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Long-term monitoring in the Netherlands suggests that lichens respond to global warming

Authors:
  • Laboratório de Botânica/Liquenologia

Abstract and Figures

There is evidence to suggest that part of the recent changes in the lichen flora of the Netherlands is attributable to an increase in temperature. Changes which have occurred over the last 22 years were studied in detail, and were subjected to a statistical treatment by comparing the change of species to their latitudinal distribution and to ecological determinants.All 329 epiphytic and terrestrial lichen species occurring in the Netherlands were considered in relation to their world distribution. Arctic-alpine/boreo-montane species appear to be declining, while (sub)tropical species are invading. The proportion of increasing species is by far the largest among the wide-tropical lichens (83%), and smallest among the arctic-alpine/boreo-montane lichens (14%). None of the wide-tropical species was found to decrease, while 50% of the arctic-alpine/boreomontane species show a decline. Long-term monitoring of the epiphytic lichen flora in the province of Utrecht from 1979 onwards shows that the total number of taxa present increased from 95 in 1979 to 172 in 2001, while the average number of taxa per site increased from 7·5 to 18·9. The rate of increase was greatest by far between 1989 and 1995. The majority of the species (152 taxa or 85%) show a gross increase, only 17 species (10%) show a decrease. A detailed analysis of these data using multiple regression suggests global warming as an additional cause for recent changes, next to decreasing SO2 and increasing NH3. Changes appear to be correlated initially (1979-1995) only with toxitolerance and nutrient demand. Changes between 1995 and 2001, however, appear positively correlated to both temperature and nutrient demand, indicating a recent and significant shift towards species preferring warm circumstances, independent from, and concurrent with changes due to nutrient availability.This is the first paper reporting long-term floristic changes for lichens that appear to be correlated significantly with increasing temperatures. We suggest that future lichen monitoring programmes also pay attention to effects of climatic change, instead of focusing on air pollution effects only.
Content may be subject to copyright.
Lichenologist
34(2): 141-154 (2002)
doi:
10.1006/lich.2002.0378, available online at http://www.idealibrary.com on IDEM1
Long-term monitoring
in
the
Netherlands suggests that lichens
respond
to
global warming
C.
M. van HERK,
A.
APTROOT and H.
F.
van DOBBEN
Abstract: There
is
evidence
to
suggest that part
of
the recent changes
in
the
lichen flora
of
the
Netherlands
is
attributable
to an
increase
in
temperature. Changes which have occurred over
the last
22
years were studied
in
detail,
and
were subjected
to
a
statistical treatment
by
comparing
the change
of
species
to
their latitudinal distribution
and to
ecological determinants.
All
329
epiphytic
and
terrestrial lichen species occurring
in
the
Netherlands were considered
in
relation to their world distribution. Arctic-alpine/boreo-montane species appear to be declining, while
(sub)tropical species
are
invading.
The
proportion
of
increasing species
is by far the
largest among
the wide-tropical lichens (83%), and smallest among the arctic-alpine/boreo-montane lichens (14%).
None
of
the
wide-tropical species
was
found
to
decrease, while
50%
of
the
arctic-alpine/boreo-
montane species show
a
decline.
Long-term monitoring of the epiphytic lichen flora
in
the province of Utrecht from 1979 onwards
shows that
the
total number
of
taxa present increased from
95
in
1979
to
172
in
2001, while
the
average number
of
taxa
per
site increased from
7-5
to
18-9. The rate
of
increase was greatest
by far
between 1989
and
1995. The majority
of
the species (152 taxa
or
85%) show
a
gross increase, only
17 species (10%) show
a
decrease.
A
detailed analysis of
these
data using multiple regression suggests global warming as an additional
cause
for
recent changes, next
to
decreasing
SO2
and
increasing
NH3.
