Under construction in the Santa Catalina mountains on the edge of the Sonora Desert here is a sprawling, 2.25-acre structure. In December, 1989, eight pioneers will step from the arid landscape into the greenhouse-like building and seal the door behind them--for two years.
The structure, called Biosphere II, will be a sealed-off, self-contained microcosm of the world. It is an unprecedented attempt by venture capitalists to test the creation of a closed environment capable of sustaining itself for a long period, such as during a manned trip to Mars, and its success is by no means assured, experts say.
When completed, Biosphere II is to contain seven different ecological zones, including a tropical forest, a 35-foot-deep "ocean," marshland, savanna, desert and a round, four-story adobe tower with offices and apartments for its human residents.
Before they enter, the "Biospherians" will have stocked the 5 million cubic feet--about half the volume of the Inglewood Forum--of Biosphere II with more than 4,000 species of plants, several hundred fish, a wide variety of insects, several pairs of birds, a flock of chickens for eggs and meat, and a few goats for milk.
Cut Off From World
But once the door is closed, the Biospherians will receive only sunlight and electronic communications from outside. They will be able to exit only in the event of a medical emergency.
Inside, nothing will go to waste. Carbon dioxide exhaled by the eight people will be used by the plants, which will in turn produce oxygen for the humans. Air will be purified by forcing it through packed soil in a new process developed specifically for the project.
Human wastes will be used to nourish the agricultural crops as well as algae, bacteria and water plants that will be fed to the fish and farm animals.
Such a self-supporting system will be necessary for extended space trips, experts say, because it is too impractical to take along enough food, water, and air for such a mission. "We want to blaze the trail for outer space," said Margaret Augustine, project director.
The only other completely closed ecologies that scientists have developed are sealed glass globes containing a small species of shrimp, some algae and various microorganisms. The microorganisms live on waste from the shrimp, the algae eat the microorganisms, and the shrimp eat the algae.
The globes, which fit in the palm of one hand, were developed by microbiologist Claire Folsome of the University of Hawaii to show that it is possible. The first globes he constructed 17 years ago are still thriving in his lab, he said. These "Ecospheres" later were sold--for $250 each--by mail order by Engineering Research Associates of Tucson.
It is a great leap from these simple globes to the intricate complexity of Biosphere II, however. Tens of thousands of individual decisions must be made about what plants will be grown, what insects will be tolerated or encouraged, what animals will be allowed--and mistakes could have disastrous effects on the system.
If the insect population grows too large, for example, pests could decimate the crops. If some insects were to die off, some crops might not get pollinated.
Some scientists think that Biosphere II is too big a leap to make in one step. "I think they are trying to fly before they walk," said ecologist Basset Maguire of the University of Texas.
But others argue that only by studying such complex interactions can scientists test hypotheses about the delicate balance of nature.
"I see the big payoff of Biosphere II as learning how to do a better job of stewardship of Biosphere I (the Earth)," said Carl N. Hodges, director of the prestigious Environmental Research Laboratory at the University of Arizona, which is the primary scientific contractor for the project.
After the two-year experiment, Augustine speculated, Biosphere might serve as a safe site for experimenting with genetically engineered microorganisms, for nurturing endangered species, or simply as a showcase to alert the public to the dangers of pollution.
Workers broke ground for Biosphere II at the end of January, but Space Biospheres Ventures Inc., the project's corporate parent, already has an impressive array of facilities here at Sunspace Ranch, a 2,500-acre conference center about 30 miles north of Tucson.
The site bustles with activity. In a modern laboratory, one of the Biospherian candidates is raising plants from individual cells, mass producing the types of plants that will be grown in Biosphere II. The 17,000 square feet of greenhouses are filled with plants being tested in a variety of soils and in tanks containing only liquid nutrients. Several varieties of fish are being grown in large tanks, their growth carefully monitored to see which plants provide them the most nutrition.
And even as one group of workers is preparing the foundation for Biosphere II, others are constructing additional greenhouses and other facilities where new plants and animals will be quarantined and stored until Biosphere II is ready to receive them.
Biosphere II is no shoestring project. It is financed with $30 million supplied primarily by a somewhat eccentric Texas multimillionaire, Edward P. Bass. He previously provided $15 million for a series of ecologically oriented projects conceived by John Allen and Mark Nelson, principals of the London-based Institute of Ecotechnics, which conceived and manages Space Biospheres Ventures.
Hotel in Katmandu
One such project is Hotel Vajra in Katmandu, Nepal, which caters to adventurous travelers, scholars and students of Asian cultures and religions. The hotel has a library of Eastern and Western works where, Bass spokeswoman Terrell Lamb said, "one might find a Western scholar studying ancient Asian religious texts and a Tibetan lama studying Western management techniques."
The institute also operates the R/V Heraclitus, an 82-foot, concrete-reinforced replica of a 15th-Century Chinese junk that sails the world studying undersea life, Lamb said.
Despite its unusual nature, the Biosphere II project has been able to attract a stellar array of scientists.
Botanist Ghillean Prance of the New York Botanical Garden, for example, is designing the tropical rain forest section of Biosphere II. Marine biologist Walter Adey of the Smithsonian Institution is developing the ocean and marsh regions.
Entomologist Scott Miller of the Bishop Museum in Hawaii will be selecting insects for the project. And Peter Warshall of the office of arid land systems at the University of Arizona is designing the savanna area and selecting vertebrates for Biosphere II.
Melding the work of these and other scientists will be the job of Hodges and the Environmental Research Laboratory, which also designed the EPCOT Center's Land Pavilion at Walt Disney World in Florida. That 6.5-acre exhibit routes visitors through displays representing agricultural regions around the world. The lab also has extensive experience in developing aquaculture and agricultural projects in arid regions of the United States, Mexico and the Middle East.
