1) The study examined how stream carbon loss through leaf litter breakdown rates may be affected by warming temperatures using data from Coweeta Basin streams and Athens, Georgia streams.
2) Leaf packs were deployed in streams along a temperature gradient and breakdown rates were compared to predictions from the metabolic theory of ecology.
3) Preliminary results found relationships between faster breakdown rates and higher temperatures, though slopes were generally steeper than predicted, and variability was high. Including more disturbed Athens streams lessened the temperature effect relationship.
Influence of Climatic Factors on the Δ13c Values of the C3, C4 And CAM Dicot ...QUESTJOURNAL
ABSTRACT: Species of the Centrospermeae occurring at different altitudes were analyzed for δ13C values and assigned for graphical representation. The aridity of the study area was evident as defined using the Klimadiagramm. Climatic data was studied and represented on graphs for interpretation. The frequency ofδ 13C values of the species at different altitudes, namely 500m a.s.l., 1000m a.s.l., 1500m a.s.l., 2000m a.s.l., 2500m a.s.l., 3000m a.s.l., 3500m a.s.l. and 4000m a.s.l., are presented on graphs. The data show thatδ13C values is a good predictor of spatial diversity and shift of the species along the altitudinal gradient of environmental factors.There is phenomenal trend such that δ13C values distribution along altitudinal differentiation the values of -10.60‰, to -16.65‰, -17.75‰ to -18.87‰, and -18.89‰ to -32.42‰ correspond to the species at low altitudes (0m a.s.l. – 1500m a.s.l.), intermediate altitude (1,550m a.s.l.-1,700m a.s.l.) and high altitude (1,800m a.s.l. – 4200m a.s.l.0, respectively. The inverse correlation between temperature and rainfall defines the causal climatic factors affecting C3 and C4 species along the altitudinal gradient. The occurrence of the transition zone between temperature and rainfall mirror that between the relative abundance of the C3 and C4 species along the altitude. This floristic data predict NAD-ME, NADP-ME AND PEP-CK types of monocot-dicot transition along the altitude with respect to bioproductivity in the tropics.
Using linear stability theory, the effects of temperature gradient and first-order chemical reaction on the onset of Rayleigh-Benard convection in CO2 sequestration in the isotropic porous medium within Eastern Niger-Delta region, Nigeria is theoretically investigated. A simplified model is envisaged for the interactive relationship between carbon dioxide and ambient brine in deep underground aquifers; the instability which is a favorable process for CO2 sequestration considering the fact that it accelerates dissolution and mixing of CO2 hence, reducing the time needed to safely store CO2 in the aquifer. Analytical expressions for the critical Rayleigh number and their corresponding wave numbers for the onset of stationary convections are determined using linear stability analysis. The time scale for the onset of convection as indicated by diverse linear stability analyses of the short-term base state may be long (for years) but virtually will without a doubt, be notably shortened by mixing during injection of supercritical CO2. The key purpose of this paper is to explore the role porous media isotropy plays in the onset of convective instability of sequestered CO2 in the underground aquifer. It is shown that for changes in permeability in the isotropic porous medium, the onset of instability in the stationary convection mode is experienced faster in areas of higher permeability than in areas of lower permeability regions were the onset of instability in the stationary convection mode experiences a delay, making areas with low permeability in the isotropic medium not suitable for convective instability of sequestered CO2 probably because the rocks lack fractures and high level of compaction is present. It is also observed that the ratio of thermal diffusivity to mass diffusivity (the Lewis Number), lower values of the Damköhler number and the presence of the Solute Rayleigh number, delays the onset of instability of sequestered CO2 in the system in the isotropic porous medium. However, interestingly, at a high solute reaction rate to diffusion rate (increasing Damköhler number from to ), a change in permeability of the porous medium does have a pronounced effect on instability in the isotropic porous medium were the onset of instability is delayed in low permeability region but on the contrary is enhanced/facilitated in higher permeability region.