Changes appear
to be
correlated initially (1979-1995) only with toxitolerance
and
nutrient demand. Changes between
1995
and
2001, however, appear positively correlated
to
both temperature
and
nutrient demand,
indicating a recent and significant shift towards species preferring warm circumstances, independent
from,
and
concurrent with changes
due to
nutrient availability.
This is the first paper reporting long-term floristic changes
for
lichens that appear to
be
correlated
significantly with increasing temperatures. We suggest that future lichen monitoring programmes also
pay attention
to
effects
of
climatic change, instead
of
focusing
on air
pollution effects only.
'Q
2002 The British Lichen Society Published by Elsevier Science Ltd. All
rights
reserved.
Introduction because most lichens are highly sensitive to
SO2
(Hawksworth & Rose 1970; Seaward
Since the 1950s lichens have been mom- 1993)
Classk
lichen-based monitoring has
tored in many countries to assess environ-
generated
pollution maps showing areas
mental changes. Monitoring has hitherto j ly
devoid
of
epiphytic lichenS5
^
focused strongly on air pollution effects,
so_called lichen deserts^
in and
around dties
in, for example, Great Britain (Hawksworth
_
, , , T- , , ~ J & Rose 1970), Germany (Kirschbaum et al.
C.
M. van
Herk: Lichenologisch Onderzoekbureau
,
.-..-.^N
i i -K.T i i i •T-. I
Nederland, Goudvink
47,
NL-3766
WK
Soest,
The 1996) and ^
Netherlands (Barkman
Netherlands. 1958). Lichens have even been shown
to
A. Aptroot: Centraalbureau voor Schimmelcultures,
be
useful
as
indicators
for
human health
P.O.
Box
85167, NL-3508
AD
Utrecht,
The
(Cislaghi
&
Nimis
1997)
et eran
s.
,„,,.
, In
recent decades,
air
quality
in
most
of
H.
F. van
Dobben: Alterra Green World Research,
' M f
P.O.
Box 23,
NL-6700
AA
Wageningen,
The
Western Europe
has
improved
as a
result
Netherlands.
of
socio-economic changes
and
pollution
0024-2829/02/020141
+
14 S35.00/0
C
2002
The
British Lichen Society Published
by
Elsevier Science
Ltd. All
rights reserved.
142THE LICHENOLOGISTVol. 34
abatement strategies; in particular SO2 levels
have dramatically decreased. As a result, a
recovery of
the
lichen flora became apparent
in the 1980s (Hawksworth & McManus
1989;
van Dobben & de Bakker 1996).
Although this recovery is still in progress
(van Herk & Aptroot 1998), the regenerat-
ing lichen flora appears to be different from
the pre-industrial flora. A comparison with
the former situation shows a number of
characteristic trends:
1.
Many nitrophilous species are now
extremely common and spreading to
substrata where they were previously
absent (e.g. tree species with endo-
genously acid bark). An apparent ex-
planation lies in the high levels of
atmospheric NH3 currently found in
north-western Europe, as a result of
intensive cattle husbandry (van
Breemen et
al.
1982; van Dobben & de
Bakker 1996; van Herk 1999, 2001a).
The nitrophilous lichens include
many species with predominantly
warm-temperate distributions.
2.
Many acidophilous species are now
decreasing in abundance. This is
especially true for Lecanora conizaeoides,
the sole species that was shown to be
favoured by SO2 (Bates et al. 1996).
However, similar patterns are seen in a
wide range of acidophilous but toxi-
phobous species. This category includes
many boreo-alpine elements.
3.
Most lichens that are increasing in
frequency are warm-temperate or
subtropical elements; an example is
Parmelia soredians, which is a drought-
resistant, warm temperate species
which until recently had its northern-
most limit in southern Scotland. It was
very rare in the Netherlands before
1950,
absent in 1950-1987, and
recently became common all over the
country (van Herk & Aptroot 1996) as
well as in adjacent countries. A similar
ecology and a comparable rapid
increase holds for
P.
borreri
(Spier
&
van
Herk 1997). Similar changes have been
observed in the distribution of some
bryophytes in Central Europe (Frahm
& Klaus 2001).
