title: Accumulation of trace elements in the peripheral and central parts of two species of epiphytic lichens transplanted to a polluted site in Portugal.
abstract: This paper compares the dynamics, i.e. the rates of change in element concentrations of young and older lichen thallus parts, of one foliose and one fruticose lichen, during a transplant experiment to a polluted site. Both lichen parts respond to environmental changes. Here, differential accumulation suggests that differential constitution leads to differential uptake and release, and/or the overall behaviour is partly due to internal translocation and regulation mechanisms within the whole lichen. For thallus parts, internal translocation should be taken into account as one more factor affecting lichen "memory length". Young parts of the thallus presented higher rates of change, but different lichen parts accumulate different elements to different extents. Therefore tissue selection in monitoring may depend on the element of interest, and cannot be made into a generalized approach in survey set-ups: the choice depends on the element.
authors.affiliation: Instituto Tecnológico e Nuclear Reactor, Apartado 21, E.N. 10, 2686-953 Sacavém, Portugal. rveloso@itn.pt
authors.forename: R M
authors.initials: RM
authors.lastname: Godinho
authors.forename: T G
authors.initials: TG
authors.lastname: Verburg
authors.forename: M C
authors.initials: MC
authors.lastname: Freitas
authors.forename: H Th
authors.initials: HT
authors.lastname: Wolterbeek
mesh_terms: D000393:Air Pollutants / Q000032:analysis* / Q000378:metabolism; D004784:Environmental Monitoring / Q000379:methods*; D008011:Lichens / Q000737:chemistry* / Q000378:metabolism; D011174:Portugal; D014131:Trace Elements / Q000032:analysis* / Q000378:metabolism
chemical_list: D000393:Air Pollutants; D014131:Trace Elements