Diasporenbanken in Böden — Grundlagen und Bedeutung

Abstract

Diaspore banks in the soil. — This paper summarizes the history, aims, methods, and results of investigations of diaspore banks in the soil. The build up of diaspore banks in the soil depends on the dispersal, burial, and type of dormancy of diaspores. Diaspore banks are reduced by germination, physiological death or death from pathogens, and predation of diaspores. Categories of transient and persistent diaspore banks are discussed and a new type of persistent diaspore bank of pioneer plants at ephemeral sites is described. Persistent diaspore banks are divided into ‘persistent’ (1–5 years) and ‘permanent’ (> 5 years). Calcareous grasslands are used as an example to show that morphological and germination characteristics of spermatophytes are related to diaspore-bank type. Diaspore banks influence the dynamics of populations and communities and should be considered in conservation programmes, e.g. to restore previous vegetation after damage or change in land use. Under intensively used forage meadows on originally oligotrophy sites and under forests on calcareous grassland sites a large proportion of species of the previous vegetation still occurs in the diaspore banks. In a raised bog different Sphagnum species could regenerate to a depth of 30 cm in the peat by spores or shoot parts although the species were absent from the above-ground vegetation.