Soil-particle selection by the mound-building termiteMacrotermes bellicosuson a sandy loam soil catena in a Nigerian tropical savanna

Abstract

Many species of termite (Isoptera) build their nests inside mounds because a mound has direct and positive feedback effects on the termite colonies through the maintenance of humidity and protection of the population from enemies, e.g. ants (Jouquet et al. 2006, Korb 2003, Noirot & Darlington 2000). Soil manipulation by termites (Isoptera) for mound construction is of particular interest for many researchers in terms of pedogenesis of the tropics (Lavelle et al. 1992, Lobry de Bruyn & Conacher 1990). The termites select soil particles according to ecological requirements such as water availability (Jouquet et al. 2002, 2007) and improve soil structural stability by means of application of clay particles and saliva/excreta (Fall et al. 2001, Jouquet et al. 2004). The nest-building activity of the termites inevitably causes regional translocation of soils (Bagine 1984, Holt & Lepage 2000) and distinctive patches in local ecosystems, which contributes to ecological diversity (Lavelle et al. 1992). This is the reason why termites are regarded as an ecological engineer (Jouquet et al. 2006). Soil-particle selection by the termites, however, has not been fully explored in relation to diverse ecologies and landscapes in Africa.

The influence of the mound-building termite (Macrotermes bellicosus) on soil clay mineralogy

“…1) support Mahaney et al (1999) and Ketch et al (2001), who found only subtle differences in clay mineralogy between the mound structures and adjacent soils. These data represent a contrasting evidence to that of soil particle distribution data in Table 1 that showed substantial enrichment with clay particles in the mound structures relative to the adjacent natural soil horizons (Abe et al 2009a(Abe et al , 2009b. Moreover, we found very little difference in clay mineralogy between the mound wall and the hive (Fig.…”

“…These samples include the external wall and main body of the hive in epigeal mounds of the fungusgrowing termite Macrotermesbellicosus (Smethman), Macrotermitinae (Termitidae), a very common termite species in the study area (Wood et al 1977, Collins 1979, 1981 and the near-surface (Ap2) and subsoil (Bwg3, Btg2 or Bt) horizons in a termite-free pedon at least 2 m away from the mound at three different toposequence positions: the valley bottom (08˚98 89 N, 06˚00 02 E); the hydromorphic fringe (08˚98 96 N, 06˚00 15 E); the well-drained upland plateau (08˚99 52 N, 06˚00 37 E) in a benchmark inland valley (see Table 1). As highlighted in the previous papers (Abe et al 2009a, 2009b, Abe and Wakatsuki, 2010, our sampling scheme has the following advantages: most previous reports simply compared the clay mineralogy of termite mounds (mostly the mound wall) with adjacent topsoils only, in spite of the fact that termites preferentially use subsoil material for mound construction (Lobry de Bruyn and Conacher 1990) and that the soil properties of termite mounds vary substantially according to structural units within the mound (Abe et al 2009a, 2009b, Abe and Wakatsuki, 2010.…”

“…4) in spite of the large disparity in particlesize distribution (Table 1). We therefore concluded that the mound-building activity of M. bellicosus affects soil clay mineralogical composition as a result of their preferential collection of fine soil particles ( 53 m) (Abe et al 2009b(Abe et al , 2012. These findings may indicate that clay mineralogy is not linked to the ecological requirements of M. bellicosus, although our previous studies (Abe et al, 2009a(Abe et al, , 2009b suggest that soil particle selection by M. bellicosus was based on the mound structures built, which had different ecological requirements such as water-holding capacity and structural stability (Jouquet et al 2002a(Jouquet et al , 2007.…”

“…This area is widely covered by siliceous or kaolinitic soils with a sandy loam texture (Abe et al 2006(Abe et al , 2007. These soils originated from Nupe Sandstone that mainly consists of Cretaceous sediments made up of semi-consolidated coarse grits, conglomerates, fine-grained sandstones, siltstones and locally occurring shales (Esu 1986 Soil samples used in this study were selected from those analysed by Abe et al (2009aAbe et al ( , 2009b and Abe and Wakatsuki (2010). These samples include the external wall and main body of the hive in epigeal mounds of the fungusgrowing termite Macrotermesbellicosus (Smethman), Macrotermitinae (Termitidae), a very common termite species in the study area (Wood et al 1977, Collins 1979, 1981 and the near-surface (Ap2) and subsoil (Bwg3, Btg2 or Bt) horizons in a termite-free pedon at least 2 m away from the mound at three different toposequence positions: the valley bottom (08˚98 89 N, 06˚00 02 E); the hydromorphic fringe (08˚98 96 N, 06˚00 15 E); the well-drained upland plateau (08˚99 52 N, 06˚00 37 E) in a benchmark inland valley (see Table 1).…”

Nutrient storage in termite (Macrotermes bellicosus) mounds and the implications for nutrient dynamics in a tropical savanna Ultisol

“…This soil is comprised of predominantly kaolinite and quartz in the clay and fine-sand fractions, respectively (Abe et al 2006(Abe et al , 2007, and is classified in the order Ultisols or sandy, kaolinitic, isohyperthermic Typic Kandiustults in detail (Soil Survey Staff 2006). M. bellicosus, the target species of this study, is one of the dominant termite species in the study region and often builds large epigeal mounds that display various types of cathedral shape (Collins 1979(Collins , 1981Korb 2003;Abe et al 2009aAbe et al , 2009b.…”