 Home: Archives: 2002 Science Meeting Archives |
If you have not already done so, please stop by The Mountain main office
for check-in or a receipt if you need one. A representative in the office will
also be able to answer questions regarding hiking trails and other activities at
The Mountain.
Location:
Meeting Hall, The Mountain Retreat and Learning Center, near Highlands, NC
Presentation
Equipment: Please note that a slide projector, overhead projector, and digital
projector will be available for use throughout the meeting.
10:00
Introductions,
Logistics, and Opening Remarks (Coleman, Vose, Kloeppel,
Gragson, and Nancy Heath from The Mountain)
REU Update - Kloeppel
10:30
Renewal Proposal Presentation, Discussion, and Breakout Group Assignments
12:00
Renewal Proposal Breakout Group Work Sessions
12:30
- 1:15 Lunch at the The Mountain dining hall
1:30
Renewal Proposal Breakout Group Work Sessions (continued)
2:45
Renewal Proposal Breakout Group Reports
3:15
Break
3:30
Coweeta Watershed 7 Book Volume Update (Swank and Meyer)
3:45
Coweeta Data Management: Past, Present, and Future (Rouhani)
4:15
Status Report for Coweeta GIS: Current status, recap of efforts in 3rd
& 4th
Quarters 2001, and future efforts (Collins)
5:00
Pre-Dinner
Social at The Mountain
Presentation (20 minutes for those who are interested) by Larry Wheeler
from The Mountain regarding its history, current happenings, future vision, and
anything that people are interested in hearing.
6:00
- 6:45 Dinner at The Mountain dining hall
7:00 Graduate Student Poster Session, Open
Discussion, and Group Social;
Graduate
Students Discussion led by Zuckerman et al.; Free beverages provided
Evening
Open for Group or Breakout Discussions as Needed
Wednesday
09 January 2002
Location:
Meeting Hall, The Mountain Retreat and Learning Center, near Highlands, NC
7:00
- 8:30 Continental Breakfast at The Mountain dining hall
8:45
Opening Remarks and Reminders;
REU
summary if a review committee was needed to prioritize the
;
"applications"
(Kloeppel)
9:00 Hazard Project Update and Summary (Pringle,
Benfield, Helfman, Meyer, et al.)
9:15
Terrestrial Gradient Project Update and Review of Data Collections
(Vose
and Kloeppel)
10:15
Coweeta Facilities Update (Kloeppel and Vose)
10:30
Break
10:45
Renewal Proposal Discussion
12:30
- 1:15 Lunch at the The Mountain dining hall
1:30 Renewal Proposal Final Discussion and Wrap-up
2:00
Working Group Research
Planning and Discussion
2:30
Meeting Adjourned
3:00
Tour of Renovated and Expanded Coweeta Analytical Lab - Jim Deal
Co-PIs
Not Attending:
Research Summaries
Co-PIs: E. Fred Benfield, J. R. Webster
The
Virginia Tech Stream Team has been working on several different projects at
Coweeta, in the southern Appalachians, and across the country. In the past year,
Jack and Fred completed a leaf breakdown project in watersheds 7 and 14 at
Coweeta. Leaf breakdown continues to be faster in streams that had been clearcut
(WS 7) than in reference streams (WS 14). Members of the Stream Team have also
been investigating carbon sources of the Little Tennessee River including both
floodplain and in-stream measurements. This research has led to two manuscripts
that are in the final stages of preparation: “The role of floods in
particulate organic matter dynamics of a southern Appalachian river/floodplain
ecosystem” (Neatrour, Webster, and Benfield) and “Metabolism along a
mid-sized southern Appalachian river” (McTammany, Webster, Benfield, and
Neatrour).
The
Stream Team has also been involved in the Coweeta Regionalization project. Matt
McTammany’s doctoral research has involved studying 30 streams that represent
a gradient of agriculture and reforestation from historical agriculture.
Dependent variables measured in his project include physical and chemical
properties, biological structure (algae, benthic macroinvertebrates), and
ecosystem function (wood breakdown and metabolism) of streams across the
southern Appalachians. Matt has completed most of his field data collection and
is in the process of analyzing data. We have also sampled fish in each of these
streams to broaden our database on the impact of land-use in structuring aquatic
communities across the region. In addition, Fred and Matt have been involved in
the Hazard Site Project investigating streams identified as likely to experience
suburbanization in the next few decades. Last spring, benthic macroinvertebrate
samples were collected from the eight hazard sites, and the samples are
currently being identified.
