| Click to
enlarge…
|
Since
1987 I have been working on the National Science Foundation supported
Arctic Long-Term Ecological Research program.
This research program is based at the Toolik Lake Field Station
on the North Slope of Alaska near the Prudhoe Bay oil fields and the Arctic National Wildlife Refuge.
My contributions to this multi-institutional and multi-disciplinary
project have focused on linkages between benthic primary production
and nitrogen cycling in Arctic tundra streams. The key findings of
this on-going research is that small changes in the balance of nitrogen
and phosphorus inputs have profound influences on the structure and
function of the benthic autotrophic community structure and function.
For more information on this fascinating story, click here.
In a related effort, I have been studying how hyporheic (sub-stream)
dynamics influence nutrient processing in arctic tundra streams.
The key findings of this on-going research are that hyporheic processes
are of fundamental importance to a clear understanding of carbon,
nitrogen, and phosphorus turnover in arctic tundra streams; a finding
that was unexpected. In August 2003 I received funding for a new research
initiative - the
Arctic Hyporheic Project - with colleagues from Utah State University
and Boise State University (Idaho) to study the potential impacts
of climate change in the Arctic on the hydrodynamics and biogeochemistry
of streams on the North Slope of Alaska. This project will run through
August 2006. For more information on the hyporheic story in the Arctic,
click here.
Both of these efforts supported the development of the LINX-1
project. This was a collaborative project in which a group
of collaborators from across the US used exactly the same experimental
approach and analytical protocols to examine key factors controlling
nitrogen cycling in headwater streams. This unique project
relied on innovative modeling approaches and field experiments using
15N, a stable isotope of nitrogen. A good summary
of this project with links to the numerous papers published from this
effort can be found in the Science article by Peterson et al. cited
below.
In 2005 I began a new collaborative
effort with the National Park Service (NPS) and colleagues from the
Utah State University, the University of Alabama, the University of
Alaska - Fairbanks, and the Marine Biological Laboratory. This effort
is to help the NPS determine how to assess the freshwater resources
in the Arctic Parks within the NPS System (Gates of the Arctic, Noatak,
Kobuk, Cape Krusenstern, and the Bering Land Bridge). The purpose
of this assessment is to provide a baseline for future assessments
of climate and other anthropogenic influences on the NPS system. The
initial 2005-2006 effort is focused on an expedition to the upper
Noatak River. Information about this expedition can be found here.
Related Web Sites
The Arctic LTER home:
http://ecosystems.mbl.edu/ARC/
The Toolik Field Station: http://www.uaf.edu/toolik
The LINX-1 Project: http://sparc.ecology.uga.edu/webdocs/linx
The
Arctic Hyporheic Project (Main
and Supplementary
pages)
Noatak
River Freshwater Vital Signs Initiative
ARCSS
Thermokarst Project (Private Team Page)
Key paper and reports
Bowden, W.B., B.J.
Peterson, J. Finlay, and J. Tucker. 1992. Epilithic oxygen
production and consumption in a fertilized arctic stream. Hydrobiologia
240:121-131. Also reprinted in W.J. O'Brien (ed.) Toolik Lake: Ecology of an Aquatic Ecosystem in Arctic Alaska. Development
in Hydrobiology. Volume 78. Kluwer Academic Publishers.
Boston.
Hershey, A., W.B. Bowden, L. Deegan, J.E. Hobbie, B.J. Peterson, G.
Kipput, G. Kling, M. Lock, M. Miller, R. Vestal. 1997.
The Kuparuk River: a long-term study of biological and chemical processes
in an arctic river. In: A. Milner and M. Oswood (eds.).
Freshwaters of Alaska. Ecological Synthesis. Ecological
Studies Series, Volume 119. Springer-Verlag . New York..
Bowden, W.B., J.C. Finlay and P.E. Maloney. 1994. Long term
effects of PO4 fertilization on the distribution of bryophytes in
an arctic stream. Freshwater Biology 32:445-454.
Finlay, J.C. and W.B. Bowden. 1994. Controls on
production of bryophytes in an arctic tundra stream. Freshwater
Biology 32:455-466.
Hobbie, J. E., L. A. Deegan, B. J. Peterson, E. B. Rastetter, G. R.
Shaver, G. W. Kling, W. J. O'Brien, F. S. T. Chapin, Michael C. Miller,
G. W. Kipphut, W. B. Bowden, A. E. Hershey and M. E. Mc Donald. 1995. Long term measurements
at the Arctic LTER site, pp. 391 409. In: T. M. Powell and J.H.
