Wetlands, both natural and man-made, play several important roles in the overall health of our river systems. In fact if it weren't for wetlands, our waterways wouldn't even function properly and would be a lot more polluted.
What is a wetland?
A wetland is just what it sounds like: an area of land that remains wet all or most of the time. Although it may not look like much at first glance, those marshy looking ponds and pools dotting our waterways are much more than a place to view during a walk!
Why are they important?
They are habitat for local wildlife
Wetlands are unique ecosystems that provide food, water and shelter for a range of plants and animals.
The regular flow of water entering into a wetland carries minerals and nutrients which enrich the area, making them productive for the growth of vegetation. Aquatic plants provide shelter for tadpoles, food and cover for nesting and resting water birds, and can be important nurseries for fish.
Visit Life in our water to learn about the widlife that call our waterways home.
They help to control flooding and erosion
Wetlands act as big sponges, soaking up and storing excess water. In heavy rains, these wetlands provide reservoirs that can store stormwater runoff and control the overflow and the velocity of the flows that exit the wetland into the Georges River.
Aquatic plants and reeds, as well as riparian vegetation along the shoreline, stabilise the banks of the wetland, protecting them from erosion.
They act as filters
If rivers are the arteries of a catchment, then wetlands are the kidneys. They perform important filtration functions, removing toxins, nutrients and sediments from waterways.
As wetlands slow the flows of water entering the system, they allow sediment and runoff to settle, stopping chemicals and nutrients occurring downstream where it can cause algal blooms and other problems.
While some aquatic plants in a wetland system might sometimes look a little “weedy”, it would be a mistake to try to get rid of them. Many of these plants perform very important functions, both for the health of the wetland habitat as well as for managing flooding and storm water overflows. See if you can spot these wetland warriors in a wetland near you:
Variable Milfoil (Myriophyllum variifolium)
Provides food, shelter and spawning or nesting sites for a variety of wildlife, including fish, frogs and birds.
Water Ribbon (Triglochin microtuberosum, Triglochin rheophilum)
A valuable component of the habitat of fish and aquatic birds.
Slender knotweed (Persicaria decipiens)
Forms dense clumps which help in stabilising the banks and providing habitat for birds.
Tall Spike Rush (Eleocharis sphacelate)
Is hollow and uses gases to inflate its stem to remain upright and provide maximum surface area for sunlight absorption for photosynthesis and flotation. It clumps to aid in protection from wind and currents.
Sea Rush (Juncus kraussi)
Stabiliser of estuary banks and riparian zones that adjoin developed areas. Prevents erosion and provides significant habitat for wildlife.
Kangaroo grass (Themeda australis)
Reduces weed invasion due to its thick clumping tendency. Also helps to retain soil moisture, create habitat for soil microorganisms, and flowers attract butterflies in summer.
Mat Rush (Lomandra longifolia)
One of the best river or creek bank stabilisers available; highly valued by ground wildlife as shelter and for nectar.
Jointed Twig-Rush (Baumea articulate)
Forms large dense clumps, provides good habitat for nesting and resting waterbirds. Its fruit is also a good food source. Good for wastewater and urban runoff management.
Water plantain (Alisma plantago-aquatica)
The fruits and leaves are eaten by animals; Can be useful in slowing or obstructing water flow.