Jack
continues to be actively involved in several intersite research projects
including the Lotic Intersite Nitrogen Experiment (LINX), Nitrate Processing and
Retention in Streams (NPARS), and the new LINX II project. Each of these
experiments uses stable isotopes to follow the movement of nitrogen through
stream food webs and retention compartments.
Co-PI: B.D. Clinton
From 1995 – 98, Erik Nilsen, Orson Miller, and myself through funding provided by USDA CSRS-NRI, conducted a study designed to identify mechanisms associated with competition between Rhododendron maximum and other important hardwood species. A renewal was submitted in 1999 and was funded for an additional 4 years. The purpose was to further explain causes for the lack of regeneration beneath rhododendron. On the initial grant, a combination of several laboratory experiments and a field study revealed several sources of inhibition to seedling establishment in addition to low light, all of which were in the form of an apparent chemical inhibition. The most conclusive were direct and indirect mycorrhizal effects in the form of 1) decreased rates of root elongation from germinating seed (Nilsen et al. 1999), and 2) delayed mycorrhizal infection rates on woody seedling roots, respectively (Walker et al. 1999). The conclusion is that below ground interaction between rhododendron and other hardwood species may explain as much or more of the observed absence of seedling recruitment beneath rhododendron as does low light. The recently funded renewal will allow us to examine more closely the interaction between mycorrhizal species. We have added an additional dimension by including Kalmia latifolia in our studies of the role of evergreen understory in southern Appalachian forests.
Nilsen,
E.T., T.T. Lei, J.F. Walker, O.K. Miller, S.W. Semones, and B.D. Clinton. 1999.
Allelopathic potential of Rhododendron
maximum: Inhibition of seedling survival: Could allelopathy be a cause?
Amer. J. Bot. 86(11):1597-1605.
Nilsen,
E.T., B.D. Clinton, T.T. Lei, O.K. Miller, S.W. Semones, and J.F. Walker. 2001.
Does Rhododendron maximum L. (Ericaceae)
reduce the availability of resources above and belowground for canopy tree
seedlings? Am. Midl. Nat. 145:325-343.
Walker,
J.F., T.T. Lei, S.W. Semones, E.T. Nilsen, B.D. Clinton, and O.K. Miller. 1999.
Suppression of ectomycorrhizae on canopy tree seedlings in Rhododendron
maximum L. (Ericaceae) thickets in the southern Appalachians. Mycorrhiza
9:49-56.
Co-PI: D. C. Coleman
Following
up on our stated plans in the 1990 CWT renewal proposal to link upland and
aquatic processes at Coweeta, we set up study sites in the WS 55 and 56 areas,
downstream of the litter-exclusion area of Wallace, et al. Before-treatment
studies were conducted by Maxwell and Coleman (1995) and Wright and Coleman
(1999). The study site dimensions are 30m. laterally (along the stream) x 15 m.
vertically (up the slope). Our objectives were to compare effects of understory
removal of rhododendron at one site, with no extirpation at the other one. The
rhododendron removal occurred in a one-day marathon on August 29, 1995, and the
control site became a storm impacted site, receiving microbursts of up to 95
km.h-1, from Hurricane Opal, October 4-5, 1995, after rainfall
exceeding 200 mm. the preceding 24 h.
We
established transects of tension lysimeters, litterbags, and litterfall traps
and blow-through traps in both sites. The installed items in the "storm
site" were rendered obscured or broken by the uprooting of all overstory
trees, which produced several tip-up mounds. Nutrient losses to ground-water
were nearly three orders of magnitude higher in the storm slope compared to the
cut slope, reflecting the much greater pedoturbation in the former impacted site
(Yeakley et al., in revision). The biotic responses were unexpectedly small,
reflecting the insignificant changes in soil organic carbon in both sites. Soil
respiration decreased in both sites across 5 years’ time, with CO2 outputs
being significantly higher in the cut plot. Followup studies of four years of
leaf-litter decomposition and species richness of microarthropods in litter bags
set out in three transects in both sites are under way, and will be described
briefly in the January 2002 meeting.
