and Picea. Based on the limits separating six pollen zones across nine cores, we show that the areas of major peat production have moved with time from one side of the bog to the other. The reduction of thickness of peat was strongly dependant on the proximity of peat cutting area since the 12th Century. Before the cutting, an Alnus wood that encircled the bog regressed during the Vandal Minimum (500-800 AD) and never recovered. During this age interval, testate amoebae indicate a drier period on the peat bog. From the 12th to the 14th Centuries, there was a slight increase of non arboreal pollens linked to farming. From the 14th to the 16th Centuries testate amoebae indicate again a drier period on the peat bog but whether this is linked to climate change or human pressure is unclear. From the 16th Century onwards, Sphagnum sect. Cuspidata almost disappeared but Sphagnum imbricatum persisted until the 19th Century. Pollens linked to farming culminated again during the early part of the 19th Century. High concentration of Si, Ti and N are probably linked to the increasing farming in the neighborhood as well as to industrial mining processes in the region and might have influenced these changes on the peat bog. The theory of cyclical hollow/hummock succession versus rather stationary hummocks is discussed.
Keywords : cyclical hollow/hummock theory, Hautes-Fagnes, Little Ice Age, Medieval Warm Period, palaeoecology, Sphagnum imbricatum, stationary hummock theory, Vandal Minimum
Pour citer cet article
Maurice STREEL, Jérémie BEGHIN, Philippe GERRIENNE, Marie-Noëlle HINDRYCKX, Cedric LUTHERS, Mona Court-Picon, Philippe FRANKARD, Mohammed ALLAN & Nathalie FAGEL, «Late Subatlantic history of the ombrotrophic Misten Bog (Eastern Belgium) based on high resolution pollen, testate amoebae and macrofossil analysis», Geologica Belgica [En ligne], volume 17 (2014), number 2, URL : http://popups.ulg.be/1374-8505/index.php?id=4538.