4.
The newly established lichens include
species with a mainly tropical distri-
bution which are usually recorded as
single specimens, for example
Physcia
tribacioides and Heterodermia obscurata
(Wolfskeel & van Herk 2000). The
latter, originally described from
Colombia, has a pantropical distri-
bution, extending into the subtropics
and reaching northwards to southern
Europe. This phenomenon was not
seen in surveys prior to 1995.
5.
Newly established lichens also include
species which were previously un-
known. Seven epiphytic species new to
science have been described recently
from the Netherlands (Aptroot et al.
1997,
1998; Aptroot & van Herk
1999a, b; van Herk & Aptroot 1999;
Sparrius
&
Aptroot 2000). It is improb-
able that they have been overlooked in
the past, as most of them are common
now, and tree bark has been intensively
studied for lichens since the 1950s
(Barkman 1958; de Wit 1976). At
present, these species, which are still
spreading rapidly, are known only from
Western Europe and their origin is
unclear. However, several of them have
close relatives in warm-temperate to,
wide-tropical regions (Lucking et al.
1994),
and some of the new species may
occur there.
In this paper we provide evidence to
support the hypothesis that climatic
change could be an additional factor for the
observed changes in the distribution pattern
of lichens, besides increasing NH3 and
decreasing SO2. In the Netherlands the
annual average temperature has increased by
0-3°C since 1980 (Houghton et al. 1996),
while the mean precipitation increased from
c. 700 mm year
~ 1
to
c.
800 mm year
~
' over
the past 100 years. According to the most
recent reports from the Dutch meteorologi-
cal institute, K.N.M.I., the annual average
temperatures in the Netherlands were
c. 0-8°C higher during 1991-2000 compared
2002Lichens respond to global warming—van Herk et al.143
to 1961-1990. During recent years, many
temperature records were set in the Nether-
lands,
for example, the mean temperature
for October 2001 was the warmest since
regular measurements began in 1706.
Materials and Methods
Three different analyses were carried out to test the
hypothesis that lichen populations have changed
in response to climate change. First, the estimated
increase or decrease in lichen species in the Netherlands
was compared to the latitudinal distribution patterns of
these species. Second, these changes were related
to seven major determinants of species' ecology
as delineated by Wirth (1991), the so-called 'Ellenberg-
values', using multiple regression. Third, changes in
epiphytic lichen composition that have occurred since
1979 in the central part of the Netherlands were
quantified and analysed, and related again by means of
multiple regression to Wirth's determinants.
The latitudinal distribution of species was derived
from a wide range of lichen checklists and floras, for
example Purvis et al. (1992) and Wirth (1995). Five
categories were distinguished:
1.
predominantly wide-tropical species, often
extending into (warm-) temperate 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 species,
often very widespread over
all
vegetation zones in at
least the northern hemisphere;
4.
boreo-montane/arctic-alpine species, the majority
of
the
distribution well north of the Netherlands or
at altitudes well above sea level, mainly in the
montane and/or alpine belt;
5.
species for which insufficient distribution data are
available (these usually rare species are excluded
from the calculations).
Estimates of the change in the occurrence in the
Netherlands of epiphytic and terricolous lichen species
were obtained by assigning them to six change classes,
ranging from 'strong decrease' to 'very strong increase'
(see below). All six classes relate the present (2000)
occurrence of species with their occurrence in the
1980s. Change class values were derived from checklists
(Brand et
al.
1988; Aptroot et
al.
