User:Megan Piccirillo/Notebook/Biology 210 at AU

Lab 2: Identifying Algae and Protists
Objective: To examine algae and protists from our transect, to understand the characteristics of algae and protists and to practice using a dichatomous key to identify species. (Bentley, 2015)
Introduction: This week we examined unicellular eukarya from samples taken from our Hay Infusion, which was prepared the week prior. The goal of the lab was to identify at least three organisms from the "top" of our Hay Infusion and three organisms from the "bottom" of our Hay Infusion, to ensure that we captured organisms that grow and live in different niches. I hypothesized that the organisms found at the "top" of our Hay Infusion would be different from the organisms that were found at the "bottom."

Hay Infusion culture jar: Sample taken from the "top," or the surface and from the bottom of the jar.

Bentley, M., Walters-Conte, K., and Nancy K. Zeller. 2015. A Laboratory Manual to Accompany: General Biology II. Department of Biology, American University: Washington D.C.. 22-23.

Lab 1:
Objective: To make careful observations about the characteristics of different species (Bentley, 2015).

Introduction: In order to achieve the above objective, I have observed a 20x20 ecological niche. My niche is located in the back of campus behind the “North side” residence halls. It is a relatively low traffic part of campus, as people do not regularly travel through the area to get to work, class, or their homes. The transect is part of a community garden on American University’s campus in Washington, DC. Within the transect, there are 4 wooden planters, each containing a different species of vegetation. I hypothesis that the soil/ground sample collected from the community garden will contain many species because of the varied factors within this niche.
Materials and Methods: To complete these observations, my group members and I walked to the transect and took notes using a pencil, paper, and a Smartphone’s camera (pictures below). We spent about 15 minutes collecting visual observations and also collected a soil/ground specimen using a 50mL conical tube. The specimen collected from within the 20x20 transect was used to conduct a Hay Infusion. Completing the Hay Infusion involved combining 500mL of water with 10-12g of the soil/vegetation/fecal specimen in a jar. 0.1g of dried milk was added to the mixture and mixed gently for 10 seconds. The jar was left unopened for a week to allow Protista to grow (Bentley, 2015).
Observations and Data:
The abiotic factors include:
• Direct sunlight, as there is no vegetation or constructed object to provide shade
• Frozen soil, due to recent temperatures
• Frost and ice on the plants, due to recent weather and temperatures
• 4 constructed 3x6 rectangular vegetation planters
• Fence: the area is fenced in, which provides protect from larger animals that may eat the growing vegetation

The biotic factors include:
• Woodchips surrounding the vegetation boxes
• Dried out grass and weeds surrounding the vegetation boxes
• Animal feces
• Decomposing plant matter in and around the vegetation boxes
• Vegetation variation of the planters (kale, cucumber, lettuce, and Brussels sprouts)

Conclusion: Based on our observations, there are many biotic and abiotic factors that influence this 20x20 niche. While I could visibly see multiple species of vegetation, I could not observe multiple species of bacteria or protista without a microscope. Next lab, we will use the Hay Infusion sample to look at organisms from out transect under the microscope. Perhaps, we will identify more species. MP
Sources:
Bentley, M., Walters-Conte, K., and Nancy K. Zeller. 2015. A Laboratory Manual to Accompany: General Biology II. Department of Biology, American University: Washington D.C.. 16-17.