Conduct background research on ecosystem interactions and community ecology to gain an understanding of pond ecology and nutrient cycling.

Ecoflask Assignments

The Ecoflask lab runs over two lab periods, and there are several assignments associated with this lab (see the lab

manual and syllabus). The Ecoflask journal is due the week before the practical (30 November 2015) and includes

the following assignments:

Observations: Conduct background research on ecosystem interactions and community ecology to gain an

understanding of pond ecology and nutrient cycling. Then, create a closed-system aquatic community (ecoflask) and

make observations of change over time. (See directions in Ecosystem Interactions lab handout)

Hypothesis: Write a complete scientific hypothesis, which includes a prediction statement, based on your

understanding of ecosystems and community ecology and the initial observations you made of the ecoflask. The

hypothesis should relate to the overarching theme of the lab: ecosystem interactions. Create a hypothesis that you

are interested in testing during this two-week lab activity.

Experiment: Choose an experimental treatment. Your treatment should allow you to test your hypothesis and draw

conclusions. The following are potential tests:  Nutrient limitation or supplementation

 Introduction of an aggressive predator

 Introduction of a non-native organism

 Increase or decrease of particular trophic resources Note: Control treatments can be provided by the instructor. Results: Observation table (all original data sheets) with a drawing and description, identification, count, location/niche, and

other relevant information of the organisms observed in your Ecoflask  Draw a picture and describe of each of the different organisms you encounter and try to identify them.

 Note the “niche” of the organism: the region of habitat it occupies (plant, water, dirt, etc)

 Note the approximate number of individuals of the organisms in the flask. Use a classification system that provides information within a range of abundance [e,g,. absent (0), rare (1-5), moderate (6-15), widespread

(more than 15) — you may design your own method of quantification based on what you observe].

 Use the provided datasheet or design your own observation sheets based on your experimental objective. Be sure that the above information is included and that the data display is clear to your instructor.

Figure 1 : Using data from the first week of observation of your Ecoflask, make a graph showing the species

composition of organisms in your Ecoflask (Hint: abundance on y-axis, series of “species” on x-axis).

Figure 2: Calculate species richness for each of your observation days. Species richness is number of different

species in your Ecoflask. Make a graph that shows the change of species richness over time (week 1 to week 2).

Figure 3: Create a graph that shows change over time of your experimentally manipulated variable.

All graphs must include figure captions; specific hypotheses are not necessary. Discussion: Journal questions: Write thoughtful and complete answers to the series of discussion questions on the ecoflask

journal handout. Remember to use good scientific writing, which includes active voice, full sentences, proper

punctuation, and appropriate scientific vocabulary. The journal questions also include an illustration of a nutrient

cycle that is operating within your ecoflask.