Dead Wood Comes Alive

Transcription

Dead Wood Comes Alive
Article
Dead Wood Comes Alive
Research into cryptogamic diversity of beech forests across Europe led to a visit
to Epping Forest for the authors Erik Aude, Klaas van Dort, Rasmus Fuglsang
rMap 1. European beech areas (in green, data EUFORGEN) and sites visited by Beech Boys (red dots). M. Christensen
Frederiksen and Sally Gadsdon, who report on the groups findings.
and Sweden (see Map 1). In addition to dead
wood communities, the epiphytic flora of the
sites was studied.
The research is trying to disentangle
biodiversity patterns with regards to bryophytes,
fungi and lichens growing on dead wood and
old trees on a European scale. More specifically,
whether the influences of long term history,
climate and human impact can be discerned on
the biodiversity patterns of these taxa. Sites were
selected across Europe to cover as wide a climatic
gradient within the distribution of beech forests
as possible. Over the last 10 years the Beech
Boys have visited almost 100 forest reserves in
Europe. Of the Beech Boys, Erik Aude, Klaas
van Dort and Rasmus Fuglsang Frederiksen
were responsible for recording bryophytes (and
lichens!).
rFig. 1 The Beech Boys (& girl!) at Burnham Beeches. Sitting on beech log: (left to right) Claus Baessler, Klaas van Dort, Erik
Aude, Nerea Abrego Antia, Örjan Fritz. In front of beech log: (left to right) Morten Christensen, Martyn Ainsworth (guest
Beech Boy), Rasmus Fuglsang Frederiksen. M. Christensen
W
hilst many people dream of working
in nature conservation, even those
working at a European renowned
site can forget just how a special place it is. In
this case it is Epping Forest which lies across the
boundary of Essex and Greater London. Being
a well-known site, it often receives national
and international visitors. In 2014 a group of
European ecologists visited the site as part of a
project studying the cryptogamic flora of dead
beech wood. Other sites they included in their
visit to Britain were the New Forest (Denny Wood
and Wood Crates), Savernake (Wiltshire), Lady
Park Wood (Gloucestershire/ Monmouthshire)
and Burnham Beeches (Buckinghamshire).
The project background
This visit was part of on-going research into
beech woodlands. It started with research into
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FieldBryology No113 | May 15
the diversity of dead wood inhabiting species
in many of the best preserved beech forests in
Belgium, Denmark, England, Hungary, Slovenia
and The Netherlands. This was funded by the
European Community as part of the Nat-Man
project (Nature-based Management of beech in
Europe) and it finished in 2005. From this some
enthusiastic experts on cryptogams continued
recording inventories in beech dominated
ancient woodlands on a voluntary basis, under
the name of “the Beech Boys” (beechboys.eu).
Yes, pun intended. The original core of the Beech
Boys survives and people join the group for one
or several years, with new members welcome.
Between 2005 and 2014 the Beech Boys
have systematically collected data on species
composition of epixylic communities in ancient
woodland reserves in Austria, Bulgaria, Croatia,
Czech Republic, Germany, Italy, Slovakia, Spain
The visit to Britain
The British sites were visited in late October
2014. Local managers and administrators
warmly welcomed the group at the various sites.
During the trip the Beech Boys were joined
by Martyn Ainsworth, fungi expert from Kew
Gardens. In Wales George Peterken, the wellknown conservationist of natural woodlands,
showed them ‘his’ Lady Park Wood. The group
enjoyed their short trip to England, not least as
“the exploitation of local food and drinks made
the trip very rewarding indeed”.
In general, dead wood specialists were very
poorly represented at all sites. Most beech logs
showed the effects of black rot fungi (Eutypa
spinosa), which makes the wood hard and
creates a very unfavourable substratum for
epixylic bryophytes. As was to be expected the
epiphytic lichen flora was very good in the New
Forest, Wood Crates being among the “best”
beech forests in Britain with many species of
conservation concern, several figuring in Rose’s
Revised Index of Ecological Continuity list
(Coppins & Coppins, 2002). The remaining
four sites were extremely poor. Beech stems in
Burnham Beeches and Epping Forest were almost
devoid of epiphytes, even nitrogen loving ones
were scarce (but abundant on trees in gaps and
along the forest edge). A preliminary list of the
species found on beech logs and wind-thrown
root-balls at Epping is given below (Table 1,
FieldBryology No113 | May15
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FieldBryology No113 | May 15
bryophyte
Zygodon viridissimus
Lophocolea bidentata
What’s the outcome?
One of the main aims is to produce illustrated
manuals on cryptogamic indicator species
dependent on dead beech wood. There will be
three volumes, the first dealing with bryophytes,
the second focusing on fungi, and the third will be
on all epiphytes as ancient woodland indicators
in (semi) natural European beech woodlands.
