We have lots of different types of waterways in Christchurch some are artificial and some are
natural like the Waimakariri, Otakaro and Styx rivers.
Ground water is connected to the Southern alps because all the rain comes down from the southern alps and goes into the underground rivers and into our aquifers. Springs are connected to our rivers and wetlands because after springs it flows into our rivers and wetlands . Surface and stormwater connect to the stormwater drain and rivers because the stormwater system takes water to our drains and streams.
In a river ecosystem different creatures rely on habitats to survive like the mudfish relies on mud because when there is a drought the mudfish berries it self order mud so it does not die. The mudfish and Mayfly larvae like the water cool because they like the water below 15 degrees. Water can be cool if the water is surrounded by vegetation.
There are many different indicators to a healthy river and a unhealthy river. If the water is unhealthy you will find snails and worms but not many and if the water is healthy you will find mayfly, stonefly, caddisfly and more.
If the water is unhealthy the algae will be long thick and grow long strands and if the water is healthy the algae we grow a thin layering. If the water temperature is unhealthy the water will be above 15 degrees and will carry less oxygen. If the water temperature is healthy it will be under 15 degrees and you may find mayfly, stonefly and more.
Testing our streams
Our class went to assess some local waterways. We assessed to see if the ecosystem was healthy or unhealthy. We used a trd a technical retriever device ( sieve on a stick ) which we used to fish out the invertebrates from the water. Our invertebrate survey identified what type of invertebrates were living there. We also used a clarity tube to see how clear the water was. We also used an in-stream and riparian survey on the waterways to score them. If it was 8 it means that what we were scoring is really good, if it was a 6 it was good, if it was a 4 it was ok and if it was a 2 it was bad.
Here are our results from our assessments. Dudley creek was good but could have been better because the stream flow was being slowed down by the sediment. The shade was quite good because up to half of the steam had shade. The sediment was quite bad because up to half of the steam was covered in sediment. The erosion was ok because some sides of the bank were falling into the stream.
The validity of this test is affiliated by the fact that everyone had different ideas on how healthy the water was. Some of us put that the water unhealthy and some of us said that the water was healthy.
I propose that we take the following action:
- Plant more trees to stop the sediment falling into the stream.
- To plant more native trees so the lives do not fall in.
- To drop stones to create rapids in the stream.
We should do this because we need to protect the land so that it is sustainable for future generations.