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Context The recent expansion of commercial agriculture in the Miombo woodlands of central Africa has led to widespread levelling of termite mounds. These mounds contain significantly lower soil organic carbon (SOC) than surrounding soils, and their levelling could largely reduce SOC content in the plough layer, which remains understudied. Objectives We aim to investigate the effects of mound levelling on SOC of the plough layer in a 1.5 km 2 plot used for commercial farming and quantify the contribution of pre-existing termite mounds to SOC variation in the levelled cropland. Methods Before and after levelling, we conducted unmanned aerial vehicle (UAV) surveys with structure-from-motion (SfM) technique, and paired soil sampling (0−25 cm) in between-mound areas. Results Termite mounds were regularly distributed but morphologically heterogeneous in the plot, with volumes ranging from 7.2 m 3 to 820.9 m 3 . Large termite mounds clustered in areas with higher topographic wetness index (TWI). Three years after levelling, SOC content in the plough layer of the plot overall reduced by 26% but variability increased by 29%. In the levelled plot, mound morphology, soil texture, and TWI explained over 40% of SOC variation, with mound morphology (characterized by hypsometrical integral, HI) being most influential. Older, larger mounds (with lower HI) were associated with lower SOC after levelling. Conclusions The immediate and significant reduction of SOC content in the plough layer due to termite mound levelling in commercial farming may affect productivity. Further research is needed to assess its long-term agricultural and ecological impacts at larger scales.

Despite the acknowledged roles of termites in tropical ecosystems, the majority of published studies of epigeal mounds still address the African fauna and are principally concerned with spatial patterns and putative inter-colony competition, rather than the links between parent soil properties and mound establishment. Further, information about the effects of habitat disturbance, and especially fragmentation, is lacking. This study assessed the abundance and distribution of the cathedral- and lenticular-type aboveground mounds of fungus-growing termites (Macrotermitinae), which are a common feature of South Indian woodlands, in relation to soil properties (vertisol vs. ferralsol) and habitat fragmentation (forest vs. highway margins). Mound abundance averaged 3.5 (standard error, SE 0.8) ha(-1) (cathedral) and 12.9 (SE 2.1) ha(-1) (lenticular), but was not influenced either by soil properties or disturbance. However, the volume of soil stored in the mounds varied between 27 (SE 8) m(3) ha(-1) (ferralsol) and 47 (SE 6) m(3) ha(-1) (vertisol). At the watershed scale, such volumes are equivalent to a 3.1-mm layer of soil if spread evenly across the landscape, roughly the same as the estimated erosion over the life of a typical mound. Significantly more nutrients were stored in lenticular mounds, especially on the vertisol, but the significance of these at the ecosystem level was considered small. In conclusion, this study suggests that termite mounds, and especially lenticular mounds, have a significant impact on soil dynamics at the watershed scale but a limited impact on the distribution of C and nutrients.

In African savannahs, mound-building termites induce higher diversity in plant communities. Biotic and abiotic filters, such as nutrients and disturbances (for example, herbivory or fire), may influence the distinct vegetation on termite mounds; however, seed dispersal has not yet been evaluated as a filter in this ecosystem. This study examined the effects of seed dispersal, particularly animal seed dispersal, on the distinct woody plant community on termite mounds in a mopane woodland in north-western Namibia. We compared the functional traits of woody plants related to dispersal, as well as responses to resource availability and disturbance, between plant communities on and those off termite mounds. We conducted vegetation surveys of woody plants in 13 paired mound–savannah plots and measured their functional traits. Soil samples were also collected from 10 of the 13 plots for soil chemical analysis to compare the differences between mound and savannah plots. Drupe-type fruits and dispersal by animals, including mammals and birds, were more dominant in plant communities on termite mounds, whereas pod and winged fruits and winddispersed species were typical in matrix communities. Termite mounds were rich in soil nutrients compared with the surrounding matrix, and soil phosphorus was associated with mound soil. We conclude that dispersal mechanisms contribute to the distinct and diverse woody plant community on termite mounds. Seed dispersal by animals is likely to be more common in the distinct woody plant community of the mounds, whereas the community in the surrounding matrix was characterised by wind dispersal.

