25 November, 1999
Thursday November 25, 1999
Happy Thanksgiving. I woke up about 0630 hours. Normally by this time my potatoes and squash would all be peeled and cut, the stuffing made and put in the bird and Thomas would be happily roasting away in the oven. It really doesn't seem like Thanksgiving Day. Hopefully Saturday, when we celebrate the holiday, that feeling will come upon me.
Went to the lab and worked on journals. Barb stopped by to tell me she had found tartagrades, rotifers and nematodes in her mat sample from Lake Hoare and wanted to know if I'd like to see them. Does a duck like water? I finished what I was working on and went to the lab, sure enough living in the mat material she had collected were these three critters and probably a lot more, since her stereoscope had a maximum magnification of 5X.
Barb and I talked a while and both agreed that the stress was getting to both of us. I decided go sleep it off and Barb opted to work on her critters.
I returned at 1800 hours and met with Barb we cleared the air and then held our session. Tonight's speaker was Dr. mark Wells from University of Maine in Orno. He talked about the project that he was co-PI with the main PI Dr. Bess Ward of Princeton University. The topic of study was denitrifying bacteria. These are critters that can take NO3* No2 * N2. The focus of study is one of the dry valley lakes, Lake Bonney. Lake Bonney is permanently ice-covered, it has two different lobe separated by a small mound of earth between them and lends itself perfectly to an investigation looking at the role of bioactive metals. Because denitrification is the primary means by which fixed nitrogen is lost from an ecosystem, its rate and regulation may directly affect primary production and the cycling of carbon over short- and long-time scales.
The distribution of chemicals in the two lobes of the lake implies that denitrification occurs only in one lobe, but not the other. Earlier work has ruled out most obvious biological and chemical variables such as organic matter and pH or temperature differences. The presence of denitrifying bacteria in both lobes has been documented and samples from each lobe have been subjected to temperature and salinity testing and all respond to conditions consistent with those that are considered to be optimal. Because of this, the next most likely source of difference between the two lobes might lie in metal tolerances and requirements for growth and denitrification by denitrifying samples taken from each lobe.
Bottom line is that this project will examine the relationship between microbial activity and metal distribution in Lake Bonney this in turn has implications for elemental cycling in other aquatic systems. Do metals play a major role both, hypo-concentrations and/or hyper-concentrations, in the ocean's productivity? The accepted practice in looking at the paleobiology is to assume, as part of that model, that denitrifcation was the same in prior times than it is now. The happenings in the easetrn end of Lake Bonney, are beginning to shed doubt on that premise and may shake up this aspect of paleobiology. The other global piece to this puzzle hinges on the idea that certain areas of the ocean, including the entire Southern Ocean, exhibit HNLC (High Nutrients Low Chlorophyll). This situation is thought to be caused by the deficiency in this parcticular ocean of the element iron. Some people are proposing seeding the oceans with soluble iron, this in turn should cause algal blooms which in turn should reduce the amount of atmospheric CO2
After class I returned to my dorm to work on my journal.
Tomorrow is Thanksgiving at home. My you all find a way to reach out and touch your loved ones. It is hard being lonely in rather crowded quarters and while your real busy, but even those factors, can't ward off missing family and friends at times like these. Enjoy your family and friends.
Penguin Pete the Polar Man
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