Flooding and land use change in Jambi Province, Sumatra: integrating local knowledge and scientific inquiry

The rapid expansion of rubber and oil palm plantations in Jambi Province, Sumatra, Indonesia, is associated with largescale
deforestation and the impairment of many ecosystem services. According to villagers’ observations, this land use change has,
together with climate change, led to an increase in the magnitude and frequency of river flood events, which constrain village and
plantation development. Based on this empirical societal problem, we investigate whether we can find measurable indications for the
presumed linkages between land use change, climate change, and changing flooding regimes. We follow an explorative, bottom-up
research approach that builds on a review of multidisciplinary datasets, integrating local ecological knowledge with scientific
measurements from soil science, climatology, hydrology, and remote sensing. We found that water levels of one of the largest rivers in
Jambi Province, the Tembesi, have increased significantly during the last two decades. Data of local and regional meteorological stations
show that alterations in rainfall patterns may only partly explain these changes. Rather, increased soil densities and decreased water
infiltration rates in monoculture plantations suggest an increase in surface runoff following forest conversion. Moreover, additional
interview data reveal that an increasing encroachment of wetlands in Jambi Province may contribute to changes in local flooding
regimes, as the construction of drainage and flood control infrastructure redistributes floodwater at the local scale. We conclude that
changing flooding regimes are the result of multiple interacting social-ecological processes associated with the expansion of rubber
and oil palm plantations in Jambi Province. Although ecohydrological changes are likely to contribute to an increase of flood occurrence,
their social impacts are increasingly mediated through flood control infrastructure on industrial oil palm plantations.