Effect of Temperature on Stream Fish Energetics and Tolerance to Increasing U...Marylou Moore
ABSTRACT
Urban development threatens stream systems throughout the world and has been shown to correspond with predictable changes in fish assemblage attributes. These shifts in fish communities suggests that there may be species specific differences in tolerance to altered environmental conditions related to urbanization. Over the last three decades, a great amount of literature has focused on the development of community-level metrics for assessing biotic integrity of fishes within flowing waters. While these efforts have spawned a great deal of information on community and guild-level responses by stream fishes, it is unknown how individual species’ evolutionary adaptation and physiological acclimation correspond to their ability to tolerate drastic environmental change. This study investigated temperature-dependent responses of metabolism and thermal sensitivity in redbreast sunfish (Lepomis auritus) collected from sites representative of the lowest and highest degree of urban land use throughout the Etowah Watershed, Georgia. Standard metabolic rate (SMR) was shown to be significantly lower in fish drawn from the urban stream at both experimental temperatures (20 °C and 25 °C). Additionally, the urban population had a significantly higher metabolic scope at 25 °C than the non-urban population. These findings support the hypothesis that intraspecific differences in thermal tolerance may exist at localized scales within a small watershed. This study also provides the first known reports of the metabolic rate and aerobic scope of L. auritus.
Statistical Laboratory Report Analysis of 3 Datasets
1-Oxygen concentration changes in marine seagrass ( zostera) related to an increase of time factor in saltwater in Australia
2-Trends in cigarettes consumption during weekdays among British male smokers
3-The differences in concentration of Silica dioxide in rocks from Kilauea volcanoes and rocks from whole Hawaiian volcanoes
Influence of Climatic Factors on the Δ13c Values of the C3, C4 And CAM Dicot ...QUESTJOURNAL
ABSTRACT: Species of the Centrospermeae occurring at different altitudes were analyzed for δ13C values and assigned for graphical representation. The aridity of the study area was evident as defined using the Klimadiagramm. Climatic data was studied and represented on graphs for interpretation. The frequency ofδ 13C values of the species at different altitudes, namely 500m a.s.l., 1000m a.s.l., 1500m a.s.l., 2000m a.s.l., 2500m a.s.l., 3000m a.s.l., 3500m a.s.l. and 4000m a.s.l., are presented on graphs. The data show thatδ13C values is a good predictor of spatial diversity and shift of the species along the altitudinal gradient of environmental factors.There is phenomenal trend such that δ13C values distribution along altitudinal differentiation the values of -10.60‰, to -16.65‰, -17.75‰ to -18.87‰, and -18.89‰ to -32.42‰ correspond to the species at low altitudes (0m a.s.l. – 1500m a.s.l.), intermediate altitude (1,550m a.s.l.-1,700m a.s.l.) and high altitude (1,800m a.s.l. – 4200m a.s.l.0, respectively. The inverse correlation between temperature and rainfall defines the causal climatic factors affecting C3 and C4 species along the altitudinal gradient. The occurrence of the transition zone between temperature and rainfall mirror that between the relative abundance of the C3 and C4 species along the altitude. This floristic data predict NAD-ME, NADP-ME AND PEP-CK types of monocot-dicot transition along the altitude with respect to bioproductivity in the tropics.