References:
Maxwell,
R.A., and D.C. Coleman. 1995. Seasonal dynamics of nematode and microbial
biomass in soils of riparian-zone forests of the southern Appalachians. Soil
Biology & Biochemistry 27: 79-84.
Wright,
C.J., and D.C. Coleman. 1999. The effects of disturbance events on labile
phosphorus fractions and total organic phosphorus in the southern Appalachians.
Soil Science 164: 391-402.
Wright,
C.J. and D.C. Coleman. 2002. Responses of soil microbial biomass, nematode
trophic groups, N-mineralization, and litter decomposition to disturbance events
in the southern Appalachians. Soil Biology & Biochemistry 34: (in press).
Yeakley,
J. A., B. W. Argo, D. C. Coleman, J. M. Deal, B. L. Haines, B. D. Kloeppel, J.L.
Meyer, W. T. Swank and S. F. Taylor. 2002. Hillslope Nutrient Dynamics Following
Upland Riparian Vegetation Disturbance. Ecosystems, in revision.
Co PI: D.A. Crossley
Co PI: K.J. Elliott
1.
Functional diversity. Understand the functional significance
(productivity, nutrient cycling, water cycling, resistance and resilience to
disturbance) of a diverse forest stand. Develop a framework and test methods to
define ecosystem diversity from a functional viewpoint. (Jim Vose, Barry
Clinton, Jennifer Knoepp, & Brian Kloeppel are collaborators). Remove major
structural components (herb layer, shrub layer, shrub+herb layer) from mesic,
mixed-oak communities and measure changes in whole system net primary
production, and nutrient and water cycles. Permanent plots were established,
vegetation sampled, and herbaceous layer vegetation was removed in summer 1998.
Plots were resampled, herbaceous layer vegetation was removed, and a third
treatment (organic matter addition) was added to experimental design in summer
1999. -- Plot maintenance continued in summer 2000, resampled seedling transects
summer 2000. Plot maintenance May and
August 2001 (weeding, OM addition) (N-min, soil CO2, littertraps,
dendrobands continued). Plots will be maintained (weeding, addition, litter
traps) for experimental integrity growing season 2002.
2.
Watershed 7, vegetation dynamics, aboveground biomass and nutrient
accumulation. Long-term studies in succession, NPP, & nutrient dynamics of a
clearcut watershed (WS7) (Lindsay Boring and Wayne Swank, collaborators).
Resampled vegetation plots (winter 1997) and harvested trees for biomass and
nutrients by components in summer 1997. Samples were processed for dry weight,
leaf area, and nutrient content in 1998. Litter traps were collected throughout
the fall 1999- winter 2000. Litter has been sorted, weighed, and leaf mass and
LAI have been calculated, paper complete spring 2001.
Paper accepted by Canadian Journal of Forest Research. GPS permanent plots
fall-winter 2002. Resample site in 2007 (30-years succession). Chapter in
progress for WS7 Book.
3. Disturbance regimes in the Coweeta Basin. Established cooperative agreement with University of Maine, Alan S. White to use dendrochronology to understand/describe disturbance history in the Coweeta Basin, April-May 2001. Training in dendrochronology techniques Sept. 2001 at University of Maine. Disturbance History of the Coweeta Basin. Established cooperative agreement, locating plots with large/old trees for dendrochronology, recruit MS level graduate student, aid in study plan development.
Current
publications related to above projects.
Elliott, Katherine J., Stephanie Hitchcock, and Lisa Krueger. In press.
Vegetation response to large-scale disturbance in a southern Appalachian forest:
Hurricane Opal and salvage logging. Journal of the Torrey Botanical Society.
Elliott, Katherine J., Lindsay R. Boring, and Wayne T. Swank. In press.
Aboveground biomass and nutrient pools in a Southern Appalachian watershed 20
years after clearcutting. Canadian Journal of Forest Research.
Swank,
Wayne T. and Katherine J. Elliott. In preparation. Long-term patterns in forest
composition and structure following the chestnut blight. Manuscript will be
submitted to Ecology. Coweeta Basin vegetation analyses will examine the role of
chestnut; analyses and comparisons of 1934-35, 1969-73, 1988-93 vegetation
inventories (Wayne Swank, lead). Data analyses complete.
