lichens and pollution - an introduction
DESCRIPTION
Introductory presentation provided via the OPAL (Open Air Laboratory) project.TRANSCRIPT
Lichens and Pollution …
Is our air clean?
Activities follow the information on the OPAL air survey web pages - http://www.opalexplorenature.org/
Compiled by Jacqui Middleton, 2010.
WHAT IS A LICHEN?o Lichens are made up of two different
organisms living together: A fungus and an alga
.
o The fungus provides the body in which the alga can live protected from light and drought.
o The alga makes the food for the fungus.
Many lichens do not like air pollution
There are many types of air pollution:o Smoke from chimneyso Car fumeso Dust and fertiliser from fieldso Fumes from factories and power stations
All of these types of air pollution contain NITROGEN – many lichens do not like too much NITROGEN.
What do our air-monitor lichens look like?
• Leafy lichens
• Bushy lichens
Evernia - Green top & White underside Usnea – like a
wirey beardHypogymnia – a puffy lichen with no hairs
Parmelia family – brown, yellow-green and grey-green leafy lichens – have short hairs on their underside
Xanthoria – orange leafy lichens
Physcia – with longish hairs on the edges
Our air-monitor
lichens will tell us how
clean our air is.
• We are going to find the 4 best lichen trees in the school grounds.
• Each group will choose one tree and measure its girth using a tape measure (or a piece of string and a ruler).
Looking for our lichens - 1
Looking for our lichens - 2• We are going to look for the
different lichens on the trunk of a tree up to our heads .
• We are also going to say how much of each type of lichen is on the tree and will tell our group leader.
• 0 = no lichens• 1 = enough lichens to cover a
quarter of a sheet of A4• 2 = enough lichens to cover
half a sheet of A4• 3 = enough lichens to cover a
whole sheet or moreA4 sheet of paper
1 2 3
1 2 3
•We are going to look for lichens on twigs
•We are going to look for algae (dark green or orange powder)
•Your group leader will make a note of what you see on your group’s record sheet.
Looking for our lichens - 3
What do the results mean?• Places with clean air have
more pollution sensitive bushy lichens (e.g. Usnea and Evernia)
• Places that have a lot of nitrogen will have a lot of the orange leafy lichens (Xanthoria)
• Places that have quite clean air will have lots of the green and brown leafy lichens (Parmelias)
• If both are growing together then the air might be changing
After we come back in …
• The oldest children will set up air pollution tubes to put outside.
• Everyone else will make drawings and/or write about what we did to put up on our display or into our Wildlife Club display book.
• Please stay with your groups today.
For more information and downloads concerning these activities go to the OPAL air survey web pages - http://www.opalexplorenature.org/