These manuals are aimed at forest managers,
staff at national parks and forest reserves, as well
as people interested in cryptogams in general.
Several scientific papers on the subject have
already been published (see references) and there
are more to follow (will be listed on beechboys.
eu).
The future
In 2015 the Beech Boys are preparing for a trip
to Romania. In the future, a visit is planned
to the important Ukrainian reserves, among
which is the vast Uholka forest, the largest virgin
beech forest in Europe and a UNESCO world
heritage site. Also the best sites of Germany and
France, including the famous La Tilleul reserve
rFig. 2. Klaas surveying beech dead wood in Epping Forest.
S. Gadsdon
at Fontainebleau, await further investigation.
After this there will be more data analysis to
complete, so the manuals are several years off
publication. But for this one day, we knew that
a little part of Epping Forest had had a thorough
bryological going-over! And we remembered that
Epping Forest is very special.
sFig. 3. Erik, Klaas and Rasmus worshiping at the altar of Zygodon forsteri. S. Gadsdon
Dicranoweisia cirrata
bryophyte
bryophyte
bryophyte
Zygodon conoideus
Zygodon forsteri
lichen
Leucobryum glaucum
lichen
Cladonia fimbriata
Lepraria lobificans
lichen
Cladonia coniocraea
Kindbergia praelonga
Lepraria incana
bryophyte
Cephalozia bicuspidata
Candelaria concolor
lichen
bryophyte
bryophyte
bryophyte
bryophyte
Ulota bruchii
Ulota crispa
bryophyte
lichen
bryophyte
bryophyte
Rhizomnium punctatum
Thuidium tamariscinum
bryophyte
some species still awaiting identification).
But the trip to Epping Forest was not without
a highlight, Erik, Klaas and Rasmus were taken
to a nearby patch of Forster’s Knothole Moss
Zygodon forsteri, (Fig. 3). Epping Forest has the
largest population of Z. forsteri in the UK with
158 known colonies on 77 trees (2008 survey,
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Adams 2008). Burnham Beeches
and the New Forest are the only
other two UK sites where this beech
specialist can be found. It has fairly
specific habitat requirements, only
being found on parts of the tree
which are regularly wet or hold
water such as root knotholes or
stemflow routes. This was a new
species for both Erik and Rasmus.
Klaas said “according to literature
Zygodon forsteri is widespread,
but rare, in Europe, ranging from
eastern Bulgaria to western Portugal
and from southern Spain as far
north as Denmark. Interesting is
the shift in sporophytes throughout
its range. Fagus sylvatica is by far
the commonest host in the north,
several species of Quercus are used
in the southern part of its range,
where beech reaches its southern
limits. Before Sally Gadsdon showed
it to us I had seen it only once,
in Basaula, a small forest reserve
occupying a sheltered canyon in
the foothills of the Sierra de Urbasa
(Navarra). It was abundantly fruiting
and easily spotted on several stems
of Quercus faginea and Quercus ilex.
The wet rim of rot holes is the usual
microhabitat to look for it. In Spain
it grows well above the ground,
e.g. where branches have broken off from the
stem, quite unlike its usual habitat in England
where root systems at ground level seem to be
preferred. Zygodon forsteri is also known from
Fontainebleau. Thanks to our field training in
Epping we are quite confident to spot it there
too!”
bryophyte
Hypnum cupressiforme
Isothecium myosuroides
bryophyte
bryophyte
Campylopus introflexus
lichen
Porina aenea
bryophyte
Hypnum andoi
bryophyte
Calypogeia arguta
Campylopus flexuosus
lichen
bryophyte
Polytrichum formosum
bryophyte
Herzogiella seligeri
Bryum flaccidum
bryophyte
Physcia tenella
Frullania dilatata
Brachythecium velutinum
bryophyte
bryophyte
bryophyte
bryophyte
Mnium hornum
Orthotrichum affine
bryophyte
Fissidens taxifolius
bryophyte
Brachythecium salebrosum
Fissidens bryoides
Brachythecium rutabulum
bryophyte
bryophyte
bryophyte
bryophyte
Lophocolea heterophylla
Metzgeria furcata
bryophyte
bryophyte
Eurhynchium striatum
bryophyte
Atrichum undulatum
Dicranum scoparium
lichen
Arthonia spadicea
Table 1. Preliminary species list for species found on beech logs and wind-thrown root-balls at Epping
Forest (some species still awaiting identification).