1999), field meetings
organized by the Dutch Lichenological Society
(BLWG), herbarium material, and long-term monitor-
ing data. Reports of most of the field meetings, com-
plete with species lists per site, are recorded in the
journal Buxbaumiella (1973 onwards). Herbarium
material in all institutional and private herbaria has
been consulted, as well as all data from mapping and
long-term monitoring programmes (de Wit 1976; van
Dobben
&
de Bakker 1996; van Herk
&
Aptroot 1998;
van Herk 1999, 2001a). The predominantly saxicolous
species were not considered, as data about these are
generally too incomplete.
Six change classes were distinguished, defined as
follows:
1.
A species was considered to have a 'strong
decrease' when it had disappeared from more than
50%
of its known stations, while the remaining
populations had diminished as well.
2.
A species was considered to show a 'slight decrease'
when it had disappeared from
20
to
50%
of its stations;
the remaining populations usually became smaller.
3.
'No change' is used when only small changes
( - 20% to +25%) in the numbers of stations were
found; often the sizes of the populations remained
about the same.
4.
Species were considered to have had a 'slight
increase' when they had established at 25 to 100%
new stations; the sizes of the populations often
became larger.
5.
A 'strong increase' was used for species which
occurred at 100 to 500% new stations; the size of
the original populations often became considerably
larger.
6. A 'very strong increase' is valid for species which
had increased more than 500%, often with large
new populations.
If a very rare species became extinct, the change was
counted as a 'slight decrease'. Alternatively, if
a
species
was newly established, it was not automatically counted
as showing a 'very strong increase', but was rated
according to the abundance of the new species, for
example, where a new species was very rare, it was
counted as showing only a 'slight increase', although the
increase was technically over 500%.
A detailed analysis was carried out of the changes in
epiphytic lichen composition that have occurred since
1979 in the province of Utrecht in the central part of
the Netherlands. This area of c. 1500 km2 has been
monitored intensively since the 1970s and a database
with c. 70 000 lichen records was available to analyse
the changes in the occurrences of species. In contrast
to the previous change class estimates, all changes
presented are based on 'hard' field observations at
stations that were revisited in subsequent periods. Data
collected during lichen surveys in 1979 (van der Knaap
1980),
1984 (van der Knaap 1984; fieldwork partly
carried out by A. Aptroot), 1989 (Aptroot 1990), 1995
(van Herk 1996) and 2001 (van Herk 20016) were
used, all based on monitoring sites with usually 10 trees
of the same species. For all species recorded, their
frequency (based on absence/presence per site) was
calculated for the five survey periods from 1979 on-
wards. Changes were derived in a stepwise manner for
5 or 6 year intervals by calculating the increase or
decrease in frequency at sites monitored in both periods
only. Frequencies of species in 1995 (the most extensive
survey) were taken as the starting-point, and fre-
quencies in 2001, 1989, 1984 and 1979 were related to
that period by calculating the frequency for the whole
set based on the differences at the sites which were
monitored during the two survey periods concerned. In
144THE LICHENOLOGISTVol. 34
TABLE
1. Relationship
between increase
or
decrease
of lichen
species
in the Netherlands
since
1980 and the latitudinal
world
distribution of
these species
Change class
2 strong decrease
1
slight decrease
0 no change
+1 slight increase
+ 2 strong increase
+ 3 very strong increase
Total
1
wide-
tropical
0
0
2
5
2
3
12
Latitudinal
2
warm-temperate/
subtropical
3
33
56
57
22
4
175
world distribution
3
cool-
temperate
2
8
31
27
7
1
76
4
boreo-montane/
arctic-alpine
7
26
24
9
0
0
66
Total
12
67
113
98
31
8
329
The values in the body of the table are the numbers of
species
concerned. The numbers in the column and row
headings are class numbers used in the correlation analysis.
this way, all changes due to termination of sites (e.g.
tree felling, etc.), new sites or changed scope of the
survey could be excluded. More than 20 tree species
were involved, mainly Quercus robur,
Populus
x
canadensis, Salix alba, Fraxinus excelsior, Ulntus spp.,
Tilia spp., Fagus sylvatica, Betula spp. and Pinus
sylvestris.
