ESTABLISHING WETLAND PLANTS IN ARTIFICIAL SYSTEMS

Emergent macrophytes selected for growth in artificial systems should be robust in habit, have a high biomass throughout the year, and be readily available in the local area. In south-western Australia potentially useful species fall either into the class of ''sprouters'', which are readily established by rhizome transplants but not by seed; and 'seeders, which can be readily established from seed but not rhizome transplants. Seeder species occur in large populations after disturbance of natural systems; sprouter species are often more desirable in the long term, but sufficient source material can be difficult to obtain. Of nine species established in containers and then subjected to a range of water depths from 1 metre below to 0.75 metres above the sediment surface, best growth was obtained when mean water level coincided with the sediment surface. This was consistent with field observations on plantings at different mean elevations. In microsystems in plastic containers, at the same nutrient load, plant growth was reduced at slow flow rates when sediments became anaerobic.