Seed bank and big sagebrush plant community composition in a range margin for big sagebrush

Abstract

The potential influence of seed bank composition on range shifts of species due to climat change is unclear. Seed banks can provide a means of both species persistence in an area and local rang expansion in the case of increasing habitat suitability, as may occur under future climate change. However a mismatch between the seed bank and the established plant community may represent an obstacl to persistence and expansion. In big sagebrush (Artemisia tridentata) plant communities in Montana, USA we compared the seed bank to the established plant community. There was less than a 20% similarity i the relative abundance of species between the established plant community and the seed bank. This differenc was primarily driven by an overrepresentation of native annual forbs and an underrepresentatio of big sagebrush in the seed bank compared to the established plant community. Even though we expec an increase in habitat suitability for big sagebrush under future climate conditions at our sites, the curren mismatch between the plant community and the seed bank could impede big sagebrush range expansio into increasingly suitable habitat in the future. Copyright