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RESEARCH ARTICLE
Contents Vol 56(4)

Comparative ecology of two co-occurring floodplain plants: the native Sporobolus mitchellii and the exotic Phyla canescens

Ben Taylor A B D and George G. Ganf C
+ Author Affiliations
- Author Affiliations

A School of Earth and Environmental Sciences, The University of Adelaide, SA 5005, Australia.

B Present address: Department for Environment and Heritage, PO Box 1046, Mount Gambier, SA 5290, Australia.

C Co-operative Research Centre for Freshwater Ecology.

D Corresponding author. Email: taylor.ben@saugov.sa.gov.au

Marine and Freshwater Research 56(4) 431-440 https://doi.org/10.1071/MF04196
Submitted: 27 July 2004  Accepted: 1 April 2005   Published: 27 June 2005

Abstract

In the northern Murray–Darling Basin (MDB), Australia, the displacement of native floodplain grasses by Phyla canescens (Lippia), an exotic herb, coincided with a reduced frequency of floodplain inundation owing to river regulation. Although river regulation and P. canescens occur in the southern MDB, P. canescens abundance has not increased significantly since 1988. This work reports on the current distribution of P. canescens and the native grass Sporobolus mitchellii on the lower River Murray. It demonstrates that there are significant differences in the edaphic characteristics of sites occupied by the two species and co-occurrence is rare. To explain this observation, two factors were investigated: the resilience of S. mitchellii to invasion by P. canescens and the response of both species to artificial spring floods. At initial densities of >25%, S. mitchellii exhibited strong resilience to invasion by P. canescens. The growth response of both species to spring floods was similar. However, P. canescens reproduced asexually when inundated and, on exposure, exhibited a root distribution that would enhance its capacity to survive future droughts. In contrast, S. mitchellii was more tolerant of low soil moisture than P. canescens. The re-introduction of spring floods could favour the expansion of P. canescens.

Extra keywords: environmental flows, plant–plant interactions, riparian vegetation, river health, weeds.


Acknowledgments

The Murray–Darling Division, Department of Water, Land and Biodiversity Conservation provided research funding. The Environmental Analysis and Research Unit, Environmental Geographic Information, Department for Environment and Heritage provided vegetation survey data. CSIRO Land and Water provided floodplain soil and groundwater data and flooding data based on the Floodplain Inundation Model, Murray–Darling Basin Commission and River Murray Catchment Water Management Board.


References

Blanch S. J., Burns A., Vilizzi L., and Walker K. F. (1996). Ecological effects of shallow winter–spring flooding in the lower River Murray, 1995. A report to the Natural Resources Management Strategy of the Murray Darling Basin Commission. The University of Adelaide, Adelaide.

Blanch, S. J. , Ganf, G. G. , and Walker, K. F. (1999). Tolerance of riverine plants to flooding and exposure indicated by water regime. Regulated Rivers. Research Management 15, 43–62.
Braun-Blanquet J. (1965). ‘Plant Sociology. The Study of Plant Communities.’ (Hafner Publishing Company: New York.)

Bunn, S. E. , and Arthington, A. H. (2002). Basic principles and ecological consequences of altered flow regimes for aquatic biodiversity. Environmental Management 30, 492–507.
| Crossref | GoogleScholarGoogle Scholar | PubMed | Commonwealth Bureau of Meteorology (2003). ‘South Australian Climate Averages.’ (Commonwealth of Australia: Canberra. Available online at http://www.bom.gov.au/climate/averages/tables/ca_sa_names.shtml; verified May 2005.)

Craig, A. E. , Walker, K. F. , and Boulton, A. J. (1991). Effects of edaphic factors and flood frequency on the abundance of lignum (Muehlenbeckia florulenta Meissner) (Polygonaceae) on the River Murray floodplain, South Australia. Australian Journal of Botany 39, 431–443.
Earl J. (2003). The distribution and impacts of Lippia (Phyla canescens) in the Murray Darling System. Agricultural Information and Monitoring Services report for the Lippia Working Group, Gyra, Australia.

