Table Of ContentRHODORA,
Vol. No. 928. 384-389, 2004
106,
pp.
NEBC NEWS
MEETING
September Crow
2004. Garrett began with show preview
a slide
to
Saturday morning marsh
the salt field trip, followed by photos meant to
crowd 2005 Amazon
interest the in his July trip to the connection
in
New
with York He
the Botanical Garden.
then introduced evening
the
New
speaker. Dr. Christopher Neefus from
the University of Hampshire,
who
spoke about "Living on the edge: Acclimation and adaptation of an
seaweed."
inlertidal
Chris began his talk with a photo of Louis H. Sullivan, who designed
th ,h
office buildings during the late 19 and early 20 centuries. Louis, who
added
often beautiful botanical ornamentation
the facades of
to his
was
buildings, considered modern
the father of the skyscraper, and was
mentor famous
to the architect Frank Lloyd Wright. More
importantly, as
Chris pointed out. he is credited with coming up with the concept of
"form
follows function," which Chris noted was an apt description of
the
evolution seaweeds.
inlertidal
ol'
In the 980s, Littler and Littler proposed a model of functional form
for
1
seaweeds,
hypothesizing
that physiological functions could be predicted
seaweeds'
via the morphological forms. Based on model,
this there are six
groups of seaweeds:
Sheet, Filamentous, Coarsely Branched, Thick
Leathery, Jointed Calcareous, and Crustose. shallow
In the subtidal zone,
—
the Thick Leathery group is well represented the species found there
tend to be tough, rubbery, and thick. These seaweeds have adapted to deal
with the mechanical stress caused by wave action, and can
tolerate
changes
temperature, reducing enzymatic when
in reactions too hot
is
it
or
cold.
In the inlertidal zone, seaweeds are submerged ocean waters only
in for
part of each tidal cycle, and as a result have had to evolve to tolerate an
extreme range of temperatures, from -20°C When
40°C. exposed
to
to
may
the they have
air, also to deal with high light levels and strong
ultraviolet radiation. Mechanical stress can be as high here as the
in
subtidal zone, but decreases with increasing elevation. Competition from
seaweeds
other and herbivory
also decrease
as elevation increases.
Common
species found in the intertidal zone include Ascophyllum
nodosum
and hnens
vesiculosus, both from the Thick Leathery group.
In the highest part of the intertidal zone, the environment often too
is
extreme One
for the adaptations described above. species found
there
is
Porphyra
linearis, a winter annual. This seaweed an alga from
the
is
Sheet group grows
on
that in thin layers the tops o[ rocks. Having
a
life
cycle that is restricted to winter and spring allows P. linearis to avoid the
384
NEBC
News
385
Meeting
20041
When
low
exposed
highest temperatures of the season. to air at
temperatures, this speeies freezes to the rocks, but is able to recover.
Perhaps even more amazing, P. umbilicalis and P. rediviva respond
when
resume growth
and can
extreme heat by drying out completely,
to
some amazing
have been
they are rehydrated. Chris noted that there
Porphyra growth following rehydration of dried
observations of the
herbarium specimens!
may
be
Since these species live so high up in the intertidal zone, they
meaning only have
submerged than one hour each day, they
for less
some Porphyra
a short amount of time to acquire nutrients. In response,
species have adapted to have the greatest rate of nutrient uptake within the
These can be stored
hour of exposure to a nutrient source. nutrients
first
seaweeds phycobilin-protein pigments that also serve as
within the as
pigments.
accessory photosynthetic
To competition, some Porphyra species have
deal with interspecies
even on
grow on organisms such barnacles, or
adapted epiphytically as
to
The Fucus
seaweeds including Fucus species. moist tissue of the
other
can pho-
Porphyra, extending the time the plant
helps hydrate the
seaweed
Chris went on describe other adaptations of
tosynthesize. to
morphology the harsh environment of the intertidal zone. Species with
to
and lanceolate forms have low drag, allowing them to handle high
linear
may "wave-pruned,"
of mechanical These species be but are
levels stress.
—
growing and recover quickly by virtue of their form they tend to be
fast
meaning impact
composed mainly of undifferentiated tissue, there is little
the plant part of torn away. Chris ended the talk by noting what
to if is
it
—
made
may most important function of Porphyra form ideal
be the its it
wrapper
use as a for sushi.
to
Forman
Orth, Recording Secretary.
Jennifer
September Field Trips. On Friday afternoon, September 10, Drs.
M
UNH
members
(UNH) led a party of approximately ten Club and several
students explore the seaweed flora of the rocky intertidal zone of Wall is
to
New Hampshire, and marsh of Brave Boat Harbor
Sands Rye, the
salt
in
Maine. The rocky zone of Wallis Sands a very
Kittery, intertidal is
in
wave and sand
exposed and disturbed environment, with high action
down
The group scrambled to the shoreline to observe the thick
scour.
were
washed
of wrack had ashore. Several species identified,
layer that
Laminaria saccharina
some noteworthy
with field characteristics.
