Soil Erosion

Along a Creek Bank

BY AARON WILBURN

Introduction

In this report the environmental issue of soil erosion along a creek bank is investigated. The main part of the investigation was undertaken along part of the Purga Creek. Which is situated in the area of Milbong, Queensland. This report will show people how to recognise areas that have problems with soil erosion along creek banks, the main causes and what you could do to help stop further erosion.

The Purga Creek is a subcatchment of the Bremer River Catchment which also includes the Bremer River, Western Creek, Franklin Vale Creek, Bundamba Creek and Warill Creek/Lake Moogerah. The Bremer River Catchment is also considered to be part of the Brisbane River Catchment, which is the biggest river system in Southern Queensland.

Map of the Bremer River Catchment which includes the Purga Creek.

Erosion alongside a creek is a common issue. There are a number of reasons that this environmental issue can occur-

-natural processess

-floods

-human activity ,such as land clearing

-animal activity, including cattle grazing

One of the main concerns of soil erosion is that the land along the edge of the creek can fall away into the creek which could bring down large trees. Creeks bring needed water to a landscape. In times of flood the soil can be washed away, changing the creek banks. As these pictures show.

This picture shows the creek in a time of flood, water is much higher than usual, note the flat bank.

This picture shows the bank edge changed after a flood. It now has alot of sand and dirt dumped on

it.

A flood can totally change the landscape of the creek. Also causing erosion at a fast pace by taking the creek edges to other locations. The rapid movement of water flowing and swirling around takes whatever gets in its way. Water would have to be one of the quickest ways to cause erosion, only needing a little bit of time for this to happen.

Another way that soil erosion occurs is from human activity in the form of clearing trees, native plants and grasses that help to support the edges of a creek by holding the soil down with their roots. Also allowing hoofed animals such as cattle to graze along the banks can damage the native flora and fauna.

Wind can also cause erosion. Water and Wind can carry soil into our waterways which could contain pollutants such as oil, grease, chemicals, fertilizers, animal waste and bacteria. Which in turn can threaten our water supply.

Soil erosion should be a concern for everyone.

Here are some examples of soil erosion which has caused trees to fall down.

These pictures show a large gum tree that will come down in coming years. The land has eroded away .Pic 1 shows a far away view. Pic 2 shows a close up view.

What could you do to help stop soil erosion along a creek bank. Although this is a natural process and will occur no matter what. The best things you could do is to plant native trees, bushes and grasses along the creek banks. The roots of these trees and bushes will help to hold the soil at the waters edge.

Native plants also provide habitation for native species such as birds, lizards and turtles. This can also be said for the fallen trees they also can provide a habitat for aquatic life in the creek and resting spots for birds, turtles and other animals.

Another way to help stop soil erosion along your creek bank is to provide ponds or tanks for hoofed animals such as cattle and horses and fence off the creek so these animals cannot get to the creek edges .

Another idea is to check out what the soil is made of. If the soil has higher levels of organic matter and the soil has good structure it will have greater resistance to erosion. Also Sand and loam textered soil tends to be less erodible than silt, very fine sand and some clay soils.

This picture here shows soil erosion on the side of a bank ,the exposed roots and debris are perfect places for water birds to sit and rest.

BIBLIOGRAPHY

http://en.wikipedia.org/wiki/Erosion

http://www.ipswich.qld.gov.au/residentd/healthy_life

http://www.ehow.com/how

http://www.bremercatchment.org.au