Using linear stability theory, the effects of temperature gradient and first-order chemical reaction on the onset of Rayleigh-Benard convection in CO2 sequestration in the isotropic porous medium within Eastern Niger-Delta region, Nigeria is theoretically investigated. A simplified model is envisaged for the interactive relationship between carbon dioxide and ambient brine in deep underground aquifers; the instability which is a favorable process for CO2 sequestration considering the fact that it accelerates dissolution and mixing of CO2 hence, reducing the time needed to safely store CO2 in the aquifer. Analytical expressions for the critical Rayleigh number and their corresponding wave numbers for the onset of stationary convections are determined using linear stability analysis. The time scale for the onset of convection as indicated by diverse linear stability analyses of the short-term base state may be long (for years) but virtually will without a doubt, be notably shortened by mixing during injection of supercritical CO2. The key purpose of this paper is to explore the role porous media isotropy plays in the onset of convective instability of sequestered CO2 in the underground aquifer. It is shown that for changes in permeability in the isotropic porous medium, the onset of instability in the stationary convection mode is experienced faster in areas of higher permeability than in areas of lower permeability regions were the onset of instability in the stationary convection mode experiences a delay, making areas with low permeability in the isotropic medium not suitable for convective instability of sequestered CO2 probably because the rocks lack fractures and high level of compaction is present. It is also observed that the ratio of thermal diffusivity to mass diffusivity (the Lewis Number), lower values of the Damköhler number and the presence of the Solute Rayleigh number, delays the onset of instability of sequestered CO2 in the system in the isotropic porous medium. However, interestingly, at a high solute reaction rate to diffusion rate (increasing Damköhler number from to ), a change in permeability of the porous medium does have a pronounced effect on instability in the isotropic porous medium were the onset of instability is delayed in low permeability region but on the contrary is enhanced/facilitated in higher permeability region.
Effect of Temperature on Stream Fish Energetics and Tolerance to Increasing U...Marylou Moore
ABSTRACT
Urban development threatens stream systems throughout the world and has been shown to correspond with predictable changes in fish assemblage attributes. These shifts in fish communities suggests that there may be species specific differences in tolerance to altered environmental conditions related to urbanization. Over the last three decades, a great amount of literature has focused on the development of community-level metrics for assessing biotic integrity of fishes within flowing waters. While these efforts have spawned a great deal of information on community and guild-level responses by stream fishes, it is unknown how individual species’ evolutionary adaptation and physiological acclimation correspond to their ability to tolerate drastic environmental change. This study investigated temperature-dependent responses of metabolism and thermal sensitivity in redbreast sunfish (Lepomis auritus) collected from sites representative of the lowest and highest degree of urban land use throughout the Etowah Watershed, Georgia. Standard metabolic rate (SMR) was shown to be significantly lower in fish drawn from the urban stream at both experimental temperatures (20 °C and 25 °C). Additionally, the urban population had a significantly higher metabolic scope at 25 °C than the non-urban population. These findings support the hypothesis that intraspecific differences in thermal tolerance may exist at localized scales within a small watershed. This study also provides the first known reports of the metabolic rate and aerobic scope of L. auritus.
Statistical Laboratory Report Analysis of 3 Datasets
1-Oxygen concentration changes in marine seagrass ( zostera) related to an increase of time factor in saltwater in Australia
2-Trends in cigarettes consumption during weekdays among British male smokers
3-The differences in concentration of Silica dioxide in rocks from Kilauea volcanoes and rocks from whole Hawaiian volcanoes
Another recent upload to my website of work regarding monitored plume stability and monitored natural attenuation at creosote and coal tar DNAPL sites, including many Beazer sites.
Dr. Jack Morgan - Grazinglands and Global Climate Change: What is the Science...John Blue
Grazinglands and Global Climate Change: What is the Science Telling Us? - Dr. Jack Morgan, USDA/ARS, from the 2012 Annual Conference of the National Institute for Animal Agriculture, March 26 - 29, Denver, CO, USA.
More presentations at: http://www.trufflemedia.com/agmedia/conference/2012-decreasing-resources-increasing-regulation-advance-animal-agriculture
Strong variance at decadal and multidecadal timescales is a common feature of most tree-ring width records. But does this aspect of tree growth exhibit such long-memory behavior due to biology, climate, or some combination of the two factors? Understanding the origins of this behavior is crucial for efforts to evaluate the causes of decadal variability in the climate system.
Presentation at Johann Gutenburg University (Mainz) on February 16, 2017.
