What are the flows of the smaller, ungauged Rio Mangaraí?
The RIo Mangarai is a "target" tributary of the Rio Santa Maria da Vitoria. It has multiple landuses, produces high levels of sediments, and "flashy" response to rainfall events The interests are to understand the flow regime, as a function of the landuses, and how the sediments are mobilized and transported. But there are no gauges in the basin, so there are no historical records. There are no meteorological measuring stations, so any descprtion of weather patterns has to be interpolated from broader coverages.
A first order description of the hydrology is provided by sub-setting the DHSVM hydrology model of the SMV. An important consideration is that while the model can predict the discharge regime, there are no gauges to provide measured discharge. This indicates an important aspect to the models - that they can be extrapolated to regions where no data exists, with some degree of confidence. (Click here to see the preliminary model results).
Preliminary DHSVM setup of the Rio Mangarai, noting that there are no observed values for comparison
In the next phase of PCGAP development, a high-resolution model of the Rio Mangarai could be developed. Recently-completed work by HiParc could provide higher resolution description of the basin attributes for improved model results. Field gauges should be installed, to provide observations on actual flow, for comparison to model results.
High resolution DEM from SRTM of the Rio Mangarai watershed