The lichens of Buda A survey of lichen growth as an indication of air pollution

Purpose of the study To estimate pollution levels according to the type and density of lichens found at selected sites in Budapest

Expectations Given 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 years Red: 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 m 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 2 nd 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