What pH are most lakes in Norway?

Answer 1

Most lakes in Norway are acidic. One report (see attached link) showed pH ranging from about 6.5 (slightly acidic) to 4.5 (definitely acidic). This is to be expected since most of the lakes receive runoff that flows through oak and pine forests where it picks up acidity from the fallen leaves and needles. Also note that pines grow best in acidic soil so their presence is a good indicator that the soil is naturally acidic to begin with so water flowing though that soil will become acidified. Also, rain is naturally slightly acidic since it dissolves carbon dioxide in the air to form weak carbonic acid. Of course anthropogenic sources can increase acidity somewhat but the dominant source of acidification of the lakes is natural, not man-made; the winds blowing over Norway mostly come from fairly uninhabited areas like the North Atlantic, Greenland, Northern Canada, etc, so there isn't much in the way of anthropogenic sources at those latitudes.