Nutrient recycling systems of Biosphere 2. Litterfall, decomposition, and wastewater recycling: results from the 1991-1993 closure experiment.
Important aspects of nutrient recycling in Biosphere 2 were plant litterfall/leaf decomposition in the terrestrial biomes and sewage and wastewater processing by a constructed wetland system. During the second year of closure, annual litterfall ranged from 1317 +/- 283 g/m2 in the lowland rainforest to 141 +/- 58 g/m2 in the desert sand dune area. Litterfall patterns followed different seasonal regimes in the biomes. Leaf decomposition averaged 90%/year in Biosphere 2, with the smallest leaf loss in the desert biome. For maintenance of soil fertility in the agricultural area, inedible crop material and domestic animal manure was composted, and human waste products and wastewater from people, labs, and domestic animals was processed in a 41-m2 constructed wetland. The wetland produced 1200 kg of fodder and remaining nutrients were returned to the soils via irrigation water.
Nelson
M
M
Institute of Ecotechnics, London, UK.
D018533:Biomass; D018556:Crops, Agricultural; D018504:Ecological Systems, Closed; D017753:Ecosystem; D004784:Environmental Monitoring; D008021:Life Support Systems / Q000295:instrumentation*; D018515:Plant Leaves / Q000378:metabolism; D014865:Waste Disposal, Fluid; D018505:Waste Management / Q000379:methods*