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Tropical rangelands are composed of heterogeneous landscape mosaics associated with soil properties, topography and climates with highly variable primary productivity and species composition controlled mainly by seasonal precipitation that can be influenced by natural (e.g. flooding, wildfire) or human (e.g. fire, grazing) disturbance regimes at multiple scales resulting in three broad habitat configurations: savanna grassland, savanna shrublands and savanna woodlands. The encroaching woody species by the proliferation of indigenous woody species on savanna grassland leading to a decline in biodiversity and grazing capacity of both wild and domestic herbivores. The purpose of this research is to characterize influences of increasing Byrsnonima. cydoniifolia on vegetation structure in the sandy Pantanal habitats and to identify and predict states and thresholds using state-and-transition models (STM). In order to develop the STM, we measured vegetation structure and diversity in areas invaded by B. cydoniifolia, and used these values to determine the presence of thresholds for the development of conceptual STM. Three states (reference, invasive and degraded) were identified for savanna woodland, savanna shrublands, savanna grassland and wetland ponds vegetation types. Significant breakpoints values for B. cydoniifolia density and Pielou�s evenness index were identified in savanna woodland and savanna shrublands (421 and 649 stems ha-1 respectively). Our results suggest that the expansion of B. cydoniifolia and subsequent switch to an alternative state, is a process driven mainly by climatic conditions rather than overgrazing. This finding has significant implications for the management and conservation of the Pantanal grazing areas in light of predicted climate change.