Population Structure of Osmunda regalis in Relation to Environment and Vegetation: An Example in the Mediterranean Area

Abstract

The structure of 42 natural populations of the endangered fern Osmunda regalis was studied at the southern limit of its European distribution. The aims were to i) investigate the population structures and status of the species; ii) test which local habitat and population characteristics correlate with the different population structures in the Mediterranean area; iii) evaluate which habitat types are suitable to support viable populations. The structure of populations is determined by the attribution of different stages of development of the sporophyte. This study documented the life-stage structure of O. regalis using an original classification of life stages that may be applicable to other fern populations with similar morphology. Using statistical analyses we distinguished: i) dynamic populations, which are characterized by a large proportion of sporelings and vegetative adults and are associated with streams and nemoral species; ii) stable populations, with a higher proportion of generative adults, growing prevalently in habitats rich in hygrophilous grasses and shrubs, with lower tree cover; iii) senile populations, with a relatively higher proportion of senescent individuals and with marked rejuvenation dominated by vegetative adults, which are prevalently located in spring swamps. The proportion of senescent stage individuals is positively correlated with the mean geographic distance between populations. Spring swamps, with populations that provide a clear example of remnant dynamics, are the habitat with the most stable conditions for O. regalis in the Mediterranean area.

Population Study of the Golden Chicken Fern (Cibotium barometz (L.) J. Sm. in Riau Province, Sumatra

“…The transects commonly covered 25 -30% of the total distribution area of C. barometz. Population size in a certain area was determined as the local population, following the method described by Landi and Angiolini [21]; the local population of C. barometz is a cluster of plants of the species separated from other clusters by at least 500 m.…”

First steps to study the demography of vascular epiphytes in cities

“…After the census, we calculated the proportion of individuals belonging to each stage for each population. Subsequently, the resulting structures were classi ed according to the proposal by Landi and Angiolini (2011). To compare population structures between the two epiphytic species, and between the two phorophyte origins (native vs. exotic), we conducted a two-way multivariate analysis of variance (MANOVA) to detect any overall differences in the proportion represented by each life stage (response variable).…”

“…Despite all the unfavorable factors mentioned, vascular epiphytes have been reported in cities ( A rst step in this direction involves examining the structure of these urban populations of epiphytes by looking at the proportion of individuals corresponding to each of the life stages recognized for these plants. This provides a quick and general notion of the demographic status of a population (Oostermeijer et al 1994;Landi and Angiolini 2011; Ramírez-Martínez et al 2018). Landi and Angiolini (2011) developed the following classi cation to describe populations based on their demographic structure:…”

“…This provides a quick and general notion of the demographic status of a population (Oostermeijer et al 1994;Landi and Angiolini 2011; Ramírez-Martínez et al 2018). Landi and Angiolini (2011) developed the following classi cation to describe populations based on their demographic structure:…”

Combined LM and SEM study of the Middle Miocene (Sarmatian) palynoflora from the Lavanttal Basin, Austria: Part I. Bryophyta, Lycopodiophyta, Pteridophyta, Ginkgophyta, and Gnetophyta

“…It is also found growing in ponds and along streams in deciduous or coniferous upland forests, and Osmunda regalis L. apparently typifies small ponds throughout the temperate forest regions in North America and Europe (cf. Flinn et al, 2008;Landi & Angiolini, 2011).…”