New records of ostracods and ammonites from the Aalenian (mainly Concavum Zone) of the Zollernalb (Swabian Alb, SW Germany)

The lithostratigraphy and ammonite/ostracod biostratigraphy and the accompanying fauna of several sections and outcrops around the Hohenzollern (Zollernalb, SW Germany), ranging from the topmost Opalinuston Formation (uppermost Lower Aalenian) to the basal Wedelsandstein Formation (lowermost Lower Bajocian) are described and analyzed. The study of ostracods from 41 samples from the Aalenian and Lower Bajocian of the Heiligenbach, Hausterberg and Roschbach sections has yielded approximately 4,100 specimens. Significant changes in the ostracod assemblage occur at the base of the Lower Aalenian “Comptum” Subzone, at the Bradfordensis/Gigantea subzonal boundary, at the Bradfordensis/Concavum zonal boundary and at the Aalenian/Bajocian boundary (Concavum/Discites zones). A minor change occurs above the Calceola-Bank within the Concavum Zone. The following new ostracod species are described: Cytheropterina crassicostatasp. nov., Eucytherura ebertisp. nov. and Eucytherura foveolatasp. nov. In addition, 15 presumably new species are briefly described; 10 ‘incertae sedis’ taxa are figured, but left in open nomenclature. The ammonite faunas of the Inopernabank and Konglomeratbank beds (Upper Aalenian, Bradfordensis Zone, Gigantea Subzone) as well as the ammonite faunas from the Calceolabank and Rostrote Kalkbank beds (Upper Aalenian, Concavum Zone, Concavum Subzone, cavatum biohorizon) are described and correlated with those of other areas.

Calcerous Tufa as Invaluable Geotopes Endangered by (Over-)Tourism: A Case Study in the UNESCO Global Geopark Swabian Alb, Germany

Calcerous tufa and sinter are among the most impressive natural spectacles in karst landscapes whose scientific and aesthetic value is universally recognized. Being visually often very appealing they attract numerous visitors. At the same time tufa landforms are extremely vulnerable and can be seriously damaged even by minor interference. The challenge is, therefore, to protect the calcerous tufa heritage, to communicate its values, and to enhance it with the help of adequate geotourism offers. Tufa geotopes are an essential part of the geological heritage of the UNESCO Global Geopark Swabian Alb in Southwest Germany. Unfortunately tufa landforms, especially tufa cascades, suffer serious impairments by (over-)tourism, particularly during the Corona pandemic. The article explores where best to strike the balance between valorization and protection, as well as how to ensure that growth in tourism is compatible with nature preservation, especially in the case of the extremely vulnerable tufa geotopes.

Geoheritage and Geotourism in Regions with Extinct Volcanism in Germany; Case Study Southwest Germany with UNESCO Global Geopark Swabian Alb

Geotourism has become more popular in recent decades. Volcanism is an essential part of geoheritage and attracts a high number of visitors. In contrast to active volcanism, Tertiary volcanism is often not identified as such by a lay audience and is understandably perceived as less spectacular. The challenge is therefore to protect the volcanic heritage, to communicate its values, and to enhance it with the help of adequate geotourism offers. Germany does not have active volcanism, but a very high quality volcanic geological heritage, especially from the Tertiary period. Fortunately, this heritage is being increasingly valued and presented in an attractive way for a lay audience. The two Geoparks in the Eifel (Rhineland-Palatinate) are pioneers in this field. The UNESCO Global Geopark Swabian Alb actually offers a well camouflaged potential. The Swabian volcano, with an area of 1600 km2, is one of the most important tuff vent areas on earth, but hardly known outside of expert groups. A comprehensive strategy for the geotouristic valorization of the Tertiary volcanic phenomena does not yet exist in the Geopark Swabian Alb.

Surrounding landscape structures, rather than habitat age, drive genetic variation of typical calcareous grassland plant species

Context Land use change reduced calcareous grasslands throughout Europe during the last decades. Subsequent fragmentation and habitat deterioration led, moreover, to a massive biodiversity decline. To counteract this alarming development, a clear understanding of genetic variation patterns, as fundamental level of biodiversity, becomes inevitable. Objectives The aim of our study was to identify the drivers of genetic variation in common calcareous grassland plant species. More specifically, we tested whether genetic diversity or differentiation of Asperula cynanchica, Campanula rotundifolia, and Linum catharticum depend on habitat age, landscape structure, habitat quality, and/or population size. Methods We investigated 912 individuals, 304 per study species, from 19 calcareous grasslands across the Swabian Alb in Baden-Württemberg (Germany) using AFLP analyses. Results We observed no significant influence of habitat age on genetic diversity and differentiation. Habitat quality also had no impact on genetic diversity and population size only showed weak effects. However, genetic diversity strongly depended on landscape structure represented by distance to the nearest settlement, total area of surrounding calcareous grasslands, and their connectivity. Conclusions Migratory sheep herding is considered as main land use in calcareous grasslands on the Swabian Alb and thus, landscape structures in the study region may describe movement patterns of grazing livestock. In this study, genetic variation in calcareous grassland populations was strongly affected by surrounding landscape structures and subsequent grazing patterns. Therefore, we assume that moderate grazing intensities over the long term may increase levels of genetic diversity, whereas periods of overgrazing or abandonment could lower genetic diversity.