Lianas research in the Neotropics: overview, interaction with trees, and future perspectives

Key message A systematic review (1950-2018) summarizes the research on woody lianas and their interaction with trees in the Neotropics. We identify knowledge gaps, propose new directions for future studies and discuss the control, management, and conservation of lianas. Lianas are key components of species composition, structure and dynamics of tropical forests. Current global warming scenario, however, are favoring increases in the abundance and density of lianas in tropical forests, affecting tree growth, fertility, and the number of tree injuries, therefore, increasing tree mortality over time. Here, we present a systematic review of studies on Neotropical lianas and its relation with trees, aiming to (1) establish the current state of ecological research, identifying knowledge gaps and propose new directions and perspectives for future studies; (2) offer baseline knowledge to support the control, management and conservation of lianas. We surveyed the literature on lianas (woody climbers) since 1900 to 2018 retaining 427 papers. We organized the literature by country, vegetation type, topic addressed and whether the study focused exclusively on lianas or lianas and trees. Our review demonstrated the importance of lianas in tropical forests, and the scarcity of studies on woody savannas and especially extremely dry vegetations as the Caatinga seasonally dry forests and xeric shrublands. Regardless of their remarkable importance and their contribution for diversity, biomass and carbon flux, lianas are rarely included in global vegetation models and have been overlooked in restoration, control, and management programs. We must consider the relevance of lianas in maintaining diversity and microclimate, and as resources for native animals, such as pollinators, herbivores, and seed dispersers, as well as for traditional human communities. Research on ecophysiology and functional spectral traits, and management of lianas are among the key areas in the Anthropocene.