Download Flow, silt and sediment

MURDER UNDER THE MICROSCOPE
As a part of our Murder under the Microscope investigation, we need to gather information to help
solve the environmental crime.
You need to use the Internet, books, your own knowledge or speak to an adult to find answers to
the following questions.
You can write your answers in your homework book, or on a separate piece of paper.
This is an important homework task, as ALL information collected in the class will be
important.
Your topic this week is:
FLOW, SILT AND SEDIMENT
SECTION 1- What is flow?
Question 1- What does the word flow mean? Write a definition of flow that you understand.
What kind of things ‘flow’?
Question 2- Write a list of all the bodies of water that you know about. Here is a start: river,
lagoon, lake...
SECTION 2- What causes water to move?
Question 1- Does water in an estuary move?
What causes it to move?
Question 2- Does water in a billabong move?
Question 3- What words would you use to
describe the way water moves in a wetland?
Question 4- Do you think water in the picture
on the right would be moving slowly or
quickly? Why?
SECTION 3- Sediment or Silt
The Macquarie Dictionary defines sediment and silt like this:
 Sediment is matter which settles to the bottom of a liquid

Silt is earthy matter, fine sand or the like, carried by moving or running water and
deposited as sediment.
Use this information to answer the questions on the following page.
Look at each of these pictures and answer the questions (using information from the
following page).
Photo 1
Question 1- What do you think
has happened here?
Question 2- What do you think
happened after the rain?
Question 3- How do you think
this began?
Question 4- Should the farmer
that owns the paddock be
worried? Why?
Question 5- Where has all the
soil gone? Why has so much
been washed away?
Question 6- What helps keep
soil in place?
Photo 2
Question 7- What do you think has caused the
problem in this picture?
Question 8- How might this damage have been
prevented?
SECTION 4- Research
Question 1- What is meant by the word ‘turbidity’?
Question 2- What is meant by the word ‘erosion’?
Question 3- What part does oxygen play in the health of a river? Explain the effect of lack of
oxygen on plants and animals in the river.