When the first phase of the Biosphere 2 experiment was completed on September 26, 1993, a transition period began. Teams of nationally prominent consultants, experts in their various fields, came to study Biosphere 2 before its next phase.

The transition was marked by three main areas of activity: research, technical upgrades, and biospherian training. The research tasks consisted of harvesting the vast amount of data on the behavior of biospheric systems generated by the two-year mission, and installing new data collection systems for projects during succeeding missions. Construction crews focused on upgrading technical systems to reflect knowledge and experience gained during the first two years. The new biospherian team spent five months in training, learning to manage the complex systems they will operate for the next ten and a half months.

Waste/water/air Recycling

Since September 26, 1991, Biosphere 2 has been maintained as a closed system. Researchers, technicians and operators entered and exited the facility through the airlock chamber during transition (September 26, 1993 -March 6, 1994) to complete research programs, make necessary technical systems changes, and to operate the Biosphere. The atmosphere of Biosphere 2 was not exchanged with the outside atmosphere.

Biosphere 2 continues to recycle all human and animal wastes. This is the first time complete waste recycling has been accomplished in a biological life support system.

Biosphere 2 continues to recycle all its water using a sophisticated system with over 20 subsystems. This maintained the wide diversity of water quality required--from the saltwater of ocean and marsh systems, to the rainwater needed by rainforest, savannah, desert, and farm--to the high purity levels required in drinking water.

Bioaccessions research during the transition

Teams of scientists conducted surveys to locate, affix a permanent number tag, map, and measure for biomass studies, all perennial plants in the wilderness blames and Intensive Agriculture Biome (IAB).

Plants introduced into Biosphere 2 before the first mission were recorded as alive, dead, or not found and new recruits were tagged and mapped as well.

Some plants were sampled and weighed to generate equations for biomass estimates.

Voucher specimens have been and are being collected to provide a complete record of Biosphere 2 plants. The herbarium is housed in the Biospheric Research and Development Center.

All data, such as biomass measurements and field notes, are entered into the bioaccessions database.

A second set of repeat photographs has been taken to document ecological community changes since the beginning of the closure experiment.

From these transition activities, SBV will look at reproductive success, mortality, and productivity. The data will be analyzed to see how original plant populations placed in Biosphere 2 adjusted to unique conditions in this closed system and how various eco-communities have changed.

Soils

Over 300 new soil samples from various soil depths were collected for archival storage. These, when compared to the original samples, provide information on three years of soil changes in the over 30 different soils originally placed in the system, and will be analyzed using a range of chemical and physical tests to track soil changes since installation in Biosphere 2.

Representative cores of soil material for root density analysis were collected to estimate the increase in underground biomass. These will be compared with root cores taken in the year before closure. Half square meter test pits were excavated in the lowland rainforest and ginger belt to quantify root development, layer by layer, in the soil horizon.

There has been extensive sampling of the soils of the JAB, to closely monitor this soil's development. Interactions between the irrigation water and soil chemistry will be closely monitored to understand more of these soil processes.

Wilderness soils have been examined closely for evidence of soil differentiation and maturation. For example, caliche (an impermeable layer of calcium carbonate) has started to form in some of the desert soils, and a dark-colored organic and clay-rich surface layer is becoming noticeable in certain soils.

Integrated pest management

All insects in the IAB were surveyed by Dr. James Litsinger, Agricultural Systems Consultant.

Predators for mites and mealy bug, cockroaches and pillbugs were introduced.

A complete survey of the nematode population was carried out by Dr. Michael A. McClure, Professor of Plant Pathology at the University of Arizona. The results will be used to guide further treatment of nematodes.

Some experimental work was carried out with Dr. Michael E.Stanghellini, Professor of Plant Pathology, University of Arizona, on the treatment of pithium fungus using beneficial bacteria.

Agriculture

40 geckos and 50 toads were introduced to help manage cockroach populations in the JAB.

Several new plant species were introduced for testing in the system on the advice of Dr. Richard Harwood, Chairman of Sustainable Agriculture, Crop & Soil Sciences Department, Michigan State University. These include shade-tolerant rice varieties from monsoonal tropical countries; shade-tolerant, starchy root crops such as yams and taro; new grain varieties such as short-stemmed barley and millet; and high-vigor sorghum varieties.

Planting areas in the lower IAB were increased in size and the planters were improved.

Supplemental lighting, using high-pressure sodium lamps, was added to the agriculture area to help sustain crop production during low-light periods.

Alterations to the planting layout were made to maximize efficient use of incoming light.

The goats and chickens proved to be excellent candidates for the Biosphere 2 farm and will continue as part of the agriculture system.

Rainforest

The rainforest more than doubled in size--some trees increased over 400 percent in biomass since original planting in 1990.