Boring,
Lindsay, Katherine J. Elliott, and Wayne T. Swank. In preparation. Vegetation
recovery: species succession, diversity, NPP, nutrient recycling, and
physiological changes. Book chapter: Deciduous Forest Ecosystem Recovery From
Cutting Disturbance in the southern Appalachians, Swank et al. (Editors). WS7
book.
Co PI: G.D. Grossman
One
of my Ph.D. students (Michael Wagner) has constructed a large, two channel
experimental stream with a programmable feeder. He has recently completed
experiments that elucidate the effects of intraspecific competition and food
availability on patch selection by two drift-feeding minnows (the native
rosyside dace and the introduced yellowfin shiner).
We
had a productive year with 6 LTER-based papers either published or in press.
These are summarized below.
We
examined the multi-scale effects of resource patchiness on foraging behavior and
habitat use by longnose dace (Thompson et al 2001). At the primary scale
(individual cobbles) foraging intensity of longnose dace was not correlated with
of benthic macroinvertebrate biomass. At the secondary scale (foraging patches),
macroinvertebrates only were patchily distributed in the summer, however, during
this season, longnose dace preferentially occupied patches with higher
macroinvertebrate biomass. At the tertiary scale (reach), benthic invertebrate
biomass was patchily distributed in all seasons and longnose dace always were
significantly more abundant in reaches with higher macroinvertebrate biomass.
Fausch
et al. (2001) examined five regions in which rainbow trout establishment varied
from highly successful (Southern Appalachians) to moderate (Colorado, &
Hokkaido Island, Japan) or failed (Honshu Island, Japan). We found that in
regions with suitable water temperatures, flood disturbance during the period of
fry emergence strongly influenced success of rainbow trout introductions. The
most successful invasions occurred in environments in which the annual
hydrologic regime closely matched that of the native habitat of rainbow trout
(i.e., Pacific Coast of North America).
We
developed a new optimal foraging model that successfully predicted habitat
selection for four drift-feeding fish species in multiple seasons and years, and
sites (one species), in Coweeta Creek (Grossman et al. 2002). The model
successfully predicted 11 of 14 cases in three seasonal samples collected over 2
years at 2 sites. Unsuccessful predictions still were within 2 cm/s of the 95%
confidence intervals of mean velocities occupied by fishes even though available
focal point velocities ranged from 0-76 to 0-128 cm/s depending on site and
season.
We
evaluated the effects of intraspecific aggression on microhabitat selection by
rosyside dace, the most abundant water-column species in Coweeta Creek (Rincon
& Grossman 2001). Rosyside dace exhibited 3 levels of aggression. The
majority of the individuals were non-aggressive (18 of 30), some were moderately
aggressive (9 of 30), and a few were highly aggressive (3 of 30). Fish size was
only weakly correlated with aggression class. All small fish were
non-aggressive, but larger fish were members of all three aggression classes.
Highly aggressive fish occupied the upstream-most position within foraging
groups and were at higher focal velocities, which may increase their access to
prey.
Grossman
et al. (2001) collected gravid female mottled sculpin (Cottus bairdi), the most abundant fish in Coweeta Creek, during
1993-1995 and again in 1998. Female sculpin matured at age 1+ although most
females did not mature until age 2+ (oldest female = 7+). Mean fecundity was 71
eggs (9-166). Female length and weight were strongly correlated with female
fecundity, although the relationship was not linear. Age had a significant but
weaker effect. Female size also significantly affected mean egg size.
We
found that female longnose dace collected during March 1999 had not yet begun
spawning whereas spawning had commenced in females collected in July 1999
(Roberts & Grossman 2001). Potential fecundity ranged from (1832 ± 572) to
(775 ± 415) oocytes per female, and was positively correlated with standard
length and somatic mass. Oocyte diameter histograms suggest that female longnose
dace potentially spawn 6+ clutches per year.
REFERENCES:
Grossman,
G.D., McDaniel, K. M., & R. E. Ratajczak. 2001. Demographic characteristics
of female mottled sculpin (Cottus bairdi) in the Coweeta Creek drainage, North
Carolina (U.S.A.). Environ. Biol. Fish.: in press (10 journal pp.).
