Oral Presentation Australian Society for Limnology Congress 2013

Response of ephemeral lake vegetation to changes in water quality and water regime (#88)

Adrian Clements 1
  1. Charles Sturt University, ALBURY, NSW, Australia

Ephemeral lakes are a distinct part of the Australian environment. Discrete vegetation communities emerge in ephemeral lakes as a consequence of intermittent periods of wet and dry climates and variable water quality. This project aims to identify the ecological responses of aquatic vegetation communities to changes in water quality and water regime (both individually and in combination) in ephemeral lakes. 

The main study site is Lake Brewster, with comparisons to Lake Cowal and Lake Cargelligo, all of which are situated in the mid-section of the Lachlan River catchment, NSW. Each lake has differing levels of human use and impact. Lake Brewster is a modified ephemeral lake which has been divided into a main storage, and inflow and outflow wetlands. The former two are studied in this project.

Significant differences in the composition of the standing vegetation and seed bank have been revealed from preliminary analyses. It is hypothesised that these differences are a result of differing water quality and water regimes. Presented here is a preliminary conceptual model of the influence of water regime and water quality on aquatic vegetation communities of modified ephemeral lakes. Also presented are experimental designs for further studies into the effects of nutrients, turbidity and water regime on seed bank emergence and plant growth.