Nest structures of six termite species, four with epigeous (above-ground) and two with subterranean nests were analysed to
find out how their building and feeding habits could be related to their nests phosphorus status compared with control soils.
Termite nest structure was found to affect significantly the P status in savanna soils: mounds of the African
Trinervitermes geminatus and the South American
Nasutitermes ephratae (both grass-feeders) displayed a greater amount of available P, especially in the inner part of the nest, than the surrounding
soil. The abundant quantities of dead grass material stored in the mound can explain the available soil P increase. A similar
increase in P availability was also found for the soil-feeder
Cubitermes severus. In mounds of
Macrotermes bellicosus, on the other hand, there was a drastic increase in P sorption (and a corresponding decrease in available P) compared to
adjacent soils, which was attributed to the building strategy of this species.
M. bellicosus selected clay from subsoil to build its nest structure. The data obtained for the subterranean species
Ancistrotermes cavithorax and
Microtermes toumodiensis indicated also that there is an increase in P sorption in mounds when compared with associated topsoils. Consequently, the
nest structures of only certain termite species should be considered, and utilised, as a soil amendment in place of fertilisers.
This impact on the P cycle in savannas seems to be related to the termite feeding status and to the type of material utilised
in nest building. This should be taken into account before using termite nest material in soil fertility status improvement.
Keywords Termite nests - Savannas - P sorbing - P availability - Soil fertility