Further evidence of the effects of global warming on lichens, particularly those with Trentepohlia phycobionts

Article · April 2007with249 Reads
DOI: 10.1016/j.envpol.2006.03.018 · Source: PubMed
Increasing evidence suggests that lichens are responding to climate change in Western Europe. More epiphytic species appear to be increasing, rather than declining, as a result of global warming. Many terricolous species, in contrast, are declining. Changes to epiphytic floras are markedly more rapid in formerly heavily polluted, generally built-up or open rural areas, as compared to forested regions. Both the distribution (southern) and ecology (warmth-loving) of the newly established or increasing species seem to be determined by global warming. Epiphytic temperate to boreo-montane species appear to be relatively unaffected. Vacant niches caused by other environmental changes are showing the most pronounced effects of global warming. Species most rapidly increasing in forests, although taxonomically unrelated, all contain Trentepohlia as phycobiont in addition to having a southern distribution. This suggests that in this habitat, Trentepohlia algae, rather than the different lichen symbioses, are affected by global warming.
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Further evidence of the effects of global warming on lichens,
particularly those with Trentepohlia phycobionts
A. Aptroot
, C.M. van Herk
ABL Herbarium, G.v.d. Veenstraat 107, NL-3762 XK Soest, The Netherlands
Lichenologisch Onderzoeksbureau Nederland, Goudvink 47, NL-3766 WK Soest, The Netherlands
Received 15 October 2005; accepted 10 March 2006
Epiphytic and terr icolous lichens in Western Europe respond to global warming through their Trentepohlia algae.
Increasing evidence suggests that lichens are responding to climate change in Western Europe. More epiphytic species appear to be increas-
ing, rather than declining, as a result of global warming. Many terricolous species, in contrast, are declining. Changes to epiphytic floras are
markedly more rapid in formerly heavily polluted, generally built-up or open rural areas, as compared to forested regions. Both the distribution
(southern) and ecology (warmth-loving) of the newly established or increasing species seem to be determined by global warming. Epiphytic
temperate to boreo-montane species appear to be relatively unaffected. Vacant niches caused by other environmental changes are showing
the most pronouced effects of global warming. Species most rapidly increasing in forests, although taxonomically unrelated, all contain
Trentepohlia as phycobiont in addition to having a southern distribution. This suggests that in this habitat, Trentepohlia algae, rather than
the different lichen symbioses, are affected by global warming.
Ó 2006 Elsevier Ltd. All rights reserved.
Keywords: Algae; Biomonitoring; Climate change; Europe
1. Introduction
Lichens have certain ecological and physiological require-
ments that make them very sensitive to atmospheric changes
and are thus excellent indicators of air pollution. Lichen mon-
itoring has become a widely used sta ndard to evaluate air qual-
ity and is an effective early-warning system, including the
accumulation of heavy metals and radioactivity in terrestrial
ecosystems (for a review see Nimis et al., 2002). Monitoring
has hitherto focused on air pollution effects, because most
lichens are highly sensitive to SO
(Hawksworth and Rose,
1970; Seaward, 1993). Classic lichen-based monitoring has
generated pollution maps showing areas largely devoid of
epiphytic lichens, the so-called lichen deserts, in and around
cities in, for example, Britain (Hawksworth and Rose, 1970),
Germany (Kirschbaum et al., 1996; Stapper and Kricke,
2004) and the Netherlands (Barkman, 1958).
In some parts of Europe, the use of lichens to monitor
environmental changes has been facilitated by the long-term
attention paid to these organisms, with data extending back
over several decades. For instance, in the Netherlands, detailed
data on the epiphytic lichen flora are available since the 1950s
(Barkman, 1958; de Wit, 1976). In recent decades, air quality
in most of Western Europe has improved as a result of socio-
economic changes and pollution abatement strategies. In par-
ticular, SO
levels have dramatically decreased and as a result,
a recovery of the lichen flora became apparent in the 1980s
(Hawksworth and McManus, 1989; van Dobben and de
Bakker, 1996). Although this recovery is still in progress
(van Herk and Aptroot, 1998), the regenerating lichen flora
differs from the flora that disappeared. Major shifts in commu-
nity structure are nowadays linked to changes in atmospheric
* Corresponding author. Tel.: þ31 35 6027417; fax: þ31 30 2512097.
E-mail addresses: andreaptroot@wanadoo.nl (A. Aptroot), lonsoest@wxs.
nl (C.M. van Herk).
0269-7491/$ - see front matter Ó 2006 Elsevier Ltd. All rights reserved.
Environmental Pollution 146 (2007) 293e298
pollutant levels, especially ammonia (NH
tions have decreased in many areas (van Herk, 1999, 2001 ).
Changes in the epiphytic lichen flora of the Province of
Utrecht in the Netherlands appear significant for all separate
intervals (usually 5 years) of investi gation.
