The response of 12 different plant materials and one mushroom to Mo and Pb mineralization along a 100-km transect in southern central Norway

Along a transect crossing the Oslo rift Mo and Pb mineralizations occur, among them the Nordli Mo and the Snertingdal Pb deposit. In total 15 different sample media (soil C and O horizon and 13 plant materials) were collected at each of 41 sites along a c. 100-km transect to the north of Oslo and analysed for 53 chemical elements. The responses of 12 different plant media (birch, spruce, cowberry and blueberry leaves and twigs; fern, horsetail and pine bark) and one mushroom (rufous milkcap) to the mineralization and lithological changes along the transect were studied. Most sample materials show a clear reaction to the mineralization, horsetail emerges as the plant that provides the strongest signal and milkcap is the sample medium least suited for mineral exploration. Birch and cowberry emerge as the best compromise for biogeochemical exploration in terms of signal strength and widespread availability in Norway. The uptake of many elements in the plants is strongly controlled, surprisingly fewelements indicate the major lithological changes along the transect, e.g. the presence of the Oslo Rift. Most plants react strongly to the presence of Pb mineralization, this can be due to direct uptake or to deposition of local soil dust but cannot be attributed to long range atmospheric transport.