15
Date 2/25/12 Effect of Tree Radiation and Snow Accumulation on Subnivean Plant Life Jane Culkin: EBIO 4100 Spring Semester 2012

Effect of Tree Radiation and Snow Accumulation on Subnivean Plant Life

Embed Size (px)

DESCRIPTION

Effect of Tree Radiation and Snow Accumulation on Subnivean Plant Life. Jane Culkin: EBIO 4100 Spring Semester 2012. Date 2/25/12. Outline of Discussion. Plants in a Winter Climate: Location Leads to Life? Question of Study Hypothesis Methods Results of Experiment - PowerPoint PPT Presentation

Citation preview

Page 1: Effect of Tree Radiation and Snow Accumulation on Subnivean Plant  Life

Date 2/25/12

Effect of Tree Radiation and Snow Accumulation on Subnivean Plant Life

Jane Culkin: EBIO 4100 Spring Semester 2012

Page 2: Effect of Tree Radiation and Snow Accumulation on Subnivean Plant  Life

Outline of Discussion

✤ Plants in a Winter Climate: Location Leads to Life?

✤ Question of Study

✤ Hypothesis

✤ Methods

✤ Results of Experiment

✤ Conclusions Based Upon Data

✤ Further Discussion

Page 3: Effect of Tree Radiation and Snow Accumulation on Subnivean Plant  Life

Plants in a Winter Climate: Location Leads to Life?

✤ What leads to more productive plant life in winter: more snow or more radiation?

✤ Both supranivean and subnivean mammals in alpine environments use various techniques to shield themselves from harsh alpine conditions.

✤ Plants too must overcome these heat loss obstacles.

✤ SCREWP

✤ refers to the six vectors, snow, cold, radiation, energy, wind, and predation that form a powerful factor that shapes the direction of evolutionary response to winter amongst all alpine organisms.

-Halfpenny 1989

-Pew and Small 2010

Page 4: Effect of Tree Radiation and Snow Accumulation on Subnivean Plant  Life

Plants in a Winter Climate: Location Leads to Life?

✤ Definition of “living plant”

✤ Many small alpine plants exist in a dormant state during winter. For the sake of this experiment I will only be referring to plants that are still photosynthesizing. i.e.: green plants

✤ These “living plants" have many heat restrictions

✤ Must be able to maintain above freezing temperatures if they are going to be able to photosynthesize efficiently

✤ functioning of plants is influenced directly and indirectly by temperature and becomes essential in determining the various strategies that have evolved to enable them to cope in heat deficient ecosystems

-Korner 2003

Page 5: Effect of Tree Radiation and Snow Accumulation on Subnivean Plant  Life

Plants in a Winter Climate: Location Leads to Life?

✤ Two General Strategies

✤ heat exchange by radiation

✤ heat conservation by limiting amount of locations that require constant heat within the body of an organism

✤ Different types of plants conduct these various techniques

✤ Mosses have evolved to have very little root systems due to the extensive amount of soil disturbance that is found on a mountain meadow

✤ Vascular plants have evolved to thrive in the sand and clay soils that contain very little nutrients near the base of a tree as oppose to the mountain valley

-Marchand 1996

-Korner 2003

Page 6: Effect of Tree Radiation and Snow Accumulation on Subnivean Plant  Life

Question of Study

✤ The location of plant life, more so than animal life in many regards, determines the survival rate of the species because plant life does not have the ability to move locations as easily as an animal.

✤ Research Question: When looking at subnivean plant life in subalpine locations, which plants will respond better to winter conditions, those under snow in an open field or those under the protection of an aspen tree? Which manner is more conducive to heat and energy storage?

Page 7: Effect of Tree Radiation and Snow Accumulation on Subnivean Plant  Life

Hypothesis

✤ My hypothesis, given other research on alpine plants, is that plants that grow near a tree will tend to be larger and more structured than those that grow in an open meadow for they are less exposed to the harsh winter climate due to both the trees’ radiation as well as the covering that the tree provides via its branches.

