Beyond simple plant-animal interactions, we will discuss how defaunation triggers deep changes in the multi-trophic above-belowground tropical forest system and drives structure and function in these systems, to define the critical central role of large vertebrates for tropical forest conservation.
Redford’s metaphor of the empty forest prevails on the minds and souls of tropical ecologists and conservationists alike. Yet, almost 30 years on since Redford’s seminal publication we continue with limited evidence on the impacts and mechanisms of defaunation effects on the structure and function, diversity and ecosystem functions of tropical forests. A key missing gap in this body of evidence pertains how large herbivore effects integrate and scale with direct & indirect linkages among above and belowground organisms and abiotic properties. For instance, beyond intuitive trophic interactions, large vertebrates might affect plants through non-trophic interactions (e.g. trampling) and overrun or compensate the effects of invertebrate foliar herbivores and seed predators, microbial root symbionts and pathogens, contingent on the local soil fertility or other abiotic features. In face of rapid global changes (e.g. species extinctions, land-use, biological invasion) the outcome of such interactions can change, but characterizing the mechanisms involved and their importance needs further attention given the alarming levels of defaunation and threats to hyper-diverse and dynamic tropical forests.
This exciting session will integrate the latest and more robust experimental evidence about the importance of conserving large terrestrial vertebrates aiming to preserve the structure and diversity in tropical systems, building on evidence from three continents (America, Africa and Asia). Through a walkabout through different large vertebrate exclosure and natural experiments we will explore how the presence of tropical forest’s largest ecosystem engineers integrates with other key above and belowground processes to ultimately define the structure and function of tropical forests. We will do so with an interactive and “funky” session, in which the audience will learn, think and have loads of fun.
Photo: João Paulo Krajewski
Claudia Paz, Sao Paulo State University
Yuri Silva Souza, Sao Paulo State University
Integrating defaunation with other key drivers of structure and diversity of tropical forests [OFS-3]