Simplified Hydrological Response Units Map for South America

The representation of physical characteristics differences in watersheds is one of the major challenges on distributed hydrological models application. In this sense, a commonly used technique is the definition of Hydrologic Response Units (HRUs), which are hydrologically homogeneous regions within the basin.

Here we make available a HRUs map to all of South America. An HRU map is, generally, defined from the combination of soil type and soil use maps, and may also include other variables such as geology and topography. Besides being a particular product to meet hydrological models needs, it reduces input data preparation time. The final map has been used in various applications with the MGB-IPH model. Simulation results with the map were satisfactory in many applications (Fan et al., 2015).

URHs para a América do Sul, resultante da combinação dos mapas de tipos e usos do solo simplificados.

URHs para a América do Sul, resultante da combinação dos mapas de tipos e usos do solo simplificados.

(Figure: URHs to South America, the resulting combination of soil types and simplified land uses maps)

The main reference to map HRUs of South America, where details of the generation process are available, is:

Fan F. M., Buarque D. C., Pontes, P.R.M., Collischonn W. AN HYDROLOGICAL RESPONSE UNITS MAP FOR ALLSOUTH AMERICA. XXI Simpósio Brasileiro de Recursos Hídricos, Novembro de 2015, Brasília-DF. Anais do XXI Simpósio Brasileiro de Recursos Hídricos. PAP019919. 2015.

The map is available with a spatial resolution of 400m here along with a descriptionfile and the reference above.

* The URHs file is avaiable in the binary format .irst. To work with and edit it you can use the IPH-Hydro Tools plugin.


We recommend that the map must be used with caution, always checking that the data is suitable for the study area. We do not take responsibilities for the use of information. And remember that this is just one more information that can be used in hydrological studies, among many available. And that there are always uncertainties in the data used for the map derivation.

In case the map is used for the application of the MGB-IPH model, it is recommended to check if the URH water appears in the basin after clipping to the basin area. If URH water does not appear, the user must include the URH water  through some GIS map tool. Because the MGB-IPH model requires that your last URH is water for the application.