Many lichen species are heavily dependent on climate, of-
ten influenced by minor fluctuations. Climate change has a
profound influence on the distributions of these sensitive
organisms (Watson et al., 2004). A recent study in the Nether-
lands, based on monitoring at five-year intervals since 1979,
has identified recent major changes in epiphyte distribution
independent of pollution. Warm-temperate species have signif-
icantly increased, and species characteristic of cold environ-
ments have either decreased or disappeared (van Herk et al.,
2002). Climate change was statistically found to be the most
probable explanation for these patterns. This study, one of
the first long-term biological monitoring programmes to detect
the influence of global warming on terrestrial communities,
strongly suggests that this phenomenon has affected lichen
populations. Duly cited and used by Parmesan and Yohe
(2003) in their recent impressive meta-study, it is the only
such lichenological data set. The conclusion can thus be drawn
that lichens are among the most sensitive organisms respond-
ing to global warming. Some base-line studies have recently
been set up to specifically target the effects of climate change
on lichens (Insarov and Schroeter, 2002; Aptroot and van
Herk, 2003). This paper reports further evidence of lichen re-
sponses attributable to global warming and highlights the sig-
nificance of Trentepohlia phycobionts.
2. Data and methods
Fieldwork was carried out by the authors in four regions within the Nether-
lands, viz. the provinces of Utrecht in 1979, 1984, 1989, 1995 and 2001 (van
Herk, 2002), Zeeland in 1997, 2000 and 2003 (van Herk, 2004a), Gelderland
in 1990 and 2002 (van Herk, 2004b), and the Noordhollands Duinreservaat in
1990, 1993 and 2000 (Sparrius and Aptroot, 2001), the latter being a forested
coastal dune area NW of Amsterdam. Each monitoring site usually consisted
of ten trees of the same species, for which all lichen species were recorded per
individual tree. This method allows monitoring of species’ abundances both at
separate sites and at study areas as a whole. At each of the four study areas,
250e1500 localities are involved.
For each species, the latitudinal distribution was derived from a wide range
of lichen checklists and floras, e.g. Purvis et al. (1992) and Wirth (1995). Four
categories were distinguished:
1. predominantly pan-tropical species, often extending into (warm-) temper-
ate areas;
2. species with a warm-temperate to (sub)tropical distribution, i.e. with the
majority of the distribution well south of the Netherlands;
3. predominantly (or only) cool-temperate, often very widespread over all
vegetation zones in at least the northern hemisphere;
4. boreo-montane/arctic-alpine species, the majority distributed far north of
the Netherlands or at altitudes well above sea level, mainly in the mon-
tane and/or alpine belt.
Temperature preferences were taken from Wirth (1991) where listed. Other
species (including many new arrivals) were excluded from this analysis.
Wirth’s temperature classes 3, 4, 5, 6, 7 and 8/9 have been translated and
abbreviated into the terms ‘cold’, ‘cool’, ‘average’, ‘rather warm’, ‘warm’
and ‘very warm’, respectively.
3. Results and discussion
3.1. Epiphytic lichens on free-standing trees respond to
global warming
Most of the observed changes are very similar in all four
study areas. For example, many lichens that are increasing
in frequency are warm-temperate or subtropical. One example
is Flavoparmelia soredians, a drought-resistant, warm-temperate
species which until recently had its northernmost limit in
southern England (Seaward and Coppins, 2004). It was very
rare in the Netherlands before 1900 (only known from one
record), absent during 1900e1987, and recently became com-
mon throughout the country (van Herk and Aptroot, 1996,
2004) as well as in adjacent countries. A similar ecology
and a comparable rapid increase were observed for Punctelia
borreri (Spier and van Herk, 1997). Both species now occur
throughout the country, although not in equal abundance.
Some species, such as Lecanora confusa are clearly expand-
ing, but they are still largely confined to the relatively warm
and wet southwestern part of the country, mainly the province
of Zeeland. This species was known from only one record be-
fore 1950 and was absent during the period 1950e1990. Some
species are currently increasing that were never previously
reported from the Netherlands, e.g. Physcia tribacioides and
Heterodermia obscurata (Wolfskeel and van Herk, 2000).
Newly established lichens include many species which were
previously unknown to science.
Several epiphytic species new to science have been de-
scribed recently from the Netherlands, viz. Protoparmelia
hypotremella (Aptroot et al., 1997), Fellhanera viridisorediata
(Aptroot et al., 1998), Lecanora barkmaniana (Aptroot and
van Herk, 1999a), Bacidia neosquamulosa (Aptroot and van
Herk, 1999b), Lecanora compallens and L. sinuosa (van
Herk and Aptroot, 1999), Fellhanera ochracea (Sparrius and
Aptroot, 2000) and Bacidia adastra (Sparrius and Aptroot,
2003). These are unlikely to have been previously overlooked,
as most are now common, and tree bark has been int ensively
studied for lichens since the 1950s (Barkman, 1958; de Wit,
1976). Most of these species are currently invading various
countries in Western Europe, but their origin is unclear.
Lecanora barkmaniana was found to be common and abun-
dantly fertile in warm valleys in the Alps (Aptroot et al.,
2001), after it had been described as new to science in 1999
on the basis of many sterile and only two fertile populations
in the Netherlands. Several of the newly described species,
especially Fellhanera viridisorediata, which is described in a
predominantly tropical genus of mostly foliicolous taxa, with
up to 1998 only one extra-tropical species, have close relatives
in warm-temperate to wide-tropical regions (Lu
cking et al.,
1994). Some of the new species may turn out to actually occur
in these areas.
