Reproductive traits as predictors of assembly chronosequence patterns in epiphyllous bryophyte metacommunities

Abstract

Understanding the mechanisms underlying species assembly is a central focus of plant ecology and is crucial to revealing how plant communities are structured. However, the temporal limitations of most terrestrial plant communities preclude collection of species assembly data in a tractable time‐frame. The aim of this study is to investigate the importance of dispersal potential, as estimated by interspecific variation in sexual and asexual expression, as a predictor of patch chronosequence assembly for epiphyllous (leaf‐inhabiting) bryophytes. Secondarily, we investigate whether spatiotemporal patterns in patch turnover and compositional variation infer evidence of local (within‐patch) population processes. The frequency and distribution of 55 epiphyllous bryophytes across five leaf age classes were studied on an understorey shrub Piper grande (Piperaceae) in premontane Panamanian tropical forest. Logistical models were used to test whether interspecific variation in dispersal‐related life‐history traits predicts assembly order. Beta diversity and ordination analyses were employed to examine nestedness vs. turnover, and probe for repeatable patterns in patch chronosequence assembly, respectively. Our results emphasize the importance of dispersal potential on species assembly patterns as earlier arrivals exhibit greater probabilities of sexual and specialized asexual expression. High turnover coupled with temporal convergence in species composition also points to evidence of within‐patch biotic filtering. Synthesis. Epiphylls are locally diverse in humid tropical forests worldwide; however, the mechanisms which maintain their high local diversity are unknown. This study suggests that interspecific variation in dispersal capacity in combination with diffuse indirect effects is the principal contributor to the high alpha‐diversity of these ephemeral metacommunities.

Epiphyte Colonisation of Fog Nets in Montane Forests of the Taita Hills, Kenya

“…High reproductive output, as indicated by the frequent presence of sporophytes in the monoecious liverworts Lejeunea flava and L. tabularis, or by the common and often abundant production of asexual propagules such as gemmae in the dioecious liverwort Metzgeria furcata or soredia in the lichens Heterodermia comosa and Normandina pulchella, most likely are an important determining factor for the successful dispersal and establishment of these epiphytes. It may also be an important element in explaining chronsequence patterns of the epiphyte communities, as predicted by Sierra et al (2019) for epiphyllous bryophytes. In our data set, the frequency of common, effectively dispersing species was usually rather equal on up-and downwind nets at each site, largely explaining the often conspicuous pairing of the nets in the ordination (Fig.…”

Diversidad y distribución de briófitos epífilos en <i>Beilschmiedia costaricensis</i> (Mez & Pittier) C.K. Allen (Lauraceae)

“…Sin embargo, la composición de las comunidades fue similares en las tres zonas. Se ha documentado que la familia Lejeuneaceae forma el 90 % de las comunidades de hepáticas epífilas en la mayoría de los bosques tropicales (Cornelissen y Ter Steege, 1989;Marino y Salazar-Allen, 1992;Dauphin, 1995;Pócs, 1996;Zhu y So, 2001;Mota de Oliveira et al, 2009;Sierra et al, 2018). De manera similar, en el Sendero Panamá Verde la familia Lejeuneaceae representó el 70 % de la diversidad.…”

“…También pudimos evidenciar que los árboles de B. costaricensis albergan comunidades de briófitos epífilos accidentales, por ejemplo, briófitos epífitos de la corteza u otros sustratos que lograron establecerse y adaptarse al sustrato de las hojas. En otro contexto, Sierra et al (2018) indican que la composición de especies en las comunidades epífilas no depende de la secuencia cronológica en el hospedador y proponen que los cambios no siguen una dinámica de sucesión, sino que es un proceso al azar. Como en nuestro caso la distancia entre las zonas era de aproximadamente dos metros, la composición de las comunidades también puede atribuirse a la capacidad de dispersión de los briófitos (Zartman et al, 2015).…”

500 million years of charted territory: functional ecological traits in bryophytes

“…Patiño et al 2013, Löbel et al 2018, Tiselius et al 2019. For example, Sierra et al (2019) have shown that propagule characteristics predict succession in high diversity tropical epiphyll community. Even within a species, primary propagule type can vary according to habitat and population (e.g.…”

“…Despite some recent studies of tropical (e.g. Sierra et al 2019, Marks et al 2019a, sub-tropical (e.g. Wang et al 2017b, Fan et al 2020) and mediterranean (e.g.…”