Get access

Using water plant functional groups to investigate environmental water requirements



    1. Centre for Environmental Management, University of Ballarat, Mt Helen, Vic., Australia
    2. Royal Botanic Gardens, Melbourne, Birdwood Ave, South Yarra, Vic., Australia
    Search for more papers by this author

Michelle T. Casanova, 273 Casanova Rd, Westmere, Vic. 3351 Australia. E-mail:


1. Analysis of the distribution and abundance of water plants can be a useful tool for determining the ecological water requirements of sites in a catchment.

2. Seed-bank and vegetation surveys of wetland and riparian sites were undertaken in the Angas River catchment in South Australia to determine the distribution and abundance of plants associated with riparian habitats. Plant species were allocated to water plant functional groups (WPFGs sensu Brock and Casanova, Frontiers in Ecology; Building the Links, 1997, Elsevier Science). In addition to the seven functional groups already recognised, three new groups containing submerged and woody growth forms were included in this study.

3. Cluster analysis of sites on the basis of species presence/absence was compared with site clustering obtained from analysis of representation of WPFGs. Functional group analysis provided a similar segregation of species-poor sites to that resulting from analysis of species presence/absence, but provided better resolution of clusters for species-rich sites. Three clusters of species-rich sites were delineated: riparian sites that require year-round permanent water but have fluctuating water levels, spatially and temporally variable riparian sites with shrubs and trees and temporary wetlands that dry annually.

4. Segregation of sites on the basis of functional group representation can provide information to managers about the water requirements of suites of species in different parts of the catchment. Knowledge of the environmental water requirements of sites within a catchment can help managers to prioritise water management options and delivery within that catchment.