Variability in soil chemistry and arbuscular mycorrhizal fungi in harvester ant nests: the influence of topography, grazing and region

Harvester ants are important disturbance agents across western North America, but the effects of ant disturbances on soils may vary considerably with topography and land use. We examined how soil properties and arbuscular mycorrhizal (AM) fungi in harvester ant nests varied across spatial scales according to topography, grazing regime and region. Soils from undisturbed areas were compared with nest disturbances created by two species of harvester ants, Pogonomyrmex occidentalis on shortgrass steppe in Colorado and P. rugosus on Chihuahuan desert grassland in New Mexico, in 1996 and 1997. Nests of both ant species were enriched with NO₃^--N, total P and roots colonized by AM fungi. Soil moisture was higher in P. rugosus' nests and lower in P. occidentalis' nests compared to surrounding areas. Soil pH was consistently lower in ant nests. Broad-scale factors such as grazing, topography and site affected most soil properties in and away from ant nests. Site exerted a strong influence on soil organic matter, pH and moisture. Within sites, topography had a significant affect on pH. Mycorrhizal colonization was influenced by site and topography in 1996 only, a substantially wetter year at both sites. Lastly, nutrient levels were largely determined by the fine-scale effects of ant disturbances. Principal components analysis revealed that, after removing site-level effects, harvester ants have similar functional roles in creating soil heterogeneity in these two different semiarid ecosystems.     

Nest-mounds of the yellow meadow ant (Lasius flavus) at the “Alter Gleisberg”, Central Germany: Hot or cold spots in nutrient cycling?

Nests of the yellow meadow ant (Lasius flavus) occur at high densities in grasslands worldwide. Although many studies have shown that L. flavus nests influence soil nutrient contents, little is known about their effect on soil nutrient cycling rates. The aim of this study was to examine the role of nest-mounds inhabited by L. flavus as potential ‘hot spots’ for soil nutrient cycling. Six pairs of nest-mounds and control soils were selected at a grassland site at the plateau of the Alter Gleisberg (Thuringia, Central Germany). L. flavus significantly modified the soil environment within the nest. In comparison to the control soils, nest-mounds were characterized by slightly higher soil temperatures during the summer months. In addition, we found that nests were related to decreased potential C mineralization rates and increased potential net N mineralization rates. Nest-mound soil exhibited lower amounts of SOC, hot-water extractable DOC and DN, and higher concentrations of leachable DOC and DN. Moreover, ants promoted the enrichment of base cations in the nest. Differences in the soil environment between nests and control soils were possibly a result of the burrowing activity of ants, soil mixing, accumulation of aphid honeydew, and decreased plant-derived nutrient inputs into the nest-mound soil. In conclusion, L. flavus nest-mounds had a significant but element dependent effect on the soil nutrient cycling and may represent cold spots for C cycling and hot spots for N cycling. Thus, L. flavus nests increase the spatial heterogeneity of soil properties and create unique micro-sites within grassland ecosystems.     

Development of harvester ant colonies alters soil chemistry

Nests of the harvester ant Pogonomyrmex barbatus typically contain higher concentrations of organic matter, nitrogen and phosphorus than surrounding soils. The difference between nest soils and surrounding soils is due, at least in part, to ant foraging behavior. Ants retrieve seeds from the environment and concentrate seed nutrients in the vicinity of the nest. But elevated nutrient concentrations in nests may also reflect initial conditions, if nest-founding queens are more likely to choose or survive in soils with high organic matter and nutrient content. By measuring the soil nutrient content and surface area of P. barbatus nests ranging from 1 to 20 years of age over two sampling periods, we (a) investigated the relationship between nest soil characteristics and colony age, and (b) tested the hypothesis that nest soils differ from background soils when nests are established. Nest surface area increased with colony age until age 5-10 years and leveled off thereafter. Relative to surrounding soils, concentrations of total nitrogen and orthophosphate increased, and pH decreased, with increasing colony age. The difference between nest soils and surrounding soils in total nitrogen, nitrate, and ammonium concentrations also increased over a 9-month interval between sampling bouts. Extrapolations from regressions of soil chemical variables against colony age provided no evidence that nest founding and early colony survival is more likely to occur in high-nutrient soils.     