The rainforest strategy of thick gingerbelt and fast-growing trees to protect sensitive jungle plants has worked. Growth was so rapid (with some three dozen 45-50 foot trees after the two year closure) that we are now in the second phase of a planned succession. Thirty of the fastest growing trees (leuceana) were carefully cut down during transition to allow more light for mature rainforest species.

With advice from Dr. Michael Balick, Director of Economic Botany at the New York Botanical Garden and Dr. Ghillean Prance, Director of Kew Gardens, the rainforest was enriched with food producing plants. Species include bananas, tropical fruits, and starches.

A meticulous resurvey of Biosphere 2 was carried out by teams of researchers: all originally surveyed plants (some 7,800) were remeasured. New plants were tagged. Analysis of this data (now being entered in our computer database) will document in detail how various blames change as they grow--invaluable data for understanding basic ecosystem dynamics and restoration ecology.

With new plants established by natural reproduction and additional transition planting, our survey tags now number 11,000.

Ocean

All hard and soft corals were mapped under direction of Dr. Phil Dustan, Department of Biology, College of Charleston and Dr. Judy Lang, coral reef biologist, Texas Memorial Museum, during transition. There are 814 colonies of hard corals. and 173 soft corals.

Corals have reproduced during the two years and 87 baby coral colonies were identified.

Individuals representing 34 species of invertebrates and vertebrates were introduced to the ocean system along with injections of plankton, zooplankton and algae. Ten of these species are new to the ocean and were added to enhance ecological diversity.

Marsh

A pioneering study comparing ecological dynamics of mangrove species in the Everglades marsh and the Biosphere 2 marsh is now underway as part of a Ph.D. program of Matthew G. Finn, a doctoral student at Georgetown University. The dissertation includes studies of leaf litter and decomposition rates, water chemical analyses, environmental parameters, light spectral analysis, and species growth, distribution and diversity. (Finn will coordinate the execution of research projects within the system during Mission 2.)

The black mangrove, oyster bay and fringing island red mangrove ecosystems maintained a pure mangrove character and increased biomass by approximately 300 percent. The resurvey found very low mangrove mortality (less than 5 percent). Mortality was confined almost entirely to very small plants which were probably shaded. Fish (striped mullet, killifish, pipefish, blenny) snails (coffee, littorine, melanin), (mangrove, fiddler, porcelain, mud) and oysters were introduced.

New woody species (such as pond apple, mahogany, slash pine, wax myrtle, holly, groundsel tree, cabbage palm, myrsine, bald cypress and Montezuma cypress, white and red mangrove, salt bush, wax myrtle, buttonwood and black hew) were added to the other three ecosystems of the salt and freshwater marsh.

Some submersed and floating vegetation and fish species (gold-spotted top minnow, Florida flag fish, least killifish) were added to the fresh marsh pond.

Desert/Savannah

The two-year closure saw a dominance hierarchy emerge in the desert and Savannah vegetation among plants that had been introduced in the systems in fairly equal numbers. This natural process reflects varying plant adaptability. The wilderness biome census has provided a much better understanding of characteristics that make a species successful in synthetic ecosystems.

Some woody species assumed different shapes from their typical forms in outside environments. In most cases this appears to be caused by vigorous growth in reduced light, in the absence of strong breezes.

The originally-envisioned desert area became more dominated by large and small shrubs, annuals and grasses. Abundant winter moisture and mild summer drought tended to favor these plants over those usually found in coastal desert open scrub ecosystems. The blame will be allowed to develop in this manner. The system has been enriched with more woody species and shrubs to broaden its biodiversity. True desert plants persist in some drier areas of the biome.

Cool season rainfall will be increased to assist this transformation, making the area similar to a "Mediterranean woodland," Australian "mallee," or California "chaparral." In addition, a variety of Mediterranean-type trees were planted in the sand dune area of the desert.

Control of vines, which luxuriate in Biosphere 2 conditions, is a task of biospherians working within wilderness analog areas: morning glory (Ipomea spp.) in the rainforest, passion vine (Passiflora edulis) in Savannah and rainforest, and Queen's wreath (Antigonon leptopus) and several others in the upper thornscrub. Morning glory is eliminated from the rainforest and passion vine from the upper Savannah. This allows these systems more incoming light and development of a richer understory.

Plants with stolons--runners which re-root as they contact soil--also did extremely well. These include several Brachiaria grasses in the Savannah and Atriplex (saltbush) species in the desert.

Since Biosphere 2 has limited space and resources, exuberance by one species threatens the demise of several others. The crew must, on occasion, act as "keystone predators" to maintain maximum biodiversity.

The upper and lower savannahs developed rapidly with many African acacia trees growing in excess of 20 feet since planting. The removal of passion vine has allowed enrichment of the upper Savannah with a wider variety of tree and shrub species: fruit-bearing types such as tamarind, guava, lychee and macadamia nut, and the Cola tree from Africa (which bears a caffeine-rich bean); and extension of the grass understory.

Entomology

During transition, the entomology team under direction of Dr. Scott Miller, Bishop Museum of Hawaii, and Dr. Jim Litsinger, surveyed the wilderness and agricultural blames for insects and other invertebrates.

Approximately one-third of the insect species introduced prior to 1991 survived. Exuberant population growth by ants appears to be a direct cause of population decline of other insect species. This phenomenon is similar to what has been observed on oceanic islands. Insect species that did well are those that have juvenile stages protected from ant predation.

The best represented insect orders are the Orthoptera (cockroaches, crickets, katydids); Homoptera (leafhoppers, planthoppers, aphids, scales, mealybugs); Diptera (flies); and Hymenoptera (ants).

Pollinator species, in particular honey bees, are being reintroduced into Biosphere 2.

A special study of the ant, Paratrechina longicornis, has been initiated by Dr. Diana E. Wheeler, Associate Professor of Entomology, University of Arizona, to study the behavior of these insects that have distributed themselves throughout the Biosphere.

Engineering

From trace gas measurements of the atmosphere from May 1992 to August 1993, the average leak rate was approximately 11 percent per year. This world record low leak rate for a large closed ecological system (30 times lower than the Space Shuffle leaks) has enabled new observations such as the slow oxygen decline, sharp diurnal and seasonal carbon dioxide cycles, and the behavior of various trace gases in diverse, functioning ecological systems. The transition period has afforded the opportunity to locate and repair several minute leaks that were detected during the two-year closure. This is an ongoing program that will continue in the future to reduce the leak rate even further.

A concrete sealer is being applied to the exposed basement concrete to block the absorption of co2.

Technical Upgrades

Changes in technical systems, designed on the basis of the two-year shake down mission, were made during transition to enhance performance of both mechanical and computer systems. These changes included installation of 20 ocean skimmers, 200 lights in the JAB, and a new computer controller system to automatically manage all environmental parameters.

The original design of ocean scrubbers, an algae-based system to remove nutrients accumulating in the ocean through natural processes, proved inefficient during the first two years. These scrubbers were replaced with 20 skimmers which remove nutrients through an aeration and foam-removal process. These skimmers have already effected an improvement in ocean water quality, critical for coral reef health.

The addition of artificial lighting in the IAB will boost crop production during winter months significantly. Two unprecedented cloudy winters during the past two years, 1991 and 1992, reduced crop production below expectations. This extra lighting will help insure adequate food production.

The environmental computer control systems performed adequately during the two-year closure, maintaining required climates in the various biomes. However, this system was redesigned to reduce energy costs and allow controls of systems to be managed from outside as well as inside the Biosphere 2 system.

Biospherian Operations

For the last four months, the new crew has been training inside the Biosphere. They are now undergoing their final training period which consists of a series of one-week test closure periods where they live inside the Biosphere and operate it as if under closure conditions.

Although the system of operation and crew time allocation will be very similar to the first two year period, actual operations are projected to take less time due to technical improvements, giving more time for data collection and other research-related tasks.

Biogeochemical Studies

Oxygen study
The major atmospheric observation of the two-year closure was the decline of oxygen. This was definitively traced to a two-step process of oxygen loss to soil organic matter producing CO2, plus the CO2 being captured by structural concrete to form calcium carbonate. Measurement of the carbon-12/carbon-13 isotope ratio in several parts of the system was the key to confirming this evaluation. The success of this investigation demonstrates the power of a closed system as a tool to trace pathways of matter in ecological studies.

New Studies

Discussions and preliminary studies are underway which may help us better understand sources and sinks of trace gases found in Earth's atmosphere. Because Biosphere 2's glass roof admits no ultraviolet radiation, which in Earth's stratosphere impacts many trace gases, the closed facility gives an opportunity to isolate biological sources and sinks of gases such as methane and nitrous oxide in the absence of these other reactions.
Because of its higher CO2 levels, Biosphere 2 can provide evidence which may confirm or refute hypotheses that have been advanced regarding isotope changes in plants grown in higher CO2. Studies are underway that use Biosphere 2 conditions as a tool in understanding past geologic periods when CO2 was thought to be at higher levels.

New research projects initiated

Atmosphere studies
Professor Reinhardt A. Rasmussen, Oregon Graduate Institute of Science and Technology, Beaverton, Oregon, a world-renowned expert in measuring trace gases in Earth's atmosphere, has begun an intensive study of both technogenic gases (produced by technical systems) and biogenic gases (produced by living systems) in the atmosphere of Biosphere 2. The closed system allows Dr. Rasmussen to study the dynamics of biogenic gases from plants and soils in a unique way, not possible in any other setting. He has identified some 100 different major and trace gases, predominantly biogenic, in the Biosphere 2 atmosphere. Of special interest are the greenhouse gases methane, nitrous oxide, and carbon dioxide. These gases are especially important to understand because, as a result of their buildup in Earth's atmosphere, they play a role in global warning.

Modeling
Professor Howard T. Odum, Department of Environmental Engineering Sciences, University of Florida, Gainesville, currently has a graduate student working on a model of carbon cycling and biospheric energetics in Biosphere 2. He will add a new graduate student in 1994 whose focus will be on the overall global metabolism of Biosphere 2. This study will utilize daily and seasonal records of oxygen, carbon dioxide, humidity, rain, and light data from the Biosphere 2 database to calculate the overall system metabolism. This includes determination of plant photosynthetic efficiency, and the relationship between respiration and water loss in plants along with sophisticated measurements of light reflected from plant leaves. These light reflectance measurements will help gain an understanding of the water budgets of the Biosphere in relation to its overall metabolism.

Medical
Dr. Roy Verdery of the Arizona Center on Aging, Department of Geriatrics, University of Arizona will carry out sophisticated blood lipid analyses on the new biospherians before, during and after Mission 2. There is great medical interest in comparing these studies with lipid behavior in other calorie-restricted experiments. From the standpoint of the growing science of biospherics, there are interesting possibilities that closed system research gives us new tools to investigate whether physiological and/or psychological stress will produce recognizable effects on observed lipid patterns. Also, these patterns may allow us to characterize healthy dietary restriction and provide additional signals for the onset of malnutrition.

Video studies
An overhead video camera has been installed in the desert to use time lapse imagery to monitor changes in above ground desert plants.
Two video cameras have been installed over the ocean to monitor change in water clarity and community structure using time lapse imagery.
An underwater video camera has been installed in the ocean to monitor behavior of reef fish and invertebrates.

Soil research
A new research initiative in collaboration with Dr. Alvin Smucker of Michigan State University using "mini rhizotrons" that employ a tiny video camera will allow us to monitor root growth and competition. Ten underground tubes are being installed as a first experiment in the sand dune of the desert blame where real-time monitoring will occur and directly image competing root systems of desert trees, shrubs and grasses. This is of special interest because of the elevated CO2. One of the concerns about rising CO2 in Earth's environment is how it may change ecosystems by favoring growth of woody plants over grasses, for example. We will see if this is true in Biosphere 2 using the revolutionary rhizotron cameras.

Soil stations

Four soil stations were constructed in the wilderness biomes. These stations are carefully designed to monitor soil moisture content, gas composition, and temperature gradients throughout the soil column. These will allow us to more closely track soil processes and conditions.

March 6, 1994 Mission 2 Experiment

Beginning on March 6, 1994, Space Biospheres Ventures will launch Biosphere 2 as the first laboratory for the studies of biospheric and ecological science and the development of environmental technology. New operating procedures will allow visiting scientists to go into Biosphere 2 to conduct research on specific projects in a way not possible before. This is a result of knowledge gained from the successful first two year "Shakedown Cruise," and technical improvements implemented during the five-month transition period.

March 6 commences a new phase where Biosphere 2 is launched in its 100 year mission. Baseline operations will be managed by a rotating technical and resident crew which will enable various visiting scientists, managers, technical personnel and environmentalists to utilize Biosphere 2 facilities for short term durations. During the first 120 days, the resident crew will include Norberto Alvarez-Romo, Vice resident of Mission Control, and Director of Cybernetic Systems as the Biosphere 2's first visiting manager. At the third and sixth month intervals, a physician will perform a "house call" checkup visit on all persons inside. After the initial stay of Alvarez-Romo, other scientific, technical or environmental visitors will be eligible to enter Biosphere 2 for periods which will vary in duration.

Alvarez-Romo will establish and implement the protocols for the Biosphere 2 laboratory. He will also focus on enhancing the systems required for a "paperless society" (e.g. computer hardware, software, and communication systems). As the first "visiting participant," he will work with the staff of Mission Control to work out details for shorter term participants.

Unlike the initial two-years, there will not always be a resident physician inside Biosphere 2. Resident crew health monitoring and maintenance is being supervised by Harvey Meislin, MD, Professor and Chief, Section of Emergency Medicine, University of Arizona Health Sciences Center and his staff. The resident crew includes an EMT (Emergency Medical Technician) who monitors the crew's vital signs weekly. Dr. Meislin will go inside Biosphere 2 at three-month intervals to conduct medical examinations.