Guarding against false discovery in large-scale dendroclimatologyScott St. George
Measurements of tree-ring widths are the most widely-distributed and best replicated source of surrogate environmental information on the planet, and are one of the main archives used to estimate changes in regional and global climate during the past several centuries or millennia. Because the Northern Hemisphere ring-width network is now so large, it is more crucial than ever to ensure our understanding of tree-environment relations is not influenced by decisions to include or exclude certain records. It may be the case that a particular set of ring-width records are, for whatever reason, more tightly coupled to a particular climate factor than other records from the same region or species and, as a result, may be superior estimators of that factor’s past behavior. At the same time, it is known that selecting a small number of predictors from a large pool of potential candidates increases the likelihood of a Type I error. That effect may be particularly relevant to dendroclimatology because the total number of available ring-width records is often much larger than the number of records used to produce reconstructions of large-scale climate features. As an initial step, it would be helpful if paleoclimate reconstructions derived from tree rings described more explicitly the criteria used to select ring-width records as potential predictors and specified those records excluded by that screening. By comparing ring-width chronologies and their relations with climate against the standard set by thousands of records across the hemisphere, we should be better able to distinguish climate signals from proxy noise and produce more accurate reconstructions of climate during the late Holocene.
Another recent upload to my website of work regarding monitored plume stability and monitored natural attenuation at creosote and coal tar DNAPL sites, including many Beazer sites.
Dr. Jack Morgan - Grazinglands and Global Climate Change: What is the Science...John Blue
Grazinglands and Global Climate Change: What is the Science Telling Us? - Dr. Jack Morgan, USDA/ARS, from the 2012 Annual Conference of the National Institute for Animal Agriculture, March 26 - 29, Denver, CO, USA.
More presentations at: http://www.trufflemedia.com/agmedia/conference/2012-decreasing-resources-increasing-regulation-advance-animal-agriculture
Strong variance at decadal and multidecadal timescales is a common feature of most tree-ring width records. But does this aspect of tree growth exhibit such long-memory behavior due to biology, climate, or some combination of the two factors? Understanding the origins of this behavior is crucial for efforts to evaluate the causes of decadal variability in the climate system.
Presentation at Johann Gutenburg University (Mainz) on February 16, 2017.
Guarding against false discovery in large-scale dendroclimatologyScott St. George
Measurements of tree-ring widths are the most widely-distributed and best replicated source of surrogate environmental information on the planet, and are one of the main archives used to estimate changes in regional and global climate during the past several centuries or millennia. Because the Northern Hemisphere ring-width network is now so large, it is more crucial than ever to ensure our understanding of tree-environment relations is not influenced by decisions to include or exclude certain records. It may be the case that a particular set of ring-width records are, for whatever reason, more tightly coupled to a particular climate factor than other records from the same region or species and, as a result, may be superior estimators of that factor’s past behavior. At the same time, it is known that selecting a small number of predictors from a large pool of potential candidates increases the likelihood of a Type I error. That effect may be particularly relevant to dendroclimatology because the total number of available ring-width records is often much larger than the number of records used to produce reconstructions of large-scale climate features. As an initial step, it would be helpful if paleoclimate reconstructions derived from tree rings described more explicitly the criteria used to select ring-width records as potential predictors and specified those records excluded by that screening. By comparing ring-width chronologies and their relations with climate against the standard set by thousands of records across the hemisphere, we should be better able to distinguish climate signals from proxy noise and produce more accurate reconstructions of climate during the late Holocene.