Grossman,
G.D., Rincon, P. A., Farr, M.D., & R. E. Ratajczak. 2002. A new optimal
foraging model predicts habitat use by drift-feeding stream minnows. Ecol.
Freshwat. Fish 11: in press (10 journal pp.).
Rincon,
P.A. & G. D. Grossman. Intraspecific aggression in rosyside dace (Clinostomus
funduloides): a drift-feeding cyprinid. J. Fish Biol.: in press (19 journal
pp.).
Roberts,
J. H., & G. D. Grossman. 2001. Reproductive characteristics of female
longnose dace in the Coweeta Creek drainage (USA). Ecol. Freshwat. Fish 10:
184-190.
Co-PI: B.L. Haines
Swank,
W. T., J. Vose, and B. L. Haines. 2001 Long-term nitrogen dynamics of Coweeta
forested watersheds in the Southern Appalachians (presented as a poster, see
abstract below).
Long
term data (25 years) were analyzed for trends and dynamics of NO3 and
NH4 deposition and loss for mature mixed hardwood forest stands.
Watershed N saturation was evaluated in the context of altered N cycles and
stream inorganic N responses associated with management practices (cutting
prescriptions, species replacement and prescribed burning) and with natural
disturbances (drought and wet years, insect infestation, hurricane damage, and
ozone episodes). Reference watersheds were highly retentive of inorganic N with
deposition of < 9.9 kg ha-1 yr-1and stream water
exports below 0.25 kg ha-1 yr-1. Reference watersheds were
in transition between stage 0 and stage 1 of watershed N saturation as evidenced
by significant time trend increases in annual flow-weighted concentrations of NO3
in stream water and increases in the seasonal amplitude and duration of NO3
concentrations during 1972-1994. These stream water chemistry trends were
partially attributed to significant increases in NO3 and NH4
concentrations in bulk precipitation over the same period and/ or reduced
biological demand due to forest maturation. Evidence for stage 3 of N
saturation, where the watershed is a net source of N rather than a N Sink was
found for the most disturbed watershed at Coweeta.
Swank,
W. T., J. Vose, and B. L. Haines 2001 Long-term nitrogen dynamics of Coweeta
forested watersheds in the Southern Appalachians. (presented as a poster, see
abstract above)
Haines:
Tour leader for 27 workshop participants at Coweeta Hydrologic Laboratory on 04
November 2001. Countries represented were Chile, Canada, Peru, Ecuador,
Colombia, Costa Rica and USA
Manuscripts
submitted:
Argo,
B.W. and B.L. Haines. (submitted). Microclimate, microclimate, and flowering
phenology of Caulophyllum across an altitudinal gradient in the southern
Appalachians. Climate Research.
Argo,
B.W. and B.L. Haines. (submitted). Flowering phenology of Caulophyllum in
Southern Appalachians, USA: Application of temperature models. Canadian Journal
of Botany.
Bonito,
G.M., M.L. Cabrera, D.C. Coleman, and B.L. Haines. (submitted 25 June 2001)
Modeling the nitrogen budgets of an oak pine and northern hardwood stand.
Ecological Modeling.
Co-PI: G.S. Helfman
In LT and the FB watersheds, land use in the 1950s was a better predictor
of present-day fish diversity and occurrence than was present-day land use,
indicating that past land use activity, particularly agriculture, may result in
long-term modifications to aquatic systems, regardless of reforestation. This
"legacy effect" shows the importance of large-scale and long-term
restoration efforts; localized restoration and current efforts are unlikely to
have immediate impacts (Harding et al. 1998). A legacy effect is also evident
when comparing historical shifts in fish assemblages; current ratios of endemic
to cosmopolitan species are better explained by 1970’s land use than by
1990’s land use (Scott 2001).
Fish density and diversity are affected more by upstream than by
immediate streamside deforestation. Benthic-dependent fish species decrease in
relative abundance as non-forested patch length increases upstream. Upstream
events can overwhelm the ability of restored local riparian vegetation patches
to support stable in-stream fish habitat and assemblages (Jones et al. 1999).
