Frequent inundation helps counteract land use impacts on wetland propagule banks. Issue 3 (7th February 2017)

• Record Type: Journal Article
• Authors: Dawson, Samantha K.; Kingsford, Richard T.; Berney, Peter; Keith, David A.; Hemmings, Frank A.; Warton, David I.; Waters, Cathy; Catford, Jane A.
• Editors: Hölzel, Norbert
• Is Part Of: Applied vegetation science. Volume 20:Issue 3(2017:Jul.)
• Page Start: 459
• Page End: 467
• Publication Date: 2017-02-07
• Subjects: Agricultural impacts -- Assisted natural restoration -- Environmental flows -- Exotic plant invasion -- Flood regime management -- Floodplain wetland vegetation -- Flow regulation -- Land use -- Regulated river -- Soil seed bank -- Wetland restoration; Plant ecology -- Periodicals; Plant communities -- Periodicals; Plant populations -- Periodicals; Nature -- Effect of human beings on -- Periodicals; 581.705
• DOI: 10.1111/avsc.12295
• Languages: English
• ISSNs: 1402-2001

Abstract

Abstract: Question: How do contrasting influences of inundation and historical land uses affect restoration of soil propagule bank composition in floodplain wetlands? Location: Northern Nature Reserve (large ephemeral floodplain), Macquarie Marshes, New South Wales, Australia. Methods: We conducted germination assays on soil samples collected from fields with different land‐use histories, stratified along an inundation gradient. We used GLM to determine whether native and exotic species richness and abundance varied along gradients of inundation and land use. Results: Species richness and plant abundance in soil propagule banks were positively related to inundation and negatively related to intense historic land use. The abundance of native species was significantly higher in more frequently inundated areas. Abundances of exotic and ruderal species were higher in areas of intense prior land use. Overall species richness was generally similar across land‐use histories. Conclusions: Land‐use legacies compromised the ability of propagule banks to rejuvenate native vegetation in this floodplain wetland, especially in less frequently flooded parts of the floodplain, which harboured more ruderal and exotic species. Negative effects of prior land use may be alleviated by increased inundation. Native soil propagule banks were remarkably intact, providing a reservoir for restoration of wetland vegetation, even in soils highly disturbed by up to 20 yr of agricultural cropping. With appropriate inundation, soil propagule banks in less degraded areas of the Macquarie Marshes can provide diverse mixtures of desired species in high abundance but, in highly degraded areas, full restoration may be delayed. Abstract : We conducted germination assays on soil samples collected from fields with different land use histories, stratified along an inundation gradient. Land use legacies compromised the ability of propagule banks to rejuvenate native vegetation in this floodplain wetland, especially in less frequently flooded parts of the floodplain. Negative effects of prior land use may be alleviated by increased inundation.