Understanding biodiversity patterns in this changing world is extremely important in order to conserve the worldwide biodiversity. Sumatra is the sixth largest island worldwide and one of the world´s biodiversity hotspots. Nowadays, Sumatra´s biodiversity is highly threatened by forest conversion into agricultural landscapes such as rubber and oil palm plantation. In these cultural landscapes native species are not only threatened by habitat loss, but they are also often replaced by introduced and often invasive alien species.
The goal of this study is to understand the impact of forest conversion and introduction of non-native species on phylogenetic plant diversity in four land-use systems: lowland rainforest, jungle rubber agroforests, rubber plantations and oil palm plantations.
Based on the present dataset on taxonomic plant diversity within the EFForTS study area, the phylogenetic plant diversity will be analyzed with a focus on understory communities which are most affected by the invasion of non-native plant species. Taxonomic and phylogenetic diversity indicator (indices) approach will be incorporated in the analyses.
Four main hypotheses will be investigated: (1) the community structure based on phylogenetic diversity varies across the different land-use systems. (2) Contrary to taxonomic diversity, the phylogenetic diversity is higher in agricultural landscapes due to higher amounts of introduced species from plant families which are absent in the natural vegetation. (3) Phylogenetic plant diversity is more clustered in converted habitats indicating closely related species with similar traits co-occur. (4) The amount of non-native species in the different land-use systems influences phylogenetic diversity.