Bryophyte vegetation on spruce stumps in the Hautes-Fagnes
Cornelissen, J.H.C.; Karssemeijer, G.J.
Bryophyte vegetation on cut surfaces of Picea abies stumps was studied in the Hautes-Fagnes (Belgium) according to the Braun-Blanquet method. Two associations have been distinguished: the Lophocoleo-Herzogielletum seligeri Philippi 1965 nom. mut. (L.-H. s.) and the Tetraphidetum pellucidae Maurer 1961 (T. p.), which have been divided into two and three new subassociations respectively: L.-H. s. brachythecietosum rutabuli subass. nov., L.-H. s. cephalozietosum bicuspidatae subass. nov., T. p. riccardio-nowellietosum curvifoliae (Koppe 1956) subass. nov., T.p. calypogeietosum muellerianae subass. nov. and T.p. typicum subass. nov. Special reference was given to the relation of these five successive subassociations to the degree of wood decay. As decay parameters were used: wood roughness, wood softness, pH, water content and estimated degree of decay. For all parameters significant mutual correlations as well as correlations with the successive communities were demonstrated. There is some evidence that the process of decay gives rise to a succession of the five subassociations, of individual bryophyte species and a succession of life forms/growth forms. Some communities differ significantly in preference for moisture of the surrounding soil. Thus, a two-dimensional vegetation succession scheme could be hypothesized, including a soil-dry and a soil-moist wood decay line of succession.