Taxonomic, Phylogenetic, and Functional Diversity of Ferns at Three Differently Disturbed Sites in Longnan County, China

Abstract

Human disturbances are greatly threatening to the biodiversity of vascular plants. Compared to seed plants, the diversity patterns of ferns have been poorly studied along disturbance gradients, including aspects of their taxonomic, phylogenetic, and functional diversity. Longnan County, a biodiversity hotspot in the subtropical zone in South China, was selected to obtain a more thorough picture of the fern–disturbance relationship, in particular, the taxonomic, phylogenetic, and functional diversity of ferns at different levels of disturbance. In 90 sample plots of 5 × 5 m2 along roadsides at three sites, we recorded a total of 20 families, 50 genera, and 99 species of ferns, as well as 9759 individual ferns. The sample coverage curve indicated that the sampling effort was sufficient for biodiversity analysis. In general, the taxonomic, phylogenetic, and functional diversity measured by Hill numbers of order q = 0–3 indicated that the fern diversity in Longnan County was largely influenced by the level of human disturbance, which supports the ‘increasing disturbance hypothesis’. Many functional traits of ferns at the most disturbed site were adaptive to the disturbance. There were also some indicators of fern species responding to the different disturbance levels. Hence, ferns may be considered as a good indicator group for environmental stress.

Changes of Phylogenetic and Taxonomic Diversity of Odonata (Insecta) in Response to Land Use in Amazonia

“…This may result from anthropogenic land uses, as the predominance of shrubby vegetation is more frequent on the banks of streams that drain pastures, palm monoculture, and other anthropogenic landscapes [86]. The positive relationship between the canopy of small trees and phylogenetic diversity may respond to the increased invasion of species adapted to disturbed environments [87,88]. This result is not consistent with the hypothesis proposed here that areas of anthropogenic use would show less phylogenetic diversity in response to a subset of species that would be favored by the environmental conditions created in the disturbed environments [89].…”

Elevational Pattern of Leaf Mine Diversity on Quercus variabilis Blume at Baotianman, Henan, China

“…Based on the number of each leaf mine type on each Q. variabilis tree ( Table S1 ), the following taxonomic Hill diversity indices of leaf mines were calculated for each tree individual with the “hillR” R package [ 80 ]. The taxonomic Hill numbers through different orders ( q values) have different meanings: (1) q = 0, species richness and it reflects the diversity of all species; (2) q = 1, Shannon entropy index and it reflects the diversity of common species; and (3) q = 2, inverse Simpson’ dominant index and it reflects the diversity of dominant species [ 80 , 81 , 82 ].…”

“…The following phylogenetic Hill numbers of leaf mines were then computed for each tree individual by the “hillR” R package [ 80 ]. The phylogenetic Hill numbers through different orders ( q values) are also closely related to different phylogenetic diversity indices: (1) q = 0, the phylogenetic Hill number is related to Faith’s phylogenetic diversity; (2) q = 1, the phylogenetic Hill number is related to Allen’s phylogenetic entropy; and (3) q = 2, the phylogenetic Hill number is related to Rao’s quadratic entropy [ 82 , 84 , 85 , 86 ].…”

A preliminary world checklist of fern-mining insects

“…The R package 'V. PhyloMaker' ( Jin and Qian 2019 ) can bind undetermined plant taxa to the backbone phylogeny of 'GBOTB.extended.tre' and generates the customised tree we needed ( Dai et al 2020 ). Here, we obtained the phylogenetic tree of our host fern families using the above method.…”

“…Ferns ( Pteridophyta , including both Lycopodiophyta and Polypodiophyta in the broad sense) are the second largest group of vascular plants, just after angiosperms ( Dai et al 2020 , Schneider et al 2004 ). With lower nutrition, higher defensive chemicals and no flowers, the interspecific associations between ferns and insects are often overlooked ( Mehltreter et al 2010 , Weintraub et al 1995 ).…”