Australia: The Land Where Time Began

A biography of the Australian continent 

Termites in Tropical Savannas

Especially in the more arid regions, termites are prolific in the savannas of much of northern Australia. The cracking clay soils are the only parts of the Australian semi-arid tropics that don't have high number so of mound-building termites. Unlike the microbial activity that only operates in the wet season, termites operate throughout the year, though it means that microbes operate throughout the year, but in the guts of the termites, as it is actually the gut microbes of the termites that breaks down plants material, and also fix nitrogen. The result is that they are important contributors to the nutrient status of the otherwise nutrient-poor soils.

Research in the Townsville area has found that the 2 mound-building species of termites studied mineralised about 250 kg of carbon per year, about 10 % of the annual carbon turnover at the site. There were also subterranean termites at the site. They are believed to have contributed about 20 % of the carbon mineralised in the system, but the researchers were unable to asses their contribution. In areas where the soil is damp for most or all of the year the function carried out by termites is carried out by soil microbes. The niche vacated by the soil microbes for most of the year in tropical savannas is filled by the termites.

The decay of abandoned termite mounds in the Kakadu National Park, with the resulting release of nutrients to the environment, is increased by the activities of other fauna, such as burrowing vertebrates. In these abandoned termite nests the termites are replaced by other insects, small lizards, rodents, snakes, native cats and bandicoots.

Sources & Further reading

1. Mary E. White, Earth Alive, From Microbes to a Living Planet, Rosenberg Publishing Pty. Ltd., 2003