Final Observation (Friday, Nov 12)

Changes:

My microaquarium looked very cluttered this week. I observed an increase in euplotes, cyanobacteria, and paramecium. The middle of the tank was characterized by a great amount of debris, diatoms, bacteria, and various motile organisms. In some places, the cyanobacteria grew in clumps so thick that rotifers had trouble swimming through it. In the soil layer, organisms were living underneath the soil at the very bottom of the tank. These organisms included annelids, large rotifers, and nematodes. Near the top of the tank, my plants continued to decay.


Organisms:

Annelids: I found this annelid (Egmond W V, 1995) burying large tunnels in the soil layer. It was so long that I could not view it all at once. It moved in fast, jerky motions, constantly burying deeper into the soil.

Unidentifiable amoebic organisms: These organisms, which I previously thought were difflugia, changed shape since last week. They proved impossible to identify. Last week they were circular, clear and smooth. This week they had increased by at least double or triple and had developed scales. They also were enclosed in a clear, gelatinous matrix that held them together.

Rotifers: I did not observe an increase or decrease in my rotifers, however, many changed in size and color. In this picture, I caught one feeding near the discarded molted shell of an ostracod.

Flatworms: This is the same flatworm (Egmond W V, 1995) that I have been observing for the past 4 weeks. I found it near the soil layer, where it usually is.

Green algae: This is coleochaete (Tiffany LH, Britton ME, 1952). I only found one cluster of them, at the bottom of the tank.


















Bibliography:

Tiffany LH, Britton ME. 1952. The Algae of Illinois. Chicago, Illinois: The University of Chicago Press. 39 p. Figure 76.


Egmond W V. 1995 [cited 2010 Nov 14].Worms. [Internet]. United Kingdom: Microscopy-UK. Available from: http://www.microscopy-uk.org.uk/mag/indexmag.html?http://www.microscopy-uk.org.uk/mag/wimsmall/smal1.html.


Egmond W V. 1995 [cited 2010 Nov 14].Rotifers. [Internet]. United Kingdom: Microscopy-UK. Available from: http://www.microscopy-uk.org.uk/index.html?http://www.microscopy-uk.org.uk/pond/index.html.

Week Three Observations (Thursday, Nov 4)

Changes: There was not a dramatic change in my microaquarium compared to last week. Just like every week, water had evaporated. I observed a slight increase in the number of organisms in addition to an increase of dead matter. Most of the dead debris was on the bottom of the tank, but there were also parts of my water moss and bladderwort that were decaying (near the surface of the tank).

Organisms: The most obvious change concerning life in my tank was an increase in nematodes, seed shrimp, and centropyxis.

Nematodes: I found this one on the bottom of the tank. It was very busy digesting whatever it could vacuum into its mouth (Patterson, 1996). I found several more nematodes squiggling around in my water moss, bladderwort, and soil.

Paramecium: This is a Paramecium Bursaria (Egmond W V, 1998). I found it near the surface of the tank. I spotted at least three more around the plant matter and near the soil. It swam rather fast, while it swam the Zoochlorella algae inside circulated rapidly (Egmond W V,1998). The paramecium has a symbiotic relationship with the algae.

Centropyxis: These organisms appeared in huge clumps all around the water moss and in the soil. They are unicellular and stationary (Patterson, 1996). Centropyxis is an amoeba that usually has spines on the outside. These are young and therefore have not developed their spines yet.

Ostracods: Last week I only found one seed shrimp. This week, however, I saw two or three on the bottom.

Cyanobacteria: The number of cyanobacteria remained unchanged from last week. Once again, I found them everywhere.

Plants: Both my plants showed signs of decay. The water moss had chunks worn away from their previously pointed leaves and the coloration was turning from bright green to brown on the tips.


Diatoms: I observed a slight decline in the number of diatoms. A few on the bottom could have been dead, but it was hard to tell since my diatoms are normally stationary.


Rotifers: These guys were all over everything. I spotted at least nine, all of whom were feeding on either bacteria, plant material, or on material on the soil layer.


Flatworms: I found one huge flatworm on the bottom of my tank. It was obviously the same one from last week.




Citations:

Patterson D. 1996. Free Living Freshwater Protozoa. A Colour Guide. Drawings by Stuart Hedley. 73 Corringham Rd, London NW11 7DL: Manson Publishing. 28 p. Figure 18.

Patterson D. 1996. Free Living Freshwater Protozoa. A Colour Guide. Drawings by Stuart Hedley. 73 Corringham Rd, London NW11 7DL: Manson Publishing. 95 p. Figure 184.

Egmond W V. 1998 [cited 2010 Nov 7].Green Algae. [Internet]. Microscopy-UK. Available from:http://www.microscopy-uk.org.uk/mag/indexmag.html?http://www.microscopy-uk.org.uk/mag/wimsmall/smal1.html