Conference abstract for the Goldschmidt Conference, held in Knoxville, Tennessee, in 2010. Authors: myself, Dr. Bernhard Peucker-Ehrenbrink at Woods Hole Oceanographic Institution, and Paul Hoffman of snowballearth.org.
http://goldschmidtabstracts.info/2010/1117.pdf
impactos del cambio climatico en ecosistemas costerosXin San
Anthropogenically induced global climate change has profound implications for marine
ecosystems and the economic and social systems that depend upon them. The
relationship between temperature and individual performance is reasonably well
understood, and much climate-related research has focused on potential shifts in
distribution and abundance driven directly by temperature. However, recent work has
revealed that both abiotic changes and biological responses in the ocean will be
substantially more complex. For example, changes in ocean chemistry may be more
important than changes in temperature for the performance and survival of many
organisms. Ocean circulation, which drives larval transport, will also change, with
important consequences for population dynamics. Furthermore, climatic impacts on one
or a few leverage species may result in sweeping community-level changes. Finally,
synergistic effects between climate and other anthropogenic variables, particularly fishing
pressure, will likely exacerbate climate-induced changes. Efforts to manage and conserve
living marine systems in the face of climate change will require improvements to the
existing predictive framework. Key directions for future research include identifying key
demographic transitions that influence population dynamics, predicting changes in the
community-level impacts of ecologically dominant species, incorporating populations
ability to evolve (adapt), and understanding the scales over which climate will change and
living systems will respond.
Biomass partitioning, leaf area index, and canopy greenness: the Good, the BA...remkoduursma
Seminar presented to the Hawkesbury Institute for the Environment's weekly seminar series on 28 October 2015. Topics include a global database of plant biomass and allometry, leaf area index at the EucFACE, and canopy greenness as measured with phenocams.
LAB NAME3Lab Number ____Your NameProfe.docxsmile790243
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CLIMATE CHANGE
Body shrinkage due to Arctic
warming reduces red knot fitness in
tropical wintering range
Jan A. van Gils,1* Simeon Lisovski,2 Tamar Lok,3,4 Włodzimierz Meissner,5
Agnieszka Ożarowska,5 Jimmy de Fouw,1 Eldar Rakhimberdiev,1,6 Mikhail Y. Soloviev,6
Theunis Piersma,1,3 Marcel Klaassen2
Reductions in body size are increasingly being identified as a response to climate
warming. Here we present evidence for a case of such body shrinkage, potentially due
to malnutrition in early life. We show that an avian long-distance migrant (red knot,
Calidris canutus canutus), which is experiencing globally unrivaled warming rates at its
high-Arctic breeding grounds, produces smaller offspring with shorter bills during
summers with early snowmelt. This has consequences half a world away at their tropical
wintering grounds, where shorter-billed individuals have reduced survival rates. This is
associated with these molluscivores eating fewer deeply buried bivalve prey and more
shallowly buried seagrass rhizomes. We suggest that seasonal migrants can experience
reduced fitness at one end of their range as a result of a changing climate at the
other end.
P
henological changes andgeographicalrange
shifts are well-known responses to climate
change(1).Athirdbroadlyobservedresponse
to global warming appears to be shrinkage
of bodies (2–5). It has been hypothesized
that body shrinkage is a geneticmicroevolutionary
response to warming, due to smaller individuals
being better able to dissipate body heat because
of the larger surface/volume ratio of their bodies
[e.g., Bergmann’s rule (2)]. Alternatively, ithas been
putforwardthatclimatechangemaydisrupttroph-
ic interactions, potentially leading to malnutrition
during an organism’s juvenile life stage (6, 7). Be-
cause poor growth may not be compensated for
later in life (8), this would lead to smaller bodies
(i.e., shrinkage as a phenotypically plastic response).
Under climate change, some regions are warm-
ing faster than others. Especially in the Arctic,
warminghas been observedat unprecedentedr ...
Similar to Frandson Coweeta LTER Summer Symposium poster (20)
1. PREDICTING WARMING EFFECTS ON STREAM CARBON LOSS
USING LITTER BREAKDOWN RATES FROM THE COWEETA BASIN
Garrett Frandson1,2, Phillip Bumpers1, Amy Rosemond1, Seth Wenger1 , and Morgan Bettcher1
1Odum School of Ecology, University of Georgia, Athens, GA 30602
2Coweeta 2016 summer REU student, University of Central Arkansas, Conway, AR 72032
BACKGROUND
METHODS
ACKNOWLEDGEMENTS
DISCUSSION
REFERENCES
NSF Research Experience for Undergraduates awarded through
the Coweeta LTER program. Thanks to Kait Farrell, Chao Song,
and David Manning for aid in statistical analyses and
interpretations.
