User:Jamie Nunziata/Notebook/Biology 210 at AU

Observing a Niche at AU

01/26/2015 J.N.

Introduction:
This lab was performed to serve an introduction to ecology, the branch of biology that studies the different relationships between organisms, species, and the environment (Bentley et al., 2015). In this lab, a transect, or a small section of an ecosystem, was observed to identify any biotic and abiotic factors. Biotic factors are living things, such as moss, and abiotic factors are nonliving things, such as a stop sign. Samples of dirt the various transects were also taken to perform a Hay Infusion Culture that will be observed in the following lab. The purpose of this experiment was to gain a better understanding of the abiotic and biotic factors of different ecosystem by observing specific and unique transects across American University's campus.

Materials and Methods:
The class was first split into groups and assigned different 20 by 20 meter areas of campus to use as their transect. Once each group got their assignment, they went to their assigned area and received a tube from the instructor to take dirt samples from their transect to perform a Hay Infusion Culture in their next lab. The groups then comprised a list of abiotic and biotic factors in their transect along with recording the transect's overall location and topography. Each group member then, independently, sketched their transect to include an overall biological setup of biotic and abiotic factors, along with a having labelled north, south, east and west.

Data:
The transect that was used for this analysis was the Tall Bushes Transect and was located in the middle of an arboretum in between the amphitheater and bender arena. This transect included lamp posts, dirt, and sidewalk cement as its abiotic factors. As far as the biotic factors, this transect contained many different types of ground shrubs and bushes, some small trees, grass, small bugs and microorganisms in the dirt, and some fallen leaves. The overall topography of the transect was that it was flat and higher up in altitude than it's surroundings, and the transect was fairly dry when digging past the top layer of snow. A sketch of the transect can be seen below:

Conclusion:
This lab was aimed toward making observations about a specific ecosystem by analyzing a small sample, or transect, of that ecosystem. The results of this experiment were that most of the biotic factors in our transect were small trees and bushes on the ground, which is an outcome of the fact that our transect was in a dry and high up location. This location was also in an area where their is no immediate water source, also contributing to the observation that the only plants able to sustain life in our transect were ones which could survive in dry areas.

References:
Bentley, M., Laslo, M., Walters-Conte, K., & Zeller, N. (2015). Aerobic Respiration & Fermentation. In A Laboratory Manual to Accompany General Biology 2 (pp. 16-17). Department of Biology, American University.