Carbon and nutrient leaching from termite mounds inhabited by primary and secondary termites

Abstract

Termites concentrate nutrients in their mounds, which may reenter soil through leaching. We studied the effect of the grass-feeder and litter-forager termite Cornitermes silvestrii on soil solution chemistry. Free-draining lysimeters were installed below mounds of this primary termite, below mounds build by C. silvestrii but inhabited by secondary termites (mainly by Nasutitermes kemneri), and reference soils. The solution was regularly collected during a 1-year period and analyzed for dissolved organic carbon (DOC), phosphate, nitrate, ammonium and pH. The volume of drainage water was lower under the mounds than under the reference soil, and so was the flux of DOC and nutrients. Only nitrate concentrations were enhanced under secondarily inhabited termite mounds. Hence, an effect of the termite mounds on drainage water and soil nutrients through leaching is evident, but the latter only below older mounds with secondary termites.