Tucson Sights

Have had newly retired cousins visiting from Texas this past week.  They asked that I “order up all the javelinas and other wildlife that you write about to appear”.  So their first morning a family of javelina was munching seeds under the mesquite tree. 

A few days later a young bobcat had been resting in the shade in front of my house when we pulled in.   They also got to see lots of rabbits and birds up close and personal. 

(But they had missed the young coyote that had been in the yard on Monday.)  

Biosphere 2

Sent them off to the Biosphere 2 (now administered by the University of Arizona) on Tuesday as I had to have my radiation treatment, but was sorry that I hadn’t joined them.  It’s probably been 20 years since I’d been there and I hadn’t heard the latest on why they ran out of oxygen, and why the ocean died.  This from the internet:

What Went Wrong?

As an attempt to create a balanced and self-sustaining replica of Earth’s ecosystems, Biosphere II was a miserable (and expensive) failure.  Numerous problems plagued the crew almost from the very beginning.  Of these, a mysterious loss of oxygen and widespread extinction were the most notable.

Catching Their Breath

Starting when the crew members were first sealed in, Biosphere II experienced a constant and puzzling decline in the percentage of oxygen in the atmosphere. It was initially hoped that the system was merely stabilizing itself, but as time passed it became increasingly clear the something was amiss. Not quite 18 months into the experiment, when oxygen levels dropped to the point where the crew could barely function, the outside managers decided to pump oxygen into the system so they could complete the full two years as planned.

Obviously, Biosphere II was not self-sustaining if outside oxygen had to be added in order for the crew to survive. The reasons behind this flaw in the project were not fully understood until some time later. As it turned out, the problem had more to do with carbon dioxide than with oxygen. Biosphere II’s soil, especially in the rain forest and savanna areas, is unusually rich in organic material. Microbes were metabolizing this material at an abnormally high rate, in the process of which they used up a lot of oxygen and produced a lot of carbon dioxide. The plants in Biosphere II should have been able to use this excess carbon dioxide to replace the oxygen through photosynthesis, except that another chemical reaction was also taking place.

A vast majority of Biosphere II was built out of concrete, which contains calcium hydroxide. Instead of being consumed by the plants to produce more oxygen, the excess carbon dioxide was reacting with calcium hydroxide in the concrete walls to form calcium carbonate and water.

Ca(OH)2 + CO2 –> CaCO3 + H2O

This hypothesis was confirmed when scientists tested the walls and found that they contained about ten times the amount of calcium carbonate on the inner surfaces as they did on the outer surfaces. All of the walls in Biosphere II are now coated with a protective layer, but oxygen levels continue to be somewhat problematic.

Walking a Tightrope

The designers of Biosphere II included a carefully chosen variety of plant, animal, and insect species. They anticipated that some species would not survive, but the eventual extinction rate was much higher than expected. Of the 25 small vertebrates with which the project began, only 6 did not die out by the mission’s end. Almost all of the insect species went extinct, including those which had been included for the purpose of pollinating plants. This caused its own problems, since the plants could no longer propagate themselves.

At the same time, some species absolutely thrived in this man-made environment. Crazy ants, cockroaches, and katydids ran rampant, while certain vines (like morning glories) threatened to choke out every other kind of plant. The crew members were forced to put vast amounts of energy into simply maintaining their food crops. Biosphere II could not sustain a balanced ecosystem, and therefore failed to fulfill its goals.

Other Problems

Biosphere II’s water systems became polluted with too many nutrients. The crew had to clean their water by running it over mats of algae, which they later dried and stored.  Also, as a symptom of further atmospheric imbalances, the level of dinitrogen oxide became dangerously high. At these levels, there was a risk of brain damage due to a reduction in the synthesis of vitamin B12.  And of course, there were inevitable disputes among the crew, as well as among those running the project from the outside.

Desert Museum

The next day I changed my appointment to late afternoon and went to the Desert Museum with them.  Was disappointed to learn that the Ironwood Terrace Restaurant was closed for the summer and the raptor flights (see
https://notesfromthewest.wordpress.com/2011/02/15/visitors/) don’t start until October.  Of course, tourism is cut back during our five months of summer.  (Actually, the Desert Museum noted that we have five seasons,  including two summers: spring, dry summer, monsoon summer, fall, winter.)  My best photo was this butterfly in the butterfly garden.

Titan II Missile Museum & Asarco Copper Museum Open Pit and Mill tours

Then, as my radiation treatments are in Green Valley, on Friday they took me and afterwards we did the sights there, the Titan II Missile Museum:

… the site of one of the Cold-War-Era Titan ballistic missiles that, for over twenty years, formed a ring around the Tucson basin. On your underground tour, you can see the immense 740-ton roll-back silo door, sit in a launch-control operator s seat at the control panel, and watch demonstrations of monitoring and countdown procedures. Outside, see the real rocket engines that powered these massive devices.

and Asarco Copper Museum Open Pit and Mill tour:

neither of which I had seen before, and both of which were way more interesting than I had anticipated.

Wrapped up their visit with dinner at Primo, an excellent Italian restaurant at the JW Marriott Starr Pass Tucson Resort & Spa which is walking distance from my house.  Primo!

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One Response to “Tucson Sights”

  1. Jim Says:

    Nice photos of beautiful beings. I would be inclined to give them names, much as Jane Goodall did with her chimp friends.
    When I was a biology student, I lived in the home of professor’s surviving wife, in exchange for cold cereal and hot coffee for breakfast and yardword Saturday morning. We got along superbly. She felt that she needed the gardening help and someone to watch her home when she traveled. She had been been looking for a student to help her with houseworking, but I explained that I only enjoyed gardening work. She was delighted with my gardening work, and happy to be helping a student get through college. I also had to promise not to bring girlfriends into my room.

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