Physical properties of lacustrine sediments are good indicators of environmental changes in the physical conditions of lake-catchment systems. Lacustrine sediment data from Lake Biwa, Japan, suggest that the high mineral content of sediments correlate with the heavy rainfall events during the instrumental observational period. It is also shown that an increase in mineral content and a decrease in mineral grain size may correspond to historically significant earthquakes around Lake Biwa. Cross-spectral analyses indicate that temporal changes in the proxy precipitation (and/or discharge) (mineral content) may be closely related to the cosmic-ray-induced ionization (CRII) during the past millennia.