Wirth's seven major ecological determinants of
species are estimates of the species' responses to 'light
demand', 'temperature preference', 'continentaliry',
'moisture-dependence', 'pH preference', 'nutrient
demand' and 'toxitolerance', scored on a nine-point
scale
(1
= preferring deep shade, very cool, hyper-
oceanic, very dry, very acid, nutrient-poor, and clean
circumstances, respectively). In the fitted models
changes were regressed on the seven determinants
following
C
= a+Xi=1
7{$p^),
with a = constant
(intercept), Pj=regression coefficient for determinant i,
D;=value of determinant i, and C=change class
(Table 2) or changes during 1979-1989, 1989-1995
and 1995-2001 in Utrecht (Table 4). The models
presented were derived by stepwise exclusion of non-
significant terms from the full model, i.e. the model
including all seven determinants. For some species
Wirth does not give values for all seven ecological
determinants. All regression models were constructed
using the maximum number of
species
possible for that
combination of predictors.
Results
Estimated change related to latitudinal
distribution
In total, 329 species were used to
relate their change in the Netherlands
since 1980 to their latitudinal world
distribution (Table 1). Many more species
have increased (42%) than decreased
(24%),
while some 34% of the species
remained approximately constant. Many of
the species (57%) have a southern, warm-
temperate to tropical distribution, fewer
(20%) have a boreo-montane and/or arctic-
alpine distribution and 23% are typically
cool-temperate. The relative proportion of
species which have increased appears to be
greatest among the wide-tropical lichens
(83%),
and least among the arctic-alpine/
boreo-montane lichens (14%). The opposite
>
holds for the species which have decreased;
none of the wide-tropical species was
found to have decreased, while 50% of
the arctic-alpine/boreo-montane category
showed a decrease. Thus, arctic-alpine/
boreo-montane species are declining,
while (sub) tropical species are invading the
Netherlands. Warm- and cool-temperate
species are increasing as well (both
c.
46%).
The correlation of the change class number
with the distribution class number per
species (as given in Table 1) is statistically
highly significant (r= - 0-345, w
=
329,
P<0-0001).
Three wide-tropical species, viz.
Anisome-
ridium polypori, Hyperphyscia adglutinata and
Parmelia perlata show a 'very strong
increase'. A 'strong increase' in this
category holds true for Candelaria concolor
2002Lichens respond
to
global warming—van Herk
et al.
145
TABLE
2.
Regression coefficients
and
significance resulting from multiple
regression
of the
change
class
per
species
on
Wirth's (1991)
ecological
determinants
TermRegression
coefficientt-valueP-value
Constant
Light demand
Temperature
Nutrient demand
-0-51
-0-13
+ 0-18
+ 0-21
-
1-16
-2-73
+ 2-50
+ 3-56
0-25
0-0072
0-0135
0-0005
Number of species considered (n) = 146 (34 species with missing values excluded),
degrees of freedom
=
142, explained variance=
18-3%.
Not significant (r and P values
refer to t values of terms excluded from the model): continentality (r= +0-05, P=0-55,
«=127),
moisture dependence (r=-0-ll, P=0-22, n=127), pH-preference
0= -0-12, P=0-17,
«
=
127), toxitolerance (r=
-0-08,
P=0-42, n=103).
and
Fellhanera
bouteillei.
Warm-temperate
species showing
a
'very strong increase'
are
Candelariella reflexa, Lecidella flavosorediata,
Parmelia
borreri
and P.
soredians.
The
boreo-
montane/arctic-alpine lichens include seven
species with
a
'strong decrease'
viz.
Baeo-
myces roseus, Cetraria chlorophylla,
C.
islandica, Cladonia comma,
C.
squamosa,
Pseudevernia furfuracea
and
Pycnothelia
papillaria. Warm-temperate
and
tropical
species found
to be
increasing are most often
epiphytic, while terrestrial species with
this distribution
are
nearly absent
in the
Netherlands.