As human land use practices change, upland areas of high endemism are
being invaded, displaced, and homogenized, but the initial invaders are not
foreign species but instead are native species capitalizing on habitat
degradation. The relative abundance of highland endemics is decreasing and that
of cosmopolitan species increasing as human impacts increase. Traditional
metrics of stream integrity overlook invasion by natives because (1) diversity
may initially increase with this invasion, and (2) faunal lists seldom
discriminate between upstream and downstream components. Thus the initial steps
in deterioration of stream ecosystem integrity are likely to be ignored (Scott
2001, Scott & Helfman 2001, Scott et al. submitted ms.)
Scott,
M. C. 2001. Integrating the stream and its valley: land use change, aquatic
habitat, and fish assemblages. Dissertation, Univ. of Georgia.
Scott,
M. C., and G. S. Helfman. 2001. Native invasions, homogenization, and the
mismeasure of integrity of fish assemblages. Fisheries 26 (11): 6-15.
Scott,
M. C., G. S. Helfman, M. E. McTammany, E. F. Benfield, and P. V. Bolstad.
submitted. Multiscale influences on physical and chemcial stream conditions
across southern Appalachian landscapes. Under review in J. American Water
Resources Assoc.
Co PI: M.D. Hunter
During
2001, we have focused upon two related questions in our Coweeta research:
To
answer question 1, we continue to build upon our previous work in which we
demonstrated that nutrient availability in soils and streams is influenced by
the deposition of insect frass on the forest floor. We have shown that nitrate
pulses in the soil follow insect herbivory in the canopy and that soil flora and
fauna respond positively to herbivore-derived nutrient inputs. We are expanding
this work to include experimental manipulations of potted trees as well as
continued sampling within the Coweeta basin. We are attempting to assess a)
potential changes in nutrient availability caused by root mortality, b) the
relative effects of reduced nutrient uptake and frass deposition on nutrient
availability, and c) potential feedback loops between frass-derived nitrogen and
subsequent foliage quality of trees.
To
address question 2, we have established long-term monitoring of insect
herbivores in the canopies of mature oak trees at Coweeta. Using singe-rope
techniques, we are climbing canopy trees at seven elevations within the basin,
and counting densities and diversities of insect herbivores. We are also
measuring the nutrient and phenolic chemistry of leaves and making estimates of
insect mortality. We hope to establish the relative importance of climatic
factors, nutrient availability, plant quality, and predation pressure on
densities of insects along the gradient in elevation. We have also established
experimental plots using saplings in which the exclusion of birds is crossed
with the addition of nutrients in a factorial design.
Our
ultimate goal is to understand a) the factors that influence the distribution
and abundance of herbivores in the canopy at Coweeta, b) the effects of those
herbivores on nutrient dynamics in the soil, and c) potential feedback loops
operating between the canopy and the soil mediated by herbivore activity.
Coweeta-Related Publications (last 12 months)
2002
Coleman, D.C., M.D. Hunter, J. Hutton, S. Pomeroy, & L. Swift Jr. Soil
respiration from four aggrading forested watersheds measured over a quarter
century. Forest Ecology and Management
(in press).
2001
Hunter, M.D. Multiple approaches to estimating the relative importance of
top-down and bottom-up forces on insect populations: Experiments, life tables,
and time-series analysis. Basic and
Applied Ecology 4: 293-310.
2001
Reynolds, B.C. & M.D. Hunter. Responses of soil respiration, soil nutrients,
and litter decomposition to inputs from canopy herbivores.
Soil Biology and Biogeochemistry 33: 1641-1652.
2001
Salmore, A.K. & M.D. Hunter. Environmental and genotypic influences on
alkaloid production in Sanguinaria
canadensis. Journal of Chemical
Ecology 27: 1729-1747.
2001
Salmore, A.K. & M.D. Hunter. Elevational trends in alkaloid production in Sanguinaria canadensis. Journal
of Chemical Ecology 27: 1713-1728.
2001
Hunter, M.D. Insect population dynamics meets ecosystem ecology: Effects of
herbivory on soil nutrient dynamics. Agricultural
and Forest Entomology 3: 77-84.
