Modeling climatic and hydrological suitability for an encroaching tree species in a Neotropical flooded savanna

Abstract

Woody encroachment converts savanna systems to forests, altering the composition and productivity of native forage species and the supply of several ecosystem services. In this study, correlative species distribution models were applied to predict the chances of proliferation of a flood-tolerant encroaching tree (Vochysia divergens, Vochysiaceae) over the large Pantanal savanna floodplain and to provide a management tool with the aim of defining strategies for invasion control and containment over natural pastures. BIOCLIM and DOMAIN, two correlative models based on presence data, were used, accurately defining areas with a higher risk of invasion based on abiotic limits for the species distribution. The results of the models indicate that areas with high precipitation in the warmest period of the year and high annual mean temperature increase the chances of occurrence of this species, thus increasing the risk of invasion. Maintaining the integrity of natural pastures in climatic zones that are favorable to invasion requires management strategies such as low livestock density and maintenance of the hydrological regime, which prevent the degradation of natural pastures. Therefore, the management of encroaching trees must consider the socioeconomic and ecological benefits of removing populations of such trees, while seeking a balance in the conservation of ecosystem services and human livelihoods.