In many tropical ecosystems, termites are important ecosystem engineers. Mound‐building termite species often contribute to topographical landscape heterogeneity, and the associated accumulation of soil moisture and nutrients affects the spatial distribution of plant communities. Plants that grow next to the termite mound are known to benefit from the provided nutrients and water storage. The other way around, protection against erosion and cooling effects on the microclimate of the mounds imposed by associated trees have been described. However, little is known regarding the influence of tree parameters and the long‐term effects on colony development. In an interval of 12 yr, we studied all Macrotermes michaelseni mounds occurring within one square kilometer of Namibian thornbush savanna in terms of morphology, life history, and associated plants, with a focus on the role of associated trees which grow directly adjacent to the termite mounds. Here, we present the results of a combined analysis of the character states recorded at the termite mound and the associated trees. More than 50% of all 345 recorded termite mounds were associated with a tree. Mounds with associated trees showed increased activity, growth, and height. Mound growth within the study period was correlated positively with the canopy coverage by the associated tree, while total mound heights were correlated non‐linear with medium canopy coverage of about 40%. Mounds with a tree covering the sun's average zenith (north) were taller, grew most within 12 yr, and were more likely to be active than those with no northern canopy coverage. Mounds associated with the evergreen Boscia albitrunca attained highest average height (195.06 ± 11.76 cm). We conclude that vital parameters like growth, size, and activity of the termite colonies are facilitated by shading associated trees. These benefits were shown to take significant effect within the span of 12 yr. This indicates a proper long‐term mutualism, not a loose alliance and not an obligative eu‐symbiosis. Therefore, we propose to use the term “partner tree” for trees associated with M. michaelseni mounds.

The extensive use of 2,4-dichlorophenoxyacetic acid (2,4-D) pesticide leads to the contamination of surfaces and groundwater. In this respect, it is critical to develop an inexpensive and environmentally friendly adsorbent for 2,4-D-laden agricultural leachate. In the current study, termite mound soil (TMS) from Ethiopia was used as an adsorbent in a batch mode aimed at the removal of 2,4-D from an aqueous solution. The TMS was characterized using Brunauer–Emmett–Teller (BET), Fourier-transform infrared (FTIR), scanning electron microscopy (SEM), atomic absorption spectrometry (AAS), and X-ray diffraction (XRD) techniques. The effects of various operating parameters such as pH, contact time, adsorbent dose, and initial concentration were investigated. In addition, the optimization process and interaction effect were studied using response surface methodology (RSM). A high 2,4-D removal percentage (89.6%) was achieved for a 2,4-D initial concentration of 50.25 mg/L at pH 2, an adsorbent dose of 15.25 g/L, and a contact time of 180.5 min. The 2,4-D adsorption isotherms could be adequately described by the Langmuir model (R2 = 0.9687), while the kinetics of the 2,4-D adsorption on the TMS best fit the pseudo-second-order model. Overall the study showed that TMS is an effective adsorbent for the removal of 2,4-D from agricultural leachate.

Our study investigated the influence of termitaria on vegetation utilization by elephants in Chewore North, Zimbabwe. Ten termite mounds and ten similar sized control plots were surveyed for soil nutrients, tree species diversity and plant biomass removal by elephants. Termite mounds had higher mean (± SE) concentrations of P, Ca, Mg and Na (0.15 ± 0.01, 48.8 ± 9.32, 5.78 ± 1.59 and 0.47 ± 0.12 meq per 100 g respectively) than control plots (0.05 ± 0.01, 3.33 ± 0.56, 1.53 ± 0.22 and 0.19 ± 0.02 meq per 100 g). However, Shannon Wiener index of tree diversity did not vary significantly between termite mounds (1.13 ± 0.280) and their control plots (0.827 ± 0.469). Contrary to most studies investigating patterns of vegetation utilization by large mammalian herbivores on termitaria, biomass removal was five times more on control plots than termite mounds. No difference in biomass removal was noted for Colophospermum mopane which had enough replicates for statistical analysis both on termite mounds and control plots. Our study negates the hypothesis that nutrient-rich soil patches will act as feeding hotspots for large mammalian herbivores. We concluded that vegetation utilization by elephants may be tree species specific, particularly in nutrient-rich environments.

