Flora und vegetation of abandoned clay pits and of urban areas

Early stage of bush encroachment on an upland pasture

Bryophytes are often among the first pioneers, here weather moss Funaria hygrometrica (together with Octospora excipulata, a fungus parastising it)

Succession research allows us to witness how species communities emerge and are replaced again. Initial »settlers« arrive where – by natural processes or human impact – open soil, wounded bark, blank rock surface (… or also concrete surface!) have been created. Such early succession species will then be replaced by successors based on specific processes, sequences, species identity, and species traits, which all are the field of succession research. Here, we focus on vegetation processes in clay pits and in urban sites.

Though clay is a component of soils, it is much less intensively colonised by organisms than the overlaying humus material. When this top soil is removed what remains is, therefore, a surface set (± completely) »to zero«. Similarly »empty« sites (such as graveled tracks, artificial embankments, pavements, or spoil heaps) are frequently created in infrastructural areas, e.g., along roads or in towns. In contrast to the humus-rich top soil, clay holds no or only very sparse seed banks, and open clay sites thus can be recolonised completely anew. This makes it possible to study succession processes of different stages in order to get insights in species communities, species turnover, and succession series. Clay surfaces are colonised rather slowly and can, therefore, provide long-lasting bare soil patches which, in turn, facilitate occurrences of both, low-competetitive species and neophytes, whose ecological demands can then be studied especially well.

Selected Publications

Besl H., Zitzmann H., Simmel J. (2018):
Die urbane Pilzflora von Regensburg. Regensburger Mykologische Schriften. 18: 3-140
Simmel J., Gleixner C. (2015):
Sistotrema confluens Pers. : Fr., ein humusfliehender Mykorrhiza-Bildner – Störung als Pflegemaßnahme für Pilze. Mycologia Bavarica. 16: 71-83
Simmel J. (2012):
Erechtites hieraciifolius weiter in Ausbreitung. Hoppea, Denkschr. Regensb. Bot. Ges.. 73: 191-193