Dead Wood Comes Alive
FieldBryology No113 | May15
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Article
wFig. 3. Tubers of
Pleuridium acuminatum
(10 divisions of scale =
100 µm) N.J. Law
Rhizoidal tubers in Pleuridium
acuminatum
Nick Law and Tom Blockeel report the
discovery of rhizoidal tubers in this moss in
Britain in a stubble field in South Derbyshire
rFig. 4 (left). Zygodon forsteri (darkest green moss) growing on a beech root knothole. S. Gadsdon. rFig. 5 (right). Zygodon
forsteri. K. Adams
Adams, K. (2008). The status and distribution of the Schedule 8
Red Data moss Zygodon forsteri (With.) Mitt. In Epping Forest.
A report for the City of London.
& Christensen, M. (2005). Diversity and composition of
dead wood inhabiting bryophyte communities in European
beech forests. Boletín de la Sociedad Española de Briología 2627: 85-102.
Coppins, A. M. & Coppins, B. J. (2002). Indices of Ecological
Continuity for Woodland Epihytic Lichen Habitats in the
British Isles. British Lichen Society.
Spier, L., van Dort., K., Fritz, Ö. (2008). A contribution to
the lichen mycota of old beech forests in Bulgaria. Mycologia
Balcanica 5: 141-146.
References
EUFORGEN. European Forest Genetic Resources Programme.
Distribution maps. www.euforgen.org/distribution-maps/
Heilmann-Clausen, J., Aude, E., van Dort, K., Christensen,
M., Piltaver, A., Veerkamp, M., Walleyn, R., Siller, I.,
Standovar, T. & Ódor, P. (2014). Communities of woodinhabiting bryophytes and fungi on dead beech logs in
Europe – reflecting substrate quality or shaped by climate
and forest history? Journal of Biogeography, doi: 10.1111/
jbi.12388
Ódor, P., Heilmann-Clausen, J., Christensen, M., Aude, E.,
van Dort, K. W., Piltaver, A., Siller, I., Veerkamp, M. T.,
Walleyn, R., Standovar, T., van Hees, A. F. M., Kosec, J.,
Matocec, N., Kraigher, H. & Grebenc, T. (2006). Diversity
of dead wood inhabiting fungal and bryophyte assemblage in
semi-natural beech forests in Europe. Biological Conservation
131: 58-71.
Ódor, P., van Dort, K. W., Aude, E., Heilmann-Clausen, J.
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FieldBryology No113 | May 15
Erik Aude, Consultant Bryologist and owner,
HabitatVision, (www.habitatvision.dk),
Denmark
e eau@habitatvision.dk
Klaas van Dort, Consultant Bryologist and
owner, Forestfun, The Netherlands
e klaasvandort@online.nl
Rasmus Fuglsang Frederiksen, Consultant
Bryologist and owner, VINK, Denmark
e rasmusfuglsangfrederiksen@gmail.com
Sally Gadsdon, Environmental Stewardship
Officer, Epping Forest, City of London
e sally.gadsdon@cityoflondon.gov.uk
R
Introduction
isse (1987) provided a review of the
published knowledge of tubers (rhizoidal
gemmae) in mosses from the time of
their probable first description by T.F.L. Nees
von Esenbeck in 1818 up to March 1987. This
review encompassed key papers such as that
by Whitehouse (1966), which described and
illustrated the rhizoidal tubers of twenty-nine
species of European mosses. Risse’s review
(1987) listed 82 European mosses and 36
extra-European mosses from which tubers had
been confirmed. Neither of these lists included
Pleuridium acuminatum although, as noted by
Risse, H. Koch had long before reported the
occurrence of tubers within the genus (Koch,
1842). Their occurrence within European
populations of P. acuminatum was confirmed by
Arts & Risse (1988), following the discovery by
R. Düll in 1986 of a tuber-bearing herbarium
specimen of P. acuminatum, collected by F. Neu
and originally determined as P. subulatum. Arts
& Risse detected rhizoidal tubers in 11 out of 15
specimens of P. acuminatum but were unable to
find them in 28 specimens of P. subulatum that
they examined.
Smith (2004) indicates that rhizoidal tubers
sometimes occur in P. acuminatum and provides
a description of them, but he does not indicate
whether this observation is based on material
from Britain or continental Europe, and he does
not illustrate the tubers. Porley (2008) stated
that “large, brown, variably-shaped tubers,
surrounded by a hyaline layer, occur commonly
on continental specimens of P. acuminatum
but have not been reported in the British Isles
and should be looked out for”. He provided a
photomicrograph of a tuber from a Portuguese
specimen. Finch & Blockeel (in Blockeel et al.,
2014) also highlight the frequency of rhizoidal
tubers on continental specimens and suggest that
they ‘…doubtless occur in Britain’.
Pleuridium species in arable land
Both P. acuminatum and P. subulatum occur
within arable fields but P. acuminatum appears
to do so less frequently according to the results
of the Survey of Bryophytes on Arable Land
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