Disturbance impacts of logging on ground herbaceous plant species richness, diversity, and composition of lowland rainforest of Papua New Guinea: herbaceous diversity in Tropical Papua New Guinea

The impact of logging activities on species richness, diversity, and composition of the ground herbaceous layer of the lowland forest of Papua New Guinea was analyzed. Data from the first multipurpose National Forest Inventory were collected in 52 plots from logged and unlogged low altitude forest on plains and fans (P) and forest on uplands (H) in Madang, West New Britain and Central Provinces. The abundance of 10, 609 ground herbaceous plants classified in 174 species from 103 genera and 35 families. Based on importance values, Arecaceae was the dominating family in both logged and unlogged P forest type, while Urticaceae and Arecaceae were dominating respectively in logged and unlogged H forest type. At species level, Donax canniformis and Elatostema beccarii are dominating the P type, and Elatostema novoguineensis and Selaginella durvillei the H type. Analysis of species richness, diversity, and composition showed significant differences between the two types with the H type being richer and more diverse than P type. No differences emerged between logged and unlogged of both types, indicating that the current intensity of disturbance does not seem to have a significant impact on the ground herbaceous layer. Since herbaceous species are an important component of the tropical forest diversity, further inventories must be conducted along a wider elevation gradient to make these results more robust and better observe species turn over patterns and beta diversity.