AP Environmental Science 3.E: Carrying Capacity

Termites are social insects that are essential decomposers in tropical rain forest ecosystems. Termites may account for up to 95 percent of insect biomass in tropical rain forests. Termites consume vast amounts of dead and decomposing plant material, thanks to the work of mutualistic cellulose-digesting microorganisms that inhabit their guts. In addition to their roles as important decomposers, termites digest plant materials and directly contribute to carbon dioxide and methane emissions into the atmosphere. It is likely that, like many insect species, termites and their symbionts may be sensitive to changes in their microclimate caused by global climate change, especially with regard to temperature and humidity.

It has been observed that soon after a tropical rain forest is cleared, termite density increases to an estimated $6.8 \times 10^{7}$ termites per hectare. Thereafter, the termite population size decreases dramatically.

Why do the termite populations eventually decrease dramatically?