Locating Temperature In Mobile, AL Using Leaf Analysis Formula

Brittany Beach

AbstractThe leaves on each plant of a tree are specific. They can define a plant’s temperature. By using the formula AAT= (smooth-edged leaves %)(0.3006) + 1.141, one will find the data of average temperature to woody dicots around their areas. The class collected leaves where we categorized the leaves according to whether they have teeth or smooth-edged leaves on their outer rim. We calculated the data by using simple mathematics to find the percentage of smooth-edged leaves that helped to determine the average temperature in Mobile, AL using the formula above. The data from the formula indicated a temperature average of 68.4OF, showing an Internet result of 67.5OF in Mobile as the average annual temperature. The results lead me to question whether Colorado, which has strong winds, would probably have a few smooth-edged leaves but would it be a result of weather or wind. Recently, there was a tornado; just how much data would be accurate in the West. Is it easier to analyze data in areas that are hotter?

Introduction

Leaves come in all different shapes and sizes. There is more to a leaf than the stem, node, or its veins. Some leaves are harmful for you like poison ivy and others are good for you. A leaf’s physical appearance can tell you a lot about its environment. The leaves have different edges. Some are

smoothed (Fig. 1A) and they are smoothed-edge leaves and the others look like teeth (Fig. 1B) and they are referred to as teeth-edged leaves. As we learned more about these two different types of distinct leaves, we wanted to predict the temperature of the

leaves by the data we collected, using this formula:The formula would then compute the data to show the average temperature range shown in Celsius. Our class hypothesized that 68.4O

F would be the average temperature of Mobile, AL.

Materials & MethodsThe students in the class were asked to bring at least two woody dicots from their homes, around campus, and other areas around Mobile, AL. The woody dicots were then sorted into their correct categories of having teeth or being smooth edged on their leaves. Professor Axsmith asked the class to review the leaves categories to make sure there was not any leaves that would be indicate the data was inaccurate and would lead to

1

FIGURE 1. (A) Leaves of Modern Plants with Smooth (‘ENTIRE’) margins. (B) Leavs of Modern Plants with Toothed margins. Credit: L. Seyfullah.

2 TEMPERATURE AND LEAF ANALYSIS FORMULA

inconclusive results. Then, he asked us to pair the leaves of each category that were similar types together as best as we could. Finally, we calculated that there were a total of 63 woody dicots brought in. A part of that number was 40 smooth-edged leaves and 23 teeth-edged leaves. We calculated the percentage of smooth leaves by 40 smooth-edged/63 total= 63.49 %. Given the formula to calculate the average annual temperature (AAT):

The values were inputted to calculate the AAT. The AAT is the estimated temperature in Celsius. To convert the temperature 20.23OC from Celsius to Fahrenheit:

Results

Sample# Smooth

# Teeth# Total

% Smooth

OC OF

Predicted AAT for Mobile, AL:

40 23 63 63.4920.23

68.4

Known AAT for Mobile, AL:

N/A N/A N/A N/A 19.7 67.5

Upon the research on the Internet, we found the average temperature in Mobile, AL was about 67.5OF1. Therefore, we accept the

hypothesis that the 68.4OF was the average temperature of Mobile, AL.

DiscussionThe results show a .9 difference of correlation between our data and the research data for Mobile, AL. Since the hypothesis was accepted, I would gather that Royer and Wilf2 were correct about the warmer temperatures showing more smoothed-edged leaves. The teeth are a result of teeth enhancing plant growth at the beginning of the growing season when temperatures are limiting. The teeth boost transpiration and photosynthate production early in the growing season, maximizing carbon gain when temperature is limiting. This helps explain the core observation underlying most paleoclimate estimates based on fossil leaf teeth (Royer & Wilf, 2006). This leaves me to wonder if the weather in Colorado would show a different result. They would have many teethed leaves however the average temperature of Colorado jumps around monthly. Last year, there were negative temperatures for the first time in several years and I would imagine with the snow, predicting the average temperature would be challenging as well as with the floods that often occur. However in Royer and Wilf’s article, the colder a climate the more teeth-edged leaves in that region or area. According3, the average temperature in Aurora, CO is 50.8OF. If I were to go home and collect leaves from Aurora, I would likely get a mix of leaves since the winds are heavy at what they refer to as Mile High. It is possible I have a good number of leaves but the leaves that I had traveled from the wind to Aurora, CO. The difference of temperature between Aurora,

1 Mobile, Alabama Climate & Temperature [Internet]. [cited 2014 Oct 15]. Available from: http://www.mobile.climatemps.com2 Why Do Toothed Leaves Correlate With Cold Climates? Gas Exchange At Leaf Margins Provides New Insights Into A Classic Paleotemperature Proxy

AAT = (63.49)(0.3006) + 1.141

OF = (1.8 x 20.23)68.4 OF = (1.8 x 20.23)

Table 1. Leaf Margin Analysis: data from living plants of Mobile, AL; the known value for Mobile’s current AAT is included for comparison.

3 TEMPERATURE AND LEAF ANALYSIS FORMULA

CO and other areas would be about 5-10OF short of Aurora’s.Literature Cited

Royer, D. and Wilf, P. (2006). Why do toothed leaves correlate with cold climates? Gas exchange at leaf margins provides new insights into a classic paleotemperature proxy. International Journal of Plant Science, 167(1): 11–18. http://droyer.web.wesleyan.edu/leaf_teeth(IJPS).pdf

Seyfullah, Layla J. 2012. Fossil Focus: Using plant fossils to understand past climates and environments. Palaeontology Online, Volume 2, Article 7, 1-8.

3 Aurora, CO Weather [Internet]. [cited 2014 Oct 17]. Available from: http://www.usa.com/aurora-co-weather.htm/.