Final Ecosphere Post by Group [4.0 A]

Ecosphere Blog Post by John, Tony, Kyle, and Ali

Results:

In order to study biological science, we set up a controlled ecosphere experiment over a month ago. It thrived and lived for most of the part. The results were very interesting as they were both expected and unexpected. The observation of ecosphere every week allowed us to notice different results; thus, forcing us to hypothesize accordingly. Following are some of the findings that were observed:

• The growth of plant Bacopa thrived for the most part as expected. 
• Shrimp lived through the whole experiment. Although the initial hypothesis was that it will grow in size, but the growth was observed to be normal. 
• Green algae flourished prolifically which was a surprised result that was observed.
• Finally, the 20 count Daphnia that were included in the ecosphere on Day 1 did not survive through the experiment. Our initial hypothesis was that the Daphnia will grow in size but the actual results were very unexpected.

Observations from May 11:

Figure 1: Green algae can be observed in large quantities. 

Figure 2: Close up picture of green algae growth and two snails. Although the snails were not added to the ecosphere, but they were observed in the ecosphere. It was hypothesized that they were probably attached to the plant while setting up the experiment on Day 1.

Observations from May 13:

Figure 3: Compared to May 11 observations, this time the growth of green algae is relatively less. The reason is that the ecosphere was moved from the corner, where sunlight was not as abundant, to the middle of the row where there was a bit more sunlight. 

Observations from May 18:

Figure 4: Gametophytes of plant Bacopa.

Discussion:

We had initially added bacterium Anabaena to provide nitrogen fixation and inorganic nutrients for the plants. The fact that Bacopa plant shed their gametophytes is an indication that plants had good growth in the ecosphere. Nonetheless, the Bacopa plant that was sticking above the water portion had healthy internodes and leaves; whereas, the portion of the Bacopa plant below the water had somehow unhealthy look to it. It was hypothesized that green algae was competing with plant for oxygen and nutrients. In addition, Bacopa and green algae were hypothesized to be the food source for Shirmp and Daphnia. Although shrimp lived through  the experiment, Daphnias were dead in the second week. We hypothesized two things: First was that maybe Daphnia couldn't utilize the green algae very effectively as food source; thus, that is why they died. Secondly, we stated that maybe Daphnia were eaten up by shrimp because we couldn't see any trace of Daphnia, dead or alive, in the ecosphere. 

Our experiment set up was very similar with the group that included Taylor, Amy, Lisa, and Shawna. Although very similar set up, there are interesting differences between the two ecospheres. First of all, they don't have overly active green algae growth. Secondly, their Daphnia have survived through the experiment. One thing to be noticed though is that the shrimp in their experiment was dead in the initial stages. Therefore, maybe the reason their green algae didn't have the active growth was that because the Daphnia was there that utilized it as their food source.

References:

http://biol213-plants2.blogspot.com/2016/05/ecosphere-blog-post-bytaylor-jones-amy.html