Subject: BEN # 102

From: [email-masked] (Adolf Ceska)
Date: 29 May 1995 21:45:48 -0700

BBBBB    EEEEEE   NN   N             ISSN 1188-603X
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BBBBB    EEEEE    NN N N             BOTANICAL
BB   B   EE       NN  NN             ELECTRONIC
BBBBB    EEEEEE   NN   N             NEWS

No. 102                              May 29, 1995

[email-masked]        Victoria, B.C.
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 Dr. A. Ceska, P.O.Box 8546, Victoria, B.C. Canada V8W 3S2
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RECONSTRUCTION  OF PAST SALINITY CHANGES IN MAHONEY AND KILPOOLA
LAKES, SOUTH-CENTRAL BRITISH COLUMBIA, CANADA
From: Heinrichs, *M.L., I.R. Walker, R.W.  Mathewes,  Department
of   Biological  Sciences,  Simon  Fraser  University,  Burnaby,
British Columbia, V5A 1S6, Canada, and J. P. Smol, Department of
Biology, Queen's University, Kingston, Ontario, K7L 3N6, Canada.
E-mail: Mark Lyle Heinrichs <[email-masked]>

The following is the abstract of a poster to be presented at the
joint meeting of the Canadian  Quaternary  Association  and  the
Canadian  Geomorphological  Research  Group  in St. John's, New-
foundland, June 5-7, 1995:

Preliminary  results  of  lake  salinity  reconstructions  using
fossil  remains  of  Chironomidae  (Diptera) indicate changes in
lake salinity occurring from early post-glacial periods  through
the mid and late Holocene.

Early  post-glacial sediments of Mahoney Lake show an assemblage
of chironomid head capsules typical of a  freshwater  community,
including   Sergentia,   Heterotrissocladius,   Cladopelma,  and
Dicrotendipes. This period of fresh water persisted  up  to  ap-
proximately  450  cm  (circa 9800 yr B.P.) and was followed by a
major shift in the assemblage occurring at approximately 400  cm
(circa  9000  yr  B.P.).  Chironomids  indicative of more saline
environments,  such  as  Cricotopus/Orthocladius   and   Tanypus
dominated and freshwater chironomids became absent at this time.
The chironomid-inferred salinity values derived from a salinity-
calibration  transfer  function  (Walker,  Wilson and Smol, sub-
mitted) also reflect the shift  from  freshwater  at  0.031  g/l
immediately  after  deglaciation,  to  saline water ranging from
10.0 to 55.2 g/l in subsequent periods. There is  evidence  sug-
gesting  slightly  less  saline  water  at  7.0 g/l in the 25 cm
interval (circa 400 yr B.P.)

Results from  early  post-glacial  sediments  of  Kilpoola  Lake
indicate  a  freshwater  community  which  included  Heterotris-
socladius, Dicrotendipes  and  Sergentia  having  a  chironomid-
inferred  salinity value of 0.035 g/l. Immediately thereafter, a
major fluctuation in the chironomid  assemblage  occurred,  with
inferred  salinity  values  increasing from 1.2 to 2.0 g/l, fol-
lowed by a rapid decrease to 0.037 g/l and  then  rebounding  to
2.0  g/l  at  397 cm. Heterotrissocladius and Dicrotendipes were
absent during the higher salinity periods,  and  the  assemblage
was   characterised   by   an   increase   in   Chironomus   and
Psectrocladius. Following this major fluctuation, the chironomid
assemblages had less variation until 267 cm, when  a  large  in-
crease  in  Cricotopus/Orthocladius  and Tanypus was observed; a
corresponding increase in salinity to  7.7  g/l  also  occurred.
This  higher  salinity  condition  prevailed  for a short period
until 257 cm, where the chironomid assemblage returned to condi-
tions similar to prior to 267 cm, with a corresponding  decrease
in  salinity  values  around 1- 2 g/l. Changes in the chironomid
assemblage occurred at 85 cm, with the  salinity  decreasing  to
0.7  g/l,  suggesting  a brief period of less saline water. Sub-
sequent intervals to present conditions are characterised by  an
assemblage   of   more  saline  tolerant  chironomids  including
Psectrocladius  and   Cricotopus/Orthocladius,   with   inferred
salinity values ranging from 1.4 to 3.5 g/l.

