Biosphere 2 is a world-renowned environmental and ecological research site operated by the University of Arizona, and located near Oracle, a small town approximately 15 miles North from the Oro Valley Hotel & Suites.
The name comes from Earth’s biosphere, Biosphere 1, Earth's life system and the only biosphere currently known.
Completed in 1991, it was designed so that scientists could study the complex interaction between natural life systems, including plant, animal and human, in a closed environment over an extended period of time.
Researchers also wanted to use Biosphere 2 as a place to conduct studies to evaluate the challenges and risks of closed systems in possible future space colonization efforts.
The interior portion of Biosphere 2 was opened to the public in the spring of 2002, and the University of Arizona offers guided tours of the facility.
The tour begins in the human habitat, where the original Biospherians lived, continues to the small farm where they grew crops, and then to the wilderness areas with desert, savanna, tropical rainforest and ocean environments.
Project:
Biosphere 2 is a new type of laboratory which combines state-of-the-art architecture and mechanical and computer monitoring systems with a wide range of living ecosystems. It is an experimental project where everything that happens - both expected and unexpected - provides valuable insights into our complex and evolving world.
While the biospherians further the research of more than 60 projects, 42 Ph. D.-level scientists are formally analyzing the information gathered inside Biosphere 2, as they study such topics as carbon dioxide and oxygen cycles, soil composition, coral reef health and vitality, agricultural pest management, waste and water recycling and more. Every two weeks, the biospherians send the samples they have collected through the airlock to scientific consultants and analytic laboratories for study.
Biospherians:
The four men and four women between the ages of 29 and 69 who live inside Biosphere 2 hail from the United States, England and Belgium. Their diverse backgrounds range from botany, agriculture and marine ecology to physiology, engineering and communications.
The crew is structured as an expedition, with co-captains serving as crew leader. Each biospherian is assigned specific responsibilities inside the biosphere, such as:
Managing and conducting research withing separte biomes.
Coordinating the biosphere's technical system.
Planting and harvesting crops.
Preparing daily meals.
Structure:
Covering 3.15 acres, Biosphere 2 is the largest closed ecological system in the world. Located near Oracle, Arizona, the glass and spaceframe structure measures seven million cubic feet in volume and stretches up to 85 feet at its highest point. Its steel struts are covered with a finish that insures against corrosion from inside or outside the biosphere. All air, water and nutrient cycles are completely closed and recycled within this system.
The monitoring of climate, air, soils and water within Biosphere 2 is unprecedented. Over 1,000 sensors distributed throughout the Biosphere send information to the sophisticated monitoring and control system located on-site at Mission Control. This elaborate computer network provides a continuous display of environmental variables and the status of engineering controls - while constantly
updating the permanent data base
Seven Ecological Zones or Biomes:
The ecological systems of Biosphere 2 include agriculture, a human habitat, an ocean, a tropical rainforest, a savannah, a marsh and a desert. Each different biome was built from scratch - with carefully selected soils, water and plant and animal life, collected from all offer the world. Biosphere 2 sustains high biodiversity with approximately 3,800 living species within its glass walls.
Points of Interest:
Biosphere 2 has successfully sustained eight humans and thousands of other life forms for 24 months.
The crew of Biosphere 2 has set a new world record for living in a closed system by surpassing the previous record held by Russian researchers in their experiment.
One of the most striking accomplishments for Biosphere 2 is its massive recycling systems. For the past 24 months, the Biospherians have used the same water and recycled all waste products in their environment. Each action made by a Biospherian has an immediate effect on this mini-world, which dramatically demonstrates the importance of individual accountability for the larger closed system, Earth, in which we live.
On just one-half acre of land, the eight Biospherians have grown, harvested and processed their food for 24 months - while keeping the soil highly fertile and using only non-polluting pest control methods. Application on Earth of similar systems show promise for reducing ground water pollution from agricultural chemicals, production of pesticide-free foods and more efficient food production.
Biosphere 2 is a uniquely designed structure where technology is used for the benefit of ecology. In their world, the biospherians manage and control every system from waves, tides, waterfalls and currents to rain, temperatures and humidity.
The biospherians are conducting research on how to restore natural endangered habitats, such as rainforests or coral reefs. While in this closed structure, the Biospherians are gaining knowledge about the forces that either degrade or enhance an ecological system and will be able to apply this information to areas that are actually threatened on our planet.
The exchange of Biosphere 2's air with the Earth's air, called a "leak rate" is under 10 percent a year - making Biosphere 2 the most airtight structure of its kind ever built. This extraordinarily low leak rate is far less than any other closed system experiment previously conducted.
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.
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