Soil in the agricultural area of Biosphere 2 (1991-1993)

The agricultural area (intensive agriculture biome) of Biosphere 2 was star ted with a meter of alkaline soil with high organic content in 1990 and use d to support eight persons during closure 1991-1993. Wastes were recycled t o maintain fertility. Soils sampled at the end were analyzed for major and minor inorganic constituents and organic matter. C/N ratio was high (13:1 t o 17:1). Organic matter decreased 0.2 to 1.4% per year. With exception of h igh salinity developing in one plot and denitrification in the rice paddy, the soils at the end were functional in supporting crop production. (C) 199 9 Elsevier Science B.V. All rights reserved.