(sugar kelp) large and ribbon-like, with a very thick and strong
is
3S6
Rhodora
(Vol. 106
Somewhat
holdfast. smaller, Laminaria digitata (kelp) has "digits" along
margin. Although Agarum
the not a true kelp, sp. (shotgun kelp) could be
by numerous
identified the holes Phycodrys
the rubens
in thallus. (sea
oak) one
is cell thick except along the midrib. Green, threadlike, tangled
of Chaetomorpha were
balls
sp. scattered about; Desmarestia exudes
sp.
sulfuric acid, and has minute spikclets on margin. Viva
the sp. (sea
lettuce) could be discerned by bright green
its flat, thallus.
A
few low
intertidal species were observed, including Fucus
spiralis,
Chondrus
crispus (Irish moss), Corallina, and Ascophyllum nodosum
(rockweed), which covered much
of the rock surfaces of the
intertidal
zone. high Porphyra
In the intertidal umbilicalis (nori) grew attached to
rocks. This economically important seaweed used making
is in sushi
wraps. Porphyra was observed
with variable pigmentation, from
purple
The
to green. light-harvesting pigment phycoerythrin gives the thallus
its
The
purple coloration. level of pigment depends on
the light level. Plants
growing
shaded
in areas are dark purple, while those exposed
to full
sunlight appear greenish. Pigmentation is also controlled by the amount
of may
nutrient availability; a decrease in pigmentation be associated with
low
nutrients.
For second
the part of the field Art Mathieson described
trip, the
first
habitat, morphology, and phenotypic variation of two seaweed
species,
Ascophyllum nodosum
and Fucus The
vcsiculosus. group then journeyed
down
through deciduous
forests Brave Boat Harbor among
to to search
Spartina patens for the seaweed. The Brave Boat Harbor marsh
has
salt
well-drained, sandy and
a substrate highly
is susceptible to erosion. Art
how
group
taught the to distinguish between ecads and germlings. The
former phenotypic
a variant of a species and caused by
is extensive
is
and
proliferation degeneration of detached fragments. Germlings could
be discerned by the presence of a distinct, discoid holdfast. Several
phenotypic were
variants found, including Ascophyllum nodosum
ecad
Fucus
scorpioides, vcsiculosus ecad and Fucus
volubilis,
cottonii.
On
Saturday morning, September Crow UNH,
Dr. Garrett of
1 1 ,
accompanied
by phytogcography
his class, led several Club members
to
explore the vascular flora of the salt marshes and sand dunes along the
New
Hampshire The
was
coastline. first stop to a salt marsh in Rye, just
south of Odiorne
State Park. Here, the group trekked through pure stands
of Spartina
patens, Distichlis spicata, and ./uncus Other
gerardii. species
encountered marsh
in the salt included Atriplex subspicata, dense
red patches of
ift
«
sempervirens,
Potentilla anserina, Triglochin maritima, Limonium
carolinianum, Suaeda
maritima, Plantago
maritima, and
Scirpus
NEBC
News 387
Meeting
2004)
was
some Ruppia maritima found. Garrett
robustus. In of the pools,
of
discussed the geographic distribution of several species, the role
community, and
environmental shaping type of plant
factors in this
adaptations of species to such conditions.
The group then met the Seabrook sand dunes. This area represents the
at
New
Hampshire.
largest coastal sand dune remnant in the state of Prior to
amount
community, sand dunes suffered a substantial
protection of the
this
ATV
of disturbance from (all-terrain vehicle) usage. Plants that colonize the
dunes adapted strong prevailing winds, storm activity, shifting sands,
are to
Ammophila and Lathyrus
spray, and high solar radiation. breviligulata
salt
were
japonicus are early colonizers of the foredune. Several species
Lechea
observed among the dunes, including Polygonella articulata,
Hypericum
Artemisia A. caudata,
maritima, Cakile edentula, stelleriana,
grew
Primus maritima intermixed
and Myrica pensylvanica.
gentianoides,
making of sweet and
with Toxicodendron radicans, the collection its
dunes
endeavor. Because the sand are a rare
succulent a risky
fruit
New
community Hampshire, area the location of several state-
in this is
Hudsonia
Cyperus and
including Aristida tuberculosa, grayi,
listed taxa,
among
Sunken hollows
tomentosa, of which the group observed. forests,
all
by
dunes where establishment of shrubs followed tree species,
the the is
A
among few members of group followed
were scattered the dunes. the
one of them. The sunken forest was cooler, being densely
Garrett into
and Pinus
shaded by canopy of Acer rubrum, Populus tremuloides,
a
Amelanchier
Shrub included stolonifera,
species Ilex verticillata,
rigida.
Vaccinium and Viburnum The forest floor was colonized by species
sp.
sp.,
$
Maianthemum
Mare Nazaire, Recording Secretary pro tempore.
th
New
October 2004. The England Botanical Club celebrated 1000
its
Massachusett:
meetin iinal organization at the
Members
Sanctuary Natick.