1. Wallace, J.B.; Eggert, S.L.; Meyer, J.L.; and Webster, J.R. (1997). Multiple
trophic levels of a forest stream linked to terrestrial litter inputs. Science. 277,
102-104.
2. Boyero et al. (2001). A global experiment suggests climate warming will not
accelerate litter decomposition in streams but might reduce carbon
sequestration. Ecology Letters. 14, 289-294.
3. Benstead, J.P. and Huryn, A.D. (2011). Extreme seasonality of litter
breakdown in an arctic spring-fed stream is driven by shredder phenology, not
temperature. Freshwater Biology. 56, 2034-2044.
4. Hieber, M. and Gessner, M.O. (2002). Contribution of stream detrivores, fungi,
and bacteria to leaf breakdown based on biomass estimates. Ecology. 83(4),
1026-1038.
5. Brown, J.H. et al. (2004). Toward a metabolic theory of ecology. Ecology.
85(7), 1771-1789.
6. Benfield, E.F. (2007). Decomposition of leaf material. Pp. 711-720. In: Hauer
and Lamberti (Ed.s) Methods in Stream Ecology, Academic Press.
RESULTS
STUDY SITE
HYPOTHESES
• The slope the log of breakdown rate as a function of inverse
temperature (1/kT where k is Boltzmann’s constant and T is in
Kelvin) should align with the activation energy’s range of values
(0.6-0.7 eV5) predicted by the MTE.
• Shredder breakdown rates will decrease with increasing water
temperature due to being cold-adapted and temperature-sensitive
organisms2.
• Microbial breakdown rates will increase with increasing water
temperatures as the additional heat drives faster enzymatic
activity5.
• Decomposition rates will be higher in Acer samples than in
Rhododendron samples due to Rhododendron leaves being of
tougher structure.
• Stream water temperatures are predicted to increase with
predicted trends in land use and air temperature increases.
• Headwater streams are crucial to aquatic ecosystems and the
global carbon cycle due to their processing of terrestrial carbon
inputs, primarily leaf litter, and their transport of foodweb-
supporting carbon to downstream systems1,2. Understanding the
effects of increasing stream water temperatures is thus crucial to
understanding large-scale ecosystem effects of climate change.
• The biological decomposition of leaf litter in streams is due to
shredding macroinvertebrates, fungi, and bacteria with the
macroinvertebrates and fungi contributing most3,4.
• The metabolic theory of ecology (MTE) may be used to make
predictions about the relationship between temperature and the
rates of many biological processes5, here specifically litter
breakdown.
• Examining leaf litter processing rates along a gradient of
temperature caused by seasonal progression and differences in
elevation, aspect, and shade should provide insight into expected
aquatic carbon processing responses to increasing stream water
temperatures.
Stream Mean Water Temperature (°C)
1: Albert Branch 15.81
2: Pinnacle Branch 15.84
3: Bee Branch 15.98
4: Big Hurricane Branch 16.28
5: Shope Branch 16.77
6: Copper Branch 16.41
7: Shope Fork (Forest) 17.22
8: Shope Fork (Gap) 17.24
9: Carpenter Branch 16.96
10: Sawmill Branch 17.99
11: Hugh White Creek 17.47
12: Upper Ball Creek 15.79
Athens: Tallassee Creek 23.09
Athens: Turkey Creek 23.07
Athens: Brooklyn Creek 22.16
Athens: Brickyard Creek 23.84
• Leaf packs consisting of 5.0 ± 0.1 grams of a fast-decaying (Acer
rubrum) or a slow-decaying (Rhododendron maximum) species
were deployed at 12 sites at the Coweeta Hydrologic Laboratory.
