Observations November 13, 2009

Observations
The final week of observations for MicroAquariums has arrived and marked by noticeable differences in the MicroAquarium. With the naked eye it can be seen that the MicroAquarium has become greatly reduced in the amount of water it contains. Comparatively from the first week of observation to thelast week the amount of substrate has also become reduced. Plant B (the carnivorous plant) has also appeared to become susceptible to the effects of aging as that of Plant A (Amblystegium varium) has exhibited progressively more each week.

At the microscopic level the green algae (Coleochaete scutata) is still quite common throughout, and the many Rotifers of the phylum Rotifera appear to have gotten larger than in previous weeks, while the nematodes (related to the rotifers) are still quite common.


(Larger Rotifers)


(Coleochaete scutata)


More can be found out about rotifers and nematodes and how they interact with their environment by following this link: http://water.me.vccs.edu/courses/ENV108/lesson7b.htm


Discussion
The decline in water level of the MicroAquarium is expected to have an influence on available living space for the organisms to make use of and consequently make organisms compete for more resources, possibly accounting for the bigger rotifers that were observed. The most successful rotifers were the ones that lived and made the best use of their limited living space.

As the last week of observation it will be impossible to witness the continued interaction of the MicroAquarium inhabitants. It can be expected though that given the gradual shrinkage of available living space and continual lack of food source, that the MicroAquarium and its organisms inside would inevitably die.

MicroAquarium Observation November 6th Observation

The 4th week of observation is now under way and the most noticeable difference between week 3 and 4 appears to be life witin the MicroAquarium has plateaued to the same level as week three.

There appeared to be no noticeable creatures found this week as opposed to the previous week as various rotifers, diatoms, green algae, and nematoads were all observed easily at 10x magnification.

Other noticeable observations with the naked eye include reduced water level, which should expected in this junction of observation, the remanant food plot of the previous week was now gone, and plant B was now noticealby more resisant to the effects of aging than plant A.

What I feel is one of the most interesting creatures in my MicroAquarium is the Rotifer (as seen in the photo below). Rotifers are multicellular animals that are 200-500 micrometers long (www.ucmp.berkeley.edu/phyla/rotifera/rotifera.html) The name Rotifer coming from the latin word meaning "wheel-bearer"(internt.nhm.ac.uk/jobj/runjava.jobj?java=ctol.CTOLServer&method=printNamePage&accountref=987&NAMEID=13689.

Rotifer of the phylum Rotifera (ucmp.berkley.edu)

As the last week of observation approaches, it could be assumed that due to this weeks lack of new organisms that next would not be any different. I attribute the productivity of week 3's observations to the food pellet, without the food source the MicroAquarium is not as productive.

Botany 111 Observation October 30, 2009

October 30, 2009 the Botany 111 MicroAquarium was observed. Observations by hand were done first and showed had similar qualities to that of previous weeks observations. The substrate was still segmented into three distinct sections. Plants A and B were both wilting and gradually losing their green color. The food pellet that was placed in the aquarium from the previous week was still present and looked unaffected other than being wet from water submersion.

Immediately upon microscopic observation under 10x the obvious creatures seen were multiple rotifers, green algae, and nematodes. The abundance of life was much greater this week than the previous week.

Rotifers are metazoa and are in the same class as nematodes and flatworms (Patterson 1996).

Coleochaete irregularis a type of green algae, identification made easy by the non-tapered ends (Forest 1954).

An addition that was found within this weeks MicroAquarium was the addition of Vorticella. You can notice within the video posted below that these organisms are highly sensitive to any movement.

While these are the most prevalent organisms found within the MicroAquarium it can be assumed that based on this weeks large growth of orgainsms from the previous week that next week may still some growth in abundance, but not quite to that of this week as last week was when the MicroAquarium was given a food pellet.

Sources Cited

Forest, Herman Silva. 1954. Handbook of Algae. The University of Tennessee Press.

Patterson, D.J. 1996. Freeliving Freshwater Protozoa A Color Guide. Manson Publishing. London.