Erskine, W. D. , Terrazzolo, N. , and Warner, R. F. (1999). River rehabilitation from the hydrogeomorphic impacts of a large hydro-electric power project: Snowy River, Australia. Regulated Rivers. Research Management 15, 3–24.
Goldberg D. E. (1990). Components of resource competition in plant communities. In ‘Perspectives on Plant Competition’. (Eds J. B. Grace and D. Tilman.) pp. 27–49. (Academic Press: San Diego, CA.)

Harper J. L. (1977). ‘Population Biology of Plants.’ (Academic Press: London.)

Heard L., and Channon B. (1997). Guide to a native vegetation survey using the Biological Survey of South Australia. Geographic Analysis and Research Unit, Information and Data Analysis Branch, Department of Housing and Urban Development, Adelaide.

Houston, W. A. , and Duivenvoorden, L. J. (2002). Replacement of littoral native vegetation with the ponded pasture grass Hymenachne amplexicaulis: effects on plant, macroinvertebrate and fish biodiversity of backwaters in the Fitzroy River, Central Queensland, Australia. Marine and Freshwater Research 53, 1235–1244.
Laut P. (1977). ‘Environments of South Australia.’ (CSIRO Division of Land Use Research: Canberra.)

Long S. P. (1999). Environmental responses. In ‘C4 Plant Biology’. (Eds R. F. Sage and R. K. Monson.) pp. 215–249. (Academic Press: San Diego, CA.)

Lucy M., Powell E., McCosker R., Inglis G., and Richardson R. (1995). Lippia (Phyla canescens): a review of its economic and environmental impact on floodplain ecosystems in the Murray–Darling basin. Queensland Department of Primary Industries, Brisbane.

Maheshwari, B. L. , Walker, K. F. , and McMahon, T. A. (1995). Effects of regulation on the flow regime of the River Murray, Australia. Regulated Rivers. Research Management 10, 15–38.
Margules and Partners Pty Ltd, Smith, P., Smith, J., and Department of Conservation Forests and Lands Victoria (1990). Riparian vegetation of the River Murray. Murray–Darling Basin Commission, Canberra.

Mawhinney, W. A. (2003). Restoring biodiversity in the Gwydir Wetlands through environmental flows. Water Science and Technology 48, 73–81.
McCosker R. (1994). Lippia (Phyla nodiflora): an invasive plant of floodplain ecosystems in the Murray–Darling Basin. A report on the distribution and ecology of lippia in the lower Gwydir Valley and the Murray–Darling Basin prepared for the Gingham Watercourse Landcare Group. Department of Ecosystem Management, University of New England, Armidale.

McCune B., and Mefford M. J. (1999). ‘PC-ORD. Multivariate Analysis of Ecological Data.’ (MjM Software Design: Gleneden Beach, OR.)

Morris, K. , and Ganf, G. G. (2001). The response of an emergent sedge Bolboschoenus medianus to salinity and nutrients. Aquatic Botany 70, 311–328.
| Crossref | GoogleScholarGoogle Scholar | Rayment G. E., and Higginson F. R. (1992). Reporting of results. In ‘Australian Laboratory Handbook of Soil and Water Chemical Methods’. (Ed. R. Leydon.) pp. 311–314. (Inkata Press: Melbourne.)

Rea N. (1994). Water requirements of the Gwydir Valley wetlands – an assessment and consolidation of prior studies. NSW Department of Water Resources Environmental Studies Unit, Sydney.

Sage R. F., Meirong L., and Monson R. K. (1999). The taxanomic distribution of C4 photosynthesis. In ‘C4 Plant Biology’. (Eds R. F. Sage and R. K. Monson.) pp. 551–584. (Academic Press: San Diego, CA.)

Sher, A. A. , Marshall, D. L. , and Gilbert, S. A. (2000). Competition between native Populus deltoides and invasive Tamarix ramosissima and the implications for reestablishing flooding disturbance. Conservation Biology 14, 1744–1754.
| Crossref | GoogleScholarGoogle Scholar | Williamson G. B. (1990). Allelopathy, Koch’s Postulates, and the Neck Riddle. In ‘Perspectives on Plant Competition’. (Eds J. B. Grace and D. Tilman.) pp. 143–162. (Academic Press: San Diego, CA.)