Task: Question Generation
Input (English): Background Paragraph: Precipitation in grasslands is equal to or less than evapotranspiration and causes soil development to operate in relative drought. Leaching and migration of weathering products is therefore decreased. Large amounts of evaporation causes buildup of calcium (Ca) and other large cations flocculate clay minerals and fulvic acids in the upper soil profile. Impermeable clay limits downward percolation of water and fulvic acids, reducing chemical weathering and podzolization. The depth to the maximum concentration of clay increases in areas of increased precipitation and leaching. When leaching is decreased, the Ca precipitates as calcite (CaCO3) in the lower soil levels, a layer known as caliche. 
Story: Two farmers had neighboring parcels of land. Bob had a nice parcel of old growth forest, while the other farmer, named Bill , had a similar sized parcel covered in grasslands.
Output (English): Which farmer observed decreased migration of weathering products in the soil?