In this study, we compared the richness of ground-dwelling ants among three different sugarcane management systems (with the application of the insecticide fipronil and the addition of vinasse; with fipronil and no vinasse; and with vinasse and no fipronil, i.e., an organic production system) to evaluate whether the feeding/foraging types vary according to the management system. We tested the hypothesis that organic management increases species diversity because there is no use of chemical inputs. Estimated species richness was significantly higher in the organic management system than in the systems that used fipronil with vinasse. Generalists species were prevalent in all sugarcane fields, regardless of the production system, whereas predatory and fungivorous species were infrequent. However, the organically managed field had many predatory species. Our results suggest that fipronil with vinasse in sugarcane cultivation alters the ant community, possibly disrupting the functions performed by the edaphic fauna, such as control of arthropod crop pests, due to reduced predator species richness.

A comprehensive assessment of the effect of disturbances on tropical and subtropical forests is needed to better understand their impacts on forest structure and diversity. Although taxonomic and functional diversity measures have been successfully adopted in this context, phylogenetic diversity metrics are still poorly explored. We compared the phylogenetic structure of the seed rain and regenerating seedling community in patches of an old-growth Atlantic Forest remnant dominated or not by a ruderal bamboo species, Guadua tagoara. We sampled those patches before and after illegal harvesting of the palm Euterpe edulis thus assessing if the harvesting led to changes in the phylogenetic structure of the seed rain and the regenerating community in both patches. Bamboo-dominated patches showed a significantly higher presence of species in the seed rain that were more distantly related to each other in the phylogeny than expected by chance compared with patches without bamboos, but this difference disappeared after palm-heart harvesting. Contrary to what we expected, we did not find significant changes in the phylogenetic structure of seedlings before or after palm-heart harvesting. The phylogenetic structure at the tips of the phylogeny was random overall. The maintenance of a higher presence of far relatives in the phylogeny of the seedling community suggests, assuming trait conservatism, that despite bamboo dominance and palm-heart harvesting, functional diversity is being preserved at least in the early regenerating stages and in the time frame of the study. However, higher presence of pioneer taxa after palm-heart harvest indicates that this disturbance may lead old-growth areas to earlier successional stages.

The Janzen–Connell hypothesis suggests that highly specific pathogens decrease seedling survival close to the parent plant; however, the underlying mechanism remains unclear. Here, we tested the host specificity of soil pathogens to germinating seeds of Cyclobalanopsis fleuryi and Cryptocarya chinensis in tropical montane rain forest and cloud forest on Hainan, south China. Rhizospheric soils surrounding eight adult trees per species were collected in each forest type and divided into five soil treatments: parent, fungicide-sterilized, autoclave-sterilized, Fusarium-added and Pythium-added soils. Surface-sterilized seeds were sown in each of the five soil treatments and grown in two forest types. The seed germination percentages were significantly higher in sterilized soils (C. fleuryi, 41.5%; C. chinensis, 29.4%) than in non-sterilized soils (C. fleuryi, 28.3%; C. chinensis, 17.1%) in montane rain forest. The seed germination percentages in rhizospheric soil of conspecific parent trees were significantly lower in montane rain forest (C. fleuryi, 17.3%; C. chinensis, 10.5%) than in cloud forest (C. fleuryi, 37.1%; C. chinensis, 21.1%). Our results also suggest that the level of pathogen activity in each tree species varies depending on the environment. Our results support the hypothesis that host-specific pathogens shape tree species composition by differentially affecting seed germination under different environmental conditions.

Forest fires pose an important threat to tropical rain-forest biodiversity. In the present study, we assessed ground layer (herb and shrub) communities in six differentially disturbed landscape plots in East Kalimantan, Indonesia, including primary and logged forest and once-, twice- and frequently-burnt forest. Overall, we recorded 175 species of herbs and shrubs; richness was highest in twice-burnt forest and lowest in logged forest. Vegetation and topographical variables including the percentage of the plot burnt and tree abundance were significant predictors of variation in composition. The main compositional gradient showed a clear distinction between subplots in unburnt versus burnt forest. A subset of subplots in burnt forest, however, clustered together with subplots from unburnt forest. These plots were located in a network of relatively unscathed forest along floodplains that persisted in the burnt-forest matrix. Small plant species associated with unburnt forest included several species of Dryopteridaceae, Marantaceae and Rubiaceae. Species associated with once- and twice-burnt forest included Mikania scandens (Compositae), Microlepia speluncae (Dennstaedtiaceae), Nephrolepis cf. biserrata (Nephrolepidaceae), Lygodium microphyllum (Schizaeaceae) and Hornstedtia cf. reticulata (Zingiberaceae). The frequently-burnt landscape plot was characterized by a high cover of the grass species Imperata cylindrica and the invasive exotic shrub Chromolaena odorata. Importantly, these species and other exotics had also invaded the once- and twice-burnt forest and represent a potential threat to forest recovery.

