Savanna resilience to droughts increases with the proportion of browsing wild herbivores and plant functional diversity

Maintaining the resilience and functionality of savannas is key to sustaining ecosystem services they provide. This maintenance largely dependent on stressors, such as prolonged droughts. The drought determined by interaction herbivores functional composition vegetation. So far, our understanding ability predict response under different types rangeland use a function vegetation are still limited. In this study, we used ecohydrological, spatially-explicit savanna model EcoHyD determine if towards droughts can be enhanced choice type (grazer-dominated, mixed-feeders or browser-dominated) animal density. We evaluated Namibian system withstand recover from based its perennial grass cover overall species composition. Generally, low high grazer densities. Most importantly, found that diversification plants acted insurance against droughts, leading greater resistance recovery grasses. particular, higher proportion allowed for resilience, probably also due short-term switch more drought-resistant unpalatable species. case, herbivore was self-regulatory value reestablishing trophic complexity, reducing need additional management interventions. Synthesis applications: Savanna systems will resistant (i) dense maintained, protecting topsoil heat-induced water losses erosion, encompassing functionally important particularly well adapted stress palatable, (ii) grazing pressure adjusted productivity system, (iii) community includes browsers.