Co PI: B.D. Kloeppel
A)
Coweeta LTER Riparian Manuscript:
Revised
manuscript due to Ecosystems 31 January 2002
YEAKLEY,
J. ALAN, COLEMAN, DAVID C., BRUCE L. HAINES, JUDY L. MEYER, BRIAN D. KLOEPPEL,
JAMES M. DEAL, and SUSAN STEINER. Institute of Ecology, University of Georgia,
Athens, GA 30602, and Portland State University, Portland, OR. Effects of
clear-cutting understory and hurricane disturbance on hillslope-riparian
processes in the Southern Appalachians.
B)
Tree Foliar Acclimation Project:
Independently
funded grant by NSF
Cooperative
project by Bolstad, Kloeppel, Vose, et al.
Field
Data Collection Completed in fall 2001. Data summary and manuscript preparation
in 2002.
C)
International NSF Grant for Research in Poland
Manuscript in preparation
Submitted Manuscript Due 15 February 2002 to Environmental
Science and Technology
Oleksyn, J., B.D. Kloeppel, S. Lukasiwicz, and P.B.
Reich. 200_. Restoration of a degraded urban Aesculus hippocastanum site using mulching and fertilization.
Two
other projects in the data collection phase
1)
Evaluation of natural and common garden gradients in Norway spruce in the
Tatra Mountains of southern Poland and northern Slovakia (with J. Oleksyn and J.
Modrzynski)
2)
Long-term water-use efficiency and climate change in the lowland old
growth forests of the Bialowiezia National Park in eastern Poland (with A.
Korczyk and J. Oleksyn)
Co PI: J.D. Knoepp
Co PIs: S. Pearson and M. Turner
Analyses were completed on the data collected
by Norman Hicks in the late 1990s. Hicks and Pearson submitted a manuscript that
detailed findings on the response of terrestrial salamander communities to past
land uses. Contrary to expectations, we found no major differences between
salamander communities in forest stands that were previously farmed (high
intensity use) and stands that had been logged but not cleared for agriculture
(medium intensity). Stands that had not received heavy human use (low intensity)
generally had high salamander populations compared that those that had been
logged or farmed. Two undergraduates at Mars Hill College used data from this
same field effort to test for differences in abundances of wolf spiders and in
differences in the tree community among these sites. One of these students was
supported by REU funding.
Pearson
and Turner increased the scope of modeling efforts using the POPDM model, a
spatially explicit model designed to explore the effects of varying plant life
history characteristics on population persistence in fragmented landscapes. In a
related endeavor, Turner led efforts to quantify how changes in forest cover, as
documented by Bolstad and Wear, have altered the abundance and spatial pattern
of forest community types in the Southern Blue Ridge.
Three
new field projects were also started. Pearson is collaborating a colleague and
graduate student at Western Carolina University to examine differences in
breeding bird communities found in forest stands that vary in land use history
(see first paragraph above for the categories of land use history). Bird
censuses were conducted at an array of sites in the French Broad River Basin in
2001. This work will expand to sites in the Little Tenn. Basin next summer.
Pearson is also collaborating with Kitty Reynolds in monitoring avian responses
to the creation of canopy gaps in the CWT watershed. Before-treatment data were
collected this past summer. The second major field project involves measuring
soil nutrient pools and nitrogen mineralization at sites having different land
use histories. This work is being done by Jen Fratterigo, a graduate student
with Turner at UW-Madison. Jen completed a pilot project to quantify the scale
of variation with and between study plots.
Co PI: C.M. Pringle
II.
A comparison of stream and terrestrial decomposition at the Coweeta and
Luquillo LTER Sites: (Hunter/Pringle/Coleman Collaboration): The stream
portion of this project involved two graduate students: N. Powell and E.
Greathouse. The Coweeta portion of the project formed the basis of Powell’s
masters thesis which she successfully defended this year. The manuscript
resulting from her research will be submitted this year (see ‘IV-A,C’
below). Another manuscript dealing with inter-site comparisons (i.e. at Coweeta
and Luquillo) of stream decomposition is in
prep.
IV.
Products:
A.
Publications, dissertations, and theses:
(1)
Schofield, K. A., C. M. Pringle, J. L. Meyer, and A. B. Sutherland. 2001.
