Updates for Turner lab web site
MGT April 21, 2006
Research
Fire, vegetation and ecosystem processes in Yellowstone National Park
The size and severity of the fires that burned through Yellowstone National Park (YNP) and
surrounding lands (MAP) during the summer of 1988 surprised scientists, park managers and the
general public. The 1988 fires were a large, infrequent but natural disturbance that created a
complex landscape mosaic. Since the fires, Turner and colleagues, especially Dr. William H.
Romme (Colorado State University) and Dr. Daniel B. Tinker (University of Wyoming) have
been studying the effects of fire size and pattern on postfire vegetation and ecosystem processes.
Natural disturbances are key sources of heterogeneity in many ecosystems, yet the causes and
consequences of disturbances that are large, severe and infrequent are not well understood.
Read more about our research results… <<this goes to the page you already have>>
Current projects…<<see below for where this will go…>>
Current projects
Our current research in the Yellowstone region includes three major efforts.
How do disturbance-generate landscape patterns influence the spatial dynamics of ecosystem
processes? With funding from the Andrew W. Mellon Foundation, we are focusing on the
interactions between vegetation and ecosystem processes, with particular emphasis on nitrogen
cycling and the role of post-fire coarse wood, following stand-replacing fire. This study has
continued a main focus on areas burned by the 1988 fires, but we have also initiated studies in
areas burned during 2000 and 2003 as well as along a chronosequence of stand ages. In addition,
we studied within-stand spatial heterogeneity in soil processes and microbial communities in a
boreal forest that burned in 2001. We have completed much of the field data collection
associated with this work, and a number of analyses and papers are currently in preparation.
Currently, Liz Levitt (MS student) is examining whether the differences in stand structure and
aboveground net primary production observed in young post-fire lodgepole pine stands are
associated with difference in inorganic nitrogen availability across the Yellowstone landscape.
This study will contribute to understanding ecosystem processes in heterogeneous landscapes
and will be the first analysis to quantify variation in N availability among the post-1988 stands.
Read more….
Carbon cycling at the lanscape scale: the effect of changes in climate and fire frequency on age
distribution, stand structure and net ecosystem production (NEP). With funding from the Joint
Fire Sciences Program, we are examining carbon balance across the entire Yellowstone
landscape, how it might change under future climates and fire regimes, and how cycles of carbon
and nitrogen interact. Climate, fire (frequency and intensity), and forest structure and
development are strongly linked, but our knowledge of the interactions of these factors is poor.
We lack the ability to make robust predictions about how changes in climate will alter these
interactions and change the carbon balance of a landscape. Our objective is to estimate how
changes in fire frequency, pattern, and intensity will alter the distribution of forest age and
structure across a landscape and how these changes, in turn, will change the landscape carbon
balance. We are determining the current carbon balance for the Yellowstone National Park
(YNP) landscape and how much carbon was lost in the 1988 fires. We are also determining how
NEP will change for the YNP landscape with changes in climate and fire regimes by calibrating
the Century biogeochemical model to assess how changes in climate will alter NEP across stand
development, and using models developed in past research to simulate fire frequency, fire
spread, and the resulting landscape structure (the distribution of stand age and tree density) for
alternative climatic condition. We hypothesize that variation in tree establishment after a fire and
the legacy of the prior stand will control the trajectory of NEP through time, and that climate and
fire frequency will change the distribution of forest age and structure, and these changes will
alter net carbon storage for the landscape.
Currently, Erica Smithwick (postdoctoral research associate) is parameterizing the Century
ecosystem model to simulate patterns of carbon and nitrogen stocks and fluxes along a
chronosequence of stands in Yellowstone. We are particularly interest in simulating the
variability in initial post-fire pine seedling density to explore how structural heterogeneity affects
patterns of productivity and nutrient storage. Our collaborators include Drs. Michael Ryan
(USFS), Dan Kashian, Bill Romme and Dan Tinker. Read more…
Reciprocal interactions between bark be4etles and wildfire in subalpine forests: landscape
patterns and the risk of high-severity fire. Third, we are beginning (in 2006) studies of
disturbance interactions in the Greater Yellowstone Area, focusing on fire and insect outbreaks.
<<continue with the text from Martin; we will not post our proposal until it is actually funded,
however.>>
HOT LINKS:
Mellon proposal
Carbon proposal <<needs budgets etc. removed, I want science text and refs only>>
Land-water interactions in north temperate landscapes
The interfaces between aquatic and terrestrial ecosystems (i.e., riparian zones) are key functional
linkages in most temperate landscapes. Research in our lab has addressed a variety of land-water
linkages, including large river-floodplain systems along the Wisconsin River; the Northern
Highlands Lake District centered on Vilas County, Wisconsin; and lakes of the Madison area.
We collaborate closely in these studies with researchers at the UW-Madison Center for
Limnology, with our contribution typically focused on landscape patterns and processes (e.g.,
land-use change) or the drier side of the land-water interaction (e.g., riparian forests). Research
falls under the auspices of the North Temperate Lakes Long-term Ecological Research (LTER)
site; a Biocomplexity grant focusing on interactions among people and lakes; a spatially explicit
regional modeling study of hydrologic and biogeochemical fluxes in a land-water mosaic; a
study of critical thresholds related to eutrophication; and understanding the roles of flood regime
and land-use change along the Wisconsin River.
Current projects
Divergent dynamics: complex interactions of riparian land, people and lakes. <<can leave
existing text here, including the project web page, then continue with Anna’s paragraph
below.>>
Currently, Anna Marburg (PhD student) has investigated the effects of lakeshore development on
riparian forest and littoral coarse woody habitat. The main focus of her studies have been to
understand the importance of cross-boundary subsidies in understanding the impact of residential
development on ecosystems.
Alysa Remsburg (PhD student) has been building on the foundation of the biocomplexity and
NTL-LTER research to address the influence of habitat heterogeneity (especially vertical
vegetation structure) on dragonflies and damselflies (order Odonata), which are voracious
generalist predators <<continue with the text you had from Alysa>>
LINKS TO DOCUMENTS INCLUDE:
Water Mellon proposal.doc <<short proposal can be linked here>>
EPA Science only.pdf <<full proposal, science only>>
LINKS TO OTHER WEB SITES:
NTL LTER <<as we have them>>
Biocomplexity <<as we have them>>
WIRF <<is that link still live?>>
For prospective graduate students
For fall 2007, I anticipate accepting one or two PhD (or MS/PhD) students. I do not anticipate
accepting any students who only seek a MS. Prospective graduate students are encouraged to
peruse the research pages on the lab web site for an overview of current research projects. Areas
where I anticipate funding include: vegetation, disturbance and ecosystem processes in the
Greater Yellowstone Area; and land-water interactions in Wisconsin landscapes. Several
proposals are pending, and their status will influence the areas of emphasis that will best match
the current research directions in the lab.
Prospective students are also welcome to email Turner directly and as well as to contact current
or former students with questions. Please also see the web pages for the Zoology Department,
Madison Ecology Group, and The Graduate School.
Pictures:
SurveyLineFire_AK.jpg
Sampling in June 2003 within the Survey Line Fire in the Tanana
River Floodplain near Fairbanks, AK. The fire burned during
summer 2001 and we sampled soil processes within this stand from
2002-2003 (Smithwick et al. 2005).