About 10% of the more-or-less common epiphytic species
have recently decreased. Most are acidophytes with a boreo-
montane centre of distribution. For example, Tuckermannopsis
chlorophylla was so common in the 19th century that it had
a Dutch vernacular name. According to very recent fieldwork
294 A. Aptroot, C.M. van Herk / Environmental Pollution 146 (2007) 293e298
in the province of Drenthe, it continues to rapidly decline in
abundance. In this relatively cool northeastern part of the
country, the presently estimated population size on wayside
trees is only some 10% of that found in 1996. The same holds
for Platismatia glauca, which is now rapidly disappearing
from forest trees. Some of the change of these species in the
Netherlands over the last decades can definitely also be attrib-
uted to the high NH
levels. However, recently (after 1997)
levels decreased, as have nitrophytes (van Herk,
2004a,b), but species like T. chlorophylla and P. glauca con-
tinue to become increasingly rare. Global warming is the
most probable explanation for this.
Of all epiphytic and terricolous lichen species in the Neth-
erlands, many more have increased rather than decreased in
abundance (137 versus 79 since 1980; 113 remained the
same), and it appears that the country is regaining its original
lichen flora, which was largely lost due to heavy air pollut ion.
However, a close examination of the changes in lichen com-
munities reveals distinct trends from the expected patterns
in response to eutrophication (NH
) and decreasing SO
concentrations alon e e.g. some pan-tropical epiphytes (e.g.
Anisomeridium polypori, Fellhanera species, P. borreri and
F. soredians) are among the fastest spreading species. For
example, the following species expanded rapidly (>5%, abso-
lute) and increasingly during the period 1995e 2001 in the
province of Utrecht (van Herk et al., 2002): Candelaria con-
color (þ24.7%), Hyperphyscia adglutinata (þ18.9%), Lecanora
barkmaniana (þ16.0%), Parmotrema chinense (þ11.8%),
Physconia grisea (þ11.8%), Lecidella scabra (þ11.6%),
Micarea micrococca (þ11.1%), B. neosquamulosa (þ10.0%),
Diploicia canescens (þ9.6%), Candelariella xanthostigma
(þ7.8%), F. viridisorediata (þ6.8%), and P. borreri (þ6.0%).
Most are warm-temperate and some are even frequent in tropi-
cal regions. Trees in parks in tropical cities (e.g. Cape Town,
Quito, Singapore, Hong Kong) are often covered with assem-
blages dominated by C. concolor and Hyperphyscia adglutinata.
Three of these species were only recently described (Aptroot
et al., 1998; Aptroot and van Herk, 1999a,b). Fewer species
decreased over the same period. These were often acidophytes,
including several boreo-montane ones. The following species
rapidly decreased: Lecanora conizaeoides (68.3%), Hypogym-
nia physodes (26.8%), Evernia prunastri (17.1%), and Plat-
ismatia glauca (7.1%).
Recorded changes in the species composition at epiphytic
monitoring sites over the last decade are shown in Fig. 1.As
can be seen from the graphs, changes in the various provinces
are comparable. In all cases, species with a warm-temperate to
tropical distribution, as well as warmth-loving species (those
with a high temperature preference value) have dramatically
increased. Cold-loving species have usually declined, but not
at the same rate as the increase in warmth-loving species. So
far, the total numbers of boreo-montane species have remained
approximately the same, despite the decline of T. chlorophylla.
Boreo-montane species have, however, always been rare in
Zeeland, in the southwestern part of the country. The graphs
suggest that global warming mainly determines from where
(southern) or what ecology (warmth-loving) the newly
established species are derived. The existing epiphytic temper-
ate to boreo-montane species (with a few exceptions) appear
not to be seriously affected, but are at the same time un able
to increas e, e.g. by occupying vacant niches. This phenome-
non might explain why the effects of global warming have
so far not been observed in natural or more-or-less stable epi-
phytic lichen communities. At least some vacant niches caused
by other environmental changes are probably required to con-
firm the influence of global warming.
3.2. Terricolous lichens respond to global warming
Drift-sand areas at terminal moraines dating from the pen-
ultimate glaciation form a unique habitat for terricolous
lichens at sea level. Vegetation here is usually dominated by
Cladonia species and has a typically boreo-alpine character.
Monitoring of these species-rich areas in the Netherlands
(Sparrius et al., 2001) has shown that these are very stable
communities, with changes in species composition occur ring
only very slowly and probably not being attributable to com-
petition. In general, the age of exposure determines the species
Nevertheless, several species are currently disappearing
from otherwise stable and well-developed drift-sand commu-
nities. No change in management is apparent, and the pattern
of the species loss is not correlated with any pattern of air pol-
lution. The single factor shared by these taxa is that they all
have a predominantly boreo-alpine distribution. Some species,
such as Cladonia rangiferina, and C. sulphurina, most proba-
bly became extinct only recently in the Netherlands. Others,
like Cetraria islandica, which was formerly rather common,
were until recently known from a dozen localities, and now
only have a few remaining populations. Another shift is shown
by Cladonia squamosa, formerly a common species in drift-
sand vegetations until ca. 1980, but disappeared completely
from that habitat and currently only grows on dead wood.
