Soil seed banks and restoration potential of tussock sedge meadows after farming in Changbai Mountain, China

Abstract

Vast tracts of the wettest agricultural fields have been abandoned worldwide, hence knowledge of their restoration potential is becoming important. Soil seed banks can be important components of ecological restoration, particularly if the seeds of key structural dominants can survive periods of cultivation. In Changbai Mountain, China, we compared the seed banks and standing vegetation between natural sedge meadows and adjacent paddy fields under drained and flooded conditions. The tussock-forming sedge Carex schmidtii dominated plant communities in the natural sedge meadows. However, this key structural dominant species was not found in the paddy fields. Other important wetland species survived cultivation as seeds (e.g. Cyperus fuscus, Lythrum salicaria and Sagittaria trifolia). Species of various life history types require either drawdown (emergent; e.g. C. schmidtii) or flooding (e.g. Potamogeton pectinatus) for successful germination. This study indicates that the seed banks of farmed sedge meadows could contribute towards the establishment of new wetland vegetation assemblages. Active revegetation of sedge meadow, particularly the native tussock-forming Carex, and changes in environmental conditions are necessary to support the region’s biodiversity.