Biocementation technology for construction of artificial oasis in sandy desert

摘要

Artificial oasis could be supported by the trapping and retaining rainfall water by impermeable layer of artificial material. In case of average annual rainfall in Arabian or Pakistani Deserts of 100?mm the watershed area must be at least 1000?ha to ensure rainfall water supply for consumption and irrigation in the artificial oasis of 100?ha area. Minimum cost for the sealing of 1000?ha of the sand slopes with 1?mm geosynthetic liner is about 112?mln Saudi Arabian Riyal, which could be not acceptable price for 100?ha of artificial oasis land. However, this cost could be diminished to 17?mln Saudi Arabian Riyal if to coat watershed slopes with 1?mm of biocemented sand crust using a low viscosity solution of biocement. Conventional cementation is cheaper but it cannot be used to make 1?mm sand crust because of a high viscosity of the cement suspension. The novel biotechnological method is based on the formation of the sand surface crust for water collection and transportation on the surrounding slopes. Most environmentally friendly biotechnology for this biocementation is aerobic biooxidation of cheap calcium formate or calcium acetate. Biocementation of the sand crust could be used to make a low-cost artificial desert oasis fed by rainfall.