Biology Reference
In-Depth Information
the growth of a number of epiphytic lichens. Epiphytic cyanolichens (
Erioderma sorediatum
,
Lobaria
oregana
,
L
.
pulmonaria
,
L
.
scrobiculata
,
Nephroma
bellum
,
N
.
helveticum
,
N
.
laevigatum
,
Pseudocyphellaria
anomala
,
P
.
antraspis
,
P
.
crocata
and
Sticta limbata
) contributed less to overall epiphytic biomass than
bryophytes and ferns but they were more abundant than chlorolichens. Of all the cyanolichens
L
.
pulmonaria
was the most abundantly represented in upper crowns with nearly three times as
much biomass as all cyanolichens put together.
L
.
oregana
is reported to grow in the middle to upper
crown.
L
.
scrobiculata
,
P
.
anomala
,
S
.
limbata
and
P
.
crocata
occurred nearly to the treetops categorized
under high exposue cyanolichens (Ellyson and Sillett, 2003).
However, studies on fl oristic and community composition of lichens in relation to environment
variables such as climate, geography and stand structure are lacking. Jovan (2002) fi rst conducted
landscape level of epiphytic lichen diversity of northern and central California. This was followed
by another such study highlighting regional variations in epiphytic marcolichen communities of the
same region depended on temperature, elevation and moisture variables. Cyanolichens constituted
the Greater Central Valley group dominated by other nitrophilous group of lichens. Representatives
of cyanolichens recorded were species of
Leptogium
and
Collema
. In the Northwest Coast Group,
cyanolichens had the highest species richness, diversity and abundance while nitrophiles are
rare (Jovan and McCune, 2004). Berryman and McCune (2006) compared epiphytic macrolichen
communities among forest types in the Blue River watershed of western Oregon. The cyanolichens
were largely limited to lower elevation forests (470-950 m) of the western hemlock series. The
diversity of cyanolichens was more in old-growth and mature stands at low elevations.
Phytogeographic and taxonomic studies on cyanolichens from central Europe revealed the
presence of
Anema nodulosum
,
A
.
prodigulum
,
Lempholemma intricatum
,
Leptogium ferax
,
Porocyphus
rehmicus
and
Zahlbrucknerella calcarea
(from Slovak Republic for the fi rst time),
Leptogium
biatorinum
and
L
.
magnussonii
(from Hungary) and
A
.
prodigulum
,
Heppia adglutinata
,
L
.
biatorinum
and
Psorotrichia
taurica
(from Czech Republic) (Czeika
et al
., 2004). The probability of detecting fi ve rare epiphytic
macrolichens can be improved by adopting model-based stratifi cation studies that enabled the
detection of cyanolichens
Nephroma laevigatum
,
N.
occultum
,
N
.
parile
,
Lobaria scrobiculata
and
Pseudocyphellaria rainierensis
in the Pacifi c North West. Tree models constructed by using topographic
and bio-climatic variables have revealed a direct correlation to the presence of common lichens such
as
L
.
oregana
,
L
.
pulmonaria
,
P
.
anomala
and
P
.
anthraspis
(Edwards
et al
., 2004).
xiii)
Endangered cyanolichens
:
Epiphyte abundance between stands may vary in age. Management
strategies have established a strong relationship between stand age and epiphytic biomass,
particularly for cyanolichens that are dominant in old-growth forests but nearly absent from young
stands (McCune, 1993). Thus the cyanolichens are generally restricted to or most abundant in
old-growth and mature forests. Genera such as
Erioderma
,
Leptogium
,
Lobaria
,
Nephroma
,
Pannaria
,
Parmeliella
,
Peltigera
,
Pseudocyphellaria
,
Solorina
and
Sticta
are abundantly represented in these
habitats. At one time very well documented on the deciduous and coniferous trees as epiphytes
in humid regions throughout Northern Hemisphere, cyanolichens are dwindling in their numbers
due to ecological disturbances such as acid rain, acidifi cation of the substratum and low buffering
capacity of coniferous bark (Nieboer
et al
., 1984; Farmer
et al
., 1992; Gauslaa and Holien, 1998). It is
also true for populations of cyanolichens, especially on conifers, in areas subject to acid rain in North
America and western and central Europe (Goward and Arsenault, 2002a). Similarly, the prospects
of fi nding the boreal felt lichen,
Erioderma pedicellatum
that typically colonizes coniferous trees in
Atlantic Canada are rare (Maass, 1980, 1983; Robertson, 1998; Sipman, 2002).
E
.
pedicellatum
is a
large- to medium-sized foliose cyanolichen. It grows on and attached to trees in cool moist areas. It