A palaeoecological study of holocene peat bog sections in Germany and The Netherlands, based on the analysis of pollen, spores and macro- and microscopic remains of fungi, algae, cormophytes and animals

摘要: A Holocene peat section of the Engbertsdijksveen (The Netherlands) was analysed at centrimetre intervals for all kinds micro- and macrofossils in order to obtain maximum information regarding local vegetation animal succession regional changes prevailing types. The are illustrated, described interpreted. Among them about 70 fungal taxa, 25 least 4 algae, 15 fossils unknown identity or origin. The taxonomic designation, matrix, host- substrate specificity indicator value representatives five different groups have been tabulated. The fruit-bodies several taxa distinguished as spore types were found during macrofossil analysis, e.g., ascospores, mycelium parasite Meliola cf. niessleana (Type 14) present levels which Calluna vulgaris played a role vegetation. The ascomycete Geoglossum sphagnophilum was, according its distribution, common element bog Atlantic Subboreal periods. Zygospores Mougeotia gracillima 61) other Zygnemataceae indicate where these algae could grow bog. zygospores phases shallow, stagnant, mesotrophic open water spring. Conventional analysis pollen macro-remains with high resolution time (centimetre diagrams), above-mentioned new information, correlation events inside outside site lead following main conclusions: The Atlantic-Subboreal transition, well known elm decline, be correlated change vegetation. Following alteration wet Scheuchzeria palustris hummock period, appearance Molinia coerulea coincides decline. According ecology M. coerulea, this must caused by seasonally recurring, considerable lowering groundwater level summer. During winter rose so far that spring shallow prevailed develop. This vegetational indicates an unstable climatic period pronounced dry seasons early Subboreal. During deterioration Subboreal-Subatlantic transition incidence Corylus avellana decreased. curve shows cyclic fluctuations (1400-600 B.C.). Depressions correspond particularly (more oceanic, possibly cooler phases), maxima relatively (less warmer phases). These approximately 150–200 historical years each. increasing oceanicity ultimately resulted formation Sphagnum species Cymbifolia. In Subatlantic Cymbifolia minor constituent rubellum clearly rhizopod Amphitrema flavum. phenomenon is interpreted reflection more less oceanic period. All available data expressed curves, perhaps moisture conditions. Ther percentages plants indicating human influence low Neolithic Bronze Age. Iron Age prehistoric man important. Secale cereale already grown secondary century B.C. Population density decreased again second A.D. The study intended first step towards detailed knowledge changing ecosystems bogs forests their response environmental factors, such major cycles.