The lichens of Buda

A survey of lichen growth as an

indication of air pollution

Purpose of the studyTo estimate pollution levels

according to the type and density of lichens found at selected sites in

Budapest

ExpectationsGiven the distance from the city

center, the prevailing wind conditions and the topography, we

expected to find a more robust supply of lichens, as well as ones more sensitive to pollution, at the

more distant sites

Methodology• Sites• Trees• Bioindicator species • Technique and tools

Maple acer

Lichen as bio-indicator

• Symbiotic association of alga and fungi• Plantlike but no roots or leaves • Interior of lichen thallus (body) is exposed to the environment all the time • No structures to isolate internal tissues• No mechanisms to protect from adverse environmental conditions• When air pollution occurs lichen is totally immersed in the toxic atmosphere and the whole organism is at risk

Technique

• Use of quadrates: 4 squares with average

• 1m above ground• Four cardinal

points • Data analysis

Budapest air pollution monitoring stations

Two monitoring stations’ data is needed to control our preconceptions and our results:

• BP4 Pesthidegkút - at Buda Hills (close to Nagyrét and Adyliget)

• BP3 Baross – at Pest (close to the Városliget –CityPark)

Air pollution data measured at BP3 and BP4

As we see the BP3 station measured higher pollution levels almost during the whole year (this is due to the fact that BP3 is at the city center and BP4 is at the suburbs)

Meteorological information about Budapest

Yellow: daily average temperature for recent yearsRed: summer of 2006

Sites chosen

• City Park • Nagyret• Ady Liget

City Park – Downtown Pest• Flat, formerly marshland• Terrain continually rising away from

Danube• Middle of densely populated area• High levels of traffic in all directions• Thermal baths, fun park, zoo, circus• Largest green area of Pest

About Buda

• Buda is the “lungs” of the city

• Hills, valleys, forests and meadows

• Protected natural areas and 300-500m high hills

•Winds from the northwest

Buda sites

• Both sites about 7 km from city center

• No industrial activity in the vicinity• About 100,000 inhabitants in 2nd

district• Main soil types: limestone,

dolomite, marl and sandstone

Ady Liget

• Basin of the “cool valley” (2 deg. colder)• Partly suburbanized (1920s) forestland

Nagyret

• Popular for hiking• Roads and train

Findings

Air pollution!

Few lichens at all in the City Park

Air pollution!

• More lichens in Buda, primarily hypogymnia physodes

• Young, pale specimins• Predominantly on one

side of the trees• Varieties that love

nitrogen

Healthy hypogymnia physodes

© 2004 J.K. Lindsey

Lichen data (1)

Lichen data (2)

Lichen data (3)

Limitations

• Site selection• Sample selection• Methodology• Assessment of surrounding

environment• Absence of control• Representative sample• Time constraint

Conclusion

• Signs of air pollution at all sites

• Greater air pollution in city center

• High levels of nitrogen and phosphorous