The area of the KAIG botanical garden will be 160 hectares. It will be located in the middle of the desert, southeast of the capital of Saudi Arabia - the city of Riyadh, whose name means "city of gardens and trees."
In 2007, an architectural competition was held for the design of this garden - it was won by the British tandem of the architectural bureau Bartom Willmore and the engineering company BuroHappold. And now, according to this project, the construction of a grandiose botanical garden has begun, in which you can see plants that existed 400 million years ago - here models of disappeared trees, shrubs and flowers will be interspersed with living plants.
The KAIG garden will house research institutes, a seed fund, restaurants, hotels, a theater, a butterfly enclosure, a poultry house and a labyrinth. But its "heart" will be the building of the Paleobotanical Garden - a gigantic structure that will consist of two adjacent greenhouses in the shape of a crescent. The area of this garden is 10 hectares, that is, in size it is comparable to fifteen football fields.
The paleobotanical garden will focus on the topic of climate change and, in particular, how plants change over different eras in this particular corner of the earth. Inside, the indoor garden is divided into several zones with completely different climates. Each of them will recreate the flora of the region for a certain era, starting with the Devonian period, which began about 400 million years ago - then the height of local plants did not exceed the level of a human knee.
The garden of the Carboniferous period is planned to be populated with giant models of half-meter dragonflies, two-meter centipedes and nine-centimeter cockroaches. It is being replaced by the Jurassic period (the age of dinosaurs and ferns) and a Cretaceous garden dedicated to flowers: some of them have survived to this day - these are lotuses and lilies. Then the visitor will find himself in the Cenozoic era, which began 65 million years ago and continues to this day.
After that, the visitor enters the crescent courtyard - the Wadi outdoor garden. Here, without the help of special equipment that creates an artificial environment, the current nature and vegetation of the peninsula is presented.
Two gardens are allocated into a separate group - the Pliocene Garden and the Garden of Choice. They will be located at the end of one of the crescents. In the Pliocene Garden, the nature of this era will be shown: the riverbed and woodland will be recreated. The Pliocene began just over five million years ago and lasted for about two and a half million years. It is believed that it was in this era that Australopithecines appeared and died out, and people (genus Homo) appeared. The final point of the journey through the gardens will be the Garden of Choices, where the visitor will be able to see with his own eyes the possible scenarios for the development of local nature - as climate changes continue and when they stop - depending on the choices that humanity can make now.
Thus, it is planned to simultaneously demonstrate different climatic conditions under the roof of the Paleobotanical Garden. Therefore, materials and structures that are compatible with various environmental conditions will be used here.
The base of the "crescents" will consist of several reinforced concrete frames with a height of eight meters and a length of 55 to 75 meters. Each of them must support the structure of a metal-framed arched roof. When designing greenhouses, special attention was paid to thermal expansion and shrinkage of materials, so the number of required moving parts and joints is minimized.
The height of the building is 40 meters. It is planned to use pneumatic membrane cushions for the roof.
ETFE (ethylene tetrafluoroethylene) enclosed in aluminum profiles and supported by a lightweight structure. The extraordinary strength and durability of the ETFE system will allow it to be used as a light-transmitting enclosing structure.
ETFE was invented by DuPont over forty years ago for the space industry. It is not affected by ultraviolet radiation and atmospheric pollution. The extremely smooth surface is easy to self-clean in the rain.
To provide resistance to external loads and thermal insulation, air is drawn into the EFTE cushions under low pressure. The use of cushions made of EFTE membrane for facades-roofs of this huge structure with thousands of plants is justified by the fact that the material perfectly transmits light and at the same time, unlike glass, the cushions have very high thermal insulation properties, which together with the ability to integrate elements into the EFTE structure changing the light transmittance during the day will significantly reduce the cost of lighting and air conditioning greenhouses.
The KAIG Botanical Garden is to become a large educational and research center specialized in the study of climatic and ecological processes, therefore, the theme of sustainable development and resource conservation is given a special place by its creators. The energy needed for the project will come from solar panels, wind turbines and thermal power plants. Rainwater (it rains here in winter and spring) is planned to be accumulated in underground reservoirs, purified, used for irrigation and then reused.
