Sediment flows in South America supported by daily
hydrologic-hydrodynamic modeling
Abstract
Suspended sediments (SS) contribute to the maintenance of several
ecosystems. However, intense soil erosion can lead to environmental,
social, and economic impacts. South America (SA) has very high erosion
and sediment transport rates. Here we present a detailed description of
the spatio-temporal dynamics of natural SS flows in SA using the
continental sediment model MGB-SED AS. We evaluate the model with daily
in-situ data from 570 stations, information from regional studies and a
global model. The model performance analysis showed that, in general,
there was a better adjustment of the simulated data with those observed
than with the information found in regional studies and of the global
model. The use of the hydrodynamic propagation method has allowed a
better representation of sediment flows in rivers and floodplains. Based
in the calibrated model results, SA delivers 1.00×10 t/year of SS to the
oceans, in which the Amazon (3.89×10 t/year), Magdalena (7.57×10 t/year)
and La Plata (5.07×10 t/year) rivers are the main suppliers. The
floodplains play an essential role, retaining about 9.4% (1.11×10
t/year) of the SS loads reaching the rivers. In this study, datasets
related to SS flows in SA were generated and can be used to support
other large-scale researches or policymakers and stakeholders for
adequate management of continental land use.