The
decreasing arctic-alpine/
boreo-montane species,
on the
other hand,
are mostly terricolous.
Estimated change related
to
ecological
determinants
The most parsimonious model resulting
from
a
multiple regression
of the
change
class numbers
on
Wirth's ecological deter-
minants
is
shown
in
Table
2.
These deter-
minants
are
available
for 180
species
out of
the original
329
species with change class
estimates,
but
because
of
missing values
in Wirth's determinants,
34
species were
excluded from
the
calculation.
The terms
for
'light demand', 'tempera-
ture preference'
and
'nutrient demand'
contribute significantly
to the fit of the
model. Change class
is
correlated positively
to 'temperature preference'
and
'nutrient
demand',
and
negatively
to
'light demand'.
Thus,
three independent trends have
occurred:
1,
species preferring warm
con-
ditions have increased proportionally more
than species preferring cool conditions;
2,
species preferring nutrient-rich habitats have
increased proportionally more than species
preferring nutrient-poor conditions;
3,
species preferring shade have increased
proportionally more than species preferring
direct sunlight.
The multiple regression confirms that
these three trends
are
independent factors.
No significant effect
was
found
for 'pH
preference';
the
significant simple corre-
lation between
'pH
preference'
and
change
class (r=+0-25, P=0-0007) disappeared
when 'nutrient demand'
was
included
in
multiple regression. Similarly,
the
simple
correlation between 'moisture-dependence'
and change class
(r=-0-21,
P=0-0088)
appeared
to be due to
'temperature
preference'.
Observed changes
in
epiphyte
frequency related
to
ecological
determinants
Long-term changes
of the 178
epiphytic
lichen species present
in the
monitoring pro-
gramme carried
out in the
province
of
Utrecht from 1979 onwards are presented
in
Table
3. It can be
seen that species diversity
as well
as the
frequency
of
many species
has
increased considerably.
The
total number
of
taxa present increased from
95 in 1979 to
172
in 2001
while
the
average number
of
taxa
per
site increased from 7-5
to
18-9.
The
146THE LICHENOLOGISTVol.
34
TABLE
3.
Long-term
changes
in
epiphytic
lichens
at
monitoring
sites
in
the province
of
Utrecht,
the Netherlands, 1979-2001
Species*
Anisomeridium biforme
A.
polypori
Arthonia muscigena
A.
pruinata
A.
radiata
A.
spadicea
Bacidia arnoldiana
s.l.§
B.
chloroticula
B.
neosquamulosa
B.
subfuscula
Buellia griseovirens
B.
punctata
Calicium viride
Caloplaca chlorina
C.
citrina
C.
decipiens
C.
flavocitrina
C.
holocarpa
C.
obscurella
Candelaria concolor
Candelariella aurella
C. reflexa
C. vitellina
C. xanthostigma
Catillaria nigroclavata
Cetraria chlorophylla
Chaenotheca brachypoda
C.
chlorella
C. chrysocephala
C.
ferruginea
C.
furfuracea
C.
stemonea
C. trichialis
Chrysothrix candelaris
Cladina portentosa
Cladonia caespiticia
C.
chlorophaea
C. coccifera
C. digitata
C.
floerkeana
C. glauca
C.
grayi
C.
humilis
C. incrassata
C. macilenta
C. polydactyla
C.