Salinity  change in lakes of semi-arid regions are recognised as
an indicator of climatic change due to high  evaporative  losses
and  low  precipitation (Hammer, 1990). Periods of high salinity
correspond to periods of warm temperatures due to an increase in
evaporation and a decrease  in  precipitation.  Periods  of  low
salinity  correspond to cooler temperatures due to a decrease in
evaporation and an increase in  precipitation.  Salinity  values
provide a valuable line of evidence in paleoclimatic reconstruc-
tion.  The  change  from  fresh  to  saline water in early post-
glacial sediments of both Mahoney and Kilpoola lakes  suggest  a
rapid  period of increasing temperatures. Severe changes follow-
ing the Mt. Mazama volcanic eruption are seen in  Kilpoola  lake
and to a lesser extent in Mahoney lake. High salinity values and
the  domination  of  Cricotopus/Orthocladius suggest that warmer
climate conditions  prevailed  for  some  time  thereafter.  The
decrease  in salinity of Mahoney lake circa 400 yr B.P. and that
around 85 cm in Kilpoola lake may correspond to similar  cooling
periods  seen  in  the  late  Holocene in other locations (King,
1980; Hebda, 1982).

References

Hammer,  U.T.  1990.  The  effects  of  climate  change  on  the
      salinity,  water  levels  and  biota  of  Canadian prairie
      saline lakes. Verh. Int. Ver. Limnol. 24: 321- 326.
Hebda, R.J. 1982. Postglacial history of grasslands of  southern
      British  Columbia  and adjacent regions. Grassland Ecology
      and Classification Symposium.
King, M. 1980 Palynological and  macrofossil  analyses  of  lake
      sediments  from  the  Lillooet area, British Columbia. Un-
      published Msc thesis.
Walker,  I.R.,  Wilson,   S.E.,   and   Smol,   J.P.   submitted
      Chironomidae  (Diptera):  Quantitative  palaeosalinity in-
      dicators for lakes of western Canada. Can. J. Fish  Aquat.
      Sci.

Note:  Copies  of  the conference programme, abstracts and field
guides (the  latter  represents  detailed  background  and  stop
descriptions  for both the Avalon Peninsula and West Coast field
trips - more than 100 pages) are offered for the basement  price
of  CDN$25.00  (which  includes  shipping  and handling) to non-
registrants of the conference. Please send  cheque  (written  on
Canadian  or  US  accounts),  made payable to CANQUA '95, to the
address below. Quantities are limited.
Trevor Bell, Department of  Geography,  Memorial  University  of
Newfoundland, St. John's, Newfoundland, Canada A1B 3X9
Tel: (709) 737-2525 Fax: (709) 737-4000
Email: [email-masked]

CLEARCUTTING AND EROSION IN SOUTHEASTERN ALASKA
From: Pamela Holly Pack <[email-masked]>
   in [email-masked]

Does anyone have any suggestions on recent information regarding
the  correlation of clearcutting and increased erosion/ sedimen-
tation in SOUTHEASTERN ALASKA? I have a good deal of info.  from
the 1970's, but I am looking for any powerful recent articles or
studies  that may be helpful in determining changes in landscape
patterns as a result of ANCA, ANILCA, as well as TTRA. This is a
rather broad request, but if anyone could point  me  toward  any
especially helpful documents I would appreciate it.

P.S. Sorry about the acronyms !! TTRA--the Tongass Timber Reform
Act  1990,  ANCSA--the  Alaska Native Claims Settlement Act, and
ANILCA--Alaska National Interest  Lands  Conservation  Act.  All
statutes  that  have  affected  landscape change in Southeastern
Alaska.

BIBLIOGRAPHY UPDATE FROM THE BIOLOGICAL CONSERVATION NEWSLETTER
From: Ellen Farr in [email-masked]

The cumulative Conservation Bibliography  from  this  newsletter
has  been  available  on  the  Smithsonian Institution's Natural
History Gopher Server since the fall of 1993. The list  has  now
grown to over 8000 references.

