Cline of
heavy-metal
tolerance in Agrostis
Most plants are unable to grow on heavy-metal
contaminated
soils ("tailings") on the margins of abandoned
copper
mines. Cu++-tolerant forms of the grass
Agrostis tenuis
have been selected to grow on these soils [adult plants at
20~40m], but
are poorly adapted to non-contaminated soil [adult plants at 0].
Wind-borne pollen is carried downwind, such that the seedling
population at 60 ~ 100m downwind are more tolerant than the adult
plants.
Figure © Futuyma (1997) after
Macnair (1981);
Text material
© 2018 by Steven M. Carr