ramulosa
C. squamosa
C. sp.§
Cliostomum griffithii
Dimerella pineti
Diploicia canescens
1979
01
0-0
0-0
0-0
0-9
0-7
0-0
0-0
0-0
0-0
1-4
62-3
1-8
0-0
1-5
0-0
0-0
0-0
0-0
1-1
0-0
41
2-3
1-1
0-0
1-3
0-0
0-0
0-0
4-3
0-0
0-0
0-4
0-0
0-0
0-0
7-1
0-0
11
0-0
0-5
0-1
0-0
0-0
1-5
0-0
0-0
01
19-2
2-8
0-5
7-2
1984
01
0-6
0-4
00
1-4
0-7
3-9
0-0
0-0
0-0
5-1
681
21
0-0
2-4
0-0
0-0
0-0
0-4
1-1
0-6
3-9
6-7
3-5
0-0
10
0-0
0-0
0-0
5-1
0-1
0-0
0-3
0-0
0-3
0-0
2-6
0-0
0-6
0-0
11
0-1
0-0
0-0
0-2
0-0
0-0
00
22-1
3-9
2-0
91
Frequency
{%)%
1989
0-1
0-2
0-2
0-2
1-8
0-9
12-2
0-2
0-0
0-0
5-3
71-4
1-0
0-0
1-7
0-0
0-0
0-0
1-1
11
0-3
4-8
9-3
1-6
00
10
00
0-0
0-0
4-6
0-1
00
0-2
0-0
0-1
0-0
2-4
0-0
0-4
0-0
3-5
01
0-0
0-0
0-3
0-0
0-0
0-0
22-9
4-5
3-0
8-3
1995
01
5-7
0-2
0-2
2-0
4-7
53-8
0-5
0-2
0-0
9-9
79-2
0-6
0-1
6-3
0-2
2-2
0-9
2-2
7-4
3-4
37-2
20-2
5-3
0-0
0-7
0-5
0-4
0-4
9-2
0-3
0-5
2-4
0-5
0-3
0-0
111
0-3
0-2
0-9
3-1
0-1
00
0-2
2-4
0-2
0-6
0-0
23-8
9-0
16-3
141
2001
01
6-3
0-2
0-2
4-7
6-7
78-6
0-5
10-2
0-8
141
81-4
10
0-1
9-4
0-0
2-9
0-5
31
321
2-5
61-9
28-6
131
0-7
0-2
0-5
0-6
0-2
10-5
0-5
0-7
3-7
0-5
01
0-7
151
0-5
0-4
0-7
3-1
0-1
0-2
0-9
6-8
01
1-0
0-0
22-4
9-2
19-4
23-7
2002Lichens respond
to
global warming—van Herk
et al.
TABLE
3. Continued
147
Species*
Enterographa crassa
Evernia prunastri
Fellhanera bouteillei
F. subtilis
F. viridisorediata
Graphis elegans
G. scripta
Gyalideopsis anastomosans
Haematomma ochroleucum
Halecania viridescens
Hyperphyscia adglutinata
Hypocenomyce scalaris
Hypogymnia physodes
H. tubulosa
Imshaugia aleurites
Lecania cyrtella
L.
erysibe
L.
naegelii
L.
rabenhorstii
Lecanora aitema
L.
argentata
L.
barkmaniana
L.
carpinea
L.
chlarotera
L.
confusa
L.
conizaeoides
L.
dispersa
L.
expallens s.l.§
L.
hageni
L.
horiza
L.
muralis
L.
pulicaris
L.
saligna
L.
subcarpinea
L.
symmicta
Lecidella elaeochroma
L.
flavosorediata
L.
scabra
L.
stigmatea
Lepraria incana
L.
lobificans
L.
umbricola
Leproloma vouauxii
Micarea denigrata
M.
nitschkeana
M. peliocarpa
M. prasina
M.