Phosphorus fractionation in lowland tropical rainforest soils in central Panama

Phosphorus availability is commonly assumed to limit productivity in lowland tropical rainforests, yet there is relatively little information on the chemical forms of soil phosphorus in such ecosystems. We used the Hedley sequential fractionation scheme to assess phosphorus chemistry in five soils supporting tropical rainforest on Barro Colorado Island, Republic of Panama. The soils represented a range of orders (Inceptisols, Alfisols, and Oxisols) formed on contrasting geological substrates and topography, but under uniform climate and vegetation. Total phosphorus in surface horizons ranged between 315 and 1114 mg P kg^− 1, being lowest on a soil derived from marine sediments and highest on soils derived from andesite. The majority of the phosphorus occurred in recalcitrant forms, although between 14% and 39% occurred as organic phosphorus. Readily-available phosphate, as extracted by anion-exchange membranes, occurred in small concentrations (4–13 mg P kg^− 1), although labile phosphorus, defined as phosphate extracted by anion-exchange membrane plus inorganic and organic phosphorus extracted by 0.5 M NaHCO₃, accounted for between 4.7% and 11.4% of the total soil phosphorus. Our results indicate a strong control of geology and topography on soil phosphorus in tropical rainforests, which may have important implications for understanding the diversity and distribution of plant species in such ecosystems. Further, some of the most common soils on Barro Colorado Island, including those on the 50 ha forest dynamics plot, are rich in phosphorus despite their relatively advanced stage of pedogenesis.     

Increased CO2 emission and organic matter decomposition by leaf-cutting ant nests in a coastal environment

Leaf-cutting ants perform a vital role in the cycling of carbon and nutrients in tropical ecosystems. Nests have high levels of organic matter and refuse dumps host up to two times more soil micro-organisms than non-nest soil. The increased levels of organic matter in the soil of nests, however, can affect CO₂ emissions from soil and alter the balance of atmospheric CO₂. We aimed at assessing the effect of nests of the leaf-cutting ant Acromyrmex balzani on CO₂ emissions in a coastal area of Northeast Brazil. Results show that A. balzani nests emitted up to four times more CO₂ than the surrounding soil and emissions were positively correlated with soil moisture and soil organic matter (SOM) content. In addition, field experiments demonstrated that refuse material has a lower residence time than the leaf material brought to the colonies. Despite the high density of nests and high content of SOM compared to adjacent control soil, CO₂ emissions by A. balzani nests represent only 0.3% of the total CO₂ efflux by the studied ecosystem. Although these effluxes account for a relative small portion of the total soil CO₂ emission, they are still important for the understanding of C balance, especially when one considers the thousands of tons of CO₂ emitted each day, across entire Neotropical regions where leaf-cutting ants occur.     

Unique soil microbial assemblages associated with grassland ant species with different nesting and foraging strategies

Ants are important ecosystem engineers and can be abundant in extensively managed grassland ecosystems. Different ant species create nests varying in structure and size, and tend to have a variety of feeding strategies. Differences in food imported to the nest and contrasting nesting behaviour may control soil microbial community structure in nest soil, with cascading effects on nutrient cycling, but this has not been tested in grassland ants. Soil and ants were sampled from nests of three ant species: two formicines; Lasius flavus (aphid farmer/scavenger, mound builder) and Formica lemani (scavenger/hunter, non-mound builder), and a myrmicine; Myrmica sabuleti (hunter/scavenger, non-mound builder), in an extensively grazed temperate grassland and compared to similar soils without ants. Microbial assemblages were determined using molecular approaches (terminal restriction length polymorphism and automated ribosomal intergenic spacer analysis). Both aboveground (vegetation diversity) and belowground (soil physico-chemical properties) components were measured to assess the potential of the different ant species to modify the environment. Stable isotope ratios (δ¹³C and δ¹⁵N) of ant tissues and nest soil organic matter confirmed differences in trophic distances. Significant changes in soil pH, moisture content, total C and total N, and in vegetation composition, demonstrated ant ecosystem engineering effects. In turn, nests of L. flavus, M. sabuleti and F. lemani had different microbial activities and harboured significantly different microbial assemblages (total bacteria, total fungi, ammonia-oxidising bacteria and nitrogen-fixing bacteria), but the diversity was similar. These findings suggest that grassland ants can control microbial assemblages via changes in physical and biological soil characteristics in their nests, and as such, different ant species harbour unique microbial assemblages in nests.     