This is an unstable habitat from which it has to constantly
3.3. Global warming effects in forests
Effects of air pollution on lichens have been up to now pre-
dominantly recorded from relatively open environments, espe-
cially from wayside trees or drift-sand areas. The same holds
true for the observed effects of global warming. Although
many lichens occur in closed habitats, especially forests, their
response to global warm ing is less pronounced. Most of the
rapidly increasing species mentioned above are absent or un-
common in forests, with the exception of Micarea micrococca
and B. neosquamulosa. However, the re-investigation in 2000
of the epip hytic lichen flora in the Noordhollands Duinreser-
vaat determined marked changes between 199 0 and 2000
(Table 1). Some newly described species, including Fellhanera
ochracea and F. viridisorediata, were found, but only
infrequently. The three species most dramatically expanding
(more than 4 times) all have a southern distribution, and also
share another character, namely they all contain the alga
295A. Aptroot, C.M. van Herk / Environmental Pollution 146 (2007) 293e298
Trentepohlia as photobiont. In fact, all lichens containing
Trentepohlia occurring in the area have increased in abun-
dance. Increases in lichen abundance can be attributed to a rel-
atively few species containing Trentepohlia. This suggests
global warming may have affected Trentepohlia directly rather
than the fungal components. This phenomenon has also been
recently observed in other areas of the Netherlands and in
adjacent Germany (N. Stapper, personal communication).
3.4. Global warming and lichens in adjacent countries
The examples given above were all from the Netherlands,
where because of intensive lichen monitoring considerable
data are available and already evaluated. However, if the
changes are indeed at least in part attributable to global warm-
ing, similar changes are to be expected in other countries. In-
deed, increasingly such changes are being reported, although
not yet at such a large scale. An example is in England, where
changes possibly attributable to global warming have been
reported in the lichen flora of the formerly heavily polluted
regions (Seaward and Coppins, 2004). For instance, in Kew
Gardens in London, where 20 years ago only one epiphytic
lichen (Lecanora conizaeoides) survived, over 40 species can
now be observed, including thermophilous species like
F. soredians and P. borreri, and of the recently described spe-
cies Bacidia adastra, B. neosquamulosa and Lecanora com-
pallens (Aptroot, 2005). In Denmark, the first signs of global
warming effects on lichen distribution have been recently re-
ported (Søchting, 2004). Th e situation in the adjacent parts
of Belgium (van den Broeck and Aptroot, 2003; van den
Broeck et al., 2005) and Germany ( de Bruyn et al., 2005) is,
not surprisingly, also very similar. Chan ges (including the
occurrences of the recently described species) can at least be
observed in a wide lowland belt ranging from England through
1997 2000 2003
cold %
cool %
average %
rather warm %
warm %
very warm %
1979 1984 1989 1995 2001
1990 2002
1997 2000 2003
number of species / sitenumber of species / site
1979 1984 1989 1995 2001
number of species / site
1990 2002
Fig. 1. (A, C, E) Temperature preferences according to Wirth (1991) of epiphytic lichens in the given years at monitoring sites in the provinces of (A) Zeeland, (C)
Utrecht and (E) Gelderland. The total number of species for which a temperature preference is known is given as 100%. The respective number of sites and the
number of species involved per province is for Zeeland: sites ¼ 225, species ¼ 135; Utrecht: sites ¼ 950, species ¼ 178; Gelderland: sites ¼ 715, species ¼ 160. (B,
D, F) Main distribution areas of epiphytic lichens in the given years at monitoring sites in the provinces of (B) Zeeland, (D) Utrecht and (F) Gelderland. The
number is the average number of species at a monitoring site.
296 A. Aptroot, C.M. van Herk / Environmental Pollution 146 (2007) 293e298
to the border between Germany and Poland (Aptroot, in press)
and even further along the Baltic Sea into Estonia (Aptroot
et al., 2005). On the other hand, few, if any, changes in the li-
chen flora attributable to global warming have been noted in
areas that are either more moun tainous (e.g. the Vosges, the
Alps, most of Scandinavia) and/or experienced fewer losses
due to air pollution in the past (e.g. the Eifel, Scotland, Wales).
Similar effects have also been observed on bryophytes in
Germany (Frahm and Klaus, 2001) and elsewhere (Gignac,
Aptroot, A. Some lichens from Greifswald new to Mecklenburg-Vorpommern.
Aktuelle Lichenologische Mitteilungen NF 15, in press.
Aptroot, A., 2005. Lichens and global warming: excerpts of a lecture by Andre
Aptroot at the. AGM. Bulletin of the British Lichen Society 96, 14e17.
Aptroot, A., Brand, A.M., Spier, L.J., 1998. Fellhanera viridisorediata, a new
sorediate species from sheltered trees and shrubs in western Europe.
Lichenologist 30, 21e26.
