Visitors: Masks are required at all times when visiting Biosphere 2.
Mini Landscape Evolution Observatory (miniLEO) is a model landscape slope composed of granular basalt used to conduct small scale experiments to more clearly understand how elemental transport occurs during simulated rain events. For this experiment, rain events occurred three times a day in two hour increments at a rate of 30 mm/hr for 14 days to determine if exchangeable ions and target elements dissolve over time. An auto sampler collected the waterseepage every half hour at the bottom of the slope of miniLEO. Each seepage sample was tested or the amount of elements present in solution using ion chromatography and an aqueous carbon analyzer. The concentration of Total Inorganic Carbon decreased; however, there was an increase in concentration of Calcium and Magnesium, which may have paired with dissolved CO2 to form secondary minerals, Calcite and Magnesium Carbonate, respectively. Additionally, the presence of Potassium varied throughout the experiment; this may be due to the high affinity of ion exchange for Potassium. The concentration of Organic Nitrogen decreased due to various factors. This could be due to a greater percentage of denitrifying bacteria compared to the amount of Nitrogen fixing bacteria. Also, there was no vegetation to replenish the Nitrogen in the system. This project demonstrates the effects of nutrient transport through soils with emphasis on the role rain plays in soil vitality.