Itaipu Hydroelectric Power Plant initiated a large reforestation programme after the expropriation of the areas destined for the formation of the reservoir. This study aimed to evaluate the effectiveness of forest restoration of the Seasonal Semideciduous Forest in the Upper Paraná Atlantic Forest ecoregion, Brazil, using epigaeic ant assemblages as bioindicators, by comparing ant species richness and composition in the Reservoir Protection Strip with adjacent areas, such as the primary forest of the Iguaçu National Park and the Permanent Preservation Area located on a rural property and agricultural areas. In total, 171 ant species were identified. Ant species richness was higher in forest than in agricultural areas and did not differ among forest areas. However, ant species composition in forest areas, regardless of the restoration technique used, was not similar to the primary forest, possibly due to variation in forest recovery time. This study highlights the great value of the Iguaçu National Park as a conservation unit. Also, it reveals that the efforts for the creation and maintenance of the Reservoir Protection Strip, which remains without anthropic interventions for years, might indeed lead to a complete recovery of the ant species composition over time, reinforcing their great importance for biodiversity conservation.

Termite mounds have been poorly studied in tropical rainforest in contrast to those of savannahs where they create fertility hotspots and influence the spatial pattern of vegetation. An inventory of termite mounds and of 15 tree species with a diameter at breast height ≥ 10 cm was carried out in two 800-ha blocks, in two rainforest sites located in northern Congo. We used inhomogeneous and intertype K functions to study the spatial pattern of termite mounds and of tree species around mounds, respectively. We found that mounds in Loundoungou were over-dispersed within a radius of less than 70 m, while those in Mokabi were randomly spaced. Tree species within a 20-m radius around a mound were aggregated towards the mound, e.g. Entandrophragma cylindricum, randomly distributed, or even repulsed by the mound. The specific responses also differed in the two sites. These results suggest that (i) the mounds in Loundoungou were created by savannah termite species 3,000-2,000 years BP during the Late Holocene Rainforest Crisis and (ii) the mounds in Mokabi are characteristic of forest mounds. The impact of termite mounds on the spatial pattern of tree species is thus site-dependent, and these differences might be due to species seed dispersal strategies and to soil calcium concentrations.

Borneo is the centre of diversity of the palm genus Pinanga. At least 13 understory species have been recorded in the Ulu Temburong National Park in Brunei, but little is known of their persistence. Changes in populations of Pinanga understory palms may be indicative of more widespread changes due to climate change, such as changes in rainfall, which may be important for the palm diversity in the protected area. However, we know little about the population dynamics of these palms, how persistent their populations are or if they behave similarly over long time frames. In 1998, populations of five co-occurring species of Pinanga at several locations in the Ulu Temburong National Park were documented. This project aimed to undertake a comprehensive resurvey of the original five Pinanga palm species populations in order to assess if they showed similar population changes across sites and species after two decades. Overall, most species maintained their population size in the surveyed region but not consistently among sites, and one species significantly declined in abundance. There was considerable variation in population growth rate (R) within and among species and sites that was significantly correlated with density and the percentage of multi-stemmed plants. There was evidence of pulsed recruitment in some species and or sites rather than steady or exponential patterns of population growth.

Reproductive success of many plant species declines in fragmented habitat, but this effect is little studied in trees of tropical rain forest understorey. Paypayrola blanchetiana (Violaceae) is a continuous-flowering treelet endemic to the Atlantic rain forest of north-east Brazil. Plants are distributed in localized patches. Flower, fruit and seed production of a total of 86 trees was quantified in six forest fragments, each belonging to one of two categories of size (> 300 ha vs. < 50 ha) and fragmentation history (isolated for c. 25–30 y vs. at least c. 50 y). Relative fruit set (fruits/flower) and seed set (seeds/ovule) were calculated for a spatial (total fruit set of tree individuals) and a temporal analysis (combined month-by-month fruit set in patches in response to different flowering intensities). Fruit set (1%) and seed set (0.6%) were very low, but variable among trees. Plants in large fragments had significantly higher fruit set and seed set than plants in small fragments. Trees in older fragments, however, displayed similar fruit and seed set to those in recently created ones. We found no interaction effect on seed set of fragment size and isolation time. Seed set was a negative function of patch flower density. Possible drivers of the observed patterns are discussed.

The bushy-tailed opossum (Glironia venusta) is a small arboreal marsupial found in the Amazon basin. G. venusta is rarely seen and has few published sightings throughout its range. Videos (N = 79) were obtained from arboreal camera traps located in the Las Piedras Amazon Center near the Las Piedras River (SE Peru) from April 2017 until November 2017. Our new records, the first for the Las Piedras River, demonstrate that the species is nocturnal with activity peaks at 3:00 h and 20:00 h in the hours of complete darkness. The abundance of camera trap footage of such a rarely observed species further demonstrates the effectiveness of arboreal camera trapping to conduct species assessments.