Wood ant nests as potential hot spots for carbon and nitrogen mineralisation

Red wood ants (the Formica rufa group) build large nests which can last for many years. The ants often bring large quantities of conifer litter to their mounds. In this study we compared chemical properties of the forest floor and ant-nest materials of red wood ants at two different sites in Sweden. We also did an incubation study in the laboratory to determine C and N mineralisation rates of soil and nest materials at two moisture levels. Some chemical properties, e.g. pH and C/N ratio, differed between sites. Nests were always drier, had a higher C/N ratio and often had higher NH₄⁺ concentrations than the surrounding forest floor. This indicates that the nests increase spatial heterogeneity of the forest floor not only because they contain large amounts of organic matter but also because of qualitative differences in nest composition. In the incubation study, experimentally increased moisture levels in the nest material resulted in net N immobilisation, while surrounding litter and humus materials showed net N mineralisation. The CO₂ evolution was clearly increased by increased moisture. Dry conditions in the nest material prevented it from being decomposed and, since there were no plants to take up N, inorganic N accumulated. However, based on our results we hypothesise that ant nests do not produce large amounts of inorganic N as long as the ants bring fresh litter with high C/N ratio to the nests and keep the nests dry. However, the nests can be considered as potential "compost heaps" which probably decompose faster and will be a source of N leaching when the ants no longer maintain the specific dry conditions.     

Variability in soils and vegetation associated with harvester ant (Pogonomyrmex rugosus) nests on a Chihuahuan Desert watershed

The effects of harvester ant (Pogonomyrmex rugosus) nests on the density and cover of spring annual plants and on soil characteristics were measured at three locations characterized by different soils and dominant vegetation on a desert watershed. There were few differences in vegetation and soils associated with harvester ant nests at locations at the base of the watershed where brief periods of flooding and sediment deposition occur at periodic intervals. At mid-slope locations, there were significant increases in total nitrogen, inorganic phosphorus, and cover (biomass) of four species of spring annuals at the edges of nest disks when compared with reference sites. The spring annuals that exhibited increased cover were species that increase biomass as a function of available nitrogen. At a clay-loam, Scleropogon-Hilaria, grassland site, there were significant reductions in the concentrations of Ca²⁺ and Mg²⁺, significant increases in nitrate and total nitrogen, but a significant increase in cover in only one species of annual plant. The data demonstrate that the effects of ants on soil properties and vegetation vary with site location and soil type.     

Ant-induced soil modification and its effect on plant below-ground biomass

Lasius flavus is a dominant mound-building ant species of temperate grasslands that significantly modifies soil parameters. These modifications are usually the result of workers’ activities such as food accumulation and nest construction. An alternative hypothesis that could explain changes in soil is colony founding in areas of higher soil fertility.In our study we investigated several soil parameters sampled in 10 ant nests and adjacent (control) plots in mountain grassland in Slovakia. The alternative hypothesis was tested by comparing occupied and abandoned mounds. While we found increased concentrations of available P and K in the nests, concentrations of total C, total N, Ca²⁺ and Mg²⁺ were lower there. We propose that differences found between the soil of nests and control plots are entirely a product of ant activity during mound occupancy and not due to initial soil differences during nest establishment. This was confirmed by the comparison of occupied and abandoned nests in which the soil fertility of abandoned nests was similar to conditions in the surrounding soil.Along with the modification of soil chemistry, we recorded changes in soil physical properties and the vertical distribution of nutrients. Ant nests were characterized by the dominance of 0.02–0.1 mm particles and lower bulk density. In the same habitat, nutrient concentrations did not change along the vertical gradient in contrast to control plots where soil nutrients decreased and bulk density increased with depth. Root biomass followed the vertical pattern observed with nutrients: in control plots, most roots were concentrated in the uppermost layer (0–3 cm), whereas they were evenly distributed along the vertical gradient in the nests. We also found that rhizome internodes of Agrostis capillaris were thinner and longer in plants from the mounds. Changes in soil physical properties, vertical distribution of nutrients and root biomass in the nests are most probably a consequence of mounding and soil mixing (bioturbation), which has been less reported on in ant-soil studies.     

