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
Many lichens do not like air pollutionThere are many types of air pollution:o Smoke from chimneyso Car fumeso Dust and fertiliser from fieldso Fumes from factories and power stationsAll 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 Parmelia family – brown, yellow-green Xanthoria – Physcia – with and grey-green leafy lichens – have orange leafy longish hairs short hairs on their underside lichens on the edges• Bushy lichensEvernia - Green top &White underside Usnea – like a Hypogymnia – a puffy wirey beard lichen with no hairs
Our air- monitorlichens will tell us howclean our air is.
Looking for our lichens - 1 • 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 - 2• We are going to look for the 1 2 3 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 1 2 3 half a sheet of A4• 3 = enough lichens to cover a A4 sheet of whole sheet or more paper
Looking for our lichens - 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.
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 tothe OPAL air survey web pages - http://www.opalexplorenature.org/