Oceanic islands, due to their evolutionary history and isolation, play a dual role of having high endemicity and being vulnerable to extinctions, with most known extinctions occurring on islands. Plant–animal interactions are particularly important on islands, as island systems generally have low redundancy and are more vulnerable to disruption either via extinction or by invasive species. Here, we examined the fruit removal and seed predation of a keystone palm, Caryota mitis, on Narcondam, a remote oceanic island. The island endemic Narcondam Hornbill (Rhyticeros narcondami) was the sole seed disperser of the palm (90 hours; N = 15 trees), with mean (± SE) visitation rate being 0.23 (± 0.06) individuals per hour and fruit removal rates of 3.5 (± 1.5; range: 0–16) fruits per visit, indicating a lack of redundancy in seed dispersal of the palm on this island. Whereas the invasive rodent, Rattus cf. tiomanicus, was the sole predator of palm seeds (N = 15 individual fruiting palms, 416 trap nights). Overall, 17.1% of the seeds placed (N = 375 seeds) were removed. Seeds placed under and away from the canopy, and at different densities (2 plots with 10 seeds each; 1 plot with 5 seeds, respectively), showed similar removal rates. This indicates density-independent seed predation and the lack of safe regeneration sites for Caryota mitis, with potential deleterious effects on subsequent stages of the ‘seed dispersal cycle’. Here, from a data-deficient site, we provide baseline information on the plant–frugivore interaction of a keystone palm and the potential impacts of an invasive rodent.

In the vast Neotropic seasonal environment, the most diverse family of bats, the Phyllostomidae (leaf-nosed bats), includes up to 93 species. As the quality and quantity of food resources fluctuate in the habitats, diet heterogeneity is observed among bat species and regions of the Neotropics. In this study, we investigated by faecal analyses, how the dietary niche (DN) of eight Phyllostomidae bat species (Artibeus planirostris, A. fimbriatus, Carollia brevicauda, C. perspicillata, Chiroderma villosum, Glossophaga soricina, Platyrrhinus lineatus, and Sturnira lilium) that occur in a karstic area in the Midwest region of Minas Gerais, Brazil, change in response to seasonal food availability. We recorded the consumption of insects and nine plant families. Moraceae was the most frequent, followed by Piperaceae. Given that seasonal dietary changes can be subtle and hardly noticeable along with fluctuating habitat conditions, we performed the DN decomposition of the eight bats species into subniches, by analysing the data with the WitOMI, which is a decomposition of the niche into temporal subniches. By improving the accuracy and details of the results, we assessed the effects of abiotic (precipitation and environmental temperature) and biotic (quantity and quality of food resources) interactions within the phyllostomid bat community. For each species, we compared niche breadth and overlap and found higher values for the dry season among morphologically similar species. The results of our study suggest that ecologically similar bat species coexist occupying different DNs.

We tested the hypothesis that tree species in a subtropical rain forest in south-east Queensland are ecologically equivalent and therefore have identical environmental requirements for their regeneration. We assessed the evidence that juveniles of species differed in their distributions in treefall gap microsites and along gradients of light availability, soil pH, soil PO4-P availability and soil NO3-N availability. Pairwise comparisons were made on a subset of the common species selected on the basis that they showed a relatively high level of positive association, and would therefore, a priori, be expected to have similar regeneration requirements. Detailed comparisons between the species failed to demonstrate evidence for species differentiation with respect to their tolerance of the disturbance associated with gap microsites or to the gradient of NO3-N availability. However, species differed markedly in their distributions along the soil pH gradient and along the gradients of light availability and soil PO4-P availability. The overall level of ecological differentiation between the species is high: seven out of the 10 possible species pairings showed evidence for ecological differentiation. Such niche differentiation amongst the juveniles of tree species may play an important role in maintaining the species richness of rain-forest communities.

Floral morphology often directly influences interactions with pollinators, but less is known about the role of extrafloral structures. We studied the relationship between bract motility, floral structural specialization and pollination in Dalechampia aff. bernieri, an endemic Madagascan species with floral structures indicating specialized buzz-pollination. We measured circadian bract angles in 47 inflorescences from 11 plants of D. aff. bernieri; in addition, we recorded any flower-visiting insects observed. The inflorescences had motile bracts with mean angles varying from ~50° at 00h00 to ~90° at 10h45. They were visited by buzz-pollinating Nomia viridilimbata bees (Halictidae), but also by non-buzz-pollinating Liotrigona bees (Apidae). The temporal pattern of bract motility observed in D. aff. bernieri may represent an extra-floral specialization to reduce visitation by non-pollinating visitors while maximizing visitation by diurnal buzz-pollinating bees.

We used a standardised transect method to compare lowland forest termite assemblages in Buton Island, Sulawesi, with transects in Sundaland. The four Buton transects were extremely depauperate with species density ranging from 1 to 6 species, which is around 10% of the species density in 11 described Sundaland transects. Soil-feeding species were absent from the Buton transects but represent some 43% of species in the Sundaland transects. The Buton transects have relatively high soil pH (6.7–7.9), which may be associated with depauperate termite assemblages. Most termite genera recorded in Sulawesi are wood nesters that can raft in floating wood, which is probably how they arrived in Sulawesi. The Macrotermitinae (fungus-growers) do not raft and probably flew across serendipitously. Geographic isolation, both on Buton and in Sulawesi more generally, and Buton’s underlying geology causing high soil pH, may account for the near-absence of soil-nesters and soil-feeders, none of which are known to raft.