Phosphorus forms as affected by abandoned anthills (Formica polyctena Förster) in forest soils: sequential extraction and liquid-state 31P-NMR spectroscopy

Ants are known to concentrate phosphorus (P) inside their nests via collection of food and litter. To elucidate the possible effects on long-term availability of soil P, five anthills abandoned by Red wood ant (Formica polyctena Förster) > 5—20 years ago were characterized for soil P forms in a temperate Danish deciduous forest. Sequentially extracted P fractions and liquid-state ³¹P nuclear magnetic resonance (NMR) spectra were obtained on surface samples (0—10 cm) from abandoned anthills and adjacent topsoil; in addition one representative soil profile in an abandoned anthill was investigated. The results show that different inorganic and all organic P fractions were enriched by a factor of 2.0—3.3 inside anthills relative to the surrounding soil. The soil underneath the abandoned anthill had higher P contents until 50-cm depth. Phosphorus composition was less affected by former anthill construction. Only the younger anthills revealed a preferential accumulation of labile organic P forms such as Na-HCO₃ extractable P or diester P. The accumulation of the stable and moderate labile P forms, however, persisted for ≥ 20 years after abandonment. We concluded that former ant activity enhanced long-term P availability of soil due to high local P inputs, whereas changes of the P form distribution lasted 5—10 years after nest abandonment.     

Effects of harvester ant (<Emphasis Type="Italic">Messor</Emphasis> spp.) activity on soil properties and microbial communities in a Negev Desert ecosystem

Harvester ants (Messor spp.) function as an essential link between aboveground resources and below-ground biota such as the microbial community. We examined changes in soil microbial biomass and functional diversity resulting from harvester ant (Messor spp.) activity in the Negev Desert, Israel. Abiotic and biotic soil parameters were recorded during two seasons—wet and dry—also representing food availability periods for the ants (low and high seed availability, respectively). Soil samples were collected monthly from the 0- to 10- and 10- to 20-cm soil layers: (1) near the nest entrance, (2) under chaff piles, and (3) at a 2-m radius from the nest entrance (control). Harvester ant activity increased the percentage of organic matter, total soluble nitrogen, and microbial activity in nest-modified soils in comparison to the control soils. Higher CO₂ evolution was recorded in the low-seed season in ant nest soils than in the control soils. During the high-seed season, higher carbon dioxide evolution was recorded only at the nest entrance locations. There were no differences in microbial biomass between the low- and high-seed seasons, but highest microbial biomass was found under chaff in low-seed season and in nest soils in high-seed season. Microbial functional diversity was higher in nest-modified soils than in the control soils. This study suggests that the effect of harvester ant nests on soil fertility is due to increased microbial biomass and microbial activity in ant nest-modified soils.     

Rainfall/runoff/erosion relationships and soil properties survey in abandoned shallow soils of NE Spain

Purpose

Shallow soils previously cultivated under terraced systems may change their properties after agricultural release and spontaneous plant colonization. Investigations were conducted in terraced fields (NE Spain) to prove that vegetation installed after the abandonment may generally improve soil properties by the formation of stable organic horizons. However, restriction in plant species along the natural vegetation succession and intensification of erosion processes may occur after abandonment depending on fire frequency and soil use history.

Materials and methods

Ten environments with different plant covers under a Lithic Xerorthent were selected and erosion plots (Gerlach type) installed providing their best adaptability at the terrace scale. Selected soil environments represented the sequence of abandonment: from current poorly cultivated soils, soils under pasture, soils under shrubs, and soils under stands of pine and cork trees. Relevant rainfall events producing runoff and erosion were recorded from November 2011 to May 2012. Erosion rates and erosion components were analysed in sediments and water in order to monitor carbon, nitrogen and other nutrient removal by overland flow. Similarly, the physical and chemical properties of the soil environments under study were determined at the same time interval of runoff erosion.

Results and discussion

Soils under pasture, vines and recently burnt pine forest produced the highest runoff followed by soils under shrubs and forest. However, eroded soil yields and nutrient removal were much higher in cultivated soils and soils in recently burnt sites, which had shown poorer soil properties with respect to soils abandoned for longer and preserved by fire. Fire-affected soil environments also showed a thinner organic horizon and reduced water retention. Although erosion rates and nutrient depletion were low in all environments with respect to other areas of Spain, higher splash than water erosion was an early warning indicator of the high susceptibility to degradation of these shallow soils.

Conclusions

Results outlined that the renaturalization dynamics after agricultural abandonment are complex biophysical processes involving the parent material, depth to bedrock and other soil properties as well as the succession of vegetative cover and plant associations responsible for building a new soil mantle contrasting with erosion processes. Planning for management of land abandonment is strongly recommended.