Aptroot, A., Czarnota, P., Ju
riado, I., Kocourkova
, J., Kukwa, M., Lohmus, P.,
Palice, Z., Randlane, T., Saag, R., Se
rusiaux, E., Sipman, H.J.M.,
Sparrius, L.B., Suija, A., Thu
s, H., 2005. New or interesting lichens and
lichenicolous fungi found during the 5th IAL Symposium in Estonia. Folia
Cryptogamica Estonica 41, 13e22.
Aptroot, A., Diederich, P., van Herk, C.M., Spier, L.J., Wirth, V., 1997. Pro-
toparmelia hypotremella, a new sterile corticolous species from Europe,
and its lichenicolous fungi. Lichenologist 29, 415e424.
Aptroot, A., Sparrius, L.B., van Herk, C.M., de Bruyn, U., 2001. Origin and
distribution of recently described lichens from The Netherlands. Aktuelle
Lichenologische Mitteilungen NF 5, 13e25.
Aptroot, A., van Herk, C.M., 1999a. Lecanora barkmaneana, a new nitrophi-
lous sorediate corticolous lichen from The Netherlands. Lichenologist 31,
Aptroot, A., van Herk, C.M., 1999b. Bacidia neosquamulosa, a new and
rapidly spreading corticolous lichen species from western Europe. Lichen-
ologist 31, 121e127.
Aptroot, A., van Herk, C.M., 2003. Review: lichens and global warming.
International Lichenological Newsletter 35, 57e58.
Barkman, J.J., 1958. Phytosociology and Ecology of Cryptogamic Epiphytes.
Van Gorcum, Assen.
van den Broeck, D., Aptroot, A., 2003. De korstmossen van Pepingen en
omgeving (Vlaams-Brabant, Belgie
): een verkenning. Muscillanea 23,
van den Broeck, D., Aptroot, A., Jordaens, D., Sparrius, L.B., Poeck, J., 2005.
Een lichenologische excursie naar Lille en omgeving (Belgie
, Provincie
Antwerpen). Buxbaumiella 70, 19e22.
de Bruyn, U., Aptroot, A., Sparrius, L.B., Linders, W., 2005. Ergebnisse eines
Flechten-Kartierungstreffens in Ostfriesland (Nordwest-Niedersachsen).
Aktuelle Lichenologische Mitteilungen NF 14, 18e29.
van Dobben, H.F., de Bakker, A.J., 1996. Re-mapping epiphytic lichen biodi-
versity in The Netherlands: effects of decreasing SO
and increasing NH
Acta Botanica Neerlandica 45, 55e71.
Frahm, J.-P., Klaus, D., 2001. Bryophytes as indicators of recent climate fluc-
tuations in Central Europe. Lindbergia 26, 97e104.
Gignac, L.D., 2001. Bryophytes as indicators of climate change. Bryologist
104, 410e420.
Hawksworth, D.L., McManus, P., 1989. Lichen recolonization in London
under conditions of rapidly falling sulphur dioxide levels, and the con-
cept of zone skipping. Botanical Journal of the Linnean Society 100,
Hawksworth, D.L., Rose, F., 1970. Qualitative scale for estimating sulphur di-
oxide air pollution in England and Wales using epiphytic lichens. Nature
227, 145e148.
van Herk, C.M., 1999. Mapping of ammonia pollution with epiphytic lichens
in the Netherlands. Lichenologist 31, 9e20.
van Herk, C.M., 2001. Bark pH and susceptibility to toxic air pollutants as
independent causes of changes in epiphytic lichen composition in space
and time. Lichenologist 33, 419e441.
van Herk, C.M., 2002. Monitoring van epifytische korstmossen in de provincie
Utrecht, 1979e2001. LON, Soest.
van Herk, C.M., 2004a. Monitoring van ammoniak met korstmossen in Zee-
land, 1997e2003. LON, Soest.
van Herk, C.M., 2004b. Korstmossen in Gelderland: milieuindicatie, natuur-
waarde, veranderingen 1990e2002. LON, Soest.
van Herk, C.M., Aptroot, A., 1996. Epifytische korstmossen komen weer
terug. Natura 93, 130e133.
van Herk, C.M., Aptroot, A., 1998. Recovery of epiphytic lichens in the
Netherlands. British Lichen Society Bulletin 82, 22e26.
van Herk, C.M., Aptroot, A., 1999. Lecanora compallens and L. sinuosa, two
new overlooked corticolous lichen species from western Europe. Lichenol-
ogist 31, 543e553.
van Herk, C.M., Aptroot, A., 2004. Veldgids Korstmossen. Uitgeverij KNNV,
van Herk, C.M., Aptroot, A., van Dobben, H.F., 2002. Long-term monitoring
in the Netherlands suggests that lichens respond to global warming.
Lichenologist 34, 141e154.
Insarov, G., Schroeter, B., 2002. Lichen monitoring and climate change. In:
Nimis, P.L., Scheidegger, C., Wolseley, P.A. (Eds.), Monitoring with
Lichens e Monitoring Lichens. Kluwer, Amsterdam, pp. 183e201.
