The impact of mine tailings on snouted harvester termites, Trinervitermes trinervoides (Sjostedt) (Isoptera: Termitidae), in the Vaal river region
Year: 2012
Type: dissertation
Abstract: Mining activities are well known for their negative effects on the environment and \nanimals, due to the deposition of large volume of wastes in the form of tailings on \nthe soil. These wastes or tailings contain high levels of heavy metals, sulphides \nand cyanide. Heavy metals are one of the most persistent pollutants in the \nenvironment and have been shown to bioaccumulate in animals. The purpose of \nthis investigation was to evaluate the impact of mine tailings on the snouted \nharvester termite, Trinervitermes trinervoides, inhabiting the Vaal River region. \nThese termites play a significant role in the food chain as they provide a proteinand \nenergy-rich food source to numerous predators therefore any bioaccumulation \nof heavy metals may adversely impact the food chain. Three aspects of the termite \nbiology was studied, namely, the density and distribution of the termite mounds, \nthe temperature profile of the mounds and the heavy metal content of the termites, \nmounds and surrounding soil. Three sites were chosen in accordance to their \nposition relative to a tailings dam with the furthest site being the Control site. The \nmost contaminated site and site closest to the tailings dam (AEL site) had the \nhighest termite mound density, followed by the least contaminated site (Control \nsite) and then the intermediately contaminated site (West Complex). The AEL site \nhad many incipient mounds but few large mounds indicating that although there \nwas a high turnover of new mounds, the longevity of these mounds was low. \nHigher densities at the AEL site may be explained by the water table being closer \nto the surface as a result of the tailings dam, allowing the termites easier access to \nwater and hence a more favourable environment within the mound. The centre \ntemperatures of the mounds at all three sites were kept constant on a monthly \nbasis but fluctuated on a seasonal basis. The West Complex site had the highest \nand most variable centre mound temperatures. The average heavy metal content of \nthe surface layer did not differ significantly from the average heavy metal content \nof the mounds at the AEL and West Complex site, indicating that the termites are \nnot making heavy metals more bioavailable to the environment. The termites at \nthe AEL site had the highest levels of Cu and Zn out of all the sites and \naccumulated these metals to levels toxic to mammals. Alates (a major food source \nfor many animals) however, did not accumulate any heavy metals therefore it is \nunlikely the food chain is being negatively impacted by the termites. From this \nstudy there is no indication that the snouted harvester termite density or behaviour \nare being impacted by the tailings dams
Author: Megan Ann Field
Language: English
Subfield: Health, Toxicology and Mutagenesis
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W39260049