Heat shock increases the reliability of a temperate calcareous grassland seed bank study

Abstract

Reliable assessment of the density and species richness of the viable seeds in the soil is essential to estimate the probability of successful restoration of a particular plant community. Since temperate calcareous grasslands contain several thermophilous species typical of fire prone habitats, heat shock can be expected to break dormancy of target species for calcareous grassland restoration. We tested the effect of heat shock on the estimated density and species richness of seeds in soil samples. Heat shock treatments between 70 and 110 degrees C resulted in both a higher estimated seed density and estimated species richness, in particular of specialist calcareous grassland species. Moreover, 25 species germinated exclusively from the heat-treated samples. This indicates that several species would have been missed by handling soil seed bank samples following the standard germination protocol, resulting in an underestimation of the restoration potential

Rapid Buildup of Genetic Diversity in Founder Populations of the Gynodioecious Plant Species Origanum vulgare after Semi-Natural Grassland Restoration

“…Origanum vulgare is known to form a persistent seed bank in our study area [73]. All restored grasslands were historically grasslands before their afforestation and degradation.…”

Field burn versus fire-related cues: germination from the soil seed bank of a South American temperate grassland

“…Within the monocots, Juncus capillaceus was the most abundant species in most treatments. The species of this genus produce a large amount of small, long-lived seeds, forming large, persistent soil seed banks (Lunt, 1997; Bossuyt and Honnay, 2008). High densities of Juncus spp.…”

“…in seed banks are not exclusive to grassland soils. In a survey from very different ecosystems, Bossuyt and Honnay (2008) found that Juncus spp. were present in more than 50% of the soil seed banks analysed and were among the five most abundant species.…”

Why some species cannot colonise restored habitats? The effects of seed and microsite availability

“…However, at the species level, these same studies revealed that some plants benefit from fire treatments and some specialist species present in calcareous grassland seed banks germinate better after heat shock (e.g. Thymus pulegioides, Globularia bisnagarica) (Bossuyt and Honnay 2008).…”