Page 8: Effect of Tree Radiation and Snow Accumulation on Subnivean Plant  Life

Methods

✤ Structure of Experiment

✤ plant life in three different locations

✤ four plots under aspen trees and one plot in an open meadow

✤ Each plot had a radius of 60.96 centimeters

✤ two trees were located relatively close to the meadow

✤ two trees were located near a river bed to see if there would be a difference between the plant life found in the two aspen locations

Page 9: Effect of Tree Radiation and Snow Accumulation on Subnivean Plant  Life

Methods

✤ Took the air temperature

✤ Took snow temperature every 15 centimeters from the outer rim of the plot up to the tree or center of the plot, in the case of the meadow.

✤ repeated exercise for snow depth and ground temperature

✤ done on both the Northern and Southern side of the tree

Page 10: Effect of Tree Radiation and Snow Accumulation on Subnivean Plant  Life

Results from Experiment

Regression of Temperature of Ground: Tree Two

Distance From Tree (inches)

Tem

pera

ture

°C

--

-- P Value: 0.0004

R2: 0.991

Distance From Tree (inches)

Tem

pera

ture

°C

Regression of Temperature of Ground: Tree One

--

--

-

P Value:0.169R2: 0.521

P Value:.03126P Value:.03126

Tem

pera

ture

°C

Distance South to North in

Meadow(inches)

Regression of Temperature of Ground: Meadow

--

--

- P Value:0.3189R2: 0.321

Page 11: Effect of Tree Radiation and Snow Accumulation on Subnivean Plant  Life

Results from ExperimentDepth of Snow to

Plant Life

Depth of Snow(inches)

Am

ou

nt o

f pla

nt life

(# o

f living

org

an

isms in

60

.96

ce

ntim

ete

r are

a)

Linear Regression of Ground Temperatures

Tem

pera

ture

°C

Distance from Tree (inches)

Meadow

Tree 2

Tree 3

-

-

-

-

-

P Value:.03126R2: .8306

Page 12: Effect of Tree Radiation and Snow Accumulation on Subnivean Plant  Life

Trends in Data✤ Inconclusive temperature results on the ground

✤ tree two had a strong R2 value however, other temperature regressions were not as correlated

✤ Found significant change in types of snow in all aspen and meadow locations

✤ tree one and two had semi frozen ground where as tree three and tree four had moist ground with slight faceting at the bottom of the snow pack but predominantly rounded snow throughout the rest of the pack.

✤ very strong R2 value for snow depth to amount of plant life

Page 13: Effect of Tree Radiation and Snow Accumulation on Subnivean Plant  Life

Conclusion

✤ Trends in snow depth as well as the inconclusive temperatures of the ground display that my hypothesis was incorrect. The radiation of a tree does not drastically affect plant life.

✤ Depth of snow and moisture content of snow pack plays a larger role in determining the survival rate of non dormant plants in the winter.

✤ Tree three and four were both located next to a stream bed and both contained the largest amount of green plant life which would suggest that the moisture content was larger in those areas and thus the plants had the nutrients that they needed to survive in the winter. Trees one and two, as well as the meadow, did not have access to these resources and thus could not survive as well.

Page 14: Effect of Tree Radiation and Snow Accumulation on Subnivean Plant  Life

Further Discussion

✤ New Research Question: How does water, in the form of runoff or a stream bed, effect the plant life that is able to remain in a non dormant state throughout winter?

Page 15: Effect of Tree Radiation and Snow Accumulation on Subnivean Plant  Life

Sources

✤ Korner, C. 2003. Alpine plant life : functional plant ecology of high mountain ecosystems. Berlin/New York: Springer.

✤ Halfpenny, James C. "Life,Winter, and Adaptation." Winter: An Ecological Handbook. Boulder: Johnson, 1989. 66-68.

✤ Marchand, Peter J. "Life Under Ice." Life in the Cold: An Introduction to Winter Ecology. 3rd ed. Hanover: University of New England, 1996. 153-58.

✤ Pugh, Evan, and Eric Small. "Hydrologic Sciences Student Research Symposium." CU Boulder Hydrologic Studies: Quantitative Studies in Water in the Environment. CU Boulder Hydrologic Studies. <http://hydrosciences.colorado.edu/>.