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Land use/land cover change (LUCC) combined with gold mining activity (GMA) have reportedly affected the water quality of Amazonian rivers by intensifying surface soil erosion and increasing rivers’ sediment concentration (SC). However, the role of LUCC on river siltation in comparison to that caused by GMA has not been assessed, and predictions of SC in the rivers accounting for future LUCC are scarce. This study applied a sediment modeling approach on Crepori Basin, located at eastern Amazon Basin, to simulate the impacts of past and future LUCC on SC in the river, comparing their impacts to those caused by GMA. Between 1973 and 2012, the expansion of deforested areas in the region had increased sheet erosion-driven SC in the river, especially during the high-water season, by up to 73.3%. LUCC projections for 2050 suggest future increases in sheet erosion-driven SC during the high-water season by more than three times of that caused by the land cover scenario of 1998–2012. Comparison between SC driven by sheet erosion to that caused by GMA has also shown that during the high-water and the low-water seasons, respectively, only about 14% and 6% of the total SC in the Crepori River resulted from laminar soil erosion, with the remaining proportion resulting from GMA.

Quality results depends on the available data accuracy. Topographic data for the entire globe from SRTM - Shuttle Radar Topography Mission are free and, if correct, they represent a powerful resource for the territorial and environmental planning. However, its use, in models for information systems, must be evaluated in order to assess the information reliability. The aim of this study was to verify the similarity between a soil loss map generated from SRTM DEM and another from a higher resolution. USLE model - Universal Soil Loss Equation was applied with the intention of estimate soil loss rates in a basin on the northeast of Sao Paulo State in Brazil. Therewith it was possible to assess the performance of SRTM DEM. The similarity was checked using the Kappa index, which shows the degree of similarity between maps through an error matrix. The Kappa index revealed that SRTM DEM has an accuracy level considered reasonable (0.6594), while Kappa values for LS factor (0.2584), natural erosion potential (0.2582) and estimated soil loss (0.4199) accuracy levels are considered low, low and moderate, respectively. Therefore, this study showed that the application of SRTM DEM can offer satisfactory results when multiplied by higher quality data in basins where LS is not a decisive factor in estimated soil loss, but must be used carefully in other conditions.

Land cover changes (LCC) affect the water balance (WB), changing surface runoff (SurfQ), evapotranspiration (ET), groundwater (GW) regimes, and streamflow (Q). The Tapaj&oacute, s Basin (southeastern Amazon) has experienced LCC over the last 40 years, with increasing LCC rates projected for the near future. Several studies have addressed the effects of climate changes on the region&rsquo, s hydrology, but few have explored the effects of LCC on its hydrological regime. In this study, the Soil and Water Assessment Tool (SWAT) was applied to model the LCC effects on the hydrology of the Upper Crepori River Basin (medium Tapaj&oacute, s Basin), using historical and projected LCC based on conservation policies (GOV_2050) and on the &ldquo, Business as Usual&rdquo, trend (BAU_2050). LCC that occurred from 1973 to 2012, increased Q by 2.5%, without noticeably altering the average annual WB. The future GOV_2050 and BAU_2050 scenarios increased SurfQ by 238.87% and 300.90%, and Q by 2.53% and 2.97%, respectively, and reduced GW by 4.00% and 5.21%, and ET by 2.07% and 2.43%, respectively. Results suggest that the increase in deforestation will intensify floods and low-flow events, and that the conservation policies considered in the GOV_2050 scenario may still compromise the region&rsquo, s hydrology at a comparable level to that of the BAU_2050.

The article which was recently published contained error. The second given names “Andrade” and “de Lucia” were captured as particles. Given in this article is the correct naming of authors.