Wildlife in
members
enjoyed hors cToeuvres and displays of botanical art by club
show images and
Erika Sonder and Anita Sebastian, while a slide of
NEBC
documents from archives was displayed on a large screen.
the
Gilman welcomed everyone and
President Art
After a catered buffet,
"Away"
many meetings club has had
spoke briefly about the great the in
New He
and around England over the past few years. noted that the club
more 400 members; they and 350 institutions subscribe
has than
currently
Rhodora.
to
388
Rhodora
[Vol.
i()6
Past President Lisa Standley introduced the evening's speaker, Dr.
David
Barrington from the University o( Vermont. The club has had
the
honor Dave
of hearing speak on
several occasions over For
the years.
the thousandth meeting of a club that spends most of time asking why
its
grow
plants where they do, his talk was appropriately w The Big
titled
New
Thaw:
England
Flora Holocene."
the
in
Dave began New
his talk by noting that the mountaintops of England
NEBC
had captured many
the fascination of of the members. Ausable
first
Chasm New
York
serves one
in as striking lesson in the effects of time
A
and change on flora and fauna. deep and narrow divide almost mile
a
was
long, originally thought have been formed
to Oligocene
the
it in era,
but actually developed during the 10,000
last years.
In 1846, a beluga whale was unearthed during
the construction of
Vermont. The
a railroad in presence of such
a creature, referred to as the
Whale"
"Charlotte after the town near where was discovered, supports
it
was
the idea that there once an arm of the ocean the Champlain Valley.
in
While
studying from
flora the Pleistocene
glaciation, E. C. Pielou
maximum
concluded
that at glaciation (18,000 years ago), ice covered
much
of the terrain. However, during this ice age a series of large sandy
was
exposed
islands along the northeast Lake Champlain was
coast.
indeed at one time an arm of a giant sea whose land was compressed by
huge
the weight of
ice.
Dave
described the work of Norton who
Miller, has studied
the
New
recovering England
o( 12,000 13,000
flora to years ago, specifically
when
looking and where
at species were found. This work
uses both
pollen cores and macrofossils. The portions of a species' range where the
highest genetic diversity found are thought be those where
is to
populations have been around
the longest, especially those survived
that
through the ice age in what are termed ku refugia." For example, when
looking Fagus
at sylvatica in Europe, scientists found that genetic
diversity in this species is highest in the southernmost part of range.
its
This is hypothesized to be because subsets of the southern populations
uw
were
able to hide out" in refugia through the ice age. Another example
of
this pattern Asclcpias exaltata, an eastern North American milkweed
is
common
species very
that is in the South. In the North, rare and has
is
it
low
genetic variation
as well.
Saxifraga oppositifolia found Smugglers Notch Vermont on wet
is at
in
New
cliffs; the southern limit o[ distribution currently England.
its is in
A
group headed by Abbott
Dr. did a genetic study of which
this species,
was
found have
to spent the height of the Pleistocene era on exposed land
where now
in Siberia, the highest genetic diversity found. The
species
is
NEBC
News
Meeting 389
2004]
then repopulated the Arctic through North America and through Eurasia.
Dryas which
integrifolia another Arctic species for a set of refugia can
is
many
be hypothesized from genetic data. There are records of the pollen
two
of this species as well as fossils in refugia, with centers of diversity
being the high Arctic and Beringia.
Dave
then described the thesis research of Pete Walker, a University of
Vermont graduate who worked with Cathy Pete studied Ammophila
Paris.
breviligulata (beach grass), which widely distributed along the Atlantic
is
coast and Great Lakes regions. However, plants found along Lake
Champlain have been labeled as A. champlainensis There has been some
\
question as to whether this was a "true" species, though the Lake
Champlain plants flower in a different month. Pete determined that the
Great Lakes populations were actually morphologically intermediate
between the North Atlantic and Lake Champlain populations. likely
It is
that the Lake Champlain plants arrived with the ancient Champlain Sea
and diverged from other populations since the waters receded 10,000
salt
years ago. The North Atlantic populations have the highest genetic
diversity, likely because there was plenty of exposed sand on the coast
during the Pleistocene, providing a refugium. Lathyrus japonicus often
,
a companion of beach grass, grows on both the Atlantic and Pacific coasts
An
of North America. isozyme study showed that Pacific alleles were
common
most the north and dwindled the south, while Atlantic
in in
alleles were found only in the Atlantic populations, suggesting that there
two endemic
are actually centers for this species.
Dave
spent the part of his talk discussing several other interesting
last
case studies of plant species that survived the Pleistocene era in refugia,
He
including Adiantum pedatum. mentioned Hudsonia as a candidate
He
for future study of glacial refugia and Holocene migration. then took
several enthusiastic questions from the audience. The Club finished the
1000* meeting celebration with an excellent dessert table and a sparkling
cider
toast.
Forman
Orth, Recording
•Jennifer Secretary.
