We characterised the soils and vegetation in 15 sets of four quadrats on and around mounds of Macrotermes annandalei (Isoptera, Macrotermitinae) on a plain of deep dystric clay over limestone in Deciduous Dipterocarp Forest in Northern Thailand. Termites have excavated the mounds from the deep calcareous substrate. The mound soils have darker subsoils, larger contents of clays and exchangeable cations, and higher pH values than the surrounding dystric clay loams. The thickets on the mounds are visually different from the surrounding Deciduous Dipterocarp Forest. They have few dipterocarps and are floristically similar to the regionally important Mixed Deciduous Forest. The clear visual differences are confirmed by floristic similarity, cluster, and canonical correspondence analyses for each of the tree, sapling and seedling size classes. The differences between the mound clays and surrounding red clay loams and the associations between soil and forest types are confirmed by ‘t tests’ and the significant correlations of the soil base status with the main floristic axis of the canonical correspondence analyses. Soil variability due to termites and other agents of pedoturbation can significantly contribute to short-range floristic and structural diversity in some dry tropical forests.

This study tested the hypothesis that the black rhinoceros browses more on termitaria than off termitaria vegetation due to elevated soil and foliar nutrient levels on termitaria. We investigated the role of termitaria in providing nutrient-rich forage for the black rhinoceros, by comparing the preference (selection ratio) for vegetation occurring on and off termitaria, and then testing its relationship with foliar nutrient concentrations. Soil nutrients, bite intensity, tree species diversity, vegetation density, canopy cover and basal area were also surveyed on and off termitaria. We sampled 25 termite mounds together with their corresponding control plots in Chipinge Safari Area, Zimbabwe. Soil and foliar N, P, K, Ca and Na concentrations were greater on termitaria than off termitaria, with approximately twice the concentration of these nutrients. Browse preference followed the between-site differences in soil and foliar nutrient concentrations, with higher selection ratios and bite intensities for vegetation on termitaria than off termitaria. Diospyros quiloensis was the most preferred browse species whilst Combretum imberbe, Kigelia africana and Strychnos innocua were the least. In conclusion, the black rhino preferred vegetation on termitaria to that in the surrounding matrix, and utilization of vegetation can be influenced by the soil substrate on which tree species grow.

Earth mounds are important determinants of vegetation pattern in savannas, acting as foci for establishment of woody plants. In the Kenya highlands, mounds formerly attributed to termites have recently been found to be Mima mounds produced by rhizomyid mole rats. We investigated Mima mounds on black cotton soils near Kenyatta International Airport and on brown clay soils between Nairobi and Thika. At Kenyatta Airport, mounds had loamier, more granular soils than intermounds, and contained small rocks that mole rats can move. At the site between Nairobi and Thika, mound soils were more friable, higher in pH, and lower in carbon than intermound soils. Data from this and other studies indicate that Mima mound soils are more favourable for plant growth than those of true termite mounds. Mound vegetation exhibited lower coverage of grasses and greater coverage by forbs, shrubs, and bare ground, a pattern indicative of intense grazing and soil disturbance. Acacias, absent from most mounds, were abundant in the zone bordering the mound. This pattern may reflect the favourability of mound soils, combined with the effects of high grazing pressure. Future studies of savanna vegetation should distinguish between termite mounds and Mima mounds.

Thirteen termite mounds and 13 similar-sized control plots were surveyed in central Zimbabwe in order to study large mammalian browsing and vegetation characteristics. The mounds supported almost twice as many tree species as the control plots and the woody vegetation was denser on mounds compared with the woodland plots. Species of woody plants were recorded along with the percentage of branches browsed (cumulative browsing score) by black rhino, Diceros bicornis, elephant, Loxodonta africana and other browsers combined. In addition we measured how the cumulative browsing score on three woody plant species, Acacia nilotica, Colophospermum mopane and Dichrostachys cinerea, which were common both on and off mounds, was related to the distance from mound centre. Both black rhino and elephant cumulative browsing scores were significantly higher on the mound plants compared with the woodland plots. Cumulative browsing score was negatively related to distance from the mound centre for Dichrostachys cinerea, Colophospermum mopane and Acacia nilotica. We propose that termite mound construction in miombo woodland contributes to sustaining populations of megaherbivores and perhaps some woody species in these areas.

A survey of phlebotomine sandflies was carried out in northern Nigeria to determine the distribution of Phlebotomus (Phlebotomus) duboscqi which is suspected to be the vector of cutaneous leishmaniasis in West Africa. P.(P.) duboscqi was found to be confined to the very dry areas of the Sudan savanna vegetation zone, where it utilizes termite hills as the main breeding habitats in association with rodents and lizards. Rock hyrax were located in some adjacent rocky areas. The restricted distribution range includes locations where cutaneous leishmaniasis has been recorded in Nigeria.