Phorophyte size and soil profiles differentially correlate with community structure among hemiepiphytes and nomadic vines

Abstract

Tropical non‐self‐supporting plants such as hemiepiphytes and nomadic vines are model organisms for disentangling biotic and environmental correlates which influence their occupancy patterns. We inventoried >4000 individuals from >3000 trees ranging from 1 to 200 cm diameter at breast height (DBH) in a northeastern Amazonian upland forest to address how tree (phorophyte) size, edaphic factors and recruitment strategy influence occupancy, diversity, and compositional patterns of two vascular non‐self‐supporting plant functional groups. Hemiepiphytes germinate on phorophytes prior to establishing soil connections, whereas nomadic vines initiate their life cycle on the forest floor and subsequently climb phorophytes for crown access, abandoning roots replaced by adventitious connections which may reach the ground. Our results show that larger phorophytes (≥30 cm DBH) supported more species for both hemiepiphytes and nomadic vines. However, nomadic vines' occupancy probabilities saturated faster at smaller stem sizes than that of hemiepiphytes indicating differential preferences for stem sizes among the two functional groups. For smaller phorophytes (<30 cm DBH), soil correlations were stronger with nomadic vines than hemiepiphytes, whereas no significant differences were detected among functional groups in relation to edaphic factors for larger (≥ 30 cm DBH) ones. Finally, a small core group of species showed disproportionately greater abundances among large phorophytes suggesting that autogenic processes differentially promote survivability. Such interactions among phorophyte size and edaphic factors may result from the contrasting ecological requirements of hemiepiphytes and nomadic vines at the recruitment stage, demonstrating the necessity for elaborate demographic‐based studies to better understand these complex plant–plant interactions. Abstract in Spanish is available with online material

Climbing aroids in a Panamanian lowland forest: We should reconsider our categories

“…Although the ecology and diversity of non‐woody climbers has not been completely ignored (e.g. Balcázar‐Vargas et al., 2012; Rogalski et al., 2016; Núñez Castro et al., 2019; Clemente‐Arenas et al., 2023), the group remains poorly studied, while structurally dependent woody plants like lianas have seen an enormous increase in research interest over the last decades (reviewed in Putz & Mooney, 1991; Schnitzer et al., 2015; Pandi, 2023). Commonly studied aspects were the vertical distribution of aroids, which could be linked to growth form, that is, hemiepiphytic, lianescent or epiphytic, and to morpho‐physiological traits (Mantovani, 1999; Nieder et al., 2000; Jácome et al., 2004; Petter et al., 2016; Rogalski et al., 2016).…”