viridileprosa
Mycoblastus fucatus
Ochrolechia androgyna
O. tnicrostictoides
O. turneri
Opegrapha atra
1979
0-1
41-8
0-0
00
0-0
00
01
0-5
0-8
0-0
0-0
5-4
43-3
7-9
0-4
0-2
0-0
0-1
0-0
3-3
0-3
0-0
31
19-2
0-0
80-7
9-5
56-8
0-2
0-0
0-2
0-8
0-0
0-0
1-2
18-9
0-0
0-0
0-0
55-8
0-0
0-0
0-0
0-0
0-0
0-0
0-8
0-0
0-0
0-0
00
0-0
0-5
1984
01
40-2
0-0
0-0
0-0
0-0
01
0-9
3-2
0-0
0-6
6-4
37-5
4-5
0-4
0-3
0-0
0-1
0-0
2-5
0-3
0-0
4-7
23-4
0-0
88-8
9-8
58-5
0-2
0-1
0-5
0-5
0-0
0-0
2-8
19-8
0-0
0-0
00
64-0
0-0
0-0
0-0
0-0
0-2
01
11
0-0
0-2
0-0
0-0
0-0
1-6
Frequency
1989
0-1
28-4
0-0
0-0
0-0
0-1
0-2
11
1-8
0-0
0-6
5-7
33-2
2-9
0-3
0-6
0-0
0-1
0-0
2-4
0-4
0-0
4-2
24-4
0-0
91-3
11-2
640
0-8
01
0-0
0-5
0-2
00
2-9
22-1
0-0
00
0-0
68-1
0-3
0-0
00
0-0
0-2
0-0
2-6
0-0
0-4
0-0
0-0
0-0
1-8
1995
0-2
28-9
01
0-2
0-5
0-1
0-2
7-6
1-3
0-3
3-7
10-2
22-5
8-0
0-3
1-6
0-2
01
0-0
1-2
0-2
1-5
9-1
37-5
0-0
35-3
23-5
81-6
24-8
0-3
1-2
3-0
2-3
0-1
8-2
42-7
4-2
11
0-0
61-9
0-9
0-0
00
10
2-0
0-8
7-3
0-0
1-4
11
0-6
0-1
3-0
2001
0-2
24-7
0-9
0-6
7-3
0-1
0-2
12-5
1-3
2-5
22-6
11-3
16-5
6-9
0-3
1-4
0-0
0-1
11
0-8
0-1
17-5
14-4
43-9
0-7
12-4
29-5
85-8
37-2
2-7
1-4
2-6
1-2
0-3
7-3
54-7
7-3
12-7
0-4
64-3
4-2
0-4
0-2
0-8
1-6
1-5
18-4
0-2
1-4
1-5
0-2
0-5
3-0
148THE LICHENOLOGISTVol. 34
TABLE
3.
Continued
Species*
O. herbarum
O. niveoatra
O. rufescens
O. varia
O. vermicellifera
O. vulgata
Parmelia acetabulum
P. borreri
P. caperata
P. elegantula
P. exasperatula
P. glabratula
P. laciniatula
P. pastilli/era
P. perlata
P. revoluta
P. saxatilis
P.
soredians
P.
subaurifera
P. subrudecta s.l.§
P. sulcata
P. tiliacea
P. verruculifera
Parmeliopsis ambigua
Pertusaria albescens
P. amara
P. coccodes
P.
leioplaca
P. pertusa
Phaeophysda nigricans
P. orbicularis
Phlyctis argena
Physcia adscendens
P. aipolia
P. caesia
P. clementei
P. dubia
P.
semipinnata
P. stellaris
P. tenella
P.
tribacia
P.
tribacioides
Physconia distorta
P. enteroxantha
P. grisea
Placynthiella icmalea
Platismatia glauca
Porina aenea
Protoparmelia hypotremella
P.
oleagina
Pseudevemia furfuracea
Psilolechia
lucida
Pyrenula nitida
1979
0-0
0-4
0-0
0-0
1-0
0-9
9-6
0-0
11
0-5
1-4
0-3
0-4
0-0
0-0
5-3
5-3
o-o
23-2
15-2
450
0-0
0-0
0-8
2-0
2-0
0-8
00
0-7
0-0
4-2
1-8
5-4
0-0
6-5
0-0
2-0
0-0
0-3
44-8
o-o
0-0
0-0
0-1
3-3
0-3
8-8