The Biospherians' quarters will include individual apartments, laboratories, a library and computer, communications and office facilities. It will also contain a small amphitheater for meetings and recreational activities.
The Biospherians will have telephones, radios, televisions and computers. And they will be able to electronically receive newspapers and mail. Television programs and the latest movies will be piped in.
Hodges estimated that each Biospherian will spend about four hours per day on maintenance, with perhaps half that occupied in the agriculture section. The rest of the workday is to be devoted to various scientific experiments. Each person is to be able to work on a wide variety of projects and be ready to cope with potential problems.
"The challenge," Hodges said, "is to design it so that we don't work everybody to death."
Both the National Aeronautic and Space Administration and the Soviet Union are attempting to design closed environments for space flight, but their projects are much more limited in scope.
The Soviets have not released much information about their Bios project, which is conducted at a research institute in Krasnoyarsk, Siberia. But, according to astronomer Carl Sagan of Cornell University, who has consulted with Soviet scientists on the topic, it is smaller and less ambitious than Biosphere II.
NASA's Closed Ecological Life Support Systems project is still less advanced, according to project director James H. Bredt. Because of limitations of space and weight in a prolonged manned mission, he said, NASA is trying to develop mechanical systems for purifying air and water, rather than the biological methods employed by Biosphere II.
For the same reasons, he added, food for each astronaut would have to be grown in an area of about 45 square feet. Thus, each astronaut would have only two or three plants to supply virtually all of his food--"typically a carbohydrate producer like potatoes and an oil producer like soybeans."
More Diverse Diet
The Biospherians, in contrast, would have a much more diverse diet, Hodges said. They will raise fish, chicken and goats--and also grow as many as 139 different types of agricultural plants, he said.
A typical diet for a Biospherian would include eight ounces each of chicken and fish per week, two eggs and four cups of goat's milk per day, 361 grams of cereals and legumes (beans and peas) per day, and assorted vegetables and fruits. Their diets are to total 2,364 calories per day.
They will also have 10 coffee trees, enough for about one to two pounds of coffee per year, and a small vineyard that should be capable of producing enough wine "for ceremonial occasions," according to horticulturist Merle Jensen of the Environmental Research Laboratory.
"There are very few things they won't have," Jensen said. "They just won't have as much of each thing as they might like." One notable exception will be dairy products--because enough food cannot be grown to support cows.
Selecting the 137 different food crops will be a massive job that will require screening between 3,000 and 4,000 different crops, Hodges said. "Each must be grown under the precise conditions of light, day length, and temperature it will encounter in Biosphere," he said.
Already there have been some surprises. "Wheat grows better in the winter than we expected and not as well in the summer," he said, "so we will grow more of other crops like sorghum in the summer." Hodges expects to continue making such decisions right up to the time the building is finally closed off.
Pollination of the agricultural plants is a potential problem. Bees cannot be used, botanist Linda Leigh said, because they navigate using ultraviolet light, which is screened out by the glass windows.
Hummingbirds will probably be used for pollination, Warshall said, but determining that they can survive in Biosphere II required many calculations.
Initially, he did not think that hummingbirds could be used because two would require nectar from at least 3,200 flowers every day. "After some very careful calculations," Warshall said, "we found to our surprise that we could support a pair" because at least that many flowers will be blooming at any given time in the agricultural region.
But which pair? Some hummingbirds have very curved beaks that cannot get into many flowers, some have very short beaks that cannot get nectar from large flowers. Some have complicated mating rituals that require more airspace than is available in Biosphere II.
Eventually, Warshall decided on hummingbirds with a fairly straight beak of medium length, he said. "And then we have to say to the botanists: 'Don't put in flowers they can't use.' " So far, he has narrowed the number of candidate hummingbird species from 314 down to five. "No one has ever performed detailed studies like this before," he said.
Similar studies of food supply, habitat and potential predators will be necessary for virtually every organism that is placed in Biosphere II, he said. He is now determining whether the project can support bats, turtles, snakes and even a small monkey.
Some potential problems are less obvious. One has led to what is now being called the "great termite taste test."
Grasses in savannas tend to grow in spurts, Warshall said, after which the grass must be broken down again for recycling. In the wild, this might be accomplished by antelopes eating the grass or by brush fires. But there will be no antelopes or other large animals in Biosphere II, and no fires.
Termites can break the grasses down, Warshall said, "but they also have a tendency to eat other things," such as the sealants used to hold glass panes in the structure. Warshall and the others are thus now testing several different strains of termites to see which of the potential sealants they will or will not eat.
All of the different regions within Biosphere II share the same air, although the human habitat and the intensive agriculture area can be separated from the rest of the building and operated independently for experimental purposes or in case of a malfunction.
Biosphere is built on the side of a hill so that differences in altitude and temperature will create convection currents to circulate the air. Even so, it may be necessary to supplement natural flow with fans. Solar-powered cooling coils over the tropical forest region will be used to condense water vapor, thus providing "natural" rainfall. Other areas will be irrigated.
NASA's Bredt also thinks that Biosphere II is unnecessarily complex. But he noted that "they are doing a very interesting experiment, and certainly some of the technology that they will be developing should be of use in the space program. We've been keeping in active touch with them and discussing the development of some joint projects."
But Bredt cautioned that it will be a long time before anything like Biosphere II can be built anywhere but on Earth. "I don't think it would be conceivable to ship the components to the moon or to Mars. You would have to wait for a local industrial base to develop so you could build it from indigenous materials."
"In my view, there will never be something like this that is put together on the ground and launched bodily into space, said former astronaut Russell L. (Rusty) Schweickart, who is now an independent aerospace consultant in Washington. "What will go into space is the knowledge and experience gained in a self-contained biosphere like this. . . . What they learn will be extremely important.