The Potsdam Biosphere project with its Naturerlebniswelt (Nature Exploration World) offers a unique off-work experience where plants are the central focus of attention.
Plants dominate our everyday life in various ways. Without them, there would be no life on earth. Everyday we use plants that grow in distant continents.
With this “Noah's Ark for Plants”, the architects of the Biosphere recount the fascinating history of plants and their significance for human beings. A series of “scenes” or environments affording different levels of participation involve the visitor actively and emotionally in the story of the development of the plants as we know them today.
A visit to the Biosphere is an informative, educational and entertaining journey through plant development in time and space, giving insights into the Earth’s deeper strata, the marine underworld, and the green roof of our tropical rainforests.
Biosphere is an “edutainment-exploration” model that raises environmental awareness and brings home the pressing need to protect plant life to ensure the survival of mankind.
The whole project started when the Client called a competition to build a flower pavilion that could subsequently be turned into a biosphere.
The site is in Potsdam near Sanssouci, the palace of Frederick the Great. Historically Potsdam has long been home to a collection of exotic gardens and architectures, with a Dutch quarter, a Russian colony of log houses, Schinkel’s Italian villas, the Chinese Tea House and Lenné’s picturesque and baroque gardens.
Potsdam was the seat of Prussian military power. Bornstedter Fields, the site of the Biosphere, was a parade ground for the Prussian military and later used by the Nazis for army exercises. After the war, the Soviets occupied the site and criss-crossed it with a series of earthen berms, or banks, to enclose and protect their barracks. This raw, defensive landscape was the formal conceptual basis for the competition proposal. It is now being transformed into a park for a Horticultural Show.
Rather than construct a greenhouse similar to Paxton’s Crystal Palace (an articulated glass and steel structure lying on a flat ground plane), the designers decided to extend the existing earth mounds to form an artificial valley running east-west, a solution that both complied with urban planning requirements and generated the form of the new pavilion.
The sunken ground plane allowed reduction of overall building height. The displaced earth was used to create new banks. Excavation produced a building that is in proportion to the earth mounds and does not obstruct views of existing historical monuments: the Pfingstberg and the Ruinenberg. Indeed, the Biosphere’s walls generate a visual alignment with the Pfingstberg monument.  
The Naturerlebniswelt is presented as a valley segment in a tropical forest. The valley is traversed its full length by a stream running through a geometrically placed basin. Passing through areas of dense foliage interspersed by clearings, the visitor experiences at first hand the changing character of a tropical forest.
A carefully designed path leads him continuously upwards towards the light. It winds its way along planted inclines that allow sweeping views of tropical vegetation not possible on the flat. Mainly in concrete and stone, the path is interrupted in places by wooden footbridges across water or over the stream.
Special viewing stations along the way offer views of the “scenes” or environments, some of which can be accessed directly via side paths.
Another smaller path, designed for the more adventurous, winds through the dense vegetation away from the main flow of visitors. At the western end of the Naturerlebniswelt, an opening in the soil leads to a media laboratory. This lab is located beneath a tropical pond, which the visitor will discover later on in his visit. From here the walkway continues across footbridges through the variegated array of vegetation that makes up the forest canopy.
The wide spans between embankments and their considerable elevation create a striking sense of space. To the north, the Naturerlebniswelt is a dense tropical forest, built on several layers that run southwards like corridors between the paths. The vegetation gradually thins to leave single-standing palm trees and/or other canopied species in the most southern clearings and  banks.
The stream is the Biosphere’s design backbone. It flows from the tropical pond at the top down to the mangrove swamp at the bottom. It creates several cascades on its downhill course as it falls over sudden drops. Before flowing sluggishly into the mangrove swamp, it is dammed up to create a small lake and down-stream flood plain.
The tropical clearings have been developed following natural mechanisms, i.e. with fallen trees forming a framework habitat for the diverse tropical flora.
As in nature, epiphytic (non-parasitic plants living on trees), bromeliads (plants of the Bromeliaceae family with short stems and lance-shaped spiny leaves) as well as orchids, creepers, perennials, bushes and saplings gradually take over the habitat.
