We have studied the ecotoxicity of three heavy metals, including copper, cadmium, and lead, to various species (e.g. green algae, moss, floating plant). A probabilistic risk assessment (PRA) was conducted to characterize the ecotoxicity of copper, cadmium, and lead in leaching water from ashes. The relative risk among three heavy metals was investigated using joint risk probability distribution curves, which were generated based on the distributions of exposure and acute toxicity data. The Pb risk was considerably higher than that of the other two heavy metals. The degree of the Pb risk was an object for mitigation, however the degree of Cu and Cd risks were judged acceptable. The moss Funaria hygrometrica tolerated to higher concentration of heavy metals in leaching water from ashes, however the cells were notably sensitive to their leaching water form ashes. PRA suggests that some leaching water from ashes have toxic-compounds (e.g. inorganic-compounds except copper, cadmium and lead, organic-compounds), and their toxic-compounds strongly affect to the moss F. hygrometrica.

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New localities of Riccia pubescens S. Hatt. are recorded in Tochigi and Ibaraki Pref., central Japan. The liverwort is similar to R. atromarginata, but differs in the sexuality, the size of spore and the length of cilia on surface of thallus. The liverwort is monoicous and has smaller spores (55-80 μm in diameter) and longer cilia (100-250 μm).

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Chemical structures of pungent, bitter and sweet substances from bryophytes and their bioactivity are discussed.

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