Distribution of Liana Richness and Abundance in the Forest of Papua New Guinea

This study surveys liana communities at 26 sites across undisturbed and disturbed forests from 70 to 2,700 m above sea level in northern parts of Papua New Guinea (PNG). The assessment was conducted following the Papua New Guinea National Forest Inventory (NFI) manual. The results show a total diversity of 68 genera of lianas, belonging to 33 families. No significant difference was observed in abundance of liana species between lowland unlogged (i.e., primary and pristine) and logged (disturbed) forests and lower montane unlogged forests. Richness is not significantly different between lowland and montane sites, as opposed to outcomes in other studies which have often reported a decrease in species richness with elevation. Both types of lowland forests do not show indicator genera, while the unlogged montane forests are characterized by Rubus and Sabia genera. The study shows a high taxonomic richness of lianas in PNG, supporting previous research and underlining that they make a significant contribution to the overall woody species richness and to the ecology and complexity of PNG forest.</jats:p

Fern Species Richness and Diversity in the Forest Ecosystems of Papua New Guinea

This study aims to analyze the occurrence and composition of ferns along an elevational gradient and among different forest types and disturbance regimes in Papua New Guinea (PNG). The assessment was conducted using the monitoring protocol of the National Forest Inventory. The investigation revealed a high richness of ferns, with 122 species or morphospecies from 51 genera and 21 families. Among them, 81 species were terrestrial and 16 were epiphytes. The project also highlighted increasing richness with elevation, both for terrestrial and epiphytic ferns. Reflecting other environmental variables, elevation was a significant proxy factor in determining the taxonomic composition. Lowland forest was clearly differentiated from the montane one, which was characterized by epiphytic species from the Drynaria and Ctenopteris genera. Lowland disturbed and primary forests were slightly differentiated in terms of fern composition, the latter characterized by sciophilous species belonging to the Polypodium, Microlepia, and Pronephrium genera and the former mainly by species of the Gleichenia genus adapted to forest margins and gaps. The research points to the richness of ferns in PNG and their effectiveness as a potential indicator to characterize and monitor forest types and their conservation status with respect to a disturbance regime. In the future, studies should aim to increase species sampling in abundance and seek precision in understanding species response variables in diverse forest regimes.</jats:p

New Guinea has the world’s richest island flora

New Guinea is the world’s largest tropical island and has fascinated naturalists for centuries1,2. Home to some of the best-preserved ecosystems on the planet3 and to intact ecological gradients—from mangroves to tropical alpine grasslands—that are unmatched in the Asia-Pacific region4,5, it is a globally recognized centre of biological and cultural diversity6,7. So far, however, there has been no attempt to critically catalogue the entire vascular plant diversity of New Guinea. Here we present the first, to our knowledge, expert-verified checklist of the vascular plants of mainland New Guinea and surrounding islands. Our publicly available checklist includes 13,634 species (68% endemic), 1,742 genera and 264 families—suggesting that New Guinea is the most floristically diverse island in the world. Expert knowledge is essential for building checklists in the digital era: reliance on online taxonomic resources alone would have inflated species counts by 22%. Species discovery shows no sign of levelling off, and we discuss steps to accelerate botanical research in the ‘Last Unknown’8