Tributary of the Torrens River, north-west from Mount Pleasant
2011 Aquatic Ecosystem Condition Report
- Dry in autumn and spring 2011
- Likely to be enriched with nutrients and fine sediment when wet due to the surrounding land use
- Riparian vegetation limited to pine trees, rushes and grasses
- Moderately eroded banks in spring due to recent pine logging adjacent to the site
About the location
This creek is a small, first-order tributary in the Southern Mount Lofty Ranges that rises in the Mount Crawford Forest and flows in a south-easterly direction before discharging into the Torrens River downstream from Mount Pleasant. The monitoring site was located on a track off Glen Devon Road, about 3 km north-west from Mount Pleasant. The major land uses in the 71 hectare catchment are stock grazing, pine forestry and areas of remnant native vegetation.
The creek was given a Poor rating because the site sampled showed evidence of major changes in ecosystem structure, and moderate changes to the way the ecosystem functions. There was considerable evidence of human disturbance including the presence of moderately eroded banks following the commencement of pine-logging operations and a limited riparian zone that provides an ineffective buffering role for the creek from the adjacent land uses.
The sediments were dominated by detritus and clay with bedrock and boulders also present. Samples taken from below the surface were grey in colour and showed no indications that the sediments were recently anaerobic, or lacking in oxygen. Over 10 metres of banks showed evidence of erosion due to runoff from trucks accessing and removing some of the surrounding pine forest near the creek.
No evidence of dried algae was noted and the only aquatic plants recorded from the channel were patches of rushes (Juncus), sedges (Isolepis) and pennywort (Hydrocotyle).
The surrounding vegetation at the site was pine forest with some patches of gum trees also present.
Special environmental features
Pressures and management responses
|Widespread introduced trees and weeds in the riparian zone at the site and upstream (reducing habitat quality).||The Adelaide and Mount Lofty Ranges NRM Board has several pest plant (weed) mitigation and control programs. They work closely with landholders to control weeds on their property and to help stop the spread to other properties and waterways.|
|Limited riparian zone vegetation at the creek and upstream (reducing habitat quality, increasing sediment erosion).||The Adelaide and Mount Lofty Ranges NRM Board’s land management program encourages and promotes managing land to improve water quality. This includes incentives for revegetation programs around waterways and wetlands and stock exclusion as well as educating landholders about the importance of riparian vegetation in managing soil erosion.|
This aquatic ecosystem condition report is based on monitoring data collected by the EPA. It was prepared with and co-funded by the Adelaide and Mount Lofty Ranges NRM Board.