     

Respiration in wood ant (Formica aquilonia) nests as affected by altitudinal and seasonal changes in temperature

Wood ants build large, long-lasting nests and maintain stable high temperatures in nest centers from April to September to support brood development. Similar nest temperatures have been recorded regardless of latitude and altitude, suggesting that nests from colder environments produce more heat than nests from warmer environments. We measured changes in temperature and in situ respiration in nests from 700 and 1000 m a.s.l. We also sampled ants and nest materials from the same nests and measured their respiration at 10 and 20 °C in the laboratory. Both ant and microbial respiration increased greatly as temperature increased in spring, especially at 1000 m, resulting in the increase in nest temperature in spring. Metabolic activity greatly increased for ants in March and for nest microorganisms in April when nutrient contents also increased because of input of plant material and food. Nests from 1000 m maintained similar temperatures as nests from 700 m in summer but were colder in winter. Ants were responsible for the maintenance of high temperatures during summer but metabolic activity did not differ between the two altitudes, suggesting that the increased respiration and heat production in summer by ants at the higher altitude resulted from an increase in numbers of ants per colony.     

埃塞俄比亚罗毕高原含铬雏形土地区凋落物饲喂的白蚁(Macrotermes spp)的化学性质及其生化活动的研究

Termite(Macrotermes spp.) mounds are complex biological habitats originated by the termite activity and possessing peculiar physical, chemical and biochemical properties. In this study we examined the concentration of nutrients and the biochemical activity of abandoned soil and mounds colonized by termites of the genera Macrotermes located in the Borana District, Ethiopia. To elucidate the magnitude and persistence of the termite-induced effects, we also studied an abandoned mound, previously colonized by termites of the same genera formed on the same soil. Results confirmed that termite-colonized mounds are ‘hot spots' of nutrient concentration and microbial activity in tropical soils. This is due to the termite driven litter input and decomposition. The abandoned mounds showed higher microbial biomass and activity and displayed a nutrient redistribution and a greater microbial activity than the adjacent soils. These findings allowed us to hypothesize a model of nutrient cycling in colonized soils and a partition of the relative roles of termites and soil microorganisms in nutrient location and turnover in tropical soils. These results may be also useful for the optimal management of termite-colonized soils.     

Impact of a soil feeding termite,<Emphasis Type="Italic"> Cubitermes niokoloensis</Emphasis>, on the symbiotic microflora associated with a fallow leguminous plant<Emphasis Type="Italic"> Crotalaria ochroleuca</Emphasis>

The influence of a soil-feeding termite nest (Cubitermes nikoloensis) on the development of a symbiotic microflora (rhizobia, arbuscular mycorrhizas) was tested in a pot experiment with a tropical legume (Crotalaria ochroleuca). Our results confirmed the role of soil-feeding termite nests as sites of high nutrient concentration, as a significantly higher content of available P and mineral-N was found in the mound wall. Arbuscular mycorrhizal spores increased in the soil near the termite mound. The mound soil itself almost totally depressed mycorrhizal establishment. The positive effect of the soils close to the mound was also evidenced by the number of nodules per root system as well as the nodule biomass per legume plant grown on this medium. Better growth of Crotalaria seedlings was observed in the soils from the mound wall; the shoot biomass increased by a factor of 9 and the root biomass by a factor of 6 as compared to the control soil (10 m away from the mound). Plant growth on soils from the immediate vicinity of the mound showed intermediate results but a higher N content per biomass unit. This probably reflected the association with arbuscular mycorrhiza and rhizobia. This work evidenced the linkage of plant nutrition to nutrient availability in mound material and the indirect mediating effect of the symbiotic microflora.     

Leaf-cutting ant (Atta Sexdens) and nutrient cycling: deep soil inorganic nitrogen stocks, mineralization, and nitrification in Eastern Amazonia

Nest excavation and agricultural activities of the leaf-cutting ant Atta sexdens create complex belowground heterogeneity in secondary forests of Eastern Amazonia. We examined the effects of this heterogeneity on inorganic-N stocks, net mineralization, and net nitrification to test the hypothesis that the bulk soil of the nests has higher net rates of mineralization and nitrification than soil that was not affected by the influences of ant nests, throughout the profile. This study was conducted in a secondary forest at Fazenda Vitoria, near Paragominas in the Eastern Brazilian Amazon, where a previous study showed that the bulk soil of ant nests had elevated NO₃⁻. The results of the inorganic-N measurements were consistent with the previous study, showing elevated NO₃⁻ deep in the soil profile of the nests. However, neither net mineralization nor net nitrification were significantly greater at depth in the mineral soil of the nests compared to soil that was not influenced by nests (P=0.05), although variability was higher in the nest soil. These results suggest that the NO₃⁻ may have diffused into the surrounding mineral from the N-rich organic matter buried by the ants in chambers within the deep soil.     

