OVERVIEW:

Biosphere 2 has met the challenge of developing a sustainable agriculture system. The eight crew members managed to operate the system producing food for themselves and their domestic animals without the use of toxic chemical pesticides or artificial fertilizers on approximately one-half acre, recycling water and nutrients within the system. This was an encouraging beginning for the first two years of what the creators of Biosphere 2 hope will be a one hundred year experiment during which the agriculture systems will be further developed.

PRODUCTIVITY:

Despite unprecedented low light levels for both years of the experiment, the Biosphere 2 crew produced about 80 percent of their food. (The final figure will be available in October, 1993). The other 20 percent was drawn from a three-month food supply that was grown inside the Biosphere before the experiment began and from seed reserve stored inside the Biosphere before closure.

In the first year the agriculture system produced more than 7 tons of foodstuffs for humans and 15 tons of fodder for the domestic animals.

The Biospherians grew 86 different crop species. The crop varieties were selected to provide nutritional balance and a varied diet.

Cultivation was carried out entirely by the eight crew members who devoted about one third of their workday to agriculture.

The agriculture system combines both ancient and modern techniques. For example, the rice/fish/azolla system used goes back to ancient China, whereas the humidity and temperature control and monitoring is achieved with advanced equipment.

SOIL CHEMISTRY:

The agricultural system was designed to be soil-based. This meant that nutrients could be returned to the soil using composting techniques.
Initial tests on the soil condition made 18 months into the experiment showed nutrient levels to be adequate.
The continuous monitoring and management of the agricultural soils will be one of the main focuses of agricultural research in Biosphere 2 as the experiment continues.

PEST CONTROL:

One year prior to closure and during the first two-year mission, the Biosphere 2 term practiced integrated pest management - an approach that uses various non-toxic methods of pest control that include the introduction of beneficial insects (those that feed on pests) and crop rotation. This approach has recently been endorsed by the Clinton Administration, and is being encouraged by the Environmental Protection Agency, the Food and Drug Administration, and the Department of Agriculture.

No toxic chemical pesticides have been used in Biosphere 2.

During the transition phase there will be a thorough survey of the insects in the agriculture system to determine the next steps in this biological pest-control program.

"For the first two years of this one hundred year experiment the agriculture system has been a great success and shows that we are definitely developing a sustainable system. We have faced some big challenges including unusually low light levels for Arizona, but in spite of this we managed to produce approximately 80% of our food. The diet has been varied and interesting and all of us have enjoyed honing our cooking skills."

"The development of our soil management and pest control techniques over time will, I think, be significant not only for the design of future Biospheric systems, but also for the development of farming techniques in Biosphere 1 - planet Earth. "

Sally Silverstone
Biosphere 2 Co-Captain
& Director of Agricultural and Food Systems