2006-11-08 15:16:01 · 5 answers · asked by Kate L 1 in Environment
Its a natural filter. The way it works is very simple. Rivers empty into flat land areas, usually near the shore. The river water also brings with it a lot of residue including silt, rocks and sand. This forms landfill which is basically just a very soft, spongy land. This is what becomes marshland. The future water coming down streams has to pass through this shallow marshland and as it does, these marshes act as filters and absorb the wastes and the toxins naturally. This works perfectly provided we don't over-abuse it by dumping excess waste up-river before the water reaches the marshes.
Marshes are also excellent food sources and thus breeding grounds for wildlife. Especially for migrating birds. This is why you will see a lot of wildlife and bird sanctuaries near marshes. Its just nature's way of balancing things.
2006-11-08 15:32:42 · answer #1 · answered by Chandru M 6 · 0⤊ 0⤋
A marsh has lots of exchanges going in it. It binds up the waste in the water and replaces it with the O in H2O and releases H. Layers upon layers of this is going on and it is amazing.
2006-11-08 23:25:53 · answer #2 · answered by Robin M 2 · 0⤊ 0⤋
A marsh has special bacteria that breaks down harmful substances into basic bio degradable components.
2006-11-09 06:16:39 · answer #3 · answered by Taurus 5 · 0⤊ 0⤋
Here is some good information on constructed wetlands (manmade). Be careful when reading about these systems, they are very good for replacing small full scale systems, but can not replace systems such as those found in large cities or large industries. They take up room and are hard to scale up.
2006-11-09 02:07:18 · answer #4 · answered by Peter Boiter Woods 7 · 0⤊ 0⤋
I'm sure your book can explain it
2006-11-08 23:18:11 · answer #5 · answered by Anonymous · 0⤊ 0⤋