Environmental determinants of spatial pattern in the vegetation of Pb-Zn mines in southwestern Wisconsin

A closed turf community occurs in areas of finer soil texture, higher N and moisture levels and lower Zn concentrations. Open turf occurs on sites of greater environmental stress. Nitrogen mineralizaton rates are comparable between communities. Significant reduction of environmental stress occurs with advancing successional age. Soil moisture and total N increase with mine age, while Zn concentrations decline. Application of mulch to the open turf increased biomass, but no significant increase occurred after fertilization, so the factors limiting vegetation success in the open turf are probably related to the severe environment of the tailings surface. Fertilization produced a biomass increase in the closed turf, but many species were unresponsive to added nutrients, a behavior consistent with characterizing them as "stress-tolerant' sensu Grime. -from Author