The importance of crayfish in the breakdown of rhododendron leaf litter.
Freshwater Biology 46: 1-14
(2)
Schofield, K. A. 2001. Top-down interactions in southern Appalachian
streams: an examination of temporal and spatial variability. Ph.D. Dissertation
, University of Georgia, Athens, GA, 251 pages.
(3)
Powell, N. L. 2001. The role of crayfish in leaf decomposition across a
range in leaf litter qualities. Masters Thesis, University of Georgia, Athens,
GA 3, 63 p.
B. Manuscripts submitted:
(1)
Schofield, L., C. M. Pringle and J. L. Meyer. Submitted. Direct
and indirect effects of increased bedload on algal and detrital based stream
foodwebs. Ecological Applications.
C. In manuscript:
(1)
Powell, N. L., C. M. Pringle, M. D. Hunter, and D. C. Coleman. The role
of crayfish in leaf decomposition across a range in leaf quality. Oecologia.
(2)
Schofield, K. A., C. M. Pringle, J. L. Meyer, E. J. Rosi, and K. D.
Kearns. Top-down interactions in a human-modified landscape: Does watershed
disturbance reduce stream macroconsumer impacts? Ecol. Appl.(?).
(3)
Schofield, K. A., C. M. Pringle and D. D. Schofield. In ms. Revisiting
the use of electricity for experimental exclusion; Past, present, and future.
Can. J. Fish Aquat. Sci.
(4) Gardiner, E.P., A. Sutherland, M.C. Scott, J.L. Meyer, G.S. Helfman, C.M. Pringle, P. V. Bolstad, and D. N. Wear. Linking stream ecosystems and landscape trajectories in the southern Appalachians. Ecol. Appl.(?).
Co-PI: B.C. Reynolds
Coweeta
LTER Research Summary
December,
2001
Reynolds,
B.C., A. Brennan, and S. Madson
Introduction
An
ongoing field of research in forest ecology is the effect of gap size on forest
dynamics. Evidence is mounting that the current “gap dynamic” model, using
gaps 30m in diameter, is insufficient to explain diversity in many forests. A
study being conducted at Coweeta by Jim Clark et al. will examine the effects of
larger gaps on the dynamics of forest stands. Our studies on soil microarthropod
communities will take advantage of the experimental gap creation to examine the
effects of different size gaps on community structure of common soil
microarthropods, taxa which are known to be integral in the decomposition of
forest litter.
Methods
Madson
and Reynolds established microarthropod sites in 3 areas which will be large
gaps ( 40 m diameter) and 2 areas which will be smaller gaps (20 m diameter).
Each site consists of 10 plots, 1 m2, along existing transects, most
within 2 m of Clark’s existing seed collectors and seedling plots.
Micrarthropod cores, 5 cm x 5 cm, are taken within each plot. Soil temperatures
are taken at half of the plots with a standard soil thermometer. Soil organic
matter determinations will be done on a subset of the cores beginning with the
November, 2001, collection. Microarthropods are sorted into the following
categories: collembola, oribatid mites, prostigmatid mites, mesostigmatid mites,
and other.
Sampling
has been done for July and November of 2000, and May, July, and November of
2001. A spring sampling is planned immediately prior to gap creation, which is
now expected to occur in April, 2002. Follow-up sampling would occur immediately
after gap creation, providing a unique data set on effects of gaps on soil
microarthropod communities (Madson, personal communication). Sampling would
continue on a seasonal basis for two years following the gap creation.
Results
Microarthropod
sorting and data analyses done by Brennan and Reynolds on soil cores collected
in July and November, 2000, indicate that seasonal differences in number of
collembola and oribatid mites are greater than differences among plots (Brennan,
Madson and Reynolds 2001). Samples from May, 2001, have been counted but the
data are yet to be analyzed.
References
Brennan,
Amanda L., Stephanie Madson, and Barbara C. Reynolds. 2001. Effects of Canopy
Gaps on Soil Microarthropod Communities. Poster for Coweeta Annual Summer
Meeting, June 2001. Athens, GA
Updates not received from the following Co-PIs:
Bolstad, Clark, Gragson, Hendrick, Meyer, Newman, Pulliam, Swank, Swift,
Vose, Wallace, Wear