Kirschbaum, U., Marx, A., Schiek, J.E., 1996. Beurteilung der lufthygieni-
schen Situation Gieszens und Wetzlars mittels epiphytischer Flechten.
Journal of Applied Botany 70, 78e96.
cking, R., Lumbsch, H.T., Elix, J.A., 1994. Chemistry, anatomy and mor-
phology of foliicolous species of Fellhanera and Badimia (Lichenized
Ascomycotina: Lecanorales). Botanica Acta 107, 393e401.
Nimis, P.L., Scheidegger, C., Wolseley, P.A. (Eds.), 2002. Monitoring with
Lichens e Monitoring Lichens. Kluwer, Amsterdam.
Parmesan, C., Yohe, G., 2003. A globally coherent fingerprint of climate
change impacts across natural systems. Nature 421, 37e42.
Purvis, O.W., Coppins, B.J., Hawksworth, D.L., James, P.W., Moore, D.M.
(Eds.), 1992. The Lichen Flora of Great Britain and Ireland. Natural
History Museum Publications & The British Lichen Society, London.
Seaward, M.R.D., 1993. Lichens and sulphur dioxide air pollution: field stud-
ies. Environmental Reviews 1, 73e
Seaward, M.R.D., Coppins, B.J., 2004. Lichens and hypertrophication. Biblio-
theca Lichenologica 88, 561e572.
Table 1
Comparison between 1990 and 2000 of identical epiphytic monitoring sites in
the Noordhollands Duinreservaat
1990 2000
Species that increased over 4 times
Anisomeridium polypori 152
Arthonia spadicea 17 83
Gyalideopsis anastomosans 111
Remaining species with Trentepohlia
Arthonia radiata 23
Dimerella pineti 64 95
Enterographa crassa 11
Graphis scripta 34
Opegrapha species 5 17
Porina aenea 16 25
Schismatomma decolorans 35
Total of lichens with Trentepohlia 113 296 þ186
Total of all lichen occurrences 3586 3765 þ189
Listed are the species that increased over four times, and the remaining species
with Trentepohlia as photobiont. The numbers are the number of monitoring
sites with the respective species.
297A. Aptroot, C.M. van Herk / Environmental Pollution 146 (2007) 293e298
Søchting, U., 2004. Flavoparmelia caperata e a probable indicator of
increased temperatures in Denmark. Graphis Scripta 15, 53e56.
Sparrius, L.B., Aptroot, A., 2000. Fellhanera ochracea, a new corticolous
lichen species from sheltered habitats in Western Europe. Lichenologist
32, 515e520.
Sparrius, L.B., Aptroot, A., 2001. Monitoring van epifytische mossen en korst-
mossen in 2000 in het Noord-Hollands Duinreservaat. Adviesbureau voor
Bryologie en Lichenologie, Soest.
Sparrius, L.B., Aptroot, A., 2003. Bacidia adastra, a new sorediate lichen
species from Western Europe. Lichenologist 35, 275e278.
Sparrius, L.B., van Herk, C.M., Aptroot, A., van Dobben, H.F., 2001. Lande-
lijk Meetnet Korstmossen. Inhoudelijke rapportage 1999. Buxbaumiella
56, 1e32.
Spier, L.J., van Herk, C.M., 1997. Recent increase of Parmelia borreri in The
Netherlands. Lichenologist 29, 390e393.
Stapper, N.J., Kricke, R., 2004. Epiphytische Moose und Flechten als
Bioindikatoren von sta
dtischer U
rmung, Standortseutrophierung
und verkehrsbedingten Immissionen. Limprichtia 24, 187e208.
Watson, R.T., Core writing team (Eds.), 2004. Climate Change 2001: Synthe-
sis Report. IPCC, Geneva.
Wirth, V., 1991. Zeigerwerte von Flechten. Scripta Geobotanica 18, 215e237.
Wirth, V., 1995. Die Flechten Baden-Wu
rttembergs. Ulmer, Stuttgart.
de Wit, A., 1976. Epiphytic lichens and air pollution in the Netherlands.
Bibliotheca Lichenologica 5, 1e115.
Wolfskeel, D.W., van Herk, C.M., 2000. Heterodermia obscurata nieuw voor
Nederland. Buxbaumiella 52, 47e50.
298 A. Aptroot, C.M. van Herk / Environmental Pollution 146 (2007) 293e298
    • Modern lichen-based environmental analyses provide low cost, high-resolution spatial tools for modelling and mapping the effects of environmental change, when compared to the traditional networks of pollution or climate monitoring stations, allowing its detection, assessment and monitoring at the ecosystem level (Branquinho et al. 2008;Pinho et al. 2008b). They are powerful ecological indicators of pollution (Giordani, Brunialti & Alleteo 2002;McMurray, Roberts & Geiser 2015) and of macro and microclimate change (Aptroot & Van Herk 2007;Pinho, M aguas & Branquinho 2010;Matos et al. 2015;Root et al. 2015). Lichen-based thresholds were used to establish the lowest critical levels for nitrogen concentration and critical loads for nitrogen deposition in Europe and the USA, contributing to the protection of ecosystem services and functions in both natural and semi-natural ecosystems (Cape et al. 2009;Pardo et al. 2011;Pinho et al. 2012;Root et al. 2015).