Two deployments were made, 4 replicate packs per site. Onset
HOBO Pendant water temperature and lux recorders were also
deployed with each leaf pack set on June 6, 2016. We contrasted
the response of breakdown with coarse mesh (including
invertebrates) and fine mesh (microbial breakdown only).
• The process was also conducted once with Acer leaves in four
streams in Athens, Georgia.
• Leaf packs were
retrieved approximately
six weeks after
deployment, and
recorders’ data were
downloaded. Packs
were kept on ice until
laboratory processing.
• Leaf packs were
processed and ash-free
• The expected negative relationship between temperature and
breakdown rate was at least suggested as a trend in all three
comparisons.
• The negative relationship and trends between 1/kT and
ln (breakdown rate) are equivalent to positive relationships and
trends between temperature and breakdown rate and
represented more than a doubling of breakdown rate across
Coweeta streams across a gradient of ~2oC.
• Rhododendron breakdown was slower than Acer but responses
to temperature were similar between the two species.
• There was a positive relationship between 1/kT and ln
(breakdown rate) for the coarse Acer leaves of deployment A but
not B. This was potentially due to the bags of deployment A
experiencing more burials which may lead to less colonization
and lower breakdown rates. Notably, three of the streams’ bags
with the lowest breakdown rates also had heavy burials.
Macroinvertebrate data was collected from only deployment A,
thus these burials confounded shredder response analysis.
Implications and next steps
• Steeper slopes in the relationships between breakdown and
temperature indicate greater effects on breakdown rates than
would predicted from MTE. Both our empirical data and MTE
predict faster losses of carbon via breakdown with increased
temperature.
• In our study, relatively high variability in breakdown rates resulted
in large confidence intervals; additional data (seasonal) will be
collected in the future to attempt to more accurately predict
temperature effects on breakdown.
• The contrast with streams in a more disturbed environment
(Athens, GA) gives insights into other aspects of temperature
effects. Slopes between breakdown and temperature were less
steep with inclusion of Athens data – indicating potentially
suppressed biological activity in disturbed streams.
• Future work may extend the duration of the study, increase the
number of bags in a deployment, capture and incorporate
dissolved nutrient and contaminant data, and deploy bags such
that depositional burials are less common.
Subset Slope
Figure
Intercept
Overall
Model’s
𝐑 𝟐
Figure
1
C. A.
-2.085
-3.673
0.363
C. R. -4.888
Figure
2
F. A.
-1.366
-4.315
0.459
F. R. -4.4842
Figure
3
C. A.
-0.512
-3.646
0.211
F. A. -4.096
Figure 2. The log of fine mesh breakdown rate against 1/kT
showed no significant relationship but a negative trend with
p=0.080. There was a significant effect of litter species on
breakdown rate. Slope is less steep (-1.37) than coarse mesh
but also steeper than MTE prediction; the 95% confidence
interval is large (-2.913 to 0.180).
Figure 3. We used sites in Athens, GA to extend the
temperature and in-stream condition range of our data. The log
of breakdown rate against 1/kT was statistically significant
(p=0.022); the slope (-0.51) was less steep than MTE prediction.
There was a significant effect of mesh size on breakdown rate.
Table 1 : Summary table of values for Figures 1-3. The
subsets are, respectively, coarse Acer, coarse
Rhododendron, fine Acer, fine Rhododendron, coarse
Acer, and fine Acer.
Figure 1. The log of coarse mesh breakdown rate plotted
against 1/kT showed no significant relationship but a trend
with p=0.077. There was a significant effect of litter species
on breakdown rate. Slope is steeper (-2.08) than MTE
prediction, (ca. -0.6); the 95% confidence interval is large
(-4.414 to 0.244).
dry mass calculations were done as per
standard methods6.
• Slopes between breakdown and temperature were compared to the
linear Arrhenius equation to assess whether empirical data matched
predictions from MTE.
Coweeta – Total breakdown Coweeta – Microbial breakdown
Coweeta – Athens
Total, microbial breakdown