Abundance of plant macrofossils, mollusca and ostracoda in sediments obtained near Tessin, north Germany

A depression filled with Late Glacial and Holocene sediments was excavated during the geological exploration and recovery of a dump area near Tessin close to Rostock, and initiated the studies of the present paper. Pebble analysis of three exposed or respectively drilled till horizons as well as pollenanalytical, carpological and faunistical studies carried out allow the stratigraphical subdivision of the Quaternary sequence of the dump area. The basal till was probably the result of dead ice decay, and was lithostratigraphically assigned to the Pomerian Stage (qw2). The palynological results of boreholes RKS 19/93 and A/92 reveal pre-Allerod and other sediments instead of the expected interweichselian deposits. Based on the palynological and carpological findings, we correlated the beginning of the late glacial development in the locality with the end of the Meiendorf-lnterstadial sensu Menke in Bock et al. (1985, doi:10.3285/eg.35.1.18). The limnic-telmatic sedimentation could be observed pollen floristically probably starting with the Meiendorf-lnterstadial (Hippophae-Betula nana-phase) followed by the Bolling-(Betula nana-B. alba s.l.-Artemisia-Helianthemum-Poaceae-phase) and the Allerad-lnterstadial [Betula alba s.l.-(Pinus)-Cyperaceae-phase] lasting up to the Younger Dryas (Juniperus-Artemisia-Poaceae-phase). Sedimentation closed during the Younger Dryas with the accumulation of fine sands. It was reactivated later during the Holocene due to the anthropogene influence (Older and Younger Subatlantic, dampness of the depression by clearing).

Aboveground community and species-specific plant biomass from the Jena Experiment (Main Experiment, year 2003)

This data set contains aboveground community biomass (Sown plant community, Weed plant community, Dead plant material, and Unidentified plant material; all measured in biomass as dry weight) and species-specific biomass from the sown species of the main experiment plots of a large grassland biodiversity experiment (the Jena Experiment; see further details below). In the main experiment, 82 grassland plots of 20 x 20 m were established from a pool of 60 species belonging to four functional groups (grasses, legumes, tall and small herbs). In May 2002, varying numbers of plant species from this species pool were sown into the plots to create a gradient of plant species richness (1, 2, 4, 8, 16 and 60 species) and functional richness (1, 2, 3, 4 functional groups). Plots were maintained by bi-annual weeding and mowing. Aboveground community biomass was harvested twice in 2003 just prior to mowing (during peak standing biomass in late May and in late August) on all experimental plots of the main experiment. This was done by clipping the vegetation at 3 cm above ground in four rectangles of 0.2 x 0.5 m per large plot. The location of these rectangles was assigned prior to each harvest by random selection of coordinates within the core area of the plots (i.e. the central 10 x 15 m). The positions of the rectangles within plots were identical for all plots. The harvested biomass was sorted into categories: individual species for the sown plant species, weed plant species (species not sown at the particular plot), detached dead plant material (i.e., dead plant material in the data file), and remaining plant material that could not be assigned to any category (i.e., unidentified plant material in the data file). All biomass was dried to constant weight (70°C, >= 48 h) and weighed. Sown plant community biomass was calculated as the sum of the biomass of the individual sown species. The data for individual samples and the mean over samples for the biomass measures on the community level are given. Overall, analyses of the community biomass data have identified species richness as well as functional group composition as important drivers of a positive biodiversity-productivity relationship.