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We assessed fragmentation impact on liana community structure and patterns of liana-tree interaction network structure, and edge effects on liana community structure in a rainforest and a moist semi-deciduous (MSD) forest in Ghana. In each forest, we randomly established 30 20 Â 20 m 2 plots at varied distances (0-20 m, 20-40 m, 40-60 m, 60-80 m, 80-100 m) from forest edge to interior in fragmented and intact sites. Lianas with diameter at 1.30 m from rooting base ≥1 cm and their host trees (diameter at breast height ≥ 5 cm) were identified and counted. Our findings revealed that fragmentation caused an increase in liana diversity in the rainforest, but not in the MSD. Fragmentation also resulted in shifts in species composition in both forests, and together with edge effects increased liana abundance in both forest ecosystems. Lianatree networks in the two forest ecosystems were less nested and connected, but more modular and specialized than their corresponding null models irrespective of fragmentation. Some species of lianas (rainforest fragment/ intact: 0.80/0.76%; MSD fragment/intact: 0.47/0.38%) and trees (rainforest fragment/intact: 0.65/0.35%; MSD fragment/intact: 0.54/0.36%) exhibited higher specialization than their null models. Topologically, most lianas in fragmented and intact sites of the forests played peripheral/specialist roles, whereas a few species exhibited structural importance in the form of connectors, network hubs and module hubs. The structural important species in fragmented sites did not also occur in intact sites, suggesting that fragmentation might have influenced topological roles of the species in fragmented sites.

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Edge disturbance can drive liana community changes and alter liana-tree interaction networks, with ramifications for forest functioning. Understanding edge effects on liana community structure and liana-tree interactions is therefore essential for forest management and conservation. We evaluated the response patterns of liana community structure and liana-tree interaction structure to forest edge in two moist semideciduous forests in Ghana (Asenanyo and Suhuma Forest Reserves: AFR and SFR, respectively). Liana community structure and liana-tree interactions were assessed in 24 50 × 50 m randomly located plots in three forest sites (edge, interior and deepinterior) established at 0-50 m, 200 m and 400 m from edge. Edge effects positively and negatively influenced liana diversity in forest edges of AFR and SFR, respectively.There was a positive influence of edge disturbance on liana abundance in both forests.We observed anti-nested structure in all the liana-tree networks in AFR, while no nestedness was observed in the networks in SFR. The networks in both forests were less connected, and thus more modular and specialised than their null models. Many liana and tree species were specialised, with specialisation tending to be symmetrical.The plant species played different roles in relation to modularity. Most of the species acted as peripherals (specialists), with only a few species having structural importance to the networks. The latter species group consisted of connectors (generalists) and hubs (highly connected generalists). Some of the species showed consistency in their roles across the sites, while the roles of other species changed. Generally, liana species co-occurred randomly on tree species in all the forest sites, except edge site in AFR where lianas showed positive co-occurrence. Our findings deepen our understanding of the response of liana communities and liana-tree interactions to forest edge disturbance, which are useful for managing forest edge.

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