Tuesday 28th June 2016. Led by James Hill, University of Liverpool.
- What are they?
- How do I identify them?
- Why should I care?
My first encounter with lichens was on old walls and gravestones in a local church yard. These unusual organisms consist of a symbiotic association between a fungus and an alga, with both partners benefiting from the relationship. Although they are incredibly hardy organisms, surviving extremes of heat and cold as well as drought, few species can tolerate air pollution. My crustose patch of Caloplaca growing on a gravestone was the origins of my interest in lichens which was further stimulated by James Hill, MSc student from the University of Liverpool in his workshop at Merseyside Biobank.
NOTEBOOK:
Lichen biology: Own taxonomic order
- Algae & Fungi
- Photobiont & Mycobiont
- Algae = makes food/Fungi makes shelter
Lichen ecology: inherent appeal e.g. Cladonia
Ancient woodland indicators: NIEC
- Epiphytic air plant, (need trees),
- Poor colonisers, grows slowly.
- Indicator
- Forest continuity.
- Air pollution/industrial zones
- dynamic
- E.g. Lobar, Usnea, Bryoria, Cladonia.
Pollution indicators:
- Hawksworth – Rose scale
- Sulphur dioxide
- Zonation
- distinct communities = air quality, acid rain.
Pollute < > Clear
Xanthoria Evernia Cladonia Usnea
IDENTIFYING LICHENS:
- Lens, GPS, Sample bags, Guide, FSC chart.
- Field Book: “Lichens: An illustrated Guide to the British and Irish Species” by Frank Dobson, 2011.
- Chemical tests: according to Field Guide.
- Microscope: Compound x 400, ideally x 1000. To identify (1) spores (2) ascus.
PRACTICAL:
Body (thallus) types
- Leprose (powdery) e.g. Leparia
- Filamentous (beard-like) e.g. Usnea
- Fruticose (shrubby) e.g. Evernia
- Crustose (crusty) e.g. Caloplaca
- Squamulose (small leaf) e.g. Cladonia
- Foliose (big leaf)e.g. Parmelia
Sub-strates
- Living wood
- Dead wood
- Rock
- Also; some species grow on molluscs and plants.
FIELD NOTES: LICHEN BIODIVERSITY IN COURT HEY PARK SJ4190
|
|
Scientific name |
Common name |
|
1 |
Xanthoria parietina |
Common Orange Lichen |
|
2 |
Parmelia saxatilis |
Salted Shield Lichen |
|
3 |
Parmelia sulcata |
Netted Shield Lichen |
|
4 |
Physcia aipolia |
Hoary Rose Lichen |
|
5 |
Physcia adscendens |
Hooded Rosette Lichen |
|
6 |
Physcia tenella |
= |
|
7 |
Evernia |
Oakmoss |
|
8 |
Ramalina fastigiata |
= |
|
9 |
Cladonia fimbriata |
Trumpet Lichen |
|
10 |
Cladonia coniocraea |
Common Powderhorn |
|
11 |
Cladonia humilis |
= |
|
12 |
Flavoparmelia caperata |
Common Greenshield |
|
13 |
Haematomma ochroleucum |
Bloodstain Lichen |
|
14 |
Caloplaca flavescens |
= |
CONCLUSIONS:
- Revised Index of Ecological Continuity : ancient woodland indicators
- Hawksworth – Rose Scale: air pollution
- Ecology is complicated
- Lichen thallus types
- Looking at fruiting bodies (apothecia), rhizine structure, soredium and spores.
Glossary:
- Apothecium the disc or cup shaped ascoma characteristic of discomycete fungi. The tips of the asci are freely exposed. Most lichens contain discomycete fungi and such lichen fungi also form apothecia.
- Ascoma the fruiting body of all fungi of the Ascomycota.
- Rhizina a tuft or hyphae projecting from the underside of a thallus. It is usually mainly for attachment to the substrate.
- Soredium agent of vegetative reproduction and is seen as powdery dust on the lichen surface.
- Thallus the vegetative body of a lichen.
HH@MBAN
