Item

Abstract

Questions: Termite mounds of the genus Macrotermes are prominent features in
African savannas, forming nutrient hotspots that support greater plant diversity,
which is of higher nutritional value than the surrounding savannamatrix. However,
little is known about grass communities on and around mounds or how
the functional importance ofmounds varies across sites. Asmean annual rainfall
increases, savannas in southern Africa become increasingly dystrophic through
increased denitrification (including pyrodenitrification) and the leaching of soil
nutrients. The functional importance of mounds is concomitantly expected to
increase as the difference in foliar nutrient levels between mounds and the
savannamatrix increases.We tested this prediction on grass communities across
a rainfall gradient to: (i) determine the degree to which grass assemblages differ
between termite mounds and the savanna matrix; (ii) determine the spatial
extent to which mounds influence grass communities; and (iii) investigate
whether these patterns differ across savanna types.