We studied density, size structure, and establishment sites of Coussapoa microcarpa in the Brazilian Atlantic rain forest. This species is a hemiepiphyte that begins its life in the tops of trees and survives the death of its host to become a free-standing tree. All individuals of C. microcarpa already rooted in the ground were recorded in a 3.43 ha (1.75 ha in lowland and 1.68 ha in submontane) sample of forest plots. Data on total height, root diameter at breast height, host height and diameter at breast height, as well as height, type and diameter of the establishment site were collected. Coussapoa microcarpa present a high density (36.5 ind. ha−1) and the population studied was composed mainly of young individuals. Young and adults differed in establishment sites. The diameter of establishment sites of young was narrower than the diameter of establishment sites of adults, which points out to a limiting factor (diameter of establishment site) regulating the establishment of C. microcarpa.

Plants can develop novel adaptations for nutrient acquisition in nutrient-limited ecosystems. These adaptations include colonization by roots of tree trunks and logs that can act as nutrient reservoirs. Termites may facilitate this root colonization by digging tunnels and accelerating decomposition in logs and tree trunks. We measured the frequency with which above-ground tree root colonization co-occurs with the presence of termites or their tunnels inside living trees above 20 cm dbh (n = 178) and dead tree trunks and logs at least 15 cm in diameter (n = 146) in a Bornean tropical forest. Roots above the soil surface co-occur with termite tunnels 39% more frequently than expected by chance in trunks of living trees and 17% more frequently than expected by chance in logs. By categorizing logs according to hardness through ease of penetration, we found that softer logs at a late stage of decay did not show co-occurrence of termite activity and roots to the same extent as harder logs. This suggests that trees forage where termites have removed physical barriers to colonization. In this fashion, termites may accelerate nutrient cycling in tropical rain forests.

Conversion of forests to agricultural land may require many bird species to use resources in fragmented landscapes in order to persist. Pasture trees can make agricultural landscapes more hospitable for birds, but we do not know what factors promote bird visitation to pasture trees. Bird use of 26 focal trees of a common pasture species, Sapium glandulosum (Euphorbiaceae), was examined in three pastures in a montane landscape in Costa Rica to understand factors influencing bird visitation. Bird visits were analysed in relation to pasture tree size, distance from forest edge, degree of isolation and epiphyte load. Foraging resources (epiphyte or tree substrate) were also measured. From May–July 2012, 52 bird species from 20 families were recorded from 926 unique visits. Bird visitation was best explained by tree size, degree of isolation and epiphyte load such that larger, more isolated trees with higher epiphyte loads attracted more birds. Birds preferred food resources from focal trees (51% of visits) rather than their epiphytes (5% of visits). The results corroborate previous findings that mature pasture trees, even when isolated, may contribute more to species persistence than smaller trees.

The effects of precipitation regime on the size of soil carbon (C) pools were compared in mature tropical dry forests of the Yucatan Peninsula. Our study included three forest stands in each, a dry site (potential evapotranspiration ratio = 3.2 mm mm−1; mean annual precipitation = 537 mm), a wetter site (2.0 mm mm−1; 993 mm) and a site in which water was comparatively less limiting (1.3 mm mm−1; 1086 mm). At each site, soil C pools in dead fallen phytomass (includes leaves, flowers, fruits, small twigs and deadwood debris) deposited on the litter layer and in roots and organic matter of the mineral soil (from the upper 10 cm) were measured in samples collected during the dry season. A high proportion of the total C pool (93–95%) was in the top 10 cm of soil in all forest sites. The smallest C pool was in roots (1.8–2.4% of the total C), meanwhile the C in the litter layer represented 3–5% of the total pool. These patterns were observed irrespective of study site. However, distribution of C (i.e. wood debris vs. fine litter) varied across sites; the proportion of the forest-floor C pool in wood debris decreased from 80% in the driest site, to 51% and 42% in 993-mm and 1086-mm sites, respectively. Overall, we observed that three pools (wood debris, roots and soil organic C) provide evidence for the significant decrease in soil C storage with increase in mean annual precipitation in Yucatan Peninsula. A potential explanation for this unexpected pattern includes an increasing C turnover time with decreasing mean annual precipitation, resulting in higher C accumulation per unit of C input in the driest site.