Carbon,nitrogen and phosphorus dynamics of ant mounds (Formica rufa group) in managed boreal forests of different successional stages

Wood ants (Formica rufa group) are ubiquitous in European boreal forests and their large long-lived mound nests, which mainly consist of forest litter and resin, accumulate carbon (C) and nutrients. The C and nutrient dynamics of wood ant mounds in response to forest succession have received minor attention in boreal forests. We aimed to study whether the C, nitrogen (N) and phosphorus (P) concentrations and the bulk density of ant mounds differ from those of the surrounding forest soil, to estimate the C, N and P pools in ant mounds, and to test whether the concentrations and pools change with forest age. Norway spruce (Picea abies (L.) Karst.) stands on medium-fertile sites in 5-, 30-, 60- and 100-year stand age classes were studied in eastern Finland. Carbon and P concentrations in the above-ground mound material were higher than those in the surrounding organic layer. The C, N and extractable P concentrations were higher in the soil under the ant mounds than in the surrounding mineral soil (0–21 cm). The low bulk densities in the ant mounds and the soil below them could be a result of the porous structure of ant mounds and the soil-mixing activities of the ants. The C/N ratios were higher in the mounds than in the organic layer. Carbon concentrations in the ant mounds increased slightly with stand age. Carbon, N and P pools in the ant mounds increased considerably with stand age. Carbon, N and P pools in ant mounds were <1% of those in the surrounding forest soil. Nevertheless, the above- and belowground parts of the ant mounds contained more C, N and P per sampled area than the surrounding forest soil. Wood ants therefore increase the spatial heterogeneity in C and nutrient distribution at the ecosystem level.     

Physical, chemical and phosphatase activities characteristics in soil-feeding termite nests and tropical rainforest soils

Little is known about the relationship between soil biological function and the physical and chemical characteristics of soil-feeding termite nests in the Lopé tropical rainforest (Gabon). We compared nine soil-feeding termite nests of Cubitermes of different ages (fresh to mature to old) and six surrounding soils that originated from three forests differing with respect to age and vegetative cover according to 14 physical and chemical variables and acid (pH 4) and alkaline (pH 9) phosphatase activities. Physical and chemical variables of the studied samples were influenced by the three factors tested: (1) forest age, (2) termite activity (nest versus soil), (3) termite nest age. Soils from the gallery forest were strongly discriminated from all the other soils studied notably due to their high organic matter contents. All mature nests showed significant increases in K, P, clay and fine silt, pH, and cationic exchange capacity compared to soils. Some nests also had increased amounts of organic matter and larger water retention capacities. Moreover, we observed that with age the termite nests possessed decreased values of these variables from fresh to mature to old. Likewise, phosphatase activities also differed according to the three factors tested. Due to its high organic matter contents, the highest phosphatase activities were noted in the gallery forest. Within each forest, phosphatase activities decreased in mature nests compared to soils and tended to be higher in fresh nests compared to mature nests. These differences might be due to an inhibition by high inorganic P contents, as mature nests were enriched in this element and to the quality of organic matter as nests are built with termite faeces. Termite activity has an important role in influencing physical and chemical variables and phosphatase activities.     

EVALUATION OF DIFFERENT ANT NEST MEDIA FOR GROWTH AND YIELD OF SOYBEAN

The nutrient constituent of nest structures in relation to the growth and yield of soybean (Glycine max L. Merrill) were studied. Nest structures collected from mango, Mangifera indica; bush mango, Irvingia gabonensis; kola, Cola nitida; newbouldia, Newbouldia laevis, oil bean plants, Pentaclethra macrophylla, ground termitaria and unaffected soils were used. Except in a few instances, plant height, stem girth, pod and grain yield of arboreal ant-nest media plants were significantly (P < 0.05) greater, compared with those of ground termite nests; as nest structures’ media were to their corresponding adjacent unmodified soils. Termitaria and P. macrophylla host media delayed maturity compared to those of the other nest structures or the unaffected soils. Nutrient properties were positively correlated with growth and yield parameters, but correlated negatively with maturity date. Principal component analysis revealed phosphorus in nest structures as being critical for optimum soybean yield. These nutrient rich structures could therefore be harnessed to ameliorate the iron-and/or aluminum-induced phosphorus-deficient problems of acidic tropical soils to boost soybean production in this area.