    [Show abstract] [Hide abstract] ABSTRACT: • Lichens have been used to efficiently track major drivers of global change from the local to regional scale since the beginning of the industrial revolution (sulphur dioxide) to the present (nitrogen deposition and climate change). Currently, the challenge is to universalize monitoring methodologies to compare global change drivers’ simultaneous and independent effects on ecosystems and to assess the efficacy of mitigation measures. • Because two protocols are now used at a continental scale North America (US) and Europe (EU), it is timely to investigate the compatibility of the interpretation of their outcomes. For the first time, we present an analytical framework to compare the interpretation of data sets coming from these methods utilizing broadly accepted biodiversity metrics, featuring a paired data set from the US Pacific Northwest. • The methodologies yielded highly similar interpretation trends between response metrics: taxonomic diversity, functional diversity and community composition shifts in response to two major drivers of global change (nitrogen deposition and climate). A framework was designed to incorporate surrogates of species richness (the most commonly used empirical trend in taxonomic diversity), shifts in species composition (compositional turnover) and metrics of functional diversity (link between community shifts to effects and ecosystem structure and functioning). These metrics are essential to more thoroughly comprehend biodiversity response to global change. Its inclusion in this framework enables future cross-continental analysis of lichen biodiversity change from North America and Europe in response to global change. Future works should focus on developing independent metrics for response to global change drivers, namely climate and pollution, taking us one step closer to a lichen-based global ecological indicator.
    Full-text · Article · Jan 2017
    • Thus, our study corroborates the hypothesis of environmental sharing of the photobionts in lichens especially in the colder boreal, arctic/alpine and temperate climates where the dry and cold, as well as fluctuating, climate is probably the major selective pressure. Several studies proposed the photobiont as an important functional trait of lichens, relevant for the response of the lichen to the environment, especially to humidity (Aptroot & van Herk, 2007; Marini et al., 2011; Giordani et al., 2012; Matos et al., 2015). Thus, it is tempting to speculate that freeze tolerance in arctic/alpine and temperate environments, and desiccation and high-intensity light tolerance in Mediterranean environments are potentially a few such traits associated with the locally superior and adaptive algal genotypes.
    [Show abstract] [Hide abstract] ABSTRACT: Both macroclimate and evolutionary events may influence symbiont association and diversity patterns. Here we assess how climatic factors and evolutionary events shape fungal–algal association patterns in the widely distributed lichen-forming fungal genus Protoparmelia. Multilocus phylogenies of fungal and algal partners were generated using 174 specimens. Coalescent-based species delimitation analysis suggested that 23 fungal hosts are associating with 20 algal species. Principal component analysis (PCA) was performed to infer how fungal–algal association patterns varied with climate. Fungi associated with one to three algal partners whereas algae accepted one to five fungal partners. Both fungi and algae were more specific, associating with fewer partners, in the warmer climates. Interaction with more than one partner was more frequent in cooler climates for both the partners. Cophylogenetic analyses suggest congruent fungal–algal phylogenies. Host switch was a more common event in warm climates, whereas failure of the photobiont to diverge with its fungal host was more frequent in cooler climates. We conclude that both environmental factors and evolutionary events drive fungal and algal evolution in Protoparmelia. The processes leading to phylogenetic congruence of fungi and algae are different in different macrohabitats in our study system. Hence, closely related species inhabiting diverse habitats may follow different evolutionary pathways.
    Full-text · Article · Dec 2016
    • Climate changes, atmospheric pollution, green areas fragmentation, and other environmental changes may also affect lichen communities, due to the physiological response of each individual. Such changes have been directly influencing lichens over the years, changing their habitats or the interaction of each specimen with other organisms (Insarov & Schroeter 2002, Aptroot & Van Herk 2007, Käffer et al. 2011). In Brazil, few studies relate lichen community structure to host tree structure, and the existing ones are restricted to non-urban areas (Marcelli 1992, Cáceres et al. 2008, Fleig & Grüninger 2008, Käffer et al. 2009, Martins & Marcelli 2011).
