Termites and Forest Ecosystems

Termites and Forest Ecosystems

Nitrogenous products of termite origin may enter and be distributed within the ecosystem in several ways. Adult termites are able to pass nitrogen-containing compounds to their young by trophallaxis. This transfer can occur from stomodeal food, proctodeal food, and salivary secretions (Waller and La Fage 1987). Stomodeal food is food that is partially digested in the crop of the donating termite which is regurgitated and fed to a recipient termite. The dependent castes receive nutrients and digestive enzymes in the process. Although this behavior is not common among termites (La Fage and Nutting 1978), it represents a possible mode of distribution of nitrogen containing compounds to colony members. Proctodeal food is transferred from the anus of donor termites. This food is also partially digested and differs from feces (Waller and La Fage 1987). Flagellate protozoans and other gut symbionts are transferred along with proctodeal food. Saliva is rich in lipids and protein (La Fage and Nutting 1978) and is also fed to dependent castes (Waller and La Fage 1987).

Another way in which nitrogen may enter the ecosystem is through direct deposition onto soil. Salivary secretions mixed with soil and wood particles are used by termites to build tunnels and galleries. Most termite nests are made of carton which is composed of soil mixed with termite feces. These galleries, tunnels, and carton can extend far into the soil, and this close association to the soil offers opportunity for the nitrogenous compounds to adsorb to soil components (Wood and Sands 1978).

Finally, further N-distribution into the ecosystem by termites may occur through the seasonal dispersion during reproductive flights of winged adults called alates. Species differ as to the time of dispersal and number of dispersal events. In general, alates develop from workers or nymphs. At the appropriate time they fly away from the colony, form mating pairs, and generate new colonies far from the original nest site (Nutting 1969). Most alates fall victim to predation and other environmental factors. In this way, their complement of nitrogen is recycled in the form of food and detrital material (DeAngelis 1992).

References

DeAngelis, D. L. 1992. Nutrient interactions of detritus and decomposers. In: M. B. Usher, M.L. Rosenzweig and Kitching, R.L. (eds.) Dynamics of Nutrient Cycling and Food Webs. Chapman and Hall, London. pp.123-141.

La Fage, J. P. and W. L. Nutting. 1978. Nutrient dynamics of termites. In: M. V. Brian (ed.) Production Ecology of Ants and Termites. Cambridge Univ. Press, U.K., pp. 165-232.

Nutting, W.L. 1969. Flight and colony foundation. In: K. Krishna and F.M. Weesner (eds.), Biology of Termites, Vol. 1, Academic Press, New York, pp. 233-282.

Waller, D. A. and J. P. La Fage. 1987. Nutritional ecology of termites. In: F. Slansky, Jr. and J. G. Rodriguez (eds.) The Nutritional Ecology of Insects, Mites, and Spiders. John Wiley and Sons, New York. pp. 487-532.

Wood, T. G., and W. A. Sands. 1978. The role of termites in ecosystems. In: M. V. Brian (ed.) Production Ecology of Ants and Termites. Cambridge Univ. Press, U.K., pp. 245-292.