Gopher Server searches normally return a list of the first lines
of any items that meet the search criteria and each item must be
selected in turn to view the entire citation. We have now imple-
mented  a  new  search  option that will build a single document
>from  the search results for up to 200 records. This document can
be browsed on the screen, printed, or downloaded as a file.

The address for the Smithsonian's Natural History Gopher  Server
is   nmnhgoph.si.edu   port  70.  Look  under  Botany/Biological
Conservation/Conservation Bibliography. If you have a World Wide
Web Client, you can reach the material on the Gopher Server from
our department's Web Home Page. The URL is
http://nmnhwww.si.edu/departments/botany.html

ASSOCIATION OF SYSTEMATICS COLLECTIONS (ASC) ANNUAL MEETING

June 30-July 2. The 1995 Association of Systematics  Collections
(ASC)  annual  meeting  at UC Berkeley will be hosted jointly by
the  University  of  California,  Berkeley  and  the  California
Academy  of  Sciences.  The  meeting  will feature a workshop on
"Natural History Collections on the  Information  Superhighway."
For  registration  and  hotel information, contact ASC, 730 11th
St. NW, Second Floor,  Washington,  DC,  20001-4521;  Tel.:(202)
347-2850; Fax:(202) 347-0072.

CONTROL OF SCOTCH BROOM IN GARRY OAK GRASSLAND
From:  Eric Redekop, 2510 Asquith Street, Victoria, B.C., Canada
      V8R 3Y1. Phone: 604-595-7270

Garry Oak Grassland Rehabilitation Symposium: Control of  Scotch
Broom  (Cytisus  scoparius)  and  Other Invasive Exotic Plants -
presented by the Garry Oak Meadow Preservation Society.

Place: Dunsmuir Lodge, 1515 McTavish Road, P.O.Box 2369, Sidney,
B.C. Canada V8L 3Y3

Time: Saturday, June 10, 1995, 8:30 a.m. to 5:30 p.m.

Registration:  Please  register  by  June  6;  registration  fee
CDN$30.00  (includes  printed  materials,  refreshments,  buffet
lunch and field trip material) - make  cheques  payable  to  the
Garry Oak Meadow Preservation Society - should be sent to
2510 Asquith Street, Victoria, B.C., Canada V8R 3Y1.

Presentations:

"Identity  Crisis:  Do  We Know What We Want to Restore" by Hans
      Roemer
"Broom Control in B.C. Parks and Ecological  Reserves"  by  Ross
      Dawson
"Broom Removal from B.C. Highways" by Jean Anne Wightman
"Broom Control Research in Uplands Park" by Joel Ussery
"Biological Control of Noxious Weeds" by Brian Wikeem

Field Trip: Anderson Hill, Mount Tolmie and Christmas Hill.

Please note that SPACE IS LIMITED. If you would like to assure a
place, contact the organizers immediately by telephone:
Eric Redekop - 604-595-7270 or Tom Gilliespie - 604-361-1694

SOCIETY FOR RANGE MANAGEMENT SUMMER MEETING
>From  : Gail Berg <[email-masked]>

The  pacific  Northwest Section of the Society for Range Manage-
ment will be holding their annual Summer Workshop and Meeting at
Wasa, British Columbia this year. The dates are Thursday June 22
to Saturday June 24. The theme of the workshop will be  "Listen-
ing  Skills  to Foster Understanding of Rangeland Perspectives".
After the workshop, participants will visit  4  different  range
sites  and  various  user  groups will voice their desired range
management strategies  at  these  locations.  User  groups  will
include:  ranchers,  recreationists, forest companies, silvicul-
ture, hunter and guide outfitters, range  managers,  environmen-
talists  and  Fish and Wildlife biologists. For more information
contact    the    following:    Gail     Berg     (registration)
[email-masked] 604-342-2042 Greg Tegart 604-871-7611
Gary Tipper 604-489-8540 Mike Malmberg 604-426- 1535 A number of
post  meeting  tours  are  also  planned.  Registration  cost is
CDN$65.00.