This week in the Planet Earth Podcast: how browner drinking water presents problems for the water companies; the effect of street lighting on bats and their commuter routes; and how ultraviolet light makes plants emit methane.

• Brown water, bats and streetlights, plant methane - Naked Scientists Science Podcasts and Science Radio Shows
• Brown Water - Planet Earth Online - Interviews
• Planet Earth Online - Water Repelling Soils - Interviews
• Planet Earth Online - Supercooled Water - Interviews
• Planet Earth Online - Measuring Groundwater - Interviews
• Metallurgy - Metals at the Molecular Scale - Podcasts