The microdistribution of Agrostis tenuis on colliery spoil in relation to spoil chemical variability.
Abstract
Spoil samples were collected from 5 colliery spoil heaps in N. England. Relationships between the microdistribution of A. tenuis and 17 spoil chemical characteristics were investigated. On very acid sites (mean pH <4.0), vegetated spoil differed from bare spoil in having a higher pH, lower conc. of Cu and Fe and higher conc. of K. It was concluded that these differences influence the microdistribution of A. tenuis, although the factors also varied in importance in different regions of each site. On less acid sites (pH >4.0), there were no significant differences between vegetated and bare areas of spoil for any of the 17 characteristics measured. However, when the samples were divided into more homogeneous groups, certain acid toxic regions were revealed from which A. tenuis was absent. Unmeasured physical factors may have been more important than chemical factors in most of the less acid sites.