How does the soil seedbank change with time since fire?

Soil seedbanks play a key role in the post-fire recruitment of many plant species.
Seedbank diversity can be influenced by spatial variability, environmental variability, and fire history (e.g. time since fire). Unlike aboveground vegetation, relationships between these factors and soil seedbank diversity remain largely unknown. 

In our new paper we partitioned the influence of spatial and environmental variability from that of time since fire (TSF) to explain how these factors interact with seedbank diversity, and ultimately to assist conservation managers in their application of prescribed burning.

We germinated soil seedbank samples from sites ranging from 1 to 75 years since fire in a heathy-woodland ecosystem across the Otway Ranges. We measured spatial and environmental variability across sites in order to partition the influence of these variables and TSF on propagules available for recruitment.

We found seedbank composition did not change considerably over time, suggesting, in this ecosystem, pre-fire age is not strongly influencing propagules available for recruitment post-fire. Our results suggest that spatial and environmental variability influence seedbank composition more than TSF.

Chick, M., Cohn, J., Nitschke, C. & York, A. (in press). Lack of soil seedbank change with time since fire: Relevance to seed supply after prescribed burns. International Journal of Wildland Fire.