A new American study on the impact of climate change on the retention of metals in the forests

Little Rock Pond
Green Mountains – photo © Brian W. Schaller

A recent study, undertaken by the Dartmouth College in the mountains of New England, has been published by the journal Plant and Soil[1]. Based upon a survey of metals (cadmium, calcium, copper, magnesium, manganese, potassium and zinc) concentrations in the soils of deciduous and conifer forests, in eight places of the Vermont’s Green Mountains (reaching 1,339 m) and New Hampshire’s White Mountains (culminating at 1,916 m above sea level).

It shows that the concentrations of the studied metals are significantly lesser in the soils under the conifers, as well as in their leaves. It has also been found that the retention time of most of these metals is much longer under the conifers than in the soils under the deciduous trees.

Mirror Lake
White Mountains – photo © Chemical Heritage Foundation

The climate change, by increasing the temperature and precipitations, is, at the present time, favouring the replacement of conifers by deciduous trees. This replacement is estimated to reach more than 70% in New England by 2085. This should lead to important changes in the distribution of metals in the soils and subsequently in the surface and subterranean waters, changes that could have some impacts on public health.

Once again, it shows that the impact of climate change on the mountains has far-reaching effects that are not completely known.

(HT)

[1] Plant and Soil, pp 1-16, First online: 23 January 2016, Influence of coniferous and deciduous vegetation on major and trace metals in forests of northern New England, USA, J. B. Richardson, A. J. Friedland.