    [Show abstract] [Hide abstract] ABSTRACT: We investigated the changes in lichen community structure (vertical distribution and thallus size) in relation to host tree availability for lichen establishment in urban areas. Lichens were mapped on 300 phorophytes distributed in 30 sampling stations in order to verify differences in the vertical distribution of species and thallus size versus host tree characteristics. Significant differences were observed in vertical distribution, considering lichen richness and abundance. This study reported the influence of host trees, especially tree diameter and bark texture, on epiphytic lichen communities in an urban area. RESUMO.– Estrutura da comunidade liquênica versus superfície da casca dos forófitos em ambiente urbano, no sul do Brasil. Neste trabalho, investigamos as modificações na estrutura da comunidade liquênica (distribuição vertical e tamanho de talo liquênico) em relação à disponibilidade de forófitos para o estabelecimento dos liquens na área urbana. Os liquens foram mapeados em 300 forófitos distribuídos em 30 estações de amostragem, a fim de verificar as diferenças na distribuição vertical das espécies e no tamanho do talo dos liquens em relação às características dos forófitos. Diferenças significativas foram observadas quanto à distribuição vertical considerando a riqueza e abundância dos liquens. Este estudo demonstra a influencia dos forófitos, principalmente do diâmetro e da textura da casca sobre a comunidade de liquens epífitos em área urbana. Palavras-chave: corticícolas, distribuição vertical, espécies especialistas
    Full-text · Article · May 2016 · Plant Disease
    • Batı Avrupa'da küresel ısınmaya cevap olarak epifitik likenlerde artış gözlenirken buna karşılık terrikollerde ise azalma kaydedilmiştir. Kirlilliğin etkisindeki bölgelerde ormanlara oranla daha hızlı bir değişimle, Trentepohlia alg bileşenli ve güney yayılışlı liken türlerinde bolca artış rapor edilmiştir [98]. İsviçre'de sıcaklık artışlarının belirginleştiği, SO 2 'in azalmasına karşılık NH 3 'ün arttığı yıllarda (1989199019911992199319941995) yapılan çalışmada [99], liken florasında 22 yılda meydana gelen değişimler incelenmiş ve sub-tropikal türlerde büyük yükseliş olurken (%83), arktik-alpin/boreal türlerde ise %50 oranda düşüş görüldüğü tespit edilmiştir.
    Article · Dec 2015 · Plant Disease
    • Lichens can be saxicolous, i.e. growing on rocks, terricolous, i.e. on soil, muscicolous or hepaticolous on bryophytes, foliicolous on the surface of living leaves, and corticolous on the bark of trees, which is the majority of epiphytic species. Substrate features and abiotic factors have been shown to influence the distribution and occurrence of lichen species (Purvis 2000; Aptroot & Herk 2007; Dyer & Letourneau 2007; Käffer et al. 2007; Bunnell et al. 2008; Mezaka et al. 2008; Morales et al. 2009). Ecological studies on lichens in northeastern Brazil have been undertaken, first with foliicolous (Cáceres et al. 2000), and then corticolous microlichens (Cáceres et al. 2007; 2008a; b; Cavalcante 2012; Rodrigues 2012).
    [Show abstract] [Hide abstract] ABSTRACT: The present study tested the hypothesis that species richness and composition of epiphytic microlichens can be used to support the phytosociological differentiation between Caatinga and Brejos de Altitude, as exemplified by the Muralha Reserve (Caatinga) and the Parque Estadual Mata do Pau Ferro (Brejo de Altitude), in the state of Paraíba, Brazil. A total of 755 lichen samples were collected, comprising 18 families, 42 genera and 111 species of epiphytic, corticolous microlichens. Overall species richness was higher in the Caatinga, with 67 species, compared to the Brejo, with 46 species. Species richness per sample was significantly higher in the Caatinga compared to the Brejo. Taxonomic composition also differed significantly between the two areas, with Arthoniaceae, Caliciaceae, Chrysothrichaceae, Graphidaceae (particularly Graphis), Lecanoraceae, Mycoporaceae, Pertusariaceae, and Trypetheliaceae being dominant in, or exclusive to, the Caatinga, whereas Coenogoniaceae, Graphidaceae (Diorygma, Fissurina, Myriotrema, Ocellularia, Phaeographis, Sarcographa), Malmideaceae, Porinaceae and Strigulaceae were dominant in, or exclusive to, the Brejo. Five new species were discovered as result of this study. This is the first study to quantitatively compare richness and community patterns of epiphytic microlichens between two major biomes in Northeastern Brazil, and the first detailed lichen study in the state of Paraíba.
    Full-text · Article · Dec 2015
    • It has recently been documented that global warming has influenced the migration of trentepohlialean algae and the tropical lichens that associate with them. A study conducted by Aptroot and vanHerk (2007)noted that a majority of the epiphytic lichens rapidly colonizing forests in Western Europe are associated with the Trentepohliales. Temperature and disease distribution.
    [Show abstract] [Hide abstract] ABSTRACT: Most plant pathologists know certain algae can be used as gelling agents in culture media. Pathologists practicing in tropical or subtropical environments also know that some algae damage plants. The five genera in the order Trentepohliales (Chlorophyta) are unique and fascinating. Among other characteristics they are subaerial, bright orange to red in color and one genus, Cephaleuros, is a plant pathogen while another, Stomatochroon, is a space parasite. Cephaleuros causes algal spot and includes 17 accepted species. Of these, 13 develop between the cuticle and the epidermis of their hosts and 4 grow intercellularly. The latter are especially damaging, causing chlorosis and branch dieback. Zoospores and gametes germinate on plant surfaces during the rainy season and probably penetrate through breaks in the host cuticle. Their filamentous growth forms thalli that produce sporangiophores and spherical gametangia the following year. Several species of Cephaleuros have a broad host range and though their damage is usually superficial it can be economically important on certain crops. Plant stress is the greatest predisposing factor to this algal disease. Management includes providing plants with sufficient moisture and nutrients, modifying cultural and harvesting practices, and planting resistant cultivars when available.
    Full-text · Article · Mar 2015
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