Background Information
This preserve's unique features make it one of the best sites to study
a naturally functioning tallgrass prairie in the world. The TGPP is
one of the largest unplowed tallgrass prairie preserves with an extent
of 15,200 ha, and it is embedded within the last large remnant tallgrass
prairie in the world (the Flint Hills). Steinauer and Collins (1996)
speculate that the large size of the preserve and intact matrix of tallgrass
prairie surrounding the preserve should counteract local species extinction
by encompassing a wide range of habitat types and ensuring an influx
of native propagules from the regional species pool. In 1993 the Nature
Conservancy began implementing a more natural disturbance regime on
the landscape in which annual burning and cattle grazing were gradually
replaced by randomized less frequent burning and bison grazing (Palmer
et al. 2000b). The temporal distribution of prescribed fires throughout
the year is designed to mimic the prehistoric fire regime, with the
majority of fires occurring during the dormant season (winter), but
a sizable minority occurring at other times (Hamilton 1996). The spatial
distribution of prescribed patch burns at TGPP are determined using
a randomization procedure which is weighted toward sites that have accumulated
large amounts of litter. This method creates a more natural mosaic on
the landscape than more rigidly prescribed fire regimes that are used
at other tallgrass preserves such as Konza prairie. Grazing in the TGPP
was initially divided between cattle and bison, with the goal of increasing
the area allotted to the bison as the herd increased in size (Palmer
et al. 2000b). The bison are allowed to roam freely to sites they prefer
which are those that have been recently burned (Biondini et al. 1999).
Also it is important to note that bison are expected to effect on the
vegetation differently then cattle because bison prefer graminoids more,
create large wallow depressions, and their shedding and horning behaviors
are likely to have strong effects on the landscape (Palmer et al. 2000b).
By allowing some patches to remain unburned (and therefore ungrazed)
for different periods of time the Nature Conservancy hopes to create
a shifting-mosaic vegetation pattern that reflects the evolutionary
landscape and therefore promotes native plant diversity (Hamilton 1996).
Research Questions
Recent literature has theorized that using management techniques that
recreate evolutionary patterns of disturbance and herbivory in the Great
Plains will increase the heterogeneity of the landscape and therefore
increase diversity of plants that are indigenous to this area (Fuhlendorf
and Engle 2001). Palmer et. al. (2000a) recognize that that this is
a reasonable hypothesis to apply to the management of the TGPP, but
that it must be tested once enough years of data have accumulated. My
mentor, Michael Palmer, began collecting data at the preserve beginning
in 1993, now more then ten years later it is timely for me to address
the following questions:
1) If you build it will THEY come... (Margret Palmer et al.
1997). Is the management regime promoting native diversity and decreasing
exotic diversity and abundance? More specifically what is the effect
of varying the amounts of time since last burned on plant composition
at a site, and do bison affect plant diversity differently then cattle
grazing?
2) Gradient analysis - A related question which is also important
for management is along what environmental and fire-grazing gradients
do certain plant associations appear to be located?
In order to address these questions I will use a combination of 10
years of permanent plot data that Michael Palmer has collected with
the addition of transect data that I will collect myself at the preserve.
Twenty quadrats were placed randomly on the landscape
and have been resampled annually since the TNC began their management
regime at the TGPP. These data will provide fine scale spatial and temporal
information about patterns of native diversity. Also 252 permanent quadrats
established across the TGPP have not yet been resurveyed. I will resample
these permanent plots in order to determine long-term changes in vegetation
composition. The transects that I will establish at the preserve will
enable me to address how native plant diversity is changing across different
environmental gradients. At each of my quadrats and along my transects
I will collect data on environmental variables (soil moisture, Ca, Mn,
Fe, and topography) that have been identified as important in determining
the local plant assemblages at the TGPP (Palmer et al. 2000a).
Applications
My research will have direct application for restoration ecologists
who are attempting to restore native grasslands around the world. One
of the underlying tenets of restoration ecology is that ecosystems function
best under their recent evolutionary conditions in which they adapted
(Swanson et al. 1994). My research will directly test if this is indeed
true for a Tallgrass prairie ecosystem. Does restoring a natural disturbance
regime does actually enhance "naturalness" of vegetation,
and/or promotes native diversity? Another important application of my
research will be its usage as a baseline for other restoration projects.
White and Walker (1997) emphasize the importance of contemporary reference
points in which vegetation heterogeneity is described both a spatially
and temporally for the landscape; such points are necessary for guiding
restoration. Furthermore each reference site should be placed along
a gradient in which managers can extrapolate the findings from other
sites to their own site (White and Walker 1997). My research will generate
data for the natural end of the gradient, and it function as an extension
of much of the research that is carried out at Konza prairie which receives
a much more controlled management regime.
Literature Cited
Biondini, M. E., A. A. Steuter, and R. G. Hamilton. 1999. Bison use
of fire-managed remnant prairies. Journal of Range Management 52:454-461.
Fuhlendorf, S. D., and D. M. Engle. 2001. Restoring heterogeneity on
rangelands: ecosystem management based on evolutionary grazing patterns.
Bioscience 51:625-632.
Fuhlendorf, S. D., and D. M. Engle. 2004. Application of the fire-grazing
interaction to restore a shifting mosaic on a tallgrass prairie. Journal
of Applied Ecology 41:604-614.
Hamilton, R. G. 1996. Using fire and bison to restore a functional tallgrass
prairie landscape. in Transactions of the 61st North American Wildlife
and Natural Resources Conference. Wildlife Management Institute, Washington
D.C.
Knopf, F. 1994. Avian assemblages on altered grasslands. Studies in
Avian Biology 15:247-257.
Palmer, M. W., P. Earls, and J. R. Arévalo. 2000a. The vegetation
of the Tallgrass Prairie Preserve. unpublished report.
Palmer, M. W., T. Wohlgemuth, P. Earls, J. R. Arévalo, and S.
D. Thompson. 2000b. Opportunities for long-term ecological research
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Swanson, F. J., J. A. Jones, D. A. Wallin, and J. H. Cissel. 1994. Natural
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White, P. S., and J. L. Walker. 1997. Approximating nature's variation:
selecting and using reference information in restoration ecology. Restoration
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White, R., S. Murray, and M. Rohweder. 2000. Pilot analysis of global
ecosystems: grassland ecosystems. World Resources Institute, Washington,
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Williams, J. R., and P. L. Diebel. 1996. The economic value of the prairie.
Pages 18-35 in F. Samson and F. Knopf, editors. Prairie conservation:
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