There are currently an estimated 4,000 species (2,600 are taxonomically known) with about 2,000 species of termites or "white ants" found in 2/3 of the world's land but predominantly in grassland, savannah and forests in tropical and subtropical regions. In the drier tropics ((<800 mm rain per year) termites dominate the soil fauna. They have a complex social life in nests or mounds above or below the ground, each home to over 1 million termites.
In building their "cities", including the network of passages which may spread 20-30 metres beyond the mound, termites transport soil from lower layers to and above the surface soil level. Termite deposits are largely built from subsoil, which commonly have a lower organic matter and nutrient content than the surrounding undisturbed topsoil. This intermixing of soil layers and plant residues that they use as food has therefore a significant effect on soil formation and nutrient translocation within the soil layers. The mounds or nests which are produced disrupts crop production as termites tend to obtain surface residues from a wide areas of land and incorporate them in localised areas thus hindering the build up of a protective layer of crop residue mulch in croplands.
Termites generally feed on rotting woody materials and plant residues although some eat living woody material and sound deadwood. To help them digest this material they have an assortment of microbes in their gut with a different microbial flora found in different portions of the gut. Both prokaryotes and flagellated protists are found in the guts of termites although in some, the “higher” termites, typically lack the flagellated protists found in the “lower” termites, with the degradation of plant material entirely done by bacteria. Although the identification of some symbiotic gut microbes have been known for some time it is only recently with the use of molecular technology that a fuller understanding of the complexity of the termites gut is emerging (Hussender, 2010).
As they feed almost exclusively on wood and plant derived material, termites cause economically significant damage. However, as they possess a diverse range of organisms and many novel metabolic pathways to utilise their food sources, termites may provide novel genes for the biotechnology industries, energy sources such as hydrogen and biomass utilisation (Brune, 2007; Warnecke et al., 2007) as well as being a major source of methane and nitrogen-fixing.
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