Termite mounds are conventionally surmised as one of the best bio-geological indicator for groundwater occurrence in places where they inhibit. Ground magnetic survey was carried out to prove the assumption about termite mounds as an important indicator for groundwater exploration. Occurrences of 18 Termite mounds were mapped using handheld GPS to identify the suitable trend for magnetic survey. After considering all the criteria such as power lines, fences and fracture system, termite mound 2, 12 and 18 were selected in the NNE-SSW trend, and the ground magnetic survey was conducted in ESE-WNW direction which is perpendicular to the trend of the termite mounds using Proton Precession Magnetometer. Totally, 99 samples were collected with 5 m sampling interval and 50 m profile interval over an area of 22 500 sq.m. The magnetic values varied from –7 363 nT to 898 nT with the mean of –331 nT. Processed map of reduction to Equator indicates the presence of NNE-SSW and WNW-ESE magnetic breaks. Analytical signal map designated the presence of magnetic low in the WNW-ESE direction which coincides spatially with the magnetic breaks. The magnetic profile lines have also brought to light the structurally weak zones. Causative body depth range was estimated using power spectrum and Euler method which are from 120 m to 40 m and100 m, respectively. The present study appreciably brings out the spatial relationship between the termite mounds and the hydro-fractures. This confirms the assertion with regard to termite mounds as an effective tool for groundwater exploration.

The deposition of fine aeolian sediment profoundly influences the morphology of several different landscapes of the arid and semi-arid western portion of South Africa. Such landscapes and features include: (1) regularly-spaced mounds known as heuweltjies of the succulent Karoo region, (2) barren stone pavements in the more arid regions, and (3) hillslopes with smooth, curvilinear slope profiles that are mantled with coarse, stony colluvium. Investigations of each of these are presented, together with comparisons of similar features found within arid and semi-arid portions of Western North America. Recent findings suggest that the formation of the distinct, regularly-spaced heuweltjies involves a linked set of biological and physical processes. These include nutrient accumulation by termites and the production of dense vegetation patches, which, in turn, serve as a trap for aeolian sediments. Dust deposition is also responsible for the formation of stone pavements as demonstrated by research conducted principally in the Mojave Desert region of the United States. Mineralogical and geochronological studies have demonstrated that the stone clasts remain on the surface as fine aeolian sediments are translocated downward beneath the clasts resulting in a silt-rich soil horizon directly beneath the clasts. Pavements examined in South Africa have the same morphological features that can only be explained by the same process. The formation of soils on hillslopes mantled with stony colluvium are commonly viewed as having formed through the in-situ weathering of the stony colluvium. However, like pavements, mantles of coarse, stony colluvium are effective dust traps that provide the long-term stability required for advanced development of thick, fine-grained soils. This process contributes to the evolution of smooth, vegetated, curvilinear slope profiles. In each of these examples, the accumulation of dust has a profound influence, not only in soil formation, but also on the development of dominant landform characteristics. A greater awareness of these processes will contribute considerably to the growth of knowledge about soils and landscape development in the drylands of South Africa.

Phylogenetic analysis of cloned 16S rRNA gene fragments from Cornitermes cumulans (T) and its termite mound soil (TM) from the Brazilian Cerrado (Brazilian Savannah) revealed a great diversity of sequences. The bacteria detected in T and TM samples were associated with the following major lineages: Spirochaetes (T), Firmicutes (T), Synergistetes (T), Cyanobacteria (T), Fibrobacteres (T), Elusimicrobia (T), Chloroflexi (TM), Verrucomicrobia (TM), Gemmatimonadetes (TM), Armatimonas (TM), Proteobacteria (T and TM), Actinobacteria (T and TM), Bacteroidetes (T and TM), Planctomycetes (T and TM), and Acidobacteria (T and TM). All archaeal sequences only obtained from TM sample were associated with uncharacterized Crenarchaeota . The high values that were obtained for the diversity indices and evenness are indicative of high bacterial diversity from T and TM libraries, whereas the TM archaeal library exhibited low diversity. Therefore, our findings revealed differences between the bacterial communities from termite mounds and those from C . cumulans , the latter of which represents a specific bacterial composition when compared to other termite species.

The study is to develop an appropriate environmental friendly building material that would be sourced, obtained locally and used for construction of structures at a low cost by using termite mound soil, reinforced with 0%, 1%, 2%, 3%. and 4% coir fibres. Physical and mechanical tests were conducted on the different composition samples after curing. The particle size distribution showed that clay had the largest percentage with a moisture content of 3.53%, specific gravity of 2.0, liquid limit of 30.5% and plastic limit value of 25.4. The compressive strength test showed a decrease with increase in fibre content from 1% upward, modulus of rupture test showed that increase in fibre content leads to a corresponding increase in rupture while the modulus of elasticity test showed that from 3% to 4% fibre content, a decrease in the elasticity occurred. It can be concluded that low fibre inclusion into compressed termite mound brick is feasible if fibre content do not exceed 2% and thus can be used for both load and non-loading bearing structures.