Plants are characteristically layered in “storeys” with epiphytes settling at different levels. The whole system is in equilibrium, with plant growth and death finding its natural balance thanks to the wide variety of vegetation introduced. The various plants are represented at the various stages of their growth.
Layering:
1st floor:
Emergencies (plant outgrowths) projecting beyond the canopy; free hanging climbers. Swietenia mahagony.
2nd floor:
Tree canopy, old trees with epiphytes, free hanging climbers, Pouteria campechiana, Syagrus romanzoffiana, Passiflora.
3rd floor:
Low trees with slender crowns, tree ferns, epiphytes on tree trunks, trunk climbers, Philodendron bipennifolium, Cycadaceaen.
4th floor:
Bushy plants, ferns, new tree growth Dichorysandra thyrsiflora, Nephrolepis.
5th floor:
Herbaceous plants,  rain forest seedlings Maranthaceaen, Dieffenbachia.
Ground level:
Rotting plant residues, bacteriae, mushrooms, parasites.
Niddulatium scheremetiewii.
Staging.
Information and vantage points or stations are located on path bends. The path has been widened at intervals to create “scenes” or view points. The first of these is right at the start, on the way to the waterfall. Visitors find themselves on a terrace overlooking a planted embankment. The path leads down and around the water pool at the lowest point and continues under a rocky overhang where walkers will just about keep their feet dry.
Station 1: In the dark, dank mangrove swamp.
Mangroves grow in swampy water. It is damp, dank and humid. Plants growing on small ledges of rock protect visitors from the splashing waterfall while they get a close-up view of a mangrove swamp.
Scene A: A thunderstorm in the mangrove swamp.
Once on the rock terrace, visitors come to a station where measuring instruments and touch-screens provide information on climate and weather. The mangrove swamp now becomes even darker as a thunderstorm brews, giving way to a short heavy downpour.
In the mangrove swamp: View from the footbridge.
The footbridge through the mangrove swamp allows visitors a close view of the plants with their bizarre stilt-like roots. Long spear-like green roots – new plants sprouting in trees – can be seen at close quarters.
Station 2: The struggle for light.
Strategies and adaptations.
Leaving the swampy area, the path now returns to dry land. Light is still scarce, however, for we are still at the bottom, underneath various layers of tropical plants that shut out the sun’s rays. At the second station, visitors learn how plants vie with each other for a place in the sun and how astute they are at adapting to unfavourable conditions.
Travelling the Naturerlebniswelt:
The watercourse.
The path twists down the slope underneath the tree canopy to a small stream forming the inlet to the mangrove swamp. Large boulders, smoothed and rounded by retreating Ice Age glaciers, flank and split the watercourse.
River-bed.
Footbridges span the stream.
The boulders create areas of still and swirling water. It rushes and glistens as it cascades over small waterfalls.
Everywhere the vegetation is lush.
A step change.
Plants now become enormous. A bamboo clump projects its powerful shoots upwards; ferns no longer grow close to the ground but form massive trunks over which they spread their enormous fronds. Many other strange tropical plants now come into their own and assert their place.
Station 3: Propagation and sexual reproduction.
Here the path forms a dam close to a sandbank.
The watercourse branches out into several tributaries. The more inquisitive visitor can use the drift-wood as stepping stones onto the floodplain.
This dynamic, constantly changing habitat is continuously colonised by a wide variety of plants. The strategies of vegetative and generative propagation are the themes of this station. The rhizomes, or underground stems, of grass plants and the enormous flower-seed heads of Gunnera mannicata vividly illustrate nature’s propagation powers.
Scene C: Path and watercourse. Detail.
The path is now an effective dam behind which a small lake has formed and tropical plants float. Water seeps out through narrow grooves on the path’s surface, gushes over the edges or passes under culverts to continue its course through the sandbank.
Station 4: Bionics. Plank buttress trunk and termite colonies.
Along the embankment, visitors can inspect a termite colony. Nature’s building techniques are illustrated at this station with the plank buttress trunk, a natural system of reinforcement that man has put to good use in structural, electrical engineering and many other fields.

Cristiana Ruspa