Ecological Succession in Two Regions within
Kennesaw State’s Forest
Abstract
This study was conducted to determine the impact of ecological succession, specifically
secondary succession, in Cobb County by sampling Kennesaw State University’s
Arboretum and defining its effects on the surrounding communities. The Arboretum is
the forest behind the Science building where all pines and hardwoods were sampled by
their circumference to decide the “relative time since a major disturbance”, which is
outlined in the KSU Biology Department protocol for this ecology lab. Both a T-test and
a Fisher’s Exact Test were performed to calculate the difference in circumference
between tree species and the proportion of each in two separate regions. We
hypothesized that Region 2 is older than Region 1 because the trees in Region 2 are
generally larger, meaning there has been more time since the last disturbance that
affected tree growth in that area compared to Region 1. This is reflected in our results
shown in Figure 1 depicting the “Top 10 Largest Trees”, but Region 2 held the largest
from both regions. Tables 1 and 2 show the T-test and Fischer's tests performed, both
indicating that there was no statistical significance in the differences between the
distributions or proportions of the two regions. The lab identifies the differences between
the two regions based on tree size and specifies the significance, in this case, the
insignificance between two different forest regions.
Introduction
The main premise of this lab is ecological succession, which can be defined as the
predictable and progressive changes in the environment and species composition due
to a disturbance. The lab protocol explained that the tree makeup of Cobb County,
which includes Kennesaw, is an example of the previously defined succession due to
the contrast between pines and hardwood trees in the surrounding areas (KSU Biology.
2021). Succession can be categorized into primary and secondary; this is determined
, by the type of disturbance that has occurred. In the context of Kennesaw’s Arboretum,
we will focus on secondary succession because we surveyed an area that was
previously occupied and re-colonized following a disturbance within the ecosystem. In
the Arboretum, behind Kennesaw’s Science Building, you can find a variety of tree
species, and in this lab, we focused on deciduous species of Hardwoods and Pines.
Since hardwoods are known for their thick, strong features and pines are known for their
tall, skinny features, hardwoods will generally have a larger circumference compared to
pine trees. In addition, both hardwoods and pines are native tree species to Georgia, so
for the most part, there should be an equal proportion between the two deciduous tree
species within both regions. Successional stages are determined best according to the
amount of data that is provided; therefore, all deciduous trees of a certain quadrant
were accounted for.
Using the following information, we can pose the question of whether there is or is not a
difference between the separate regions based on tree size. Thus, we hypothesized
that between the two areas sampled, Region 2 is older than Region 1. The lower
elevation of Region 2 provides more favorable conditions for tree growth, in that the
trees are sort of hidden behind and protected from the uphill area of Region 1. This led
us to predict that the trees in Region 2 will be larger, since more time has elapsed since
the last disturbance, in comparison to Region 1. Our hypothesis is tested by measuring
and analyzing the circumferences from all hardwoods and pines within the two regions.
Materials & Methods
To accurately measure the secondary succession of the two tree species, we carefully
followed the ecology lab protocol which told us to divide the class into groups to
efficiently measure all the trees in Kennesaw’s Arboretum. The groups were first divided
up by sampling Region 1 and 2, where Region 1 was the uphill area and Region 2 was
the downhill area (KSU Biology. 2021). The next step was for each group to sample all
the adult trees within separate 100m^2 quadrants, 10-meter by 10-meter boxes outlined
with ropes prior, in their assigned regions. To record the circumference of the trees, we
first had to categorize them as Pine or Hardwood. Then, the tree had to be an adult
Kennesaw State’s Forest
Abstract
This study was conducted to determine the impact of ecological succession, specifically
secondary succession, in Cobb County by sampling Kennesaw State University’s
Arboretum and defining its effects on the surrounding communities. The Arboretum is
the forest behind the Science building where all pines and hardwoods were sampled by
their circumference to decide the “relative time since a major disturbance”, which is
outlined in the KSU Biology Department protocol for this ecology lab. Both a T-test and
a Fisher’s Exact Test were performed to calculate the difference in circumference
between tree species and the proportion of each in two separate regions. We
hypothesized that Region 2 is older than Region 1 because the trees in Region 2 are
generally larger, meaning there has been more time since the last disturbance that
affected tree growth in that area compared to Region 1. This is reflected in our results
shown in Figure 1 depicting the “Top 10 Largest Trees”, but Region 2 held the largest
from both regions. Tables 1 and 2 show the T-test and Fischer's tests performed, both
indicating that there was no statistical significance in the differences between the
distributions or proportions of the two regions. The lab identifies the differences between
the two regions based on tree size and specifies the significance, in this case, the
insignificance between two different forest regions.
Introduction
The main premise of this lab is ecological succession, which can be defined as the
predictable and progressive changes in the environment and species composition due
to a disturbance. The lab protocol explained that the tree makeup of Cobb County,
which includes Kennesaw, is an example of the previously defined succession due to
the contrast between pines and hardwood trees in the surrounding areas (KSU Biology.
2021). Succession can be categorized into primary and secondary; this is determined
, by the type of disturbance that has occurred. In the context of Kennesaw’s Arboretum,
we will focus on secondary succession because we surveyed an area that was
previously occupied and re-colonized following a disturbance within the ecosystem. In
the Arboretum, behind Kennesaw’s Science Building, you can find a variety of tree
species, and in this lab, we focused on deciduous species of Hardwoods and Pines.
Since hardwoods are known for their thick, strong features and pines are known for their
tall, skinny features, hardwoods will generally have a larger circumference compared to
pine trees. In addition, both hardwoods and pines are native tree species to Georgia, so
for the most part, there should be an equal proportion between the two deciduous tree
species within both regions. Successional stages are determined best according to the
amount of data that is provided; therefore, all deciduous trees of a certain quadrant
were accounted for.
Using the following information, we can pose the question of whether there is or is not a
difference between the separate regions based on tree size. Thus, we hypothesized
that between the two areas sampled, Region 2 is older than Region 1. The lower
elevation of Region 2 provides more favorable conditions for tree growth, in that the
trees are sort of hidden behind and protected from the uphill area of Region 1. This led
us to predict that the trees in Region 2 will be larger, since more time has elapsed since
the last disturbance, in comparison to Region 1. Our hypothesis is tested by measuring
and analyzing the circumferences from all hardwoods and pines within the two regions.
Materials & Methods
To accurately measure the secondary succession of the two tree species, we carefully
followed the ecology lab protocol which told us to divide the class into groups to
efficiently measure all the trees in Kennesaw’s Arboretum. The groups were first divided
up by sampling Region 1 and 2, where Region 1 was the uphill area and Region 2 was
the downhill area (KSU Biology. 2021). The next step was for each group to sample all
the adult trees within separate 100m^2 quadrants, 10-meter by 10-meter boxes outlined
with ropes prior, in their assigned regions. To record the circumference of the trees, we
first had to categorize them as Pine or Hardwood. Then, the tree had to be an adult