Steele (eds.), Ecological Time Series. Chapman and Hall, New York .
Harvey, C.J., B.J. Peterson, W.B. Bowden, L.A. Deegan, J.C. Finlay, A.E. Hershey, and M.C. Miller.
1997. Organic matter dynamics in the Kuparuk River , a tundra river in Alaska , USA . Journal of the North American Benthological
Society 16:18 -23.
Arscott,D.B, W.B. Bowden, J.C. Finlay. 1998. Comparison
of epilithic algal and bryophyte metabolism in an arctic tundra stream,
Alaska . Journal of the North American Benthological
Society 17(2): 210-227.
Harvey, C.J., B.J. Peterson, W.B. Bowden, A.E. Hershey, M.C. Miller,
L.A. Deegan, and J.C. Finlay. 1998. Biological
responses of Oksrukuyik Creek, a tundra stream, to fertilization.
Journal of the North American Benthological Society 17(2): 190-209.
The Stream Bryophyte Group (Bowden, organizer and lead author).
1999. Roles of bryophytes in stream ecosystems. Journal
of the North American Benthological Society. 18(2):151-184
Wollheim, W.M., B.J. Peterson, L.A. Deegan, M. Bahr, M. J.E. Hobbie, D.
Jones, W.B. Bowden, A.E. Hershey, G.W. Kling, and M.C. Miller.
1999. A coupled field and modelling approach for the analysis
of nitrogen cycling in streams. Journal of the North American
Benthological Society 18(2) 199-121.
Arscott, D.B., W.B. Bowden, and J.C. Finlay. 2000. Effects
of desiccation and temperature/irradiance on the metabolism of 2 Arctic
stream bryophyte taxa. Journal of the North American Benthological
Society 19(2):263-273.
Hobbie, J.E. B.J. Peterson, N. Bettez, L.Deegan, W.J. O'Brien, G.W.
Kling, G.W. Kipphut , W.B. Bowden, and A.E. Hershey. Impact of global
change on the biogeochemistry and ecology of an Arctic freshwater
system. Polar Research 18 (2):207-214
Tank, J.L., P.J. Mulholland, J.L. Meyer, W.B. Bowden, J.R. Webster,
B.J. Peterson, and D. Sanzone. 2000. Contrasting food
web linkages for the grazing pathways in 3 temperate streams, using
15N as a tracer Verh. Internat. Verein. Limnol.. Proceedings
of the XXVII Congress of the International Association of Theoretical
and Applied Limnology, Dublin, Ireland , 1998.
Peterson, B. J., W. Wollheim, P. J. Mulholland, J. R. Webster, J.
L. Meyer, J. L. Tank, N. B. Grimm, W. B. Bowden, H. M. Valett, A.
E. Hershey, W. B. McDowell, W. K. Dodds, S. K. Hamilton, S. Gregory
and D. J. D’Angelo. 2001. Stream processes alter
the amount and form of nitrogen exported from small watersheds. Science
292: 86-90.
Wollheim, W.M., B.J. Peterson, L.A. Deegan, J.E. Hobbie, B. Hooker,
W.B. Bowden, K.J. Edwardson, D.B. Arscott, A.E. Hershey, and J. Finlay.
2001. Influence of stream size on ammonium and suspended particulate
nitrogen processing. Limnology and Oceanography 46:1-13.
Mulholland, P.J., C.S. Fellows, J.L. Tank, N.B. Grimm, J.R. Webster,
S.K. Hamilton, E. Marti, L. Ashkenas, W.B. Bowden, W.K. Dodds, W.H.
McDowell, J.L. Meyer, and B.J. Peterson. 2001. Controls on stream
metabolism examined in an inter biome comparison. Freshwater
Biology 46(11):1503-1517.
Dodds, W.K., A.J. López, W.B. Bowden, S. Gregory, N.B. Grimm, S.K.
Hamilton, A.E. Hershey, E. Martí, W.H. McDowell, J.L. Meyer, D. Morrall,
P.J. Mulholland, B.J. Peterson, J.L. Tank, H.M. Valett, J.R. Webster,
W. Wollheim, 2002. N uptake as a function of concentration in streams.
Journal of the North American Benthological Society 21(2) 206–220.
Findlay, S., J. Tank, S. Dye, H.M. Valett, P. Mulholland, W.H. McDowell,
S. Johnson, S.K. Hamilton, J. Edmonds, W.K. Dodds, W.B. Bowden.
2002. Bacterial and fungal biomass in detritus